Adaptive network control of a mobile base with an onboard arm for MARS greenhouse operation

摘要

MARS greenhouse needs mobile robots with on-board arms, that are capable of navigating autonomously in the greenhouse, performing tasks such as carrying trays containing plants, farming, harvesting, house keeping, inspection, cleaning, health monitoring and so on. An adaptive network framework is introduced for the motion control of a mobilebase with an onboard arm using Lyapunov's approach and it is rigorously justified for MARS Greenhouse operation scenario wherein the tray weight containing plants change considerably. Initially, a linear in the parameter (LIP) based adaptive controller is designed to estimate the unknown parameters of the mobile base plus robot arm system after the incorporation of nonholonomic constraints. Later, the proposed adaptive network approach, which relaxes several key assumptions, is shown to be applicable with any function approximator. This adaptive network approach provides an inner loop that accounts for possible motion of the on-board arm, with changing endeffector loads, while the base is carrying out a task. The case of maintaining a desired course and speed as the on-board arm moves to its desired orientation with an unknown end effector load is considered.