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Vibratory Parts Feeding and Positioning - Sensorless Manipulation on a Vibratory Plate (1994-1997)

 

Team Members

Vivek Bhatt, Karl F. Böhringer, Bruce Donald (Cornell), Ken Goldberg (UC Berkeley)

 

Summary

The existing industrial parts feeders move the parts through a sequence of mechanical filters that reject parts in unwanted orientations. Here we develop a new setup that uses a different vibratory mechanism to systematically manipulate parts, by actively orienting and localizing them. The idea is to generate and change dynamic modes for a plate by varying the applied frequency of oscillation. Depending on the node shapes of the plate for these frequencies, the position and orientation of the parts can be controlled. We develop an analysis of the underlying dynamics, and show that it can be used to predict the behavior of objects placed on the vibrating plate. Using this analysis, we propose that the applied frequencies can be automatically sequenced to obtain a "sensorless" strategy for manipulating a given object.

Figure 1: Vibrating plate at frequency of 60 Hz. Experimental determination of nodal curve.

Figure 2: Part alignment at 60 Hz.

Figure 3: Vibrating plate at frequency of 20 Hz.

Figure 4: Part alignment at 20 Hz.

The existing industrial parts feeders move the parts through a sequence of mechanical filters that reject parts in unwanted orientations. In this paper we develop a new setup that uses a different vibratory mechanism to systematically manipulate parts, by actively orienting and localizing them. The idea is to generate and change dynamic modes for a plate by varying the applied frequency of oscillation. Depending on the node shapes of the plate for these frequencies, the position and orientation of the parts can be controlled. We develop an analysis of the underlying dynamics, and show that it can be used to predict the behavior of objects placed on the vibrating plate. Using this analysis, we propose that the applied frequencies can be automatically sequenced to obtain a "sensorless" strategy for manipulating a given object.

 

Selected Publications

A complete list of our publications (many of them available online) can be found here.

 

Acknowledgements