柔性机械臂的动力学模型及滑模变结构控制

DYNAMIC MODELING AND VARIABLE STRUCTURE CONTROL OF A FLEXIBLE BEAM

本文针对轴向不伸长的Euler-Bernouli梁模型,采用假设模态法,对带有末端荷载的柔性机械臂,推导出考虑动力刚化影响的柔性机械臂有限维一致线性化动力模型.通过极点配置技术设计滑模超曲面参数,采用滑模变结构控制方法,实现关节转角的运动轨迹控制.采用LQR方法设计弹性模态稳态器,抑制由于刚体运动而激发的弹性振动.文中最后针对一单杆柔性机械臂进行了计算机仿真,验证了本文所提出的控制策略的有效性.

In the paper, a consistent linear dynamic model in finite dimensions of a horizontally slewing inextensible Euler-Bernouli beam, taking into account the Dynamic Stiffening effectand a tip payload, is derived by using mode assumption method. A pole assignment technique is used to design the coefficients of the sliding surface. A Variable Structure Control (VSC) method is applied to achieve the joint angle trajectory tracking. To suppress the simultaneous elastic vibrations in movement, a stabilization device for elactic modes is designed by using the LQR control method. Numerical simulation results for a single-link flexible beam are presented to show the effectiveness of the proposed control strategy.