The assembly challenge of the World Robot Challenge (WRC) 2020, which was a part of the World Robot Summit (WRS) 2020, aimed to complete rapidly changing tasks in high mix/low volume production through building agile and lean production systems that can respond to one-off products. The authors of this paper participated in the challenge with the team PneuBot from the Industrial Robotics Facility of the Italian Institute of Technology by developing a flexible assembly system. The purpose of this work was to develop an assembly system able to handle variations of parts and tasks with a minimal changeover in hardware and software. In particular, assembly tasks were carried out, such as the assembly of a DC motor, pulleys, and a flexible belt on a plate, starting from pieces of unknown positions and orientations on a tray. The proposed work cell is light-weighted and can be fast deployed and replicated. It is composed of two Universal Robots; an RGB-D camera mounted on the wrist of the robot, able to detect both the position and orientation of the different objects to manage; a custom gripping system composed of 3D printed fingers for manipulation purposes and miniature force sensors for the grasping detection.

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