Development of a Novel HyRoHILS System and Its Application to Parameter Identification of an Industrial Robot

For the development of control algorithms and functions of industrial robots, test and verification with real robot system is an essential stage, and always requires not-ignorable and time-consuming implementation process. Implementing control algorithms directly on the ready-to-sell robot system from the beginning is never productive work, because the commercial robot control system has too many restrictions to be used as a design and test platform. Especially the shortage of calculation capability, memories and I/O devices and the complexity of the software structure are major barriers of direct coding on it. Previously, we had developed the HyRoHILS (Hyundai Robot Hardware In the Loop Simulation) system, as a rapid control prototyping platform for the fast development of industrial robot control algorithms. This system drastically reduced the development lead-time through automatic code generation of control algorithms on the RCP(Rapid Control Prototyping) device and also through provision of the powerful test automation and real-time monitoring environment. It provided us with powerful computing capability and convenient development environments, so it enabled us to concentrate on control algorithm design and test without concerning on any other annoying stuffs related to implementation. However, the software and hardware of the previous HyRoHILS system such as trajectory planner, motor driver were different from those of real commercial robot controller. It may cause that the experimental results of the HyRoHILS system are somewhat different from those of the real robot control system. Thus for developing a reliable robot control algorithm, additional verification test with real robot controller is required. In this paper, the novel HyRoHILS system is introduced. It is composed of a host PC, a commercial robot controller including the internal DSP board, and the RCP device. To the RCP device, control algorithms and functions to be tested are downloaded from the host PC. The RCP device shares the memory with the internal DSP board of the robot controller through DPM(dual port memory). It enables the RCP device to receive the position information from the encoders of a robot manipulator and also send the control signals generated by designed control algorithms and functions to the motor drivers of the robot controller in real time. In other words, all software and hardware of the novel HyRoHILS system are identical to those of the commercial robot controller except control algorithms and functions. As a result, we can evaluate only the effect of control algorithms and functions with more reliable experimental results through the novel HyRoHILS system. Finally, as an example to use the novel HyRoHILS system, the application to identify the parameters of a multi-axis industrial robot is presented. Identification of parameters (e.g. the motor and load inertia, stiffness, damping and so on) is time-consuming work with the commercial robot control system, but it can be easily accomplished with this novel HyRoHILS system. The results show the usefulness of the novel HyRoHILS system as a control design and test platform of the industrial robot. We believe that the novel HyRoHILS system is a better solution to a rapid control prototyping platform of the industrial robot than the previous one.