A Review of the State-of-the-Art of Angular Rate Sensors 2000-01-2668
In today's automotive market, rollover protection systems are drawing an increasing attention. Unlike in conventional frontal and side impact events where linear accelerometers are used to detect the crash severity and make decision on deployment/non-deployment of the air bag restraint systems, rollover events require a new detection method using angular rate sensors. In the past, various angular rate sensors have been used in navigation systems to calculate pitch angle, or in camcorders for image stabilization. These sensors work at a low dynamic operating range, i.e. less than 100 degrees/sec. Angular rate sensors in automotive applications demand a higher dynamic capacity greater than 250 degrees/sec. (or °/s).
This paper reviews automotive grade angular rate sensors currently being introduced for rollover protection system applications. In addition, various detection devices ranging from basic bubble sensing to newly developed sensors using micro-machined technology are also reviewed. The principle of Coriolis force used in the angular rate sensors is described. Pros and cons of each sensor type are discussed. Test methods to evaluate angular rate sensor performance and some typical sample data are also presented.