Lower Limb Prosthesis Movement Control Methol Based On Model-free Dynamic Matrix

With the development of sensor, intelligent control and rehabilitation engineering technology, the development of powered above-knee prosthesis has tended to intellectualization. Powered above-knee prosthesis, which not only can follow the movement of healthy limb, but also provide power support for the wearer in the stair ascent, stair descent, up and down slope, is different from the traditional prosthesis. The research and design of powered above-knee prosthesis has important theoretical significance and application value.The main topics of this thesis are information collection, processing and motion control of powered above-knee prosthesis. It realizes the real-time detection of prosthetic movement and coordination control with the healthy limb. And it improves the practicability and intelligence of the prosthetic products.Firstly, prosthetic movement decision procedure and artificial limb actuator delay will bring prosthetic movement delay, and result in the uncoordinated movement of both legs. In order to overcome this drawback, this thesis proposes to collect hip angle, acceleration and plantar pressure information of human motion movement with sensors, and correlation analysis information with template data, then fuse the correlation coefficient with D-S evidence theory to pre-recognize movement pattern. It can promptly formulate motion control scheme before driving the actuator, advance drive prosthetic knee joint and real-time adjust prosthetic gait to achieve the best control effect.Secondly, the movement of the human body is a complex process. And hip and knee joint motion modeling under different terrains is very difficult. Therefore, the thesis shows motion characteristics of five kinds of typical terrains through analysis information of lower limb motion. Then motion control strategy of prosthetic knee prosthesis movement. It makes prosthetic movement more natural to follow the healthy limb.Finally, considering the prosthetic actuator movement fast execution, short cycle, high repeatability, and high precision control requirements, this thesis selects the model-free dynamic matrix to control powered above-knee prosthesis. This control method just uses the changing information of the hip and knee joint angle. It not only completely avoids the problem which the control system is unable to establish the dynamic model, but also retains the existing rolling optimization and feedback correction strategy of the dynamic matrix control. It enhances the robustness of the system, improves the control accuracy.