Magnetorheological damper with external excitation for more efficient control of vehicles’ dynamics

This article presents a new concept design for magnetorheological dampers, where the excitation circuit and magnetic field are applied from outside the magnetorheological chamber. This magnetorheological damper was designed and built to decrease the intrusive manufacturing operations and to maximize the working efficiency. The experimental tests made on the first prototype featuring this new technology was promising. The excitation of a set of 12 coils surrounding the body of the damper, by an electric current of 5 A, managed to increase the damping coefficient by up to 75%. A similar performance could be obtained by a current 9.4 times lower if the magnetic circuit is designed correctly. Compared to other devices, the actual design tolerates more the temperature elevation caused by the feeding of coils with high-intensity current, just because the heat is radiated outwards instead of being transferred directly to the magnetorheological fluid like in conventional designs. Finally, the numerical simulations made on Matlab show that the new magnetorheological damper, when mounted on a commercial vehicle, can considerably enhance its dynamic behavior and bring it back quickly to its stable position when the tires hit a bump on the road.