Hardware Design For Self-Validating Pressure Sensor Based On DSP

Sensors are the sources of acquiring information and play a big part in the industrial production. Once out of function, it will cause serious damage. Traditional sensors can only output measured value, but can not validate whether they are in normal condition or not. In order not to affect the production, calibration offline is usually taken to avoid malfunction. However, it takes more time and energy. Under the circumstances, the concept of self-validating sensor is put forward. It is able to not only work out measured values and uncertainty, but also carry out online assessment on its condition and validate whether it is a function failure or not; and if it fails to operate normally, it will diagnose the type of the malfunction. Adjustments or changes of sensors can be made according to its state, consequently it will cut the times of adjustment and reduce the risks of lethal malfunction.The present paper is based on the related theories of self-validating sensor with the design of the hardware platform based on double DSPs(TMS320F2812 and TMS320C6713), which is served for measuring gas pressure. The article firstly introduce the concept of self-validating sensor and the research condition for the time being,and give a description of the related arithmetic used in self-validating pressure sensor. Then the hardware system which consists mainly of signal-conditioning circuits, the signal acquiring and processing circuits and etc. is presented in detail. Furthermore, the paper give an account of the software design for TMS320F2812 including ADC sampling control, preprocessing for sampling data, achieving self-validation algorithm in control of TMS320C6713 and communication with Host. At last, the system test is conducted with the accomplishment of calibration and fault diagnosis test, testing system performances and making further improvement by the testing results. The final testing results testify that the system is able to reach the goal as expected and provides the foundation for practical production.