Humans and robots will increasingly have to work together in the new industrial context. Therefore, it is necessary to improve the User Experience, Technology Acceptance, and overall wellbeing to achieve a smoother and more satisfying interaction while obtaining the maximum performance possible out of it. For this reason, it is essential to analyze these interactions to enhance User Experience. The heuristic evaluation is an easy-to-use, low-cost method that can be applied at different stages of a design process in an iterative manner. Despite these advantages, there is rarely a list of heuristics in the current literature that evaluates Human-Robot interactions both from a User Experience, Technology Acceptance, and Human-Centered approach. Such an approach should integrate key aspects like safety, trust, and perceived safety, ergonomics and workload, inclusivity, and multimodality, as well as robot characteristics and functionalities. Therefore, a new set of heuristics, namely, the HEUROBOX tool, is presented in this work in the form of the HEUROBOX tool to help practitioners and researchers in the assessment of human-robot systems in industrial environments. The HEUROBOX tool clusters design guidelines and methodologies as a logic list of heuristics for human-robot interaction and comprises four categories: Safety, Ergonomics, Functionality, and Interfaces. They include 84 heuristics in the basic evaluation, while the advanced evaluation lists a total of 228 heuristics in order to adapt the tool to the evaluation of different industrial requirements. Finally, the set of new heuristics has been validated by experts using the System Usability Scale (SUS) questionnaire and the categories has been prioritized in order of their importance in the evaluation of Human-Robot Interaction through the Analytic Hierarchy Process (AHP). An increasing number of robots have been incorporated over the last years into Industry 5.0 , which cCollaborative robots are particularly suited to addressing challenges related to manufacturing and assembly tasks, as they can interact physically with humans in a shared workspace . ConversHuman-robot coexistence, denoting two entities–human and robot–operating simultaneously within a shared workspace.• Human-robot cooperation, signifying both entities working together in the same environment towards a common goal.• Human-robot collaboration (HRC), which additionally requires direct physical interaction between the two entities.• Prior research offers various interpretations of Human-Robot Interaction (HRI). This investigation aligns with the perspective presented by Industrial and scientific research on HRI tends to be predominantly oriented towards technical issues and technological solutions . This “rNowadays, the interaction between human operators and robots are an unresolved concern across various application domains, ranging from healthcare and surgical procedures to personal services, with a particular emphasis on industrial contexts . UndoubtThe analysis of HRI variables is of great importance in robotics, as it allows for a comprehensive understanding of the dynamics of interactions between humans and robots. By examining factors such as communication, task allocation, and reliability between humans and robots, researchers can identify potential challenges and opportunities for improving collaboration and enhancing performance. Additionally, such analysis can inform the development of effective collaboration strategies and enable the design of robotic systems that better align with human needs and preferences. The growing prevalence of robotics in manufacturing underscores the importance of HRI variables. Understanding the factors that influence successful HRI can help to maximize the potential benefits of robotics while minimizing the risks and challenges associated with their use.This paper focuses on the design for HRI, specifically in the context of modern factories where robots work alongside humans to support task execution. The research motivation stems from the desire to expand current research efforts, which have predominantly concentrated on the technological aspects of robotic systems, to encompass the human side of the collaboration. The need for such research is increasingly relevant as robotics technology advances and becomes more prevalent in industrial settings, where humans and robots must work together seamlessly to achieve optimal performance. By exploring collaboration from the human perspective, this research aims to identify effective ways to enhance collaboration and promote a more intuitive, fluid, and satisfying interaction between human and robotic agents. Thus, this study proposes an innovative instrument for assessing the degree to which the robot’s design, contextual features, and organizational characteristics align with the individual to facilitate efficient, effective, seamless, and satisfactory interactions.This document is structured as follows. For a better understanding of the concepts, all the theoretical definitions are introduced in The The Technology Acceptance Model (TAM) is a widely used theoretical framework that aims to understand and predict user acceptance of technology . In the In this sense, In order to effectively design HRI environments, the evaluation phase serves as a crucial step in the design process as emphasized in the UX design workflow for HRI . It enabThe literature has identified various types of measurements to assess HRI, including performance indicators, postural indicators, robot-related factors, or even emotion-related factors . To captAs the field of HRI continues to evolve, there is an increasing need for new and innovative evaluation methods to assess the performance and effectiveness of these systems or the use of traditional methods in novel ways . This paThe heuristic evaluation is a widely used method based on evaluators’ criticism for the quick identification of design issues  because The traditional sets of heuristics are Nielsen`s 11 Heuristics, Norman`s 7 Principles of Usability , and theRegarding heuristics and guidelines for HRI, i) Safety, trust, and perceived safety. Ensuring safety is the key challenge in HRI design and implementation . The intii) Physical ergonomics. New robotic environments must be able to prevent worker discomfort as well as aggravation of diseases related to postural or physical conditions in workspaces, as musculoskeletal disorders constitute the largest category of work-related diseases in many industrial countries .iii) Cognitive ergonomics and emotions. Experiential aspects impact on the acceptance of the system, i.e., usability, perceived safety and risk, emotions, and perception of appearance. Factors like mental workload, physical and mental stress, learnability, usefulness, efficiency, and intuitive use must be considered. Safety and perceived risk, although emotions are of great importance in this context, as are considered paramount for optimal satisfaction . In termiv) Inclusivity. The issue of inclusivity arises in the domain of robotics, where not all users can access the robots due to their diverse characteristics such as visual, hearing, motor, or cognitive limitations. The neglect of these aspects during the design, implementation or interaction phase creates accessibility barriers, preventing users with disabilities from using the robotic system .v) Multimodality. In collaborative robots, the use of multiple interfaces is common, giving rise to the need for a new list of heuristics to consider this aspect. These interfaces can enable diverse modes of communication, such as graphical, voice-based, or gesture-based communication, and they can vary depending on the type of device used . classifvi) Type of robot and functionalities. In an industrial context, robots can develop different types of actions and tasks. As  stated iWhile there are several lists of heuristics available for evaluating robotics or HMIs from different perspectives to the authors’ knowledge there is a gap in the heuristic evaluation specific to industrial HRI environments from a UX and human-centered holistic approach. Unlike experiences with concrete interfaces, collaborative robotic environments are multimodal, meaning that interaction occurs through multiple channels. As such, all these channels must provide smooth and satisfying experiences. In addition, safety is of the utmost importance in these risky environments. In this context, the robot’s behavior influences the safety, comfort, and acceptance of the person in the robotic system. In our previous works , we analTherefore, the need has been identified to create a new list of heuristics to evaluate the HRI from a UX, Technology Acceptance, and human-centered approach, which considers safety, trust and perceived safety, physical ergonomics, cognitive ergonomics and emotions, inclusivity, multimodality and types of robots and functionalities. By developing a new set of heuristics for industrial HRI environments, early-stage suggestions for improving robots can result in cost and time savings .This study aims to develop and validate a new list of heuristics to assess HRI in industrial contexts from a holistic approach and consider inclusiveness. The methodology employed in this study is based on the approach outlined by The first step aims at collecting the existing heuristics or guidelines of HRI from different databases .For this purpose, a systematic literature review was carried out. The following search equation was created. Nevertheless, each database requires the adaptation of the equation according to the differences in their functionalities, as detailed in  and (“human-robot interaction” or “hri” or “human-robot collaboration” or “hrc”)After identifying previous works, a review of the literature was performed . All relevant heuristics and design guidelines in the HRI context were collected, which initially amounted to a total of 208 tentative heuristics, as seen in Due to the complexity of the interaction, multiple topics are covered in literature in terms of heuristic evaluation and design guidelines, i.e., functionalities, interfaces, ergonomics, and so on. For this purpose, we clustered and classified all tentative sentences collected in previous step. These groups are strategically defined by their nature and implications in the interaction to easily help and guide evaluators that might use this tool see .In this step, all guidelines are redefined as heuristic as well. This step required a huge effort to perfectly capture the meaning of the evaluation sentence, since the complexity of interactions and multiple references might be merged in a single heuristic. For each sub-group, heuristics are clustered in two levels (basic and advanced), attending to the assessment complexity and how specific the aspect under evaluation is.The present study presents a preliminary list of heuristic outcomes derived from the preceding step. Nonetheless, it is necessary to evaluate the consistency of each category and subcategory and strive towards achieving balance among them. Following this initial iteration in the heuristic development process, a targeted literature review was conducted