Force Reflecting Hand Controller Design For Bilateral Teleoperation

Hand controller is a key part in the realization of bilateral teleoperation technique. As a human-machine interface, its performance affects the efficiency of bilateral teleoperation system directly. A generalized hand controller with 6 degree-of-freedom(DOF) is designed. Simultaneously, the issues of hand controller design, including the design indexes, mechanism, measuring and driving modules, together with control algorithm, are studied. After reviewing the design indexes in previous design of hand controllers, this paper proposes several key indexes suitable for a universal hand controller. With these indexes as principles, the functional modules of the hand controller are discussed.1. Design of a 6-DOF hand controller mechanism. The platform which is designed based on a Delta parallel mechanism with 3 translational DOF has satisfying workspace and proper rigidity. And the platform with 3 rotational DOF is designed with sufficient consideration of the comfort of handling and the complexity of control method. The mechanisms are both designed and assembled using the SolidWorks software. Based on the components provided by SolidWorks, the engineering print of the mechanisms are drawn, and the machine which fit the design demands are built.2. Kinematic analysis and static force analysis. In this thesis, the forward and reverse solution of position analysis is presented, and a simulation graph of the hand controller's workspace is got in Matlab environment. The graph embodying the velocity feature and static force feature is drawn after achieving the velocity Jacobian matrix and the force Jacobian matrix. It is confirmed that the hand controller fit position control in the case of large displacement. The parameters for driver selection and sensor selection are figured out using Jacobian matrix.3. Design and realization of control system. Measuring and driving modules are developed using serve motor and force/torque sensor, embodying the principle of light weight, simple control of hand controller and easy selection. Following the idea of zero-force control, a force controller is designed on a industrial personal computer. A virtual manipulator with 3 translational DOF, serving as slave hand, is developed using SimMechanics, which is a toolbox of MATLAB. Applying the bilateral PD algorithm, a bilateral control system is then accomplished. With a delay of 3 second being imposed on the bilateral control system, experimental results of bilateral teleoperation show that manipulate of the hand controller is direct and effective.