LiU Electronic Press

Conference article

Dynamical Model of a Vehicle with Omni Wheels: Improved and Generalized Contact Tracking Algorithm

Ivan Kosenko
Department of Theoretical Mechanics, Moscow Aviation Institute, Russia

Sergey Stepanov
Department of Mechanics, Dorodnitsyn Computing Center of RAS, Russia

Kirill Gerasimov
Department of Theoretical Mechanics and Mechatronics, Lomonosov Moscow State University, Russia

Alexey Rachkov
Department of Theoretical Mechanics, Moscow Aviation Institute, Russia

Linköping Electronic Conference Proceedings 118:86, s. 803-809

Published: 2015-09-18

ISBN: 978-91-7685-955-1

ISSN: 1650-3686 (print), 1650-3740 (online)

Abstract

A model of the multibody dynamics for an omni wheel assuming embedded in a frame of wider dynamical environment of the whole vehicle is under development and verification. Modelica base classes developed earlier for the multibody applications with contacts involving friction are used. Generalization has been performed for the model of contact tracking algorithm between roller and horizontal floor. Generalization includes non-zero angle between the roller axis of rotation and plane of the omni wheel. Contact tracking algorithm is implemented in two cases: (a) implicit and (b) explicit.

Models for these cases (a) and (b) are currently “embedded” into the omni vehicle model earlier verified. For simplicity we analyze a multibody system comprising the wheel plus set of rollers being mounted along its circumference. A remainder of the vehicle is replaced by the wrench properly arranged in a way such that the wheel keeps its vertical orientation permanently. The performed computations have shown that two algorithms of the contact tracking generate completely identical dynamics of the whole multibody system.

Keywords

omni wheel; contact tracking; unilateral constraint; angled rollers; model of friction

References

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