液压驱动单元基于力的阻抗控制方法控制参数灵敏度分析

液压驱动型高性能足式仿生机器人具有很好的适应能力,为尽可能地避免其足地接触过程中的冲击和碰撞,足式机器人的关节应具有一定的柔顺性,而基于力的阻抗控制是一种在液压驱动型高性能足式仿生机器人腿部关节中常用的主动柔顺控制方法.针对驱动足式机器人关节运动的液压驱动单元(HDU),研究基于力的阻抗控制方法在HDU上的应用,推导其状态空间表达,并在HDU性能测试平台上对阻抗控制效果进行实验验证.针对影响阻抗控制效果的4个主要控制参数,对比分析不同灵敏度分析方法的优劣势,最终确定使用相对简单求解过程的一阶矩阵灵敏度分析方法,对4个参数在4种不同工况下进行动态灵敏度分析以及定量灵敏度分析,并进行实验验证.所得基于力的阻抗控制参数灵敏度分析结论可作为不同工况下控制参数优化的理论参考和实验基础.

Control parameters sensitivity analysis of force-based impedance control for hydraulic drive unit

The bionic legged robot, driven by hydraulic, has a better ability to operate in different working environment. In order to prevent the robotic foot end from impact and collision during its contact with the ground, it is necessary to design the robotic joint with certain dynamic compliance. Generally speaking, the force based impedance control is a commonly adopted method for active dynamic compliance control in the legged robot''s joints. Aiming at the joint driver of legged robot, which is called hydraulic drive unit (HDU), the application of the force-based impedance control method on the HDU is researched. The state space expressions are also developped. The control effect of the impedance control is tested experimentally on the HDU performance test platform. Then, aiming at the main four control parameters, the easier first order matrix sensitivity analysis method is selected according to the advantages and disadvantages of different sensitivity analysis methods. Particularly, the dynamic sensitivity analysis and quantitative sensitivity analysis are conducted for those four parameters under multiple working conditions. Finally, the test experiments are conducted. It is found that the experimental results obtained can be applied under different working conditions. Based on the control performance requirement, the values of control parameters can be compensated specifically and the control strategy can be well optimized.