December 2023
Improving the Response of Accelerometers for Automotive Applications by Using LMS Adaptive Filters
Wilmar Hernandez,Jesús De Vicente,Oleg Sergiyenko andEduardo Fernández
1Department of Circuits and Systems, EUIT de Telecomunicación, Universidad Politécnica de Madrid (UPM), Campus Sur UPM, Ctra. Valencia km 7, Madrid 28031, Spain
2Department of Applied Physics, ETSI Industriales, Universidad Politécnica de Madrid, Calle José Gutierrez Abascal 2, Madrid 28006, Spain
3Institute of Engineering, Autonomous University of Baja California, Mexicali, Baja California, Mexico
4EUIT de Telecomunicación, Universidad Politécnica de Madrid (UPM), Campus Sur UPM, Ctra. Valencia km 7, Madrid 28031, Spain
*Author to whom correspondence should be addressed.
Abstract
In this paper, the least-mean-squares (LMS) algorithm was used to eliminate noise corrupting the important information coming from a piezoresisitive accelerometer for automotive applications. This kind of accelerometer is designed to be easily mounted in hard to reach places on vehicles under test, and they usually feature ranges from 50 to 2,000 g (where is the gravitational acceleration, 9.81 m/s2) and frequency responses to 3,000 Hz or higher, with DC response, durable cables, reliable performance and relatively low cost. However, here we show that the response of the sensor under test had a lot of noise and we carried out the signal processing stage by using both conventional and optimal adaptive filtering. Usually, designers have to build their specific analog and digital signal processing circuits, and this fact increases considerably the cost of the entire sensor system and the results are not always satisfactory, because the relevant signal is sometimes buried in a broad-band noise background where the unwanted information and the relevant signal sometimes share a very similar frequency band. Thus, in order to deal with this problem, here we used the LMS adaptive filtering algorithm and compare it with others based on the kind of filters that are typically used for automotive applications. The experimental results are satisfactory.
Keywords: piezoresistive accelerometer; 4-order band-pass digital Butterworth filter; LMS adaptive filter