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Force control for walking on soft terrains

Published online by Cambridge University Press:  09 March 2009

Hannu Lehtinen
Affiliation:
VTT Automation, P.O. Box 13022, FIN-02044 VTT (Finland)

Summary

Force control of walking machines is essential in a natural soft and uneven terrain. A load adaptive PI force control method for the hydraulic actuation system of MECANT I has been developed. The I term of the controller is changed according to the desired load. Force control satisfies the support requirement also when a leg penetrates the terrain. A method to distribute support forces in an optimal manner has been developed. A rule based altitude controller and a dead-zone and saturation based attitude controller calculates the desired body forces. Walking tests on uneven wet sand fields show the useful applicability of the method.

Type
Article
Copyright
Copyright © Cambridge University Press 1996

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References

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