Speaker
Description
The aim of the ongoing research at our department in the field of magnetometers is the development of a compact modular magnetometric system operating with amorphous strips and microwires, used as a core. The motivation is in long-term research, development and testing of magnetometers with different types of control and processing electronics. The use of FPGA or CPLD devices for control and sensing electronics of relaxation and time-difference magnetometers has been verified.
The research has led over the years to the development of two types of fluxgate magnetometers. First of them is, the VEMA magnetometer developed and realized by the researchers at the Faculty of Aeronautics in cooperation with EDIS vvd. company. The second one, considering the current trend of reducing dimensions and power consumption in order to increase the performance of sensoric systems, considers the use of microwires as the core of the magnetometer due to their small size, low power consumption and good sensing properties [1,2].
Both types of magnetometric systems work with the conversion of magnetic field measurement to time measurement. For accurate time measurement in out experiments, the TDC7200 (time to digital converter) circuit designed for the LIDAR with the resolution of 55 ps has been used to measure the relaxation time and the time difference of our magnetometric systems. Generally, the device to measure the time would be a microcontroller, but in the case of 3 and more channels the advantage of synchronous timing would be lost. For this case, instead of a microcontroller, it is proficient to use a CPLD or an FPGA device, which, in addition to controlling the sensing and excitation electronics, also serves to control the TDC7200 circuits.
The paper builds on the knowledge obtained from the previously performed measurements in details described in [3] while the FPGA device is used to control the transistor bridge using optocouplers with timing adjustments. The paper presents results that were achieved during experiments focused on the improvement of the current devices’ precision and noise characteristics.
Acknowledgements
This research was funded by the ITMS2014+ 313011AUP1, 313011T557, APVV-18-0248, APVV-17-0184, KEGA 045TUKE-4/2022 and VEGA 1/0101/22 projects.
References
[1] Olivera et al., “Microwire-Based Sensor Array for Measuring Wheel Loads of Vehicles,” Sensors, vol. 19, no. 21. MDPI AG, p. 4658, Oct. 26, 2019. doi: 10.3390/s19214658.
[2] V. Zhukova, P. Corte-Leon, M. Ipatov, J. M. Blanco, L. Gonzalez-Legarreta, and A. Zhukov, “Development of Magnetic Microwires for Magnetic Sensor Applications,” Sensors, vol. 19, no. 21. MDPI AG, p. 4767, Nov. 02, 2019. doi: 10.3390/s19214767.
[3] P. Lipovský et al., “Relax-Type Magnetometer with Direct Optocoupler Relaxation,” Acta Physica Polonica A, vol. 137, no. 5. Institute of Physics, Polish Academy of Sciences, pp. 681–683, May 2020. doi: 10.12693/aphyspola.137.681.