to address any identified inconsistencies. A summary of the literature used to balance the heuristics is presented in Once all heuristics had been defined as a draft, the list was presented to a group of expert evaluators. Evaluators were preselected according to their specific backgrounds and professional responsibilities or roles under inclusive premises. In summary, a total of 15 external evaluators were consulted according to their professional backgrounds. The invitations were sent via formal emails, which explained the topic of the research and the objective. Next, the expert survey (the pdf file in the dataset ) was senEach recruited expert first followed a usability study through the SUS questionnaire  that aimMoreover, the survey contained the importance rating questionnaire in the form of pairwise comparison in accordance with Analytic Hierarchy Process (AHP). This method was applied to ask the experts to grade the importance weights of each of the HEUROBOX tool’ categories: Safety, Ergonomics, Functionality, and Interfaces. These importance weights allow practitioners and researchers to prioritize which category is more important than the others, enabling them to make proper decisions in evaluating and improving human-robot systems in industrial environments. We followed the procedure of AHP provided by To enhance our research transparency, we provided the expert survey (the pdf file) and the raw data of the expert responses (the xlsx file) in the dataset .This section contains the list of heuristics generated on the basis of the literature search and their subsequent selection and clustering. As can be seen in The heuristics of Safety have been fed by the heuristics and guidelines proposed by . The SafBased on this assessment, the system should be designed to minimize hazards related to HRI in assembly settings. These hazards include general hazards related to human-assembly parts interaction, specific mechanical hazards related to human-assembly parts interaction, and specific mechanical hazards related to robot system parts falling. The system should also be free of physical features or behaviors that could cause injury, and it should include fail-safe mechanisms to ensure safety. In addition, the system should allow for the setting of trajectories to avoid contact or entrapment of human body parts, and it should include functions to limit velocities, forces, and torques. The system should also use safety-rated soft axes and have mechanisms for energy absorption and impact force reduction, as well as sensors to anticipate or detect contact and protective features against hazards associated with the workpiece. Finally, the system should include features to prevent entrapment due to moving cables or exposed parts, and it should include signaling and highlighting to alert operators to potential hazards.• The heuristics in the physical ergonomics subcategory—4 heuristics at the basic level and 25 at the advanced level - focus on the physical demands placed on the operator during HRI, such as posture, reach, and force. These heuristics aim to ensure that the operator can perform tasks comfortably and without strain or fatigue. The advanced level of assessment in this category includes additional heuristics that address more complex issues.• The heuristics in the cognitive ergonomics category—9 heuristics in the basic level and 11 in the advanced level - focus on the mental demands placed on the operator during HRI, such as attention, decision-making, and memory. These heuristics aim to ensure that the operator can effectively process information and make decisions while interacting with the robot. The advanced level of assessment in this category includes additional heuristics that consider more advanced cognitive demands, such as the ability to adapt to changing conditions and to learn from experience.The heuristics of Ergonomics are based on the guidelines and research by . The Erg• The System subcategory - 6 heuristics at the basic level and 13 heuristics at the advanced level - covers a wide range of issues, including the predictability and consistency of the interaction, the flexibility of the system in allowing the operator to customize and control the interaction, and the ability of the system to support the operator.• The heuristics in the Information subcategory—13 heuristics in the basic level and 15 heuristics in the advanced level - focus on the ways in which the system provides clear, accurate and relevant information to the operator, and that it allows the operator to access the information in a convenient and efficient manner.• The heuristics in the Task subcategory—7 heuristics in the basic level and 5 heuristics in the advanced level–aim to ensure that the system helps the operator to complete the task efficiently and effectively, without unnecessary steps or interference. These heuristics focus on simplifying various types of tasks, such as object recognition, feeding, handling and assembly, and minimizing the number of steps required to achieve goals. The heuristics also consider the ability of the system to adapt to different types of tasks and application scenarios and to allow for the reuse of previous works.• The heuristics in the Error handling subcategory - 7 heuristics at the basic level and 7 heuristics at the advanced level–focus on the system’s ability to identify and communicate errors to the operator, as well as its ability to help the operator recover from errors. This includes using visual mechanisms to indicate errors, providing clear and understandable error messages, and offering options for recovery or reversal of actions. The heuristics also consider the system’s ability to self-inspect for damages or obstacles, and to provide information about the task environment to help the operator understand the cause of errors.Assistance subcategory - 3 heuristics at the basic level and 3 heuristics at the advanced level–aim to evaluate the assistance provided by the system. It covers a range of issues related to assistance, including the ability of the system to provide clear and useful information and feedback, the use of standard rules for decision support, and the provision of context-sensitive help and documentation. Additionally, the heuristics address the importance of supporting and helping the operator to determine the most appropriate level of robotic autonomy at any given time.• The heuristics in the These heuristics in the Functionality subcategory are based on the guidelines and research by . The Fun• The basic evaluation level—28 heuristics - provides a general assessment of the UI in the HRI without considering the type of interface. These heuristics aim to ensure that the UI is easy and intuitive for the user to understand and use and that it helps the user to maintain appropriate awareness of the system’s state, follow task execution, and make informed decisions about their interaction with the robot.• The heuristics for visual interfaces—22 heuristics–aim to ensure that the user interface for the HRI system is easy to use and understand and that it presents the necessary information in a clear and structured way. These heuristics cover a wide range of issues, including the use of simple graphics and icons, the minimization of multiple windows, the use of familiar language and concepts, the usability, accessibility, and aesthetics of the interface design, the appropriate presentation of sensor information, the ability to manipulate and store displayed information, the use of efficient interaction language, and the consideration of color, contrast, and visibility in the interface design.• The heuristics for voice interface—11 heuristics - aim to ensure that the system’s voice user interface (VUI) is easy to understand and remember, efficient to use and that it provides appropriate feedback and support to the operator. These heuristics cover a range of issues, including the number of steps required in the user-system dialog, the accuracy in minimizing input errors, the natural and human-like speech, the use of efficient interaction language, and the structured dialog between the user and the system.• The heuristics for gesture—4 heuristics–aim to ensure that gestures are intuitive and natural for the user, and that can be used to control the robot’s movements or actions.• The haptic interface heuristics—6 heuristics–aim to ensure that the system is able to provide sufficient tactile feedback to the user through the use of haptic or tactile objects, and that the user is able to perceive and interpret this feedback correctly. These heuristics focus on the interpretability and perception of basic directions, as well as the tactile attributes of the objects used, such as texture, force, vibration, duration, and acceleration.The heuristics on Interfaces are based on the guidelines and research by . They arThis section focuses on presenting the validation and prioritization results performed by the experts, following the methodology defined in the previous section. As previously exposed, a total of 15 experts participated in the evaluation of HEUROBOX see , includiAs indicated by The raw data for the SUS responses can be found on the second page titled “SUS” within the dataset’s spreadsheet (the xlsx file) in the dataset . The firThe SUS comprises 10 questions, with odd-numbered questions having positive meanings and even-numbered questions having negative meanings. The positive questions are scored by reducing the user’s score by one point, while the negative questions are scored by subtracting the user’s score from 2. The total scores are then multiplied by 2.5 to obtain a range of 0–100. The mean average SUS score for HEUROBOX is 76 from experts’ perspectives. As indicated on the adjective range of SUS scores by Upon detailed examination of the data presented in Overall, the evaluation of HEUROBOX by experts was positive, as evidenced by the high average rating of 4.05 for the item “I would use HEUROBOX”. The evaluators also gave an average rating of 4 for the item “HEUROBOX was easy to use” and 3.9 for the item “I felt confident using HEUROBOX,” indicating ease of use and confidence in using the system.However, the evaluation also highlighted areas of concern among experts’ regarding the system’s complexity. For instance, the item “HEUROBOX was too complex for me” obtained an average rating of 2.1, indicating that some participants found the system challenging. The item “HEUROBOX was hard to use” also received an average rating of 1.85, further supporting that some participants struggled to use the system. Additionally, some participants indicated the need for assistance using the system, with an average rating of 1.95 for the item “I really need help from someone to use HEUROBOX.”Overall, the evaluation results suggest that HEUROBOX is a useable and intuitive system with scope for improvements in complexity and user support. The findings from the positively worded SUS items indicate a generally positive perception of the tool among the expert evaluators, with items related to ease of use and integration of various parts of the tool receiving higher scores than those related to complexity and user