This paper presents the validation of a marker-less motion capture system used to evaluate the upper limb stress of subjects using exoskeletons for locomotion. The system fuses the human skeletonization provided by commercial 3D cameras with forces exchanged by the user to the ground through upper limbs utilizing instrumented crutches. The aim is to provide a low cost, accurate, and reliable technology useful to provide the trainer a quantitative evaluation of the impact of assisted gait on the subject without the need to use an instrumented gait lab. The reaction forces at the upper limbs’ joints are measured to provide a validation focused on clinically relevant quantities for this application. The system was used simultaneously with a reference motion capture system inside a clinical gait analysis lab. An expert user performed 20 walking tests using instrumented crutches and force platforms inside the observed volume. The mechanical model was applied to data from the system and the reference motion capture, and numerical simulations were performed to assess the internal joint reaction of the subject’s upper limbs. A comparison between the two results shows a root mean square error of less than 2% of the subject’s body weight.

中文翻译：

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用于评估外骨骼用户上关节反作用力的无标记系统的验证。

本文介绍了无标记运动捕捉系统的验证，该系统用于评估使用外骨骼进行运动的受试者的上肢压力。该系统将商用 3D 相机提供的人体骨骼与用户利用仪器拐杖通过上肢与地面交换的力相融合。目的是提供一种低成本、准确且可靠的技术，可帮助训练者定量评估辅助步态对受试者的影响，而无需使用仪器化步态实验室。测量上肢关节处的反作用力，以提供针对该应用的临床相关量的验证。该系统与临床步态分析实验室内的参考动作捕捉系统同时使用。一位专家用户使用仪器拐杖和受观察体积内的力平台进行了 20 次步行测试。将机械模型应用于来自系统和参考动作捕捉的数据，并进行数值模拟以评估受试者上肢的内部关节反应。两个结果之间的比较显示，均方根误差小于受试者体重的 2%。