A suggested simple design and inverse kinematics for a multi-degrees-of-freedom robot arm

Abstract

In this paper, architecture for the robot arm and a mathematical model was suggested to simplify the inverse kinematics that describes the movement and orientation of this end-effector. Although this design contains eight degrees of freedom, all the angular displacements and velocities could be formulated as functions of the three coordinates of the end-effecter starting point. These three values are enough to set the end-effector at the desired point in the workspace, and with the desired orientation. The tip of the end-effecter could be equipped with a grabber or any attached manufacturing tool. To check the reliability of the introduced mathematical model, a simple model for the arm was built using aluminum beams. The joints are actuated by stepper motors that are controlled by a microprocessor. The model executed the positioning and orientation of the end-effector with an accuracy of about 93% of any traveled distance. This lack of accuracy may be accounted for by the low resolutions of the used motors. In this study, the positioning and orientation were only considered, and future work is required for the analysis of loads and power capacities