Steering toward safety

A look at new technology concepts to overcome design issues inherent in adapting steering angle sensors for heavy-duty applications.

Steering angle sensors (SAS) have matured in the passenger car marketplace over the past 10 years with the increasing penetration of stability control systems. Their suitability in these lighter-duty applications are, overall, meeting the specifications. When these devices are selected for use in commercial vehicle applications, the inherent weaknesses with each technology become more pronounced. The design requirements for commercial vehicles are unique, typically requiring longer duty cycles, more extreme vibration, and a higher tolerance for wear over the component's lifetime.

First, it is necessary to describe various SAS technologies and the appropriateness of each of their key features when used in through-hole steering angle sensing applications. Such technologies include potentiometers, optical encoders, magnetoresistive devices, conventional Hall-effect sensors, and Piher's PST technology. Each technology should be scrutinized for suitability in its use as a through-hole steering angle device.