support. These findings can serve as valuable inputs to inform the design and development of HEUROBOX, to enhance its usability and user satisfaction.The raw data for the category-rating questionnaire can be found on the third page labeled “AHP” within the dataset’s spreadsheet (the xlsx file in the dataset ). The fiThe R codes  for execBreaking down the Safety category further, the Robot Systems subcategory received the highest weight at 0.355, followed by Motion Planning (0.353) and Organizational Measures (0.291). This suggests that in order to optimize safety, design considerations for robot systems should prioritize these areas. This result suggests that designing safe robotic systems requires a focus on the robot itself, then on its movement planning and the organization of the system. Then, Motion Planning highlights the significance of designing efficient and accurate movement algorithms for robots. Proper motion planning is crucial for avoiding collisions, navigating complex environments, and ensuring smooth and precise interactions with humans and surrounding objects. Lastly, the category of Organizational Measures is ranked in third place. Although experts have assigned it relatively less importance compared to the other subcategories, its significance should not be underestimated as it encompasses various aspects related to the organization and management of the workplace. While the focus is often placed on the technical aspects of robotics, neglecting the organizational aspects can have detrimental effects on the overall performance and safety of the system.Regarding Ergonomics, may have been ranked fourth in importance because, although it is essential to consider the HRI from an ergonomic perspective, the other categories are more critical for the overall performance and success of the robot system. It is important to note that even though ergonomics may be ranked lower in importance, it should still be given adequate attention in the design and development of robotic systems. Within the Ergonomics category, Cognitive Ergonomics was deemed more important at 0.536 than Physical Ergonomics at 0.464. This highlights the importance of designing systems that are optimized for mental workload and ease of use. It suggests that designing robotic systems that consider the cognitive aspects of HRI, such as attention, perception, and decision-making, is more critical than designing systems that focus solely on physical aspects, such as posture and movement.In the Functionality category, the Error Handling subcategory received the highest weight at 0.268, followed by Task (0.225), System (0.215), Information (0.152), and Assistance (0.140). This indicates the importance of developing robust error-handling mechanisms and defining relevant tasks for the system. The high weight assigned to the Task subcategory indicates that experts prioritize the system’s capability to carry out specific tasks accurately and successfully, highlighting the importance of designing robotic systems that are optimized for the specific tasks they are intended to perform in industrial settings. The System subcategory’s weight suggests that experts recognize the importance of designing a well-structured and integrated system. The inclusion of Information and Assistance subcategories underscores the value of providing relevant and helpful information to users and helping when needed. Nevertheless, designing systems that can effectively provide users with the necessary information and support contributes to a more intuitive and user-friendly experience, enhancing the overall functionality of the robotic system.The Interfaces category was placed third through experts’ opinions. The Interfaces category is considered important but not as critical as the Safety and Functionality categories. The experts may have prioritized the other categories due to their direct impact on the overall success and effectiveness of the robotic system. The Visual subcategory was deemed the most critical at 0.407, followed by Voice at 0.225, Gesture at 0.195, and Haptics at 0.173. This highlights the importance of developing interfaces that are visually clear and easy to understand. Visual cues and feedback play a crucial role in facilitating effective communication and interaction between humans and robots. By designing visually appealing and informative interfaces, users can easily understand and interpret the system’s status, actions, and intentions.Overall, the results of the AHP analysis provide valuable insights into the relative importance of different categories and subcategories for designing robotic systems that optimize safety, functionality, interfaces, and ergonomics. Design considerations should prioritize the areas identified in the analysis to ensure a successful and user-friendly system.The present study yielded a Consistency Ratio (CR) for each of the evaluated categories. Specifically, the general category exhibited a CR of 0.104, while the Safety category displayed a CR of 0.197. In the Ergonomics category, only one pair-wise comparison was conducted, thus rendering a NaN value for the CR. Meanwhile, the Functionality category demonstrated a CR of 0.129, and the Interfaces category exhibited the lowest CR of 0.104. Although  allows aIn current literature, to the authors’ knowledge, there is a gap in the heuristic evaluation of HRI in industrial environments from a UX and human-centered design perspective. Thus, a holistic and human-centered approach is lacking, as the literature has been largely “robot-centric” up to this point . To achiTherefore, HEUROBOX is a novel heuristic evaluation tool proposed for assessing the degree of alignment between the robot and contextual features with human needs to facilitate efficient and satisfactory interactions in industrial settings. The tool comprises four categories: Safety, Ergonomics, Functionality, and Interfaces. The basic level of HEUROBOX encompasses fundamental aspects of HRI evaluation and incorporates 84 heuristic principles. On the other hand, the advanced level comprises a range of specific elements or functions and includes 228 heuristic principles, including those at the basic level. It is important to note that evaluating each category is crucial for holistically ensuring a seamless and satisfactory experience.HEUROBOX, as a comprehensive heuristic evaluation tool, has been specifically designed to fulfill the requirements outlined in Usability evaluation through expert assessments of the HEUROBOX tool has obtained favorable results, indicating the effectiveness of the tool in assessing the quality of HRI in industrial settings. The positive outcomes from the usability evaluation of HEUROBOX indicate that it is a promising approach for ensuring that HRIs are efficient and satisfactory. Moreover, the general index of 76 obtained from the usability evaluation highlights the potential for HEUROBOX to provide a comprehensive evaluation of the quality of HRI, considering various factors such as safety, ergonomics, functionality, and interfaces. These findings support the use of HEUROBOX as a valuable tool for evaluating and improving HRIs in industrial settings from a human-centered perspective.The findings discussed above provide valuable insights for designers and developers in prioritizing their design efforts to optimize critical aspects of HRI. Designers can leverage these results as a guide to focus on key areas that have been identified as important by experts in the field. For instance, the experts’ responses, obtained through applying the AHP, indicate that Safety is the most critical general category, followed by Functionality, Interfaces, and Ergonomics. The focus on safety is especially important in robotic systems that interact with human beings, such as collaborative robots, as these systems are required to be safe and reliable for working alongside people. Nevertheless, safety is one of the most studied aspects of industrial robotics, and there are numerous standards that robots must comply with to ensure safety aspects .The high weight assigned to the Robot Systems subcategory within the Safety category emphasizes the significance of considering the robot itself when designing safe robotic systems. This insight suggests that designers should pay careful attention to the robot’s construction, functionality, and inherent safety features to minimize risks and ensure user wellbeing. Similarly, the prioritization of error-handling highlights the need for robust mechanisms to handle errors or failures that may occur during system operation. By implementing effective error-handling strategies, such as error detection, recovery, and fault tolerance, the reliability and performance of the robotic system can be enhanced. As well as the emphasis on the Visual subcategory implies that designers should prioritize creating visually appealing and intuitive interfaces. This insight emphasizes the significance of clear and informative visual cues in facilitating effective communication and interaction between humans and robots.By utilizing these insights, designers, and developers can allocate their resources and efforts strategically, focusing on the critical aspects identified by experts. This approach ensures that the HRI is optimized for safety, functionality, ergonomics, and interfaces, leading to improved UX and higher user acceptance and overall wellbeing. Overall, the results discussed in this study provide practical guidance for designers and developers, enabling them to prioritize design efforts and optimize their systems for critical aspects of HRI.In the field of HRI in industrial settings, the evaluation of UX and technology acceptance of the systems is crucial. In this sense, HEUROBOX provides a structured approach to evaluating HRI, allowing researchers, developers, or practitioners to systematically identify and assess the effectiveness of different aspects of the interaction in a quick and cheap way.HEUROBOX provides a framework for evaluating robotic systems that are both comprehensive and systematic. Using this set of heuristics allows evaluators to identify a wide range of potential usability issues that may otherwise be missed. Additionally, the systematic nature of HEUROBOX ensures that all aspects of the HRI are considered, including both the technological and human factors involved.Heuristics can provide valuable insights into the UX of collaboration, helping researchers and designers understand how people perceive and interact with robots. Like other heuristic evaluation tools, HEUROBOX can be used iteratively throughout the design process . FurtherWhile HEUROBOX can provide a precise evaluation of HRI, it also has the limitation that the evaluator must have a good understanding of the specific robot being studied. This is because HEUROBOX includes a set of detailed heuristics that require precise knowledge of the features, functions, and capabilities of the robot in question. However, this limitation can also be seen as a strength, as it allows researchers, developers, or practitioners to carry out a very specific and targeted evaluation of the HRI. Ideally, the evaluators involved in the heuristic evaluation should