Title: Minimizing the mass of the wheel of a human-powered electro-hybrid ultralight vehicle using CAx techniques

Authors: M. Zuger, U. Josi, A. Fuchs

Addresses: Berne Institute of Technology, Ingenieurschule Berne HTL (ISBE), Morgartenstrasse 2c, CH-3014 Berne, Switzerland. ' Berne Institute of Technology, Ingenieurschule Berne HTL (ISBE), Morgartenstrasse 2c, CH-3014 Berne, Switzerland. ' Berne Institute of Technology, Ingenieurschule Berne HTL (ISBE), Morgartenstrasse 2c, CH-3014 Berne, Switzerland

Abstract: Ultralight vehicles that combine the low specific energy consumption of bicycles with the safety, comfort and payload capacity of faired vehicles might be the short-distance commuter vehicles of tomorrow. The ultralight vehicle (ULM BE 2000) that is being developed at the Beme Institute of Technology, Switzerland, is a hybrid: it is propelled by human as well as electric power. The power needed to climb hills and to accelerate the vehicle from standstill is mainly electric, whereas on the flat the contribution from human power is also important. Using the wheel of the ultralight vehicle as an example, we describe a method of mass minimization. First, during the design process, geometries were evaluated for both wheel-rigidity and ease of manufacturing. Then the mass of the chosen geometry was minimized by varying several parameters with CAD/CAE software and by assuming gravitational, lateral and braking loads. Constraints of the minimization were deformation and stress limits. Secondly, to verify the minimization, the final CAD-model of the wheel was analysed with FEM.

Keywords: CAx techniques; CADCAE software; CAD; CAE; electro-power; human power; rider-bicycle systems; ultralight vehicles; vehicle dynamics; tricycles; vehicle design; hybrid electric vehicles; HEVs; hybrid vehicles; mass minimisation; vehicle wheels; deformation; stress; computer-aided design; FEM; finite element method.

DOI: 10.1504/IJVD.1997.062065

International Journal of Vehicle Design, 1997 Vol.18 No.5, pp.433 - 441

Published online: 29 May 2014 *

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