Implementation of 2-dof inverted pendulum control system robust against actuator uncertainties

초록

In this paper, we propose an implementation method for a 2-DOF pendulum control system that is robust against actuator uncertainties. In order to guarantee the robustness against the uncertainty of the actuator, we derive a model in which the robot body’s acceleration is the system’s control input. We then verify its validity by implementing a 2-DOF pendulum system using an omni-directional robot(ODR). The 2-DOF pendulum system can be stabilized without a mathematical model of the actuator in the proposed method. Therefore, it is possible to eliminate uncertainty in the actuator parameters. Furthermore, the method provides the advantages of flexible selection of motors used as actuators. First, we design a mechanical part to measure the angular velocity of the motor and to measure the inclination of an inverted pendulum. Second, we derive a mathematical model of a 2-DOF pendulum system for acceleration which the control input. The controller adopts the Linear Quadratic Regulator(LQR) to obtain the acceleration required for stabilization. The determined acceleration is converted to the velocity references of wheels through integration and transformation. The velocity references are followed through PI-velocity controllers. Third, the control system is implemented using the open source hardware Nucleo-32 F303K8 board. We illustrate the proposed control system’s effectiveness through stabilization experiments. Copyright© ICROS 2018.

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