have a multidisciplinary background, encompassing expertise in HRI and UX. The diverse expertise ensures a comprehensive evaluation, considering both technical aspects of the system and the human factors. Heuristic evaluations sometimes could be subjective and rely on the expertise and experience of the evaluator, which can introduce bias and variability into results. Also, it can be perceived as time-consuming and labor-intensive for the evaluators. These considerations highlight the need for careful planning, execution, and interpretation of heuristic evaluations in HRI to obtain valid and meaningful results.It is widely recognized that UX is influenced by a multitude complex factor, and individual factors play a crucial role in evaluating experiences . DespiteRegarding multimodal interactions, which involve the integration of multiple sensory modalities for more natural communication with robots, have the potential to create powerful user interfaces and channels of interaction. While the proposed list of heuristics is applicable to different types of interfaces and, therefore, to multimodal environments, there may be overlap among the heuristics proposed within the subcategories of the Interfaces section. This overlap could lead to a situation where a robot agent with two types of interfaces may appear to fulfill a lower percentage of heuristics. However, when these two interfaces complement each other effectively, the overall level of interaction may improve accordingly. Therefore, it is important to consider that the evaluation of interfaces in a multimodal context requires a nuanced approach. The overlap among heuristics should be carefully examined, taking into account the interplay between different modalities and how they contribute to the overall UX.Despite these limitations, HEUROBOX has the potential to provide a precise evaluation of HRI. Its detailed set of heuristics requires evaluators to have a good understanding of the specific robot being studied, but this limitation can also be seen as a strength, as it allows for a specific and targeted evaluation of the HRI. By using HEUROBOX in conjunction with other evaluation methods, evaluators can gain a comprehensive understanding of the strengths and weaknesses of the robot in question. Moreover, by using HEUROBOX to evaluate different robots or different versions of the same robot, evaluators can compare the results across different scenarios and identify patterns or trends over time, providing valuable insights into the progress of robot development.• Safety is a critical aspect of HRI, and it encompasses a range of design considerations aimed at preventing harm to both humans and robots. These include safety measures such as emergency stops, safety barriers, and collision detection systems. Additionally, the design of the robot should take into account the physical and cognitive limitations of the users and be able to adapt to unexpected situations.• Ergonomics is concerned with the interaction between the user and the robot, taking into account factors such as posture, movement, and comfort. The design of the robot should ensure that users can operate it without experiencing undue physical strain or discomfort.• Functionality is a key aspect of the robot’s design, as it determines the robot’s ability to perform the intended tasks efficiently and effectively. The functionality of the robot should be tailored to the specific context of use and should be able to handle any unexpected situations that may arise. The robot should also be able to perform tasks autonomously, with minimal human intervention, if necessary.• Interfaces are a crucial category in HRI design, as they define the communication channels between the user and the robot. Interfaces encompass a range of design considerations, including visual, voice, gesture, and haptic interfaces. Visual interfaces should be designed to provide the necessary information in a clear and structured way, with simple graphics and icons. Voice interfaces should be designed to be natural and human-like, with structured dialog between the user and the system. Gesture interfaces should be intuitive and natural for the user to use, while haptic interfaces should provide sufficient tactile feedback to the user.The increasing number of robots being incorporated into industry highlights the necessity to have natural, fluid, and satisfying interaction between humans and robots. This paper presents a contribution to a new evaluation list through a set of heuristics to assess HRI. It is a tool that facilitates the evaluation of HRI and allows the identification of aspects for improvement in the system in terms of UX. However, in order to obtain a complete and real evaluation of the UX, it is appropriate to complement it with other UX evaluation techniques, such as usability tests. HEUROBOX consists of four principal categories: Safety, Functionality, Ergonomics, and Interfaces.While these four categories are distinct, they are closely related, and each has an impact on the other. For example, safety is closely related to ergonomics, as a robot that is ergonomically designed is less likely to cause harm to the user. Additionally, functionality is closely related to interfaces, as the interfaces must be designed to enable the robot to perform its intended tasks efficiently and effectively. Finally, the UX and technology acceptance will be impacted by all four categories, as the robot’s safety, ergonomics, functionality, and interfaces will all influence how the interaction is perceived.Depending on the complexity of the robotic system itself, the level of heuristics to be met may be different to generate a satisfactory experience. That is, a simpler system may meet only the Basic level of heuristics and generate a satisfactory experience, and a more complex system may meet also the basic Level of heuristics but still generates a frustrating experience for the user. That is why we also propose the Advanced Level, so it is the expert who must choose which is the most adequate for the robot to be studied. Nevertheless, it is proposed to make a holistic assessment when evaluating the UX in HRI, so that it considers the characteristics of the user, context, and system in an objective and subjective way, before, during, and after the interaction. Furthermore, it would be necessary to validate and correlate the level of fulfillment of the heuristics with the level of satisfaction and acceptance perceived by the users during the interaction.As a future line, it would be interesting to establish a classification/standard based on the complexity, characteristics, functionalities, and objectives of the robot, in order to determine the level of heuristics it must meet. By creating such a system, organizations and designers could ensure that robots are designed and evaluated in a consistent and comprehensive manner, allowing for more effective and efficient interaction between humans and robots. This would also provide a clearer understanding of the capabilities and limitations of different types of robots, allowing for more informed decisions regarding their use and deployment in various industries and contexts. Ultimately, such a classification/norm would contribute to the continued development and improvement of HEUROBOX, as it would serve as a framework for evaluating and designing robots that are tailored to meet the needs and expectations of their human collaborators.In order to comprehensively evaluate and design multimodal interfaces, it is imperative to carefully consider the distinctive requirements and characteristics associated with each modality within the specific context of the robot under evaluation. The evaluation process should primarily focus on assessing the robot’s ability to enable seamless communication and interaction across different interfaces. In this regard, HEUROBOX should enhance the multimodality section of the list by placing particular emphasis on the extent to which the combination of different interfaces effectively complements one another and contributes to substantial improvements in overall interaction and UX.Also, the ethical implications of robots are becoming increasingly important. While robots can bring many benefits, they can also pose ethical challenges. In this regard, a future line of research could involve the development of an “ethical” category that would allow for the evaluation of whether the characteristics of the robot and context are ethical.To finish with, our study acknowledges certain limitations that should be taken into account. Firstly, the selection of databases, although designed strategically to encompass a broad range of relevant publications, may have inadvertently excluded important articles from contributing to the research outcomes. Additionally, the selection and clustering of heuristics were subject to the researchers’ interpretation of the literature, potentially introducing bias despite efforts to mitigate it. Despite these limitations, our study provides valuable insights into the topic and serves as a foundation for future research in the field of multimodal interactions and interface design.


A survey was carried out to assess challenges and communal farmers' views on cattle production. In Ga-Matlala, 59 community cattle farmers from three rural villages were interviewed . The majority of responders (49.2%) were from Madietane, with an equal number (25.4%) from Phetole and Phofu (25.4%). In all three villages studied, males outnumbered females, with the majority of responders aged 55 and older. In all selected villages, the majority of respondents were cattle owners with 16 years or more of farming experience. Secondary school was the most frequently reported educational background in Phetole and Phiofu, while primary school was the most frequently reported in Phofu. According to the findings, the most common cattle breed owned in Phetole and Phofu was Nguni, while Afrikaner was the most common in Madietane, and the most common reason for keeping cattle was income in the study areas. The most frequently mentioned challenges in the areas are sickness (Soft hooves/or lumpy skin disease/or red water/or tick-borne disease), stock theft and disease, with Madietane having the highest mortality rate, followed by Phetole and Phofu. The most commonly reported perceived solutions were government assistance in terms of vaccinations/or veterinarians, dumping sites/or fixing water machines/or provide dams/or supplements, feed/or full-time patrollers to protect cattle from being stolen; and the purchase of cattle medicines. The majority of farmers in the selected villages can buy medicines for their cattle, while those who cannot say that the government assists them with vaccinations. As a result, it is concluded that there is a need for more knowledge and information on the subject. LivesCommunal cattle farming is one of the world's oldest farming systems, practiced mostly by rural households in developing countries, particularly in Africa, and appears to be extremely resilient to any global economic crises to date . Cattle Cattle production in the subtropics is hampered by climatic stress, nutritional stress, and