ABSTRACT

Finding feasible solutions to motion planning and control problem of robotic systems in different environments with various applications is an active area of research. This article presents a new solution to the motion planning and control problem of a three-dimensional articulated mobile manipulator comprising a car-like mobile platform and a three-dimensional n-link articulated arm using the Lyapunov-based control scheme. The motion of the system is described as twofold: first, the car-like mobile platform moves from an initial position to its pseudo-target, and second, when the mobile platform is within some predefined distance from the pseudo-target, the end-effector of the robot arm is attracted to its designated target. Therefore, presenting a new 2-Step Algorithm in this paper for dual movement of the articulated mobile manipulator in 3D. In addition, a workspace cluttered with fixed spherical and rod obstacles of random sizes and positions is considered in this research. For the mobile manipulator to avoid an obstacle, the Minimum Distance Technique is adapted where a point on the robot that is closest to an obstacle will avoid the obstacle. The convergence of the two bodies and the stability of the mechanical system are guaranteed by the Lyapunov's direct method. The continuous nonlinear control laws proposed from the control scheme also take into account all mechanical singularities and velocity limitations associated with the system. Theoretical proofs and computer simulations validate the new continuous, acceleration-based, nonlinear, time-invariant control laws.

摘要

在具有各种应用的不同环境中为机器人系统的运动规划和控制问题寻找可行的解决方案是一个活跃的研究领域。本文提出了一种解决三维关节移动机械手运动规划和控制问题的新方法，该机器人包括一个类似汽车的移动平台和一个三维n- 使用基于 Lyapunov 的控制方案连接关节臂。系统的运动被描述为双重的：首先，类似汽车的移动平台从初始位置移动到其伪目标，其次，当移动平台距离伪目标一定距离内时，末端机器人手臂的效应器被吸引到指定的目标上。因此，本文提出了一种新的 2 步算法，用于 3D 关节式移动机械手的双重运动。此外，本研究考虑了一个杂乱无章的固定球形和随机大小和位置的杆状障碍物的工作空间。为了让移动机械手避开障碍物，最小距离技术适用于机器人上最接近障碍物的点将避开障碍物。李雅普诺夫直接法保证了两个物体的会聚和机械系统的稳定性。从控制方案提出的连续非线性控制律还考虑了与系统相关的所有机械奇异性和速度限制。理论证明和计算机模拟验证了新的连续的、基于加速度的、非线性的、时不变的控制定律。