基于动力学约束的动态运动基元机械臂轨迹规划

Trajectory planning in manipulator with dynamic movement primitives based on dynamic constraints

针对传统机械臂轨迹规划方法存在适用性差的问题,利用动态运动基元的学习与泛化特性规划出机械臂的运动轨迹。在动态运动基元的基础上,加入改进的耦合项来实现机械臂避障,再把对速度及加速度的约束转化为对时间缩放因子的约束,利用改进的更新律来满足机械臂动力学约束,从而提出一种基于动力学约束的动态运动基元避障轨迹规划方法,并通过仿真和物理实验验证该方法的可行性。结果表明,基于动力学约束的动态运动基元机械臂轨迹规划方法能够使机械臂在避障的同时,遵守速度或加速度约束,且速度约束可以在线修改;该方法可以提升机械臂在不同约束下的轨迹规划能力与环境适应性。

In view of the poor applicability of the traditional manipulator trajectory planning methods, the trajectory of the manipulator was planned by using the learning and generalization characteristics of dynamic movement primitives.On the basis of dynamic movement primitives, an improved coupling term was added to achieve obstacle avoidance of the manipulator.Then the constraints on velocity and acceleration were transformed into constraints on time scaling factor, and the improved updating law was used to meet the dynamic constraints of the manipulator. Thus, a trajectory planning method of obstacle avoidance with dynamic movement primitives based on dynamic constraints was proposed.The feasibility of the method was verified by simulation and physical experiments. The results show that the trajectory planning method of the manipulator with dynamic movement primitives based on dynamic constraints can make the manipulator obey the velocity or acceleration constraints while avoi-ding obstacles, and the velocity constraints can be modified online. This method can improve the tra-jectory planning ability and environmental adaptability of the manipulator under different constraints.