disease, as well as insufficient access to land and water, a lack of market channels, poor rangeland management, and a lack of feed resources . As a re22.1The research was carried out in three communal areas in the Capricorn District Municipality of South Africa's Limpopo province. Phofu, Phetole, and Madietane were the three communal areas . PolokwaSource: Monkwe, TR. 2021. Map of Phofu, Phetole, and Madietane villages in Ga-Matlala area.2.2The survey was conducted with a total of 59 respondents in the three combined selected rural areas . Participated respondents were 15 from Phetole, 15 from Phofu and 29 from Madietane areas. The small size and imbalance of farmers in the areas was because of Madietane had more cattle farmers than Phetole and Phofu and the unwillingness to continue with interviews. Each individual local Induna of each of the three villages  was visited prior to data collection day to request permission to collect data and the letters of request were provided.2.3Section A captured data on household demographic information, Section B included herd size and management of cattle, Section C included farmers’ opinion on the challenges of cattle farming in the area.Snowball sampling technique also known as referral sampling was used to select 59 households that were interviewed in the three villages. The questionnaire was pre-tested before use in the survey to check its suitability. This was done to identify ambiguous questions. The respondents were interviewed at their homestead with pre-tested structured questionnaire. The interviews were conducted in the Sepedi vernacular by trained enumerators. The questionnaire consisted of four sections labelled as A, B, and C 2.4Data were analysed using Statistical Package for the Social Sciences version 27 . Chi-square (χ2) statistics were used to compare categorical variables between three villages. P- value was considered significant different at 95% interval (P < 0.05).33.1All demographic characteristics of the respondents  did not 3.23.33.43.544.1In the current study, men made up the vast majority of respondents. This could be attributed to men's role in cattle management activities such as daily herding of cattle to grazing areas. Similar findings were reported by Ref. , who disThe majority of farmers in this study were above the age of 54, indicating that elderly individuals are certainly involved in cattle farming in Ga- Matlala's areas with free communal grazing land. The findings of this study show elders have more time to care for cattle in rural areas than young people who reside in cities due to employment and school. Similar results were reported in Eastern Cape by Ref.  who statThe majority of farmers in the three villages had 16 years or more of experience farming with cattle. This is consistent with the fact that older people are more involved in cattle farming than younger people. This result is in line with the findings of  who obseIn the present study, high school was reported to be the highest educational level obtained by majority of the farmers in Phetole and Madietane while primary school was reported in Phofu. This result is a major advantage for the integration of communal area farmers into beef cattle value chain development projects. This finding was also unexpected in light of the number of older participants in the study area who depend on pensions for their income and who grew up in the apartheid era and had limited access to formal education . These f4.2In the present study, majority of the farmers reported large herd size in Madietane and Phetole. According to Vetter et al. (2020), larger herds suffer lower mortality rates, suggesting that owners of larger herds have better means to support their herds and owners of larger herds are wealthier and have more access to inputs and herding labour. This is comparable with studies that reported large herd size ,32,33. OAll of the farmers surveyed raised cattle that were either Afrikaner, Nguni, Brahman, crossbred, or a combination of the above breeds. However, most farmers in Phofu and Phetole indicated that they preferred to keep Nguni breeds, whereas in Madiatane, the most popular breeds were Afrikaner, Nguni, and Afrikaner. This could be owing to these breeds' ability to produce and their increasing tolerance to rural conditions . found sCattle are normally freed in the morning and herded to the grazing areas, returned home later, and kraaled at night in the three villages. However, most farmers in Phetole and Madietane reported that even though they let cattle graze during the day and kraaled at night, they still provide them with feed, water, and medication when they return home later, whereas most farmers in Phetole reported that cattle rely on community water, so they do not provide them with food or water when they return home . observe4.3The study found no significant differences in the reasons for keeping cattle between the three villages. However, cattle serve multiple purposes in the communities studied. In Phetole and Madietane, income was the most important reason for having cattle, while in Phofu, income and inheritance were the most important reasons. Cattle farming is considered by communal farmers to be the most lucrative business. For instance, if a child is required to attend school and a school fee is required, the farmer cannot sell any other livestock than cattle because they believe that selling cattle will swiftly bring in a large sum of money and allow him to pay off the debts . reporte4.4The study discovered that stock theft was the most significant challenge in the three villages studied. Cattle are regularly stolen in these villages in the grazing areas because famers leave the cattle with no herders on the grazing fields. These findings are consistent with those of , who rep4.5According to the findings of the study, the majority of farmers in Phetole and Phofu reported receiving government vaccination assistance. This indicates that the majority of farmers rely on government help to keep their cattle healthy. This is consistent with the findings of , who fou5Findings from this study revealed that farmer's knowledge on issues such as herd size, cattle breeds in the herds, cattle management, reasons for keeping beef cattle and reasons for loss of cattle has been successfully evaluated in Ga-Matlala area, Limpopo South Africa. It was noted that the majority of respondents were males. Since most of the farmers are old people, it was expected that there will be the highest number of respondents who never attended school, however, high school and primary school were the highest educational background which means most of the farmers are literate and can be able to help themselves in most challenges related to beef cattle farming. Not only they depend on educational background, but farming experience also play a very important role in knowledge of beef cattle management, hence majority of beef cattle farmers have more than 16 years of farming experience.The herd size was larger in the villages, this makes it difficult for them to manage their herds particularly when they are faced with challenges such as dry season when there is a shortage of feeds. Most of the farmers farm with Nguni and Afrikaner breeds, this is also an advantage since these breeds can survive harsh conditions, therefore can survive the dry season challenges. Highest mortality rate was reported in one village and disease was reported as the main cause of cattle mortalities, this can imply that most of the farmers that reported poor educational background may be those facing challenges and only less of those reported better educational background face these challenges. Another challenge that was mostly reported was cattle theft, this may be because of ignorance of farmers as they tend to leave cattle unattended at the grazing fields. However, solutions to the mentioned challenges need the government to assist. Regarding the daily cattle management, it is common in communal areas that livestock is released to grazing fields and brought home late, but provision of extra water and feeds is optional. Income was the most reason to keep cattle, this can be expected from each cattle farmer. Most of the farmers are able to buy medicines but others are not able to buy medicines. This means those that are not able to buy medicines rely on the government and if the government is not providing then their cattle production suffers because of disease. Moreover, farmers that are not able to buy medicines for their cattle have no money to buy or no knowledge on the medicines needed on the health of cattle, hence, they rely on the government. It is thus concluded that there is a need for more knowledge and information on the overall cattle management which will assist by reducing mortality rates and overcome several difficulties they reported, particularly with regard to disease management and theft for enhancing productivity in the communal areas.5.11Encourage knowledge creation and sharing among farmers2Public and private sector support for infrastructural developmentDecentralized information management and sharing of appropriate knowledge using new technologies such web-based applications like management database systems is encouraged. Such systems encourage farmers to identify, share and prioritise their problems and needs but most importantly, to seek ways of solving their problems within their community rather than waiting for the government's extension service. The database will also, not only serve as an information sharing platform but for record keeping as it is capable of producing documented decisions based on accessible and reproducible knowledge. For sustainability of the system, farmers should be asked to pay an annual fee for the maintenance and upgrading of the systems.It is important for the government to strengthen public-private partnership in financing the establishment of production and marketing infrastructure in the communal farming communities. Multi-stakeholder cattle farming development forums targeting emerging and communal farmers at local and district municipalities as well as provincial level could be a good way to foster these linkages or partnerships. Such forums should then be used in identifying the appropriate infrastructure and proposed locations for the benefit of the farmers. Investment in production infrastructure will improve productivity and cushion some of the challenges reported in this study. These include theft, disease and predators. On the other hand, availability of marketing infrastructure will significantly improve the ability of farmers to reduce transaction costs, improve market access and access to market information.Thapelo Rosina Monkwe: Performed the experiments; Analysed and interpreted data; Wrote the paper.Masibonge Gxasheka: Conceived and designed the experiment; Contributed reagents, materials, analysis tools or data.Busisiwe Gunya: Conceived and designed the experiments; Analysed and interpreted the data; Wrote the paper.National Research Foundation [MND190909475603].Thapelo Rosina Monkwe was supported by Data will be made available on request.The authors declare no competing interests.


