A parking assist system (PAS) calculates the distance between the vehicle and an object (an obstacle or another vehicle) based on the time it takes for ultrasound emitted by a sensor reflecting from an object and coming back, and communicates the information to a driver for safe parking. As PAS permeates the automobile market, there was a potential demand for a small and highly reliable pin connection type sensor capable of automated mounting, from the viewpoints of lower assembly cost and quality assurance.
There was a limitation for downsizing pin-connector type ultrasonic sensors, since its pin connector had to be placed outside of the sensor unit via a support in order to reduce property degradation from its own vibration. Murata has succeeded in coming up with the structure to internalize this support within the sensor, making it possible to downsize the unit while maintaining characteristics equivalent with existing lead wire type sensors.
Also, introducing a flexible substrate for connecting a piezoelectric ceramic device and a pin connector inside the sensor, and automating the connecting process, stabilized the characteristics and improved reliability and productivity. Small pin-connector type ultrasonic sensors are advantageous for meeting the requirement to improve the resistance characteristics for electromagnetic noise, due to recent advancement in digital signal processing of PAS.
Lately, automakers are hard at work to introduce advanced driving assistance systems (ADAS) in automobiles. One of the features is detecting pedestrians and automobiles in blind spots for increased safety. Current PAS technology may be implemented to this feature, and its key device is an ultrasonic sensor. While PAS requires the detection distance of about 2m, ADAS will require about 10m. Murata will develop a high sensitivity ultrasonic sensor by hybridizing ceramic material technology, high-precision ceramic processing technology and high efficiency ultrasonic sensing technology to meet the market needs.