The study of control methods for the robotic testing system for human musculoskeletal joints

Biomechanical testing of human musculoskeletal joints not only requires qualified testing machines and devices, but also needs an excellent control method to obtain better experimental results. In this paper, we take the human functional spinal unit (FSU) as an example to study how to improve the performance of the robotic testing system. First, the mechanical characteristics of the FSU are described and the simplified model (a rigid body-spring system) for the specimen is given. Because the location of the center of rotation (COR) of the specimen affects the performance of the system, so a comprehensive analysis on the location of the COR is carried out. Furthermore, the performance of the robotic testing system can be also improved through the improvement of the control methods. Two control methods have been proposed, one is the improved hybrid control and the other is fuzzy logic control (FLC).