Development Of Small Size And High Pressure Sensor For ESP System

ESP is in short of Electronic Stability Program which is a new type of automotive active safety systems. ESP can ensure the driving state stability during the car speeding and braking and steering. Today, ESP has become the preferred configuration in automotive active safety program.The characteristics of the ESP system with a pressure sensor is analyzed in this paper. The mainstream pressure sensor types are studied in nowadays. The final design scheme is selected by the condition of features for the ESP system. The pressure base design, interface design and circuit design are focused. It is discussed in detail of the generation mechanism of the stress in the manufacturing process about this sensor. We find the proper stress relief process method through theoretical analysis, finite element simulation. Eeventually we made a prototype and finished comprehensive routine test and a road test and other tests a series of experimental verification, which is in line with the requirements of the ESP system. The paper obtained the complete design. The project has a good practical value. The following main highlight of work is included.(1) Microfused sensor type for automotive use is selected. Structural design pressure of the base is carried out. We analyze the thickness of the diaphragm R angle, impact, aperture sensitivity, overload characteristics, and ultimately the best optimized pressure diaphragm size parameters by finite element stress model. Finally we design the optimal sintering process, which made the micro-sensors matching the best output characteristic sensitivity and high overload capacity.(2) Several different measures of eliminating the residual stress inside is proposed. Different measures to reduce and eliminate the residual stress mechanism and effects are different for Microfused sensor. We selected some of the most effective measures to eliminate stress,which have achieved good results.(3) The conditioning circuit is finally selected in line with the project requirements through a variety of integrated signal conditioning circuitry on the market in-depth analysis and screening. And the EMC design is considerd, which is a basic work for the routine test.(4) The pressure sensor Developed for the Automotive ESP system has two characteristics of miniaturization and high-range structural. And finally we verified the functionality, performance, reliability and stability of the pressure sensor are in line with the ESP system design requirements through a series of experiment.