Magneto-Mechanical Coupling Analysis of Automobile Brake by Wire System Based on Giant-Magnetostrictive Actuator

Addressing the drawbacks of traditional automotive braking systems, including long hydraulic lines, heavy weight, and slow response speed, a new type brake by wire system based on giant-magnetostrictive material is proposed, which consists of giant-magnetostrictive actuator module and mechanical drive module. In this paper, CATIA software is used to establish a three-dimensional model of the brake. In order to verify the reliability of the model, giant-magnetostrictive actuator is taken as the research object, and COMSOL software is used to simulate different working conditions of automobile braking. A Magneto-mechanical coupling model was established and Magneto-mechanical coupling analysis of the actuator was carried out. The simulation results show that the aluminum shell material is superior to the 45 steel shell material. The inductance direction of the actuator is approximately elliptical from top to bottom, with uniform distribution of magnetic flux density and stress. The output stress is 5e4N/m2, and the maximum elongation is 0.1071mm. Finally, the driving efficiency of GMA was verified on an optical isolation platform, and comparative experiments were conducted before and after optimization using instruments such as laser displacement samplers, Tesla meters, and force sensors. The experimental results indicate that by optimizing the housing material and structure of the actuator, the displacement increased from 0.05188mm to 0.1003mm, magnetic induction increased from 42.9mT to 79.9mT, resulting in an increase of 41.6% and 42.7% respectively, and the maximum output force was 4752.3N. It makes a certain contribution to the application of GMA to automotive braking field and further proves the effectiveness of GMA in the application of automobile brake by wire system.