Nonlinear rubber actuator design

2/01/2017 rev ADon Blanchet

3B Associates

dwb3298@verizon.net

Goals

Design a simple push pull actuator using basic mechanical components.

Low cost

Shape the force feedback (output)

Model proof of concept using nonlinear Finite Element Analysis

Concept

MoldedRubberblock

StainlessSteel pins3 places

Cross section

PinsMoldedIn place

Set gapFor

Force calibration

FEA mesh

InputDisplacement +X

direction

Output ForceFeedback

-X

Rubber Distortion(magnified)

Predicted calibration curve

CLOSE GAP

INITIAL LINEAR RUBBER RESPONSE

RUBBER HYPERELESTIC RESPONSE

Analysis method

Solidworks Simulation 2015

Nonlinear static analysis

– Nonlinear material properties using Mooney-Rivlin constants

– Buckling geometric nonlinearity

Solution is calculated 50 times at equally spaced steps

Torsional input mode

Conclusion

This actuator response actsapproximately as a digital state flip or a switch.

This design could be miniaturized.