Design, Modeling, and Control of a Low-Cost 4-DOF Robotic Arm: Experimental Evaluation of Pick-and-Place Tasks

Abstract

This investigation describes the development of a low-cost 4-DOF robotic arm based on education and competition in robotics. The arm is powered by SG90 servo motors and the control is guided by a joystick interface attached to an Arduino Uno microcontroller. The mechanical system was made from lightweight acrylic for efficient assembly and rigidity enough for basic motion. Experimental tests included assessment of movement accuracy, object grasping as well as system stability with various operating conditions. The robot achieved pick-and-place behaviour for lightweight objects and could perform the job successfully, with an accuracy acceptable under entry-level mechatronics design. Yet, with various weaknesses experienced, including motor vibrations, insufficient lifting capability and code timing sensitivity. Nevertheless, the prototype can be considered as an effective framework for the study of the kinematics, servo control, the human and machine interaction. The findings show that the inexpensive educational robot arms can play a pragmatic role in training, experimentation and learning automation. Download full text