An intelligent system for temperature monitoring and brake drum cooling

Abstract

Brakes convert the kinetic energy of the moving vehicle into heat energy due to friction between fixed and moving brake parts. Frequent applications of the brakes will cause overheating in brake parts, which could generate the lubricating layer between frictional parts and result in a temporary reduction or complete loss of braking power of a vehicle. Several brake cooling methods have been proposed in the literature to solve this problem, but the effective brake cooling is still a challenging task in trucks. The objective of this research is to develop an intelligent system for temperature monitoring and active cooling in drum brakes for heavy utility trucks. The air is used as the medium of the cooling system. The buildup heat is dissipated by use of air blow across the brake elements. The cooling system incorporates an automatic controller. A specifically designed air compressor is used to discharge air with a high flow rate. Temperature is measured by using an infra-red thermal sensor. The air cooling is turned ON when the brake drum temperature is higher than a threshold value and is switched OFF once the temperature is lower than another threshold. This self-regulating controller and efficient air compressor play an integral role in the cooling system. The second research project is to develop a piezoelectric energy harvesting system to provide power for infra-red temperature monitoring sensors. A new energy harvesting model is proposed to generate power from the ambient vibration of the vehicle. A moving vehicle generates vibrations with different frequencies. A general piezoelectric system is efficient mainly around its resonance frequency. By systematic experimental tests, a new energy harvesting system is proposed to improve power generating capacity over a wider vibrational frequency range. The energy harvesting circuit stores power using piezoelectric transducer into battery, which in turn to charge temperature sensors. The effectiveness of the proposed energy harvesting methodology and system is verified experimentally under different excited frequencies.