Research And Development On Open Architecture Control System Of Industry Robot

Control system is the brain of industrial robots, which is responsible for driving mechanical body of robots according to the user instructions. Thus, control system has the greatest significant influence on the performance of industrial robots. Traditional robot control systems are based on closed architecture, which is error-prone, providing poor extensibility, portability and network function.To solve the problem stated above, the dissertation carries out thorough researches on the theories of robot kinematics and trajectory planning under the goal of developing a kind of robot control system based on open architecture. In this dissertation, a hardware platform composed of “PC + Motion control card” is employed, and several key control software modules are developed using MFC. In this way, an open robot control system is implemented. The main works of this dissertation include:Firstly, the SCARA industrial robot is studied. The kinematics model is formulated using D-H method, followed by corresponding forward and inverse kinematic analysis. For the purpose of enhancing absolute positioning precision, several kinematic calibration algorithms are explored, and the error model for SCARA industrial robot based on distance error is formulated.Secondly, trajectory planning of the robots is explored thoroughly. In detail, linear planning with parabolic transition is utilized to achieve a continuous and smooth trajectory of displacement and velocity for in the joint space. Besides, trajectories in Cartesian space are transformed to that in joint space where control of robot is conducted. Given the problems of switching frequency and overshooting caused by common velocity control strategies of linear blocks, the dissertation proposes a kind of axis-number-independent velocity look ahead algorithm. Simulation results of the algorithm prove its effectiveness.Thirdly, modular design principle is applied in the development of overall architecture of the whole system under the requirements of open robot control system. Following functionalities are implemented: parameters setting, manual control, auto running, simulation, states monitoring and so on. Furthermore, the G Code compiler, graphic programming tool based on DXF files as well as OpenGL-based simulator are realized.Finally, experiments are performed to validate the functions and performance of the proposed control system. Experimental results show that the proposed controller can achieve desired openness and performance as well as excellent maintainability, meeting the requirements of the kind of open robot control system.