Paper:

# Synthesis and Prototyping of a 6-dof Parallel Robot for the Automatic Performance of Assembly Tasks

## Jérôme Landuré^{*}, Clément Gosselin^{*}, Thierry Laliberté^{*}, and Muhammad E. Abdallah^{**}

^{*}Laboratoire de Robotique, Department of Mechanical Engineering, Université Laval

1065 Avenue de la médecine, Québec, Qc G1V0A6, Canada

^{**}Manufacturing Systems Research Lab., General Motors Research and Development

GM Technical Center, Warren, MI 48092, USA

This paper presents the development of a 6-dof parallel robot for the performance of assembly tasks in a human-robot collaborative environment. The architecture and design of the robot are selected such that the robot is mechanically backdrivable. Thereby, the robot can physically interact with an environment or with humans without requiring the use of a force/torque sensor, which is the main objective of this work. The architecture of the robot is first described and its kinematic model is established. The Jacobian matrices are derived and an algorithm is presented for the determination of its workspace. The force capabilities of the robot are then established based on a proposed formulation. A prototype of the robot is presented and control schemes are developed, including a controller based on a vision system. Finally, a video demonstrating the experimental validation of the robot accompanies this paper. The video qualitatively demonstrates the interaction capabilities of the robot.

*J. Adv. Comput. Intell. Intell. Inform.*, Vol.26 No.2, pp. 125-137, 2022.

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