Mobile manipulators have been employed in many applications that are traditionally performed by either multiple fixed-base robots or a large robotic system. This capability is enabled by the mobility of the mobile base. However, the mobile base also brings redundancy to the system, which makes mobile manipulator motion planning more challenging. In this paper, we tackle the mobile manipulator motion planning problem under the end-effector trajectory continuity constraint in which the end-effector is required to traverse a continuous task-space trajectory (time-parametrized path), such as in mobile printing or spraying applications. Our method decouples the problem into: (1) planning an optimal base trajectory subject to geometric task constraints, end-effector trajectory continuity constraint, collision avoidance, and base velocity constraint; which ensures that (2) a manipulator trajectory is computed subsequently based on the obtained base trajectory. To validate our method, we propose a discrete optimal base trajectory planning algorithm to solve several mobile printing tasks in hardware experiment and simulations.

翻译：移动机械臂已被广泛应用于许多传统上由多个固定基座机器人或大型机器人系统完成的任务中。这种能力源于移动底盘的机动性。然而，移动底盘同时也给系统带来了冗余性，使得移动机械臂的运动规划更具挑战性。本文研究了末端执行器轨迹连续性约束下的移动机械臂运动规划问题，其中要求末端执行器遍历连续的任务空间轨迹（时间参数化路径），例如移动打印或喷涂应用。我们的方法将问题解耦为：（1）在几何任务约束、末端轨迹连续性约束、碰撞避免和底盘速度约束下，规划最优底盘轨迹；这确保了（2）随后基于获得的底盘轨迹计算机械臂轨迹。为验证该方法，我们提出一种离散的最优底盘轨迹规划算法，并在硬件实验和仿真中求解了多项移动打印任务。