Stability prediction of an UGV with manipulator on Uneven Terrain

Abstract

A mobile robot employed in Search & Rescue tasks has to carry a wide set of sensors to get the most possible information from the environment and at the same time has to traverse hard uneven terrain, facing difficult stability conditions that could lead the robot to tip over and compromise definitively the mission. In this paper a stability assessment approach is applied to a chained UGV with manipulator driving along a determined path on uneven terrain. The stability from the beginning to the end of the path is predicted using prior knowledge of the terrain. The center of gravity of the whole robot is calculated statically for a finite set of positions along the path. The direct kinematics of the manipulator is used to find the contribution of the manipulator’s masses to the overall center of gravity. The polygon described by the contact points between the robot and the ground plays a critical role to determine how close is the vehicle to tip over.