一种苹果采摘机器人关节伺服控制系统设计及仿真

Design and simulation of a joint servo control system for an apple-picking robot

摘要:

当前，苹果采摘机器人大多都选用工业机械臂，关节控制都采用电机加减速装置来提高控制精度、增大驱动力矩，这无疑会增加系统的复杂性、成本以及降低系统控制性能。为改善这种情况，给出一种基于直流力矩电动机加谐波减速器的苹果采摘机器人关节控制方案，系统可大大减小驱动机构体积，提高系统刚性，实现低速稳定的精准控制。MATLAB环境下仿真结果表明, 在0.5°和60°的阶跃给定下，系统超调量和稳态误差均为0；在幅值为5°，频率为3.14rad/s正弦信号输入下，系统输出能够完全跟随输入。系统控制精度达到了苹果采摘要求，为后续简化采摘机器人机械臂结构、甚至实现直接驱动提供了有力的理论支持。

Abstract:

At present, most apple-picking robots use industrial mechanical arms. Motor and reduction gears are generally used in the joint control for apple-picking robots to improve the control accuracy and increase the driving torque. It will undoubtedly increase the complexity and reduce the control performance to the system. In order to improve this situation, a joint control scheme of apple-picking robot based on DC torque motor and harmonic reducer is proposed . The system can greatly reduce the volume of driving mechanism, improve the system rigidity, achieve precise control of low speed and stability. The MATLAB simulation results show that the system overshoot and steady state error were all zero under the step inputs of 0.5°and 60°, the system output could completely follow the input by taking sinusoidal signal with 5°amplitude and 3.14rad/s frequency as system input. The control precision of the system reached the requirement of apple picking. It’s able to provides a strong theoretical support for simplifying the mechanical arm structure and even realizing direct drive for apple-picking robot.