Although data on the completeness and timeliness of monthly surveillance data are collected in the District Health Information System-2 (DHIS2), they have not been routinely analyzed. We assessed completeness and timeliness of monthly outpatient department (OPD) data, January 2020-December 2021.th day of the following month) divided by reports received. Completeness or timeliness score of <80% was regarded incomplete or untimely.we analyzed secondary data from all the 15 regions and 146 districts of Uganda. Completeness was defined as the number of submitted reports divided by the number of expected reports. Timeliness was defined as the number of reports submitted by the deadline  and 2021 , as was the median timeliness . Kampala Region was the only region that consistently failed to reach ≥ 80% OPD timeliness . Nakasongola was the only district that consistently performed poorly in the submission of timely reports in both years .there was an overall good performance in the submission of complete and timely monthly OPD reports in most districts and regions in Uganda. There is a need to strengthen the good reporting practices exhibited and offer support to regions, districts, and health facilities with timeliness challenges. Timely and complete reporting of routine public health information about diseases and public health events are important aspects of a robust surveillance system . ThroughThis interchange and transfer of data from paper into the DHIS2 likely caused distortions in terms of accuracy, timeliness, and completeness . The DHIStudy setting and design: we conducted a descriptive quantitative study that involved analysis of monthly OPD disease surveillance reports submitted to the DHIS2 from January 2020 to December 2021. Uganda has 146 districts which are distributed across 15 regions as designated by MoH. These are; Acholi, Ankole, Bugisu, Bukedi, Bunyoro, Busoga, Kampala, Karamoja, Kigezi, Lango, North central, South Central, Teso, Tooro and West Nile. The health care system has several governments and privately owned health facilities which are organized in a hierarchical order [al order . At the Data source: we extracted data from the DHIS2 from all the regions of Uganda which comprise the 146 districts. The DHIS2 is a web-based open-source health management information system used to collect aggregate data which is routinely generated across health facilities [cilities . The DHIGeneration of monthly surveillance data: routine monthly surveillance data are generated at the community through surveillance activities carried out by the VHTs. The disease surveillance reporting system follows a hierarchical order from the community level to the national level through the DHIS2. At the health facility level, information is first collected as patient-specific data using paper-based IDSR surveillance tools and later transferred into the electronic format-the DHIS2 as aggregated data. The monthly OPD report is an aggregated report for all OPD occurrences at each health facility. It contains data on OPD attendances, referrals, diagnosis, infectious disease and epidemic prone diseases, non-communicable diseases, maternal and child health, family planning, and immunization services. The IDSR defines completeness as the proportion of reports submitted divided by the number of expected reports from the same health facility, district or region in a given time period while timeliness is defined as the proportion of reports submitted by the deadline divided by actual reports received in the given time period. Health facilities are expected to submit complete monthly reports by the 15th of the following month. The facilities with percentages below the 80% target, are regarded as having submitted incomplete or untimely reports. Data from different health facilities are sent to the district and then later merged into regions constituting different districts.Data abstraction and analysis: we captured different variables for the years 2020 and 2021. These years were considered because we wanted to evaluate the immediate past performance trends of the reporting indicators especially during the advent of COVID-19. A data abstraction form was used to extract information on the expected number of reports, actual number of reports and actual number of reports on time. It is from these variables that the monthly completeness and timeliness were computed. Completeness was calculated as the number of actual monthly OPD reports received divided by the expected number of reports in a given year and expressed as a percentage. Timeliness was calculated as the number of actual monthly OPD reports received on time (by the 15th of every month) divided by the expected number of reports in a given year and was also expressed as a percentage. We determined the overall proportions of completeness and timeliness of reporting by year at national, regional, and district levels, level of health facility, and health facility ownership. We analyzed data using Epi-info version 7.0 .Ethics approval and consent to participate: because our study used routine surveillance data reported by health facilities in the DHIS2 which were also aggregated with no individual patient identifiers, we did not seek for ethical approval. However, we sought permission to use the data from the Uganda MoH. The US Centers for Disease Control and Prevention (CDC) also provided the non-research determination (NRD) for non-human subjects. Data were only accessed by the study team.Overall, in 2020 the expected number of reports was 69,468 and of these, 68,935 reports were submitted and 52,430 were submitted in time corresponding to 99.2% completeness and 75.5% timeliness. In 2021, the expected number of reports of was 69,659 and of these 61,490 were submitted in time corresponding to 99.8% completeness and 88.1% timeliness. The median completeness of facility OPD reports was high in 2020  and 2021 , as was the median timeliness . There was a general improvement in reporting in terms of completeness and timeliness from 2020 to 2021. This trend is similar across all regions, level of health facilities, and type of ownership of health facility. Regarding completeness, all regions scored above the required reporting target of 80% in 2020 and 2021. However, 7 out of 15 regions did not reach the timeliness reporting target in 2020 and in 2021, only Kampala region did not score above the timeliness target. Kampala region was the only region which consistently failed to meet the 80% timeliness target in both years . All levels of health facilities scored above the required completeness target in both years. National referral hospitals were the only facilities that consistently failed to meet the timeliness target in both years . Privately owned health facilities failed to score above the required timeliness target in 2020. Although they improved and scored above the timeliness target in 2021, they still performed poorer than government owned facilities .District monthly completeness and timeliness of outpatient department reports, Uganda, 2020-2021: in 2020, all districts scored above the recommended target for completeness except Namisindwa while in 2021, all districts scored above the required target (d target . In regad target .In our analysis of the monthly disease surveillance reporting data, we found that there was good performance in completeness and timeliness of reporting. In 2020, half of the regions did not submit reports in time. Kampala Region was the only region which consistently failed to reach the timeliness target in both years. At district level, Nakasongola District was the only district which consistently failed to score the timeliness target. Additionally, higher level health facilities like national referral hospitals and referral hospitals performed poorer than lower-level health facilities in terms of submission of timely reports. This study addresses the importance of monitoring routine surveillance data especially that which is collected on a monthly basis for public health action and monitoring performance. There was good performance in completeness and timeliness of reporting. This is due to regular mentorship and improved capacity of district biostatisticians and data personnel to collect and submit disease surveillance data . AdditioOn the other hand, a systematic review done on task shifting in sub-Saharan Africa recognized that although it is cost-effective, it has a risk of competing with other health service priorities . Task shLimitation: our study only utilized DHIS2 information in the years of 2020 and 2021. We did not analyze reporting rates for a longer duration of time that is, the years before 2020. This could have allowed us ascertain the true reporting trends over the years. We intended to analyze reporting rates during the COVID-19 pandemic to ascertain if surveillance data reporting was affected since the health system was affected during this period. Our study has a strength that it utilized disease surveillance data which were collected from the whole country.There was good reporting in terms of completeness and timeliness in both years. However, despite the good reporting, timeliness of reporting was low in Nakasongola District, Kampala Region and higher-level health facilities. We recommended strengthening the practices leading to good reporting and offer support to health facilities with challenges to timeliness through mentorships and continuous support supervision. Further studies are needed to understand and identify barriers to timely reporting.Timely and complete reporting is an important aspect in disease surveillance as it helps in timely detection of disease outbreaks and public health events;There are challenges faced by low resource settings especially in Africa in submission of timely and complete disease surveillance data and later on its utilization;The integrated disease surveillance and response guidelines currently recommend that for a report to be timely, 80% of the reporting units must have submitted in time and for a report to be complete 80% of the expected reports should have been submitted.The study demonstrates the need for periodic analysis of routinely collected surveillance data to facilitate planning and decision-making;The results show that there was good performance in submission of monthly diseases surveillance data, this is in contrast to other studies which looked at submission of weekly reports where there was poor performance;The study opens an opportunity for future studies that need to investigate why there is good performance in submission of monthly reports yet there is poor performance in submission of weekly reports.


