Gesture imitation is a common rehabilitation strategy in limb rehabilitation training. In traditional rehabilitation training, patients need to complete training actions under the guidance of rehabilitation physicians. However, due to the limited resources of the hospital, it cannot meet the training and guidance needs of all patients. In this paper, we proposed a following control method based on Kinect and NAO robot for the gesture imitation task in rehabilitation training. The method realized the joint angles mapping from Kinect coordination to NAO robot coordination through inverse kinematics algorithm. Aiming at the deflection angle estimation problem of the elbow joint, a virtual space plane was constructed and realized the accurate estimation of deflection angle. Finally, a comparative experiment for deflection angle of the elbow joint angle was conducted. The experimental results showed that the root mean square error of the angle estimation value of this method in right elbow transverse deflection and vertical deflection directions was 2.734° and 2.159°, respectively. It demonstrates that the method can follow the human movement in real time and stably using the NAO robot to show the rehabilitation training program for patients.
动作模仿是康复训练中常见的训练策略。传统的康复训练中患者需要在康复医师的指导下完成训练动作，然而由于医院资源有限，无法满足所有患者的训练指导需求。本文针对康复训练中的动作模仿任务，提出了一种基于Kinect和NAO机器人的跟随控制方法。该方法通过逆运动学解析实现了Kinect坐标系到NAO机器人坐标系关节角度映射。针对肘关节偏转角的估计问题，通过构建虚拟空间平面实现了偏转角的精确估计。最后，基于肘关节的运动偏转角进行了对比实验，结果显示该方法右肘横轴偏转和纵轴偏转的角度估计值均方根误差分别为2.734°和2.159°，证实了该方法可以实现NAO机器人实时、稳定地跟随人体动作，从而向患者展示康复训练方案。.
Keywords: Follow control; Inverse kinematics; Kinect; Median filter; NAO.