Mechanical and Geometric Constraints for Robotic Assembly with a Single Manipulator

This study investigated an assembly strategy that leverages only a single robotic manipulator and an attached parallel gripper. This approach reduces the need for additional fixtures, such as manipulators and fixturing jigs, and minimizes costs and workspace footprint. We discuss the mechanical and geometric conditions required to improve the robustness of objects in the assembly process. The mechanical conditions represent the force equilibrium of multiple objects, and the geometric conditions restrict the movability of the objects. As some of the support jigs used in the experiments were not controlled to firmly fix the assembled objects, the above conditions were essential to guarantee the robustness of the temporarily assembled parts. This paper presents a successful case of automated assembly using a single manipulator, demonstrating the potential of the proposed method.