Torque Minimized Design of a Light Weight 3 DoF Planar Manipulator

The main objective of this paper is to design a robotic arm with all the motors located at the base so that the arm becomes lighter than the conventional arms where each motor is set on the links themselves which will lead to an extra weight of the motor to be held by previous motors. The main advantage of this development is to decrease the torque required to control the arm. The motion of motors transferred to links via aluminum pulleys, bearings, and timing belts that yield to the need of lighter motors and hence a lighter manipulator. The maximum torque of each joint has been calculated then compared with the torque required using conventional structures. The proposed arm has been built and tested. The simulation and experimental results reveal a noticeable improvement in the required maximum torque, which was reduced to less than half in some links.