Backstepping Fuzzy Sliding Mode Controller for Trajectory Tracking of Mobile Manipulator
No Thumbnail Available
Date
2024-04
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
A Mobile Manipulator (MM) is essentially a robotic arm attached to a mobile platform, which
could be designed for space, ground, aerial, or underwater environments. The mobile platform
expands the reach of the manipulator, allowing it to access a larger workspace. This increased
mobility enhances the ability to position the manipulator in various configurations, leading to
more efficient task execution.
Mobile Manipulators has complex system structure, highly coupling dynamics between mobile
base and mounted manipulator arm, holonomic and nonholonomic kinematics constraints and
highly nonlinear characters substantially increase the difficulty in designing a controller for the
wheeled mobile manipulator.
Designing a robust controller for mobile manipulator with the aim of simultaneous control
of the velocity of the mobile platform and the motion of the end-effector is the aim of this
thesis work. By employing the concepts of kinematic backstepping control and fuzzy sliding
mode torque control, a two-step control approach is introduced for the nonholonomic mobile
manipulator. In the first step, the kinematic velocity control is designed to ensure that all desired
trajectories are achieved. In the second step, a fuzzy sliding mode torque controller, based
on the dynamics of the mobile manipulator, is designed to ensure that the mobile platform’s
velocity and the end-effector’s position converge to the reference trajectories generated in the
first step.
The proposed method stability is proved using Lyapunov theory, and its convergence is
mathematically guaranteed. Comparision between BSMC and the proposed BFSMC is conducted
in terms of tracking performance in the face of both disturbance and parameter variation
and the proposed BFSMC has shown better performance in tracking the given trajectory by
rejecting the external disturbances and tolerating the parametric uncertainties results in performance
improvement of 31.6%. The effectiveness of the suggested control approach is confirmed
through the creation of simulation outcomes using MATLAB/SIMULINK software.
Description
Keywords
Mobile Manipulator, Sliding Mode Control, Fuzzy Sliding Mode Control, Velocity Controller, Torque Control, Tracking Performance, External disturbance