Automotive steering systems are designated as an important safety component, and mechanical parts used in them require high precision. Rack and pinion are widely used in steering systems, but the special support structure of the rack makes it difficult to evaluate gear meshing performance with conventional measurement methods for tooth profile error based on a datum in the workpiece, as is done with normal gears. Therefore, we proposed a unique measurement method that takes the rack support structure into account. Furthermore, we applied the measurement method to variable rack which is increasingly popular recently to improve driving stability.
Yasuhara et al. (2025) studied this question.