Abstract:
Presented in this paper is a 4-dof robomech consisting of a stack of two five-bar (5R) chains with multiple end effectors to perform two distinct yet coordinated tasks simultaneously. The over-constrained kinematics chain cannot traverse continuous trajectories but may be synthesized to move the end effectors through a set of desired locations. The article elaborates on the architecture of the proposed robomech, establishes its kinematics relations and constraints, and provides dimensional synthesis scheme based on genetic algorithm and gradient search methods. A case study featuring the robomech performing spot welding operation along two distinct trajectories is included to demonstrate the applicability of the proposed robomech. Copyright © 2006 by ASME.