General-purpose Robot Joint Motion Controller Is Developed

Along with the development of robot-applying research and technology, the application of polyarticular robots or the mechanical arms is more and more extensive. The joint-motion controller is the core of robots controlling system. Precision and real-time become more and more important in applications. To design robots' joint-motion controller of new generation, it is required that the microprocessor, power electronics, advanced controlling theory, intelligence algorithm and so on.First of all, author presented the development survey of industrial robot, motion controller and motion control technique, analyzed the structure character of PMSM according to the PR robot, illustrated its mathematical models, studied the theory of vector control on PMSM further deeply, adopted Predictive Functional Control (PFC) to implement dynamic and frequent location control, and developed a kind of control scheme of the motion controller system.As for hardware, TMS320LF2407A is used as the core of the control unit. The power circuit makes the Active Power Factor Correction circuit (APFC) and intelligent power module (IPM) PS21564 for the AC-DC-AC voltage inverter. DSP generates six PWM signals to touch off the IGBT and drive the PMSM. According to the character of DSP and IPM, peripheral circuit, communication interface circuit, current collection circuit, velocity/position collection circuit, digit to analog circuit and protection circuit were designed. So a universal hardware platform for experiment of motion controller was finished.As for software, the control algorithm of PMSM was implemented by DSP program. It adopted the i_d=0 vector control method to realize the decoupling control of PMSM. The general digital PI control method was used in the current and speed loop, a kind of PFC-PID (Predictive Functional Control) control method was used in the position loop, and SVPWM modulation was used in the inverter. Furthermore, in order to satisfy the requirement of operation and communication, an operational panel and communication software were designed. In order to transplant and modify the programs conveniently, the frame of software based on μC/OS- II is also presented.At last, both hardware and software were debugged carefully, then several experiments were conducted and the results were analyzed accordingly. The results of experiments show that the design of the motion controller is reasonable, performance is reliable. It not only can be used to the PR robot in our lab, but also used to others AC motor, and has good application prospect.