Modelling fatigue in manual and robot-assisted work for operator 5.0

Occupational Applications: Fatigue, and many other human performance factors, impact worker wellbeing, and thus production quality and efficiency. Adopting the Industry 5.0 perspective, we propose that integrating human performance models into wider industrial system models can improve modeling accuracy and lead to superior outcomes. Integrating our Worker Fatigue Model as part of their industrial system architect model allowed Airbus, a leading aircraft manufacturer, to more accurately predict system performance as a function of the workforce makeup, which could be a combination of human workers and robots, or a combination of highly experienced and less experienced workers. Our approach demonstrates the importance and value of including human performance models in trade studies for introducing robots on the shop floor, and can be used to include various aspects of human performance in industrial system models to address specific task requirements or different levels of automation. Technical Abstract: Rationale: The advent of Industry 5.0 places a heightened focus on enhancing worker wellbeing during the digital transformation of factories. System models that ignore human workers yield suboptimal results in product design and system improvement.Purpose: In the aircraft industry, worker workload is of primary concern as most tasks are performed manually, leading to general fatigue and musculoskeletal disorders. Robot assistance could improve quality, efficiency and relieve workers from fatigue. To demonstrate the feasibility and value of integrating human performance models in system design at Airbus, a Worker Fatigue Model was developed, focusing on the effects of (1) automation (manual vs semi-automated), and (2) workforce makeup (various ratios of high-skilled to low-skilled workers). Our ultimate goal was to inform the development of effective policies and strategies for human-technology integration in Industry 5.0.Methods: We developed the Worker Fatigue Model by adapting existing fatigue models for workers in industrial environments and by considering worker characteristics, tasks, and the presence or absence of robot-assistance. Two different scenarios were simulated (fully manual and semi-automated), with input variables such as worker skill, age, and motivation, and output variables including overall fatigue and error probabilities were evaluated. The Worker Fatigue Model was integrated into the Airbus system model to conduct trade studies based on workforce characteristics.Results: Our findings revealed that the composition of the workforce (i.e., various ratios of high-skilled to low-skilled workers), alongside specific manufacturing technologies, significantly reduced worker fatigue, especially with higher ratios of high-skilled workers, and improved overall industrial system performance.Conclusions: Although applying our Worker Fatigue Model effectively demonstrated the feasibility and value of integrating human factors into early industrial system design, it remains a work in progress. Future work will aim to accurately represent the workload of human workers, including operational costs, when implementing robot assistance

Comparison of human trimanual performance between independent and dependent multiple-limb training modes

International audienceHuman movement augmentation with a third robotic hand can extend human capability allowing a single user to perform three-hand tasks that would typically require cooperation with other people. However, as trimanual control is not typical in everyday activities, it is still unknown how to train people to acquire this capability efficiently. We conducted an experimental study to evaluate two different trimanual training modes with 24 subjects. This investigated how the different modes impact the transfer of learning of the acquired trimanual capability to another task. Two groups of twelve subjects were each trained in virtual reality for five weeks using either independent or dependent trimanual task repetitions. The training was evaluated by comparing performance before and after training in a gamified trimanual task. The results show that both groups of subjects improved their trimanual capabilities after training. However, this improvement appeared independent of training scheme

How long does it take to learn trimanual coordination?

International audienceSupernumerary robotic limbs can act as intelligent prostheses or augment the motion of healthy people to achieve actions which are not possible with only two natural hands. However, as trimanual control is not typical in everyday activities, it is still unknown how different training could influence its acquisition. We conducted an experimental study to evaluate the impact of different forms of trimanual action on training. Two groups of twelve subjects were each trained in virtual reality for five weeks using either a three independent goals task or one dependent goal task. The success of their training was then evaluated by comparing their task performance and motion characteristics between sessions. The results show that subjects dramatically improved their trimanual task performance as a result of training. However, while they showed improved motion efficiency and reduced workload for tasks with multiple independent goals with practice, no such improvement was observed when they trained with the one coordinated goal task

Human Model For Industrial System And Product Design In Industry 5.0: A Case Study

International audienceHuman performance models can be included in industrial system models to improve the design of the industrialsystem, manufacturing processes, and product design. In our use case, a critical process in the production of a newairplane was being considered for automation. This process requires the highest quality assurance and is normallyperformed manually. Robot assistance could improve quality and efficiency. A human performance model focused onworker fatigue was developed, taking into account characteristics of the workers, robots, and tasks. Two differentautomation scenarios (fully manual, semi-automated), with different worker characteristics such as skill, age,motivation, etc. were studied. Using historical production line data in the fully manual scenario, and simulated datafor the semi-automated scenario, global fatigue scores and graphical visualization were generated by the model foreach scenario, allowing the system architects to understand the effects of the future production system on workers,including errors, time lost, costs and overall resilience of the system