Series-parallel 6-DOF Robot Dynamics And Control Research

At present, the research on the 6-DOF parallel robot has become a hot area. However, the vast majority of 6-DOF parallel robot configurations are derived from the Stewart institution, rare in other configurations of parallel robots, or series-parallel robots. In this paper, the study of 6-DOF series-parallel robot is mainly used in heavy-duty forgings automated production area. This body not only has the characteristics of high precise output, institutional rigidity, strong load capacity, but also has capability of a large working space.In this paper, the key research on 6-DOF series-parallel robot included five topics: kinematics analysis, dynamics analysis, control system design based on the dynamics, electro-hydraulic control system design and electro- hydraulic positon serve control.Kinematics analysis of the 6-DOF Series-Parallel robot has advantages and difficulties of both parallel robots and serial robots, a new approach is used to solve inverse positon in this paper, that is successive search method. Velocity and acceleration are analysised with frist and second-order effect coefficient matrix. At last, each joint trajectory is planed in joint space.Kinetic equation was derived based on KANE dynamics theory, and the basic equations of the kinetic coefficients were analyzed. Meanwhile, the robot dynamic state was simulated with Matlab software. Simulation curve was analyzed, dynamic performance was evaluated, and the joint trajectory was updated.The various control ways have characteristic in controlling the precision, speed and stability of their own characteristics, control costs and achieve the degree of difficulty vary based on kinetic equation. Three methods that are computed torque method, robust control and variable structure sliding mode control were used in the precise control of the series-parallel 6-DOF robot. These methods were compared with the Simulink simulation example in application conditions.Dynamic model of electro-hydraulic servo drive sysrem is derivated, which including electromafnetic servo valve, Single-stage electro-hydraulic servo valve, vavle-controlled hydraulic cylinders power sector and load model.Third-order single-input, single-output mathematical model was derived. Electro-hydraulic servo position control system is conreolled through PID and variable structure robust adaptive control system, and this system has good speed and robustness.The performance curve was described supported by Matlab / Similunk numerical simulation and the pure mathematical reasoning.