Exergaming, or technology-driven physical exercise, has gained popularity in recent years. Its applications include physical education, health promotion, and rehabilitation. Although studies have obtained promising results regarding the positive effects of exergaming, the outcomes of exergaming for different populations remain undetermined. Inconsistencies in the literature on this topic have multiple potential explanations, including the content and demand of the exergames and the capability of the exergamer. A model with a sound theoretical framework is required to facilitate matching between games and gamers. This article proposes a relational model based on a matrix of Bloom’s taxonomy of learning domains and the performance components of exergames. Appropriate matching of the physical demands of an exergame and the ability of the exergamer would enhance the effective usage of exergaming for individuals with various needs. This theory-based exergame model is developed to promote the general development, physical status, and psychosocial well-being of students, older adults, and individuals with rehabilitation needs. This model may provide a resource for future research on the application, effectiveness, and design of exergaming. Exergaming has recently gained popularity among children and adolescents . A surveExergaming combines exercise and gaming and can also be called active video gaming. Advances in digital gaming technology have enabled a player’s body movements to replace the button presses of traditional sedentary gaming. Video gaming technology has advanced from motion-sensing handles to optical sensors that allow for more realistic whole-body movement. This development has prompted researchers to explore the potential applications of exergames and active video games in physical education , health The present study defined exergaming, reviewed current research findings on its effects on different population groups, and recommended further research on its optimal use as an educational and physical exercise tool. We argued that exergaming is a beneficial tool that can (1) increase the level of physical exercise of the general public, (2) promote learning and physical education in students, and (3) facilitate rehabilitation. These purposes can be better achieved if the demands of exergames complement the player’s ability. Therefore, this study proposes a model with a multidimensional perspective to ensure precise matching of the demands of an exergame and the player’s ability.One of the most widely recognized benefits of exergaming is its promotion of physical activity in children and adolescents . The groExergaming was demonstrated to improve children’s executive functioning . One stuMany exergamers experience enjoyment when playing. In addition, exergaming, as an alternative form of physical exercise, promotes psychological health. A study revealed that exergaming significantly improved reaction time, subjective happiness, and mental well-being in young adults . AnotherTraditional video games also have significant positive effects on multiple health-related outcomes. One review indicated that sedentary video games improved 69% of psychotherapy outcomes, 59% of physical therapy outcomes, 50% of physical activity outcomes, 42% of health education outcomes, 42% of pain control outcomes, and 37% of disease self-management outcomes . AlthougAlthough considerable evidence indicates that exergames enhance physical and psychosocial health in children, some researchers hold opposite opinions. A naturalistic study investigated whether children playing a new exergame spontaneously engaged more in physical activity than those playing a sedentary game; the evidence did not indicate that children playing active video games were more active in general . This reA review of 14 descriptive studies, one uncontrolled trial, and two pilot randomized controlled trials concluded that evidence remains mixed on the subject. No adequately powered randomized controlled trial has assessed the long-term effects of exergaming on children’s health .These drawbacks may not result from exergaming itself but from the selection of exergames. The content and difficulty level of a game may result in improper matching with the gamer’s ability, which may affect the usage of exergaming.Exergames are interactive and provide physical exercise and workouts rather than promoting the behaviors  of traditional sedentary video games. Thus, whether exergames also produce the negative effects of conventional video games remains unclear. Although studies have reported the negative effects of video games, no studies are known to have reported the adverse effects of exergaming.Some authors have contended that employing video games as a learning mode can be more enjoyable and stimulating than traditional modes of teaching and learning . TeacherEmpirical research on why and how games affect students is essential as exergaming gains attention and popularity in education. Therefore, the present study constructs a classification system for exergames to facilitate future research and to effectively incorporate exergaming into educational contexts.Studies have classified video games by function, form, and genre . SolomonThe Exergame Network, an international collaboration of health and fitness practitioners, exergame developers, and researchers, proposed the following five basic types of exergames: (1) workout exergames—the player completes a workout based on the advice of the game; (2) control exergames—the player uses different body parts to control the game; (3) exergame machines—the player uses real fitness equipment to play the game; (4) sensory exergames—the player must jump and run to earn points; and (5) rhythm exergames—the player becomes a musician or dancer and is guided by music . This syExergames must be individualized and tailored to the target population to yield the greatest benefit . BecauseA growing number of scholars have recommended using exergame learning applications, particularly in physical education . LearninBy including all three domains in education planning, it is able to create a holistic approach to learning that addresses not only the intellectual but also the emotional and physical aspects of student development. This can lead to a more comprehensive and effective educational experience for learners .The present study employs Bloom’s taxonomy as a framework to analyze the effects of exergaming on exergamers . The priSubdivision of the learning domains can provide a detailed framework for the analysis of exergame demands .The ability to control voluntary muscle movement is critical to motor development. Motor skills are generally divided into gross and fine skills; gross motor skills involve the use of large muscles in the arms, legs, and torso, and fine motor skills involve the precision, dexterity, and coordination of the hands and fingers . The motCognitive development, evidenced by one’s ability to think and understand, results from information processing, concept formation, perceptual skills, language learning, and other brain functions . The cogSocial development reflects a child’s ability to interact with peers and adults in a socially acceptable manner. Video gamers are not confined to an isolated console but are connected to many other gamers worldwide through the Internet . This teMore vigorous research studies are required because of the growing interest in exergames as educational and rehabilitation tools. Although adverse effects of exergames have not been reported, exercising caution is crucial in the developmental stage. Notably, when adopting exergaming as a teaching and learning tool, the demands of the exergame should be carefully matched with the player’s motor, cognitive, and social abilities. The present study’s proposed classification system may inform pedagogical practices and provide insight into the integration of exergaming and education. In addition, this model may provide an essential reference for future exergaming regulations prior to its inclusion in education curricula.Undeniable differences are present between real sports and exergaming. Replacing real sports with exergaming for children requires careful contemplation. The proposed classification system may guide the systematic study of the effects of exergaming and the dissimilarities between real sports and the sport-like activity of exergaming. Many advancements may be made in exergaming hardware and software, and systematic studies of the effects of exergaming should guide such advancements.The proposed system may contribute to the subsequent development of a standard-level classification system, which can ensure the positive and healthy growth of exergaming. Until now, the adverse effects of exergaming remained unexplored; this study discussed both the positive and negative effects of exergaming on the health and well-being of children. Relevant studies have revealed a trend in the increased use of exergames in the educational context.This article summarizes the benefits of exergaming on gamers’ physical and psychosocial well-being. Although the potential benefits of exergaming have been reported, selecting suitable exergames to match the needs of gamers is crucial to optimize these benefits. This study proposed a model based on a matrix of learning domains, the performance components of exergames, and the matching of the exergame demands with the ability of the exergamer. Based on Bloom’s taxonomy  of learnAn exergame analysis is essential to maximize the benefits of exergaming with respect to rehabilitation and training. A wide variety of highly individualized exergames are commercially available and include multiple therapeutic elements. This study adopted a learning perspective framework to analyze the contents of exergames for multiple reasons. First, exergames have been widely employed to enhance children’s physical, cognitive, and mental functioning. An analysis based on a learning perspective is therefore appropriate. Second, for different populations, exergaming can be considered a growth process through which the gamer acquires skills to enhance their overall well-being. Thus, a developmental evaluation would be most appropriate for assessing exergame types.Finally, the appropriate matching of gamers and exergames may determine the efficacy and effectiveness of exergame training. Some contradictory findings regarding the effectiveness of exergaming are believed to have resulted from inappropriate matching between the needs of gamers and the demands of exergames. Therefore, the proposed theoretical framework for the use of exergames can help maximize the benefits of exergaming.DC contributed to the conceptual design and model development. SM contributed to the model development and preparation of the manuscript. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


This review paper presents an overview of the state of the art on process-induced degradation of poly(lactic acid) (PLA) and the relative importance of different processing variables. The sensitivity of PLA to degradation, especially during melt processing, is considered a significant challenge as it may result in deterioration of its properties. The focus of this review is on degradation during melt processing techniques such as injection molding and extrusion, and therefore it does not deal with biodegradation. Firstly, the general processing and fundamental variables that determine the degradation are discussed. Secondly, the material properties  are presented that can be used to monitor and quantify the degradation. Thirdly, the effects of different processing variables on the extent of degradation are reviewed. Fourthly, additives are discussed for melt stabilization of PLA. Although current literature reports the degradation reactions and clearly indicates the effect of degradation on PLA’s properties, there are still knowledge gaps in how to select and predict the processing conditions that minimize process-induced degradation to save raw materials and time during production. Plastics play an essential role in today’s society, since they are low-cost, lightweight, versatile, and easily processable materials that possess excellent mechanical, barrier, and aesthetic properties ,2,3. ConBecause most plastics are based on non-renewable resources such as crude oil or natural gas, the increasing demand has resulted in both environmental and economic consequences: the massive accumulation of mainly non-degradable plastic waste in nature , the conBioplastics can be biobased, biodegradable, or a combination of both . BiobaseIn 2022, global bioplastic-production consisted of 20.7% of PLA , making The polymer backbone of PLA is produced from the monomer lactic acid, a fermentation product of sugar feedstock that occurs in two optically active enantiomers, namely L-lactic acid and D-lactic acid , illustroperties , a largeoperties ,26.The same ester groups in aliphatic polyesters that are responsible for biodegradation, are vulnerable linkages during melt processing . TherefoThermoplastic polymers such as PLA need to be converted from simple granules into more complex consumer products by using well-established polymer processing technologies such as extrusion and injection molding . Before The major technique for melting thermoplastic polymers is screw extrusion . A screwAlthough screw extrusion is a continuous process, injection