Design of a Low-Cost Mobile Robot With Manipulator

This study presents the design, development, and evaluation of a low-cost mobile manipulator system that integrates a differential-drive mobile base with a 4 -DOF robotic manipulator. Constructed entirely from off-the-shelf components, the system combines affordability with robust functionality, making it suitable for research, education, and lowcost industrial applications. The manipulator employs a 4-DOF RRRR configuration, powered by 12 V DC motors and equipped with a gripper capable of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{1 8 0}$</tex>-degree rotation. The mobile base features a differential-drive system that ensures precise navigation along predefined paths, supported by trajectory planning and kinematic modeling. Experimental investigations validated the ability of the system to execute coordinated navigation and manipulation tasks. The manipulator achieved a full range of motion in under 33 seconds, closely following desired joint angles with minimal error. The mobile base demonstrated accurate path-following capabilities, reconstructing global trajectories from encoder feedback. Despite the success, structural limitations due to the manipulator's weight and reliance on motor encoders for feedback highlight areas for improvement. This work contributes to the advancement of cost-effective robotic systems capable of addressing real-world challenges in dynamic environments.