Experimental Study of the Methodology for the Modelling and Simulation of Mobile Manipulators

Abstract

This paper describes an experimental study of a novel methodology for the positioning of a multi-articulated wheeled mobile manipulator with 12 degrees of freedom used for handling tasks with explosive devices. The approach is based on an extension of a homogenous transformation graph (HTG), which is adapted to be used in the kinematic modelling of manipulators as well as mobile manipulators. The positioning of a mobile manipulator is desirable when: ( 1 ) the manipulation task requires the orientation of the whole system towards the objective; ( 2 ) the tracking trajectories are performed upon approaching the explosive device's location on the horizontal and inclined planes; ( 3 ) the application requires the manipulation of the explosive device; ( 4 ) the system requires the extension of its vertical scope; and ( 5 ) the system is required to climb stairs using its front arms. All of the aforementioned desirable features are analysed using the HTG, which establishes the appropriate transformations and interaction parameters of the coupled system. The methodology is tested with simulations and real experiments of the system where the error RMS average of the positioning task is 7. 91 mm, which is an acceptable parameter for performance of the mobile manipulator.