Approach for a smart device for active vibration suppression as an add-on for robot-based systems

다국어 초록 (Multilingual Abstract)

Robot-based systems are defined by the capabilities of links and joints that form the robot arm, the control including drive engines andthe endeffector. In particular, articulated robots have a serial structure. They have to carry the drive engine of each ongoing axis, whichresults in higher susceptibility to vibration. To compensate weak precision the German Aerospace Center (DLR) integrates a qualityimproving sensor system on the robot platform. A vibration monitoring system detects vibrations that affect the precision during motiontasks. Currently, higher precision is achieved by slowing down the speed in production. Therefore, a compromise is given between speedand precision. To push the limits for these two conflicting process properties, we propose an approach for an additional smart device todecouple the process-sensitive unit from disturbances arising through motion of the kinematic structure. The smart device enables activevibration suppression by use of a piezo-based actuator with a lever mechanism connected to a motion platform. The lever mechanismprovides the required force and displacement adaption. The platform provides mounting and steering of the process-sensitive components.

First, an insight into the automation task is given within this paper. Secondly, the system design is illustrated. Based on simulation resultsthe characteristic of the proposed mechanism is shown. Besides the mechanical properties like stiffness and lever amplification, dynamicalissues like the smallest eigenfrequency are discussed. To verify simulation results initial measurements are presented and discussed.

The paper sums up with the discussion of an implementation of a closed-loop control system to achieve vibration-free and fast motion.

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