Complexity of Heavy-Payload Forging Manipulator Based on Input/Output Velocity Relationship

Abstract

There are different definitions of complexity in many areas. For a heavy-payload manipulator, the kinematic coupling degree problem, which has much influence on its control and reliability, is very important. This paper proposes a definition of complexity to measure the kinematic coupling degree of a manipulator. After the manipulator's desired output motions in the workshop are obtained, the matrix relating the velocities of actuated joints to the velocities of all basic output motions is calculated. Based on the preceding matrix, the definition of complexity is presented. To illustrate the methods introduced in this paper, four types of heavy-payload forging manipulators (FMs) are analysed, and the type of FM with the smallest complexity is chosen as our prototype.