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Title: Steering geometry and caster measurement

Book ·
OSTI ID:5686684

The purpose of this paper is to define the caster angle of a steerable vehicle wheel to be referenced to the thrust line of the non-steerable wheels. A further purpose is to derive and characterize an optimal method of measuring caster which can be implemented in a practical manner. Recent years have seen the development of the ''total alignment'' concept, which relates the toe angles of the steerable vehicle wheels to the thrust line of the non-steerable wheels. Increased sophistication of vehicle suspension systems has made this more important, while advances in alignment measurement instrumentation have incorporated the concept and assumed the corresponding computational burden. Referencing caster to the thrust angle is part of the total alignment concept, but caster of a steerable wheel is difficult to measure. It is the angle between the vertical and the projection of the invisible steering axis onto a vertical plane containing the thrust line of the vehicle. It is not easy to attach measuring devices to a projection of an invisible axis. Indirect measurement methods are available that are very accurate, if they are implemented properly and certain restrictions are observed.

OSTI ID:
5686684
Report Number(s):
TP-850219
Country of Publication:
United States
Language:
English