Design of Articulated Manipulators Based on Kinematic and Dynamic Criteria

Abstract

Abstract This paper deals with the design of articulated manipulators with joint motion constraints. The aim is to design smaller and lighter robots by taking into account kinematic and dynamic criteria and the application. Painting and welding of large areas are the applications considered for which the end effector carrying the necessary tool should move at a uniform velocity in the work area. Further entire work area and the area required for acceleration and deceleration, must also lie inside the workspace of the manipulator. From kinematic consideration, link dimensions, joint rotation ranges and mean positions are obtained such that the required work area lies inside the workspace. The cross-sectional dimensions of the links are chosen such that the tip deflection under the worst loading conditions is less than a given minimum. The worst loading is obtained by considering the static loads due to weights of payloads, links, actuators and transmission elements and the dynamic loads due to the motion of the links. The torque requirements for a specified process velocity and acceleration depend on the loading and also on the kinematic parameters such as link lengths, joint ranges and mean positions. Hence the link dimensions, joint ranges and mean positions are optimized for minimum torque and the results are compared with those found from purely kinematic considerations.