This paper addresses the robot-assisted rehabilitation of back pain, an epidemic health problem affecting a large portion of the population. The design is composed of two springs in series connected to an end-effector via a pair of antagonistic cables. The spring and cable arrangement forms an elastic coupling from the actuator to the output shaft. An input-output torque model of the series-elastic mechanism is established and studied numerically. The study also illustrates the variation of the mechanism’s effective stiffness by changing the springs’ position. In addition, we built a prototype of the robotic mechanism and design experiments with a robotic manipulator to experimentally investigate its dynamic characteristics. The experimental results confirm the predicted elasticity between the input motion and the output torque at the end-effector. We also observe an agreement between the data generated by the torque model and data collected from the experiments. An experiment with a full-scale robot and a human subject is carried out to investigate the human-robot interaction and the mechanism behavior.

中文翻译：

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一种用于腰痛康复的串联弹性机器人

本文讨论了背痛的机器人辅助康复，背痛是一种影响很大一部分人口的流行性健康问题。该设计由通过一对拮抗电缆串联连接到末端执行器的两个弹簧组成。弹簧和电缆装置形成了从致动器到输出轴的弹性联轴器。建立并数值研究了串弹性机构的输入输出转矩模型。该研究还通过改变弹簧的位置说明了机构的有效刚度的变化。此外，我们建立了机器人机构的原型，并用机器人机械手设计实验，以实验研究其动态特性。实验结果证实了输入运动和末端执行器输出扭矩之间的预测弹性。我们还观察到扭矩模型生成的数据与实验收集的数据之间的一致性。进行了一个全尺寸机器人和人体实验，以研究人机交互和机制行为。