Tactile-sensing apparatus for sensible catching of guided heavy masses

This paper presents the development of an apparatus for sensitive catching of guided, heavy masses (10...13 kg). The apparatus uses a spring-supported tactile sensor to measure contacts, respectively forces, and two magnetic grippers for catching and holding the drop-weight. The tactile-sensor stamp allows a dexterous catching of the drop-weight by slightly moving the gripper away to reduce harsh physical impacts. This research is based on a project to automate the calibration process for the so-called light drop-weight tester. Such drop tests are currently executed manually, as they require a high degree of dexterity. However, this work is unergonomic, with high repetitions of a load. Additionally, the operator has to perform all tests with a high degree of sensitivity, since the measuring results are adversely affected by impacts and the resulting mechanical vibrations. The single axis catching apparatus developed by the Fraunhofer IFF solves the catching problem sole ly through use of tactile information (e.g. a vision system is not required). The developed solutions could be modified for a similar apparatus with multiple degrees of freedom.