Rubber Bearings for Precision Motion

MIT SEMINAR SERIES IN MANUFACTURING AND PRODUCTIVITY
Place: Room 35-225 Time: 12:00 P.M. Tuesday, February 28, 2006

Professor David Trumper

Professor of Mechanical Engineering

This presentation focuses on the use of thin rubber sheets as bearings in precision positioning systems. Such bearings have the potential to replace more conventional flexures fabricated for instance from metal. Rubber bearings also potentially have advantages in ease and low-cost of fabrication, overload robustness, and compact form.

To study the properties of these bearings we have designed a test fixture to measure the shear and compression characteristics of elastomeric bearings as a function of frequency, and of various design parameters. The bearing test fixture uses a voice coil actuator to apply either a compression or shear force to a rubber specimen, and uses a capacitance gage to measure the strain.

We have also designed and tested a rotary precision positioning system utilizing a rotary laminated rubber bearing. The bearing in this device consists of multiple laminates of metal and rubber sheet packaged within a preload mechanism, and driven by a commercial galvanometer.