Attleboro, Mass. Sensata Technologies has demonstrated several occupant sensing approaches that can help engineers design seat-belt alert systems that are more accurate and provide a better level of consumer convenience and safety.
Sensata is exhibiting a new piezoelectric sensor, as well as an existing Monocrystalline Silicon Strain Gauge (MSG) force sensor at SAE 2007 World Congress in Detroit.
The piezoelectric sensor solves the problem of traditional weight-only detection systems, which often cannot differentiate between a person or a heavy object such as a box or bag of groceries, creating false seat-belt alerts, according to the company. A piezoelectric wire, incorporated into a pad mounted under the seat cushion and providing input to an electronic module, senses the frequency response of a human and can determine the relative position of the passenger.
The piezo sensor can be integrated into a variety of seat structures, including A- or B-surface mounting, and accommodates all seat covering options including ventilated seats. A three-position sensor is available for rear seats.
Due to the sensor's ability to accurately measure weight and passenger position, this technology is also being considered for use with new Federal Motor Vehicle Safety Standard 208 classification airbag deployment systems.
Sensata is also demonstrating its MSG Occupant Weight Sensor (OWS) that uses a silicon MEMS strain gauge element glass bonded to a stainless steel diaphragm. Four MSG sensors are mounted within the seat structure to create accurate weight measures for safe airbag deployment and compliance to FMVSS208. The sensors are available in several designs: an axial or flange rigid sensor, a rigid sensor with a Stress Reduction Component (SRC), or a SRC with a flange center style.
Product information: sensors
Sensata Technologies, 1-508-236-3800, www/semsata.com