A Parameter Identification Method for Coupled Dynamics of Robotic Manipulator with Differential Modular Joints

In the daily nursing care for people with disabilities, lifting is the most basic and common action. A robotic manipulator with differential modular joints (DMJ) is designed to accomplish this task. To better implement force-control applications of the robotic manipulator with DMJs, this paper proposes a coupled dynamics identification method based on the multi-input, multi-output (MIMO) feature. Considering the frictions of transmission parts and links, the dynamics of the DMJ is analyzed based on the transformation of energy, and then the parameter-linearized dynamic model of the robotic manipulator with n DMJs is proposed according to the mapping relationship between transmission part level and link level. The identification and verification experiments show that the presented method can obtain the accurate dynamic model parameters. This work lays a foundation for the force-control research of the robotic manipulator with DMJs in the future.