五杆四驱动平面双足机器人动态步态规划与非线性控制

Gait Planning and Nonlinear Control of Dynamic Walking for a Five-Link,Four-Actuator,Planar Biped Robot

以五杆四驱动的平面双足步行机器人为对象,研究了其动态步行的时不变步态规划和限定时间的非线性控制策略.揭示了其模型的欠驱动和完全驱动的混杂和非光滑动力学特性,推导了其碰撞模型.基于虚拟约束的概念,提出时不变步态的输出函数解析设计方法,设计了反馈线性化控制器,将系统转化为双积分环节.然后采用限定时间控制器在一步内零化输出函数.仿真实验表明,动态步行趋于一个稳定的极限环,实现了规划的行走模式,验证了该方法的有效性.

This paper addresses time-invariant gait planning and finite-time nonlinear control strategy for a five-link, fouractuator planar biped robot to realize dynamic walking. Nonsmcoth character and hybrid models, composed of under-actuated phase and fully-actuated phase, are uncovered, and the collision model is derived. Based on the concept of virtual constraint, we present a method to design output functions analytically for time-invatiant gait, and design a feedback linearization controller which transforms the system into a loop of double integrator. Then, the outputs can be stabilized to zero within a step by a finite-time controller. Simulation results indicate that a stable limit cycle of dynamic walking is achieved, the planned walking pattern is realized, and the effectiveness of the proposed method is verified.