molding is the most used polymer processing technique to make individual, complex products . An injeExtrusion and injection molding are the two main melt processing techniques used in industry. Many other processing techniques such as blow molding, cast extrusion, thermoforming, 3D-printing, and rotation molding are used in industry, but they are either derived from extrusion processes, or less widespread in industry and therefore considered to be out of scope for this review article.A large variety of processing parameters can be changed to control and optimize the extrusion and injection molding process. Nevertheless, these can be reduced to four fundamental parameters: (1) moisture content in the polymer, (2) processing temperature, (3) residence time, and (4) shear. For example, the screw rotation speed will affect both the residence time and the shear of the melt during extrusion. Also, large shear (due to the die geometry or high compression ratio of the screw) will create shear heating, which affects the processing temperature. Altogether, these four fundamental parameters determine the amount of process-induced degradation of the polymer.Hydrolytic degradation is the cleavage of ester linkages in the polymer backbone when PLA is exposed to moisture, resulting in carboxyl and hydroxyl linear polymers or oligomers with shorter chain length . The splThermal degradation occurs when PLA is exposed to high temperatures, becoming effective above 100 °C through the scission of the ester bonds . A complDegradation of PLA describes any mechanism that results in shortening of the polymer chains and reduction in the molecular weight , caused Thermomechanical degradation occurs when PLA is exposed to high mechanical stresses due to elongational and shear flow during processing. Mechanical loading causes the breakage of the long polymer chains into shorter fragments, as well as shear heating ,47. BothDepending on the selected processing characteristics, one of the above-described mechanisms will dominate PLA degradation. This emphasizes the importance of a proper selection of processing methods and conditions, since they can influence the extent of the process-induced degradation and minimize the undesired decrease in molecular weight.As a result of the degradation reactions, changes in chemical structure, molecular weight distribution, and mechanical, thermal, rheological, and permeability properties may occur. In order to identify the effect of processing on the properties, both in-line and off-line measurements can be adopted. Off-line measurements are used to investigate the properties of the extrudates after PLA is processed, whereas in-line measurements can identify degradation while PLA is melt-processed. This section will provide an overview of different off- and in-line measurements that can be used to monitor the extent of PLA-degradation.To understand the effect of processing on the properties of the end-product, off-line measurements are crucial. Degradation of PLA can be quantified by investigating the molecular weight distribution and chemical structure after processing, and by studying the thermal, rheological, mechanical, and visual properties of the extrudates.The most obvious method to investigate process-induced degradation of PLA is studying the molecular weight distribution of virgin and processed PLA, since melt processing causes cleavage of the chains into shorter fractions. Gel permeation chromatography (GPC) is used to investigate the average number-molecular weight  with a parallel plate rheometer; (2) apparent viscosity (ηapp) with a capillary rheometer; and (3) intrinsic viscosity ([η]) linked to the viscous molar mass (Mv).Rheological properties of polymers are crucial during polymer processing and they are directly linked to the molecular weight of the material. Thereby, different researchers use the viscosity of a polymer to monitor the degradation by performing different measurements: (1) complex viscosity (η*) and zero-shear viscosity  . Benvenu0~Mw3.4)  reporteda et al.  investigr et al. , Botta er et al. , and Scar et al.  investigr et al. ,63,64 rer et al. , a decreapp of extruded PLA was concluded to be lower than the ηapp of neat PLA, also due to the decrease in molecular weight as a result of degradation processes. Although a capillary rheometer measures the viscosity at shear rates higher than 10 s−1 and makes it thereby impossible to measure η0, it can still be used to monitor process-induced degradation. It is important to emphasize that the thermomechanical loading during capillary rheometry is not identical to industrial processes such as extrusion or injection molding, since only conductive heating occurs and the melt is sheared shortly when it is being pushed through the capillary.A second method is to use capillary rheometry to monitor the degradation of PLA, as reported by Nekhamanurak et al.  and Peinv of 22% was reported after five reprocessing cycles of PLA. Other researchers ) and an increase in MFI. In addition, the discoloration and the change in functional groups studied with FTIR were concluded to be good indicators for degradation, although they are less often studied in literature on this topic. It is more complex to use thermal and mechanical properties to monitor the degradation, since the decrease in molecular weight enables easier crystallization and can thereby result in an increase in the degree of crystallinity. In addition, the degree of crystallinity is also influenced by the optical purity of the PLA that was used in the different studies. If and how strong melt processing will alter the thermal and mechanical properties is a complex balance between these three events affecting each other. This complexity emphasizes that it is crucial to be aware that the extent of the degradation, and thus the change in properties, is dependent on which PLA-grades and processing equipment were used and which processing variables were selected.It is important to understand which properties are altered as a result of melt processing and thus can serve as indicators to monitor the degradation of PLA. The molecular weight distribution and thereby also the rheological properties directly linked to the molecular weight, were concluded to be the best suited properties to measure and understand PLA degradation. A general trend was reported: processing PLA results in a decrease in Therefore, the third section of this review paper described the influence of different processing conditions on the process-induced degradation of PLA. As expected, a similar trend was found by different authors studying the processing temperature and moisture content: increasing the moisture content and processing temperature results in more degradation and thus a larger decrease in molecular weight. Chain scission reactions linked to hydrolytic and thermal degradation explain the importance of processing at a temperature below 200 °C and drying PLA prior to melt processing. The conclusions about all other investigated processing conditions  are often contradictory. Some authors concluded that increasing the screw rotation speed caused less degradation, whereas others reported more degradation. This stresses the importance of expressing the degradation in terms of the four independent fundamental parameters that directly govern the extent of degradation  instead of other processing variables. Multiple processing variables contribute to the total shear on the material, such as the screw rotation speed and the screw configuration that may contain kneading and mixing elements. On the one hand, increasing the screw rotation means that the shear stresses will be higher and additional heating will occur due to shearing of the material, resulting in more thermomechanical and thermal degradation. On the other hand, increasing the screw rotation speed reduces the residence time and thus reduces the time that the melt is exposed to high temperatures and shear, which will reduce the amount of degradation. Also, shear heating results in a decrease in viscosity and thus less shear stresses on the melt. How the different processing conditions will affect the degradation of PLA depends on the balance between the four fundamental parameters. Overall, it can be concluded that high shear stresses should be avoided and that the residence time should be as short as possible, but it is important to realize the difficulty of translating this to ideal processing conditions since these are dependent on the equipment used in the experiments of the current literature.In the last part of this review paper, different methods were presented to enhance melt stabilization of PLA. Chain extenders and branching agents reconnect cleaved chains and thereby increase the molecular weight, resulting in an improvement of the thermal stability. Antioxidants act by neutralizing radicals and stabilize the degradation rate and molecular weight. Thermal stability is also obtained by adding (in)organic fillers to the melt, which also enhances the crystallization rate.Comparing results from different studies is difficult, since results are equipment-dependent. The size of the extrusion screw (L/D ratio), the screw geometry (length and depth of different zones), and the screw configuration (use of kneading and mixing elements) have a large effect on the shear loading and residence time of the material inside the extruder. Also, additional shear heating and thus thermal loading on the material should be considered. In the future, it would be meaningful to express total degradation in terms of the four fundamental parameters instead of equipment specific processing variables. This means that the combination of processing variables should be translated towards a total sum of the shear stresses, the final residence time of the melt inside the equipment, the final temperature of the melt (which will be slightly higher than the selected processing temperature due to shear heating), and the moisture content of PLA during processing. By translating all processing variables to fundamental variables, it will be possible to compare the results of multiple studies that used different settings and equipment.Not all authors take into account interaction effects between processing variables. The work of Mysiukiewicz et al.  concludeCompanies and researchers who are new to working with PLA, are often aware of the degradation occurring during melt processing, but do not know how to properly select the processing conditions that minimize the molecular weight decrease. The same difficulty arises when a new PLA-grades are selected and processed. The general trends on how the processing conditions affect degradation are understood in the literature, but the advice of different researchers on the correct set of processing conditions are not applicable since other processing equipment with a different geometry is used. In future work, it will be interesting to set up a quantitative degradation model that is able to predict how large the molecular weight decrease will be and that is generally applicable for different types of equipment. This requires the model to be based on the four fundamental parameters determining the degradation. If a polymer processing company wants to process PLA in the future, it can then input the desired set of processing conditions in the model, which then calculates the expected decrease in molecular weight. By varying the input parameters in the model, the effects of variables can then be estimated and the desired processing conditions can be tuned to deliver the lowest extent of degradation possible. It can help companies to overcome an expensive trial and error phase in production, since it can save time to find the optimal settings and can reduce the amount of industrial PLA waste.The degradation of PLA is investigated thoroughly, since the degradation reactions and kinetics are known in depth, and it is considered a significant challenge. Researchers and industrial processors are aware that PLA is sensitive to degradation, meaning that they have to pay attention during melt processing to select the processing conditions carefully. Although the general trends on how processing affects degradation are discussed in the current literature on this topic, multiple pathways are identified that may be of interest in future work:This literature review paper gives an overview on the available studies that discuss different properties that can be used to monitor process-induced degradation of PLA and the effects of different processing variables on the extent of the degradation. The fundamental knowledge about PLAs sensitivity to degradation is understood well in the current literature and is widely recognized as an issue during polymer processing, although some interesting pathways have been defined for future work. The usage of PLA and other biobased polyesters is expected to increase over the coming years in a large variety of applications, due to more environmental awareness by both companies and customers. Further investigation of the effect of processing variables will be crucial to prevent deterioration of the PLA properties and to produce high quality products. Understanding and predicting the effects of processing variables on the degradation will become crucial to use the available resources in a responsible way and support the polymer industry in producing them in an effective way.