Vision and Force Controlled Assembly

Automated assembly processes traditionally rely on a high level of accuracy in the feeding of parts and the robot positioning. The DLR lightweight robot provides a fundamentally new solution to the advanced part assembly in industrial manufacturing. All robot joints are equipped with not only motor position sensing but also with joint torque sensors, thus allowing position-, velocity- and torque-control. Compliant behavior can be arbitrarily defined, i.e., a relation between the position deviation and external force can be given for every section of the trajectory.

A combination of these compliance properties with an image processing system and an optimal assembly trajectory planning is used to solve an assembly task. The vision system identifies the objects and controls the robot motion to predefined relative poses, whereas the joint torque sensors provide local feedback about the parts in contact. Robustassembly trajectories are generated offline based on the geometry of the parts involved. The planning optimizes trajectories as well as compliance parameters in order to maximize the robustness of the insertion.


Andreas Stemmer
Institut für Robotik und Mechatronik
Deutsches Zentrum für Luft- und Raumfahrt e.V.
Oberpfaffenhofen, D-82234 Wessling
Tel: +49 8153 28-3821

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