Abstract—Magneto-Rheological rotary brakes are widely used as passive torque actuators for stability in exoskeletons, humanoid robots, robot manipulators and haptic devices. An ideal MR brake should provide high braking torque performance with small outside dimensions. Among many MR brake designs in the literature, multi-pole design types have superior torque characteristics. Multi-pole MR brakes can be designed with different number of poles. Increasing the number of poles will improve the torque performance since it increases the number of magnetic circuit chains. On the other hand, this restricts the space required for the coils. Thus, the higher pole number necessitates less number of turn in each coil. In this paper, two design configurations of 4-pole with 225 coil-turns and 6-pole with 150 coil-turns are selected for the same electrical resistance in terms of power consumption (4-pole 225 coil-turns = 6-pole 150 coil-turns = 900 coil-turns). These two designs are analyzed and compared in the same outside dimensions (27 mm radius 85 mm length) by conducting analytical modelling, finite element analysis (FEA) and design optimization. The simulation results show that the 6-pole design configuration provides higher torque performance than 4-pole configuration although both have the same coil-turns in total.
Index Terms—Magneto-rheological fluid brake, multi-pole, rotary brake.
The authors are with the Department of Mechanical Engineering of Suleyman Demirel University, Isparta 32260, Turkey (corresponding author: Ozgur Baser; e-mail: ozgurbaser@sdu.edu.tr, mehmet.alper.demiray@gmail.com).
[PDF]
Cite: Ozgur Baser and Mehmet Alper Demiray, "Comparison of 4-Pole with 225 Coil-Turns and 6-Pole with 150 Coil-Turns Multi-pole Inner Coil Rotary MR Brake Designs," International Journal of Materials, Mechanics and Manufacturing vol. 5, no. 3, pp. 200-204, 2017.
![[Click]](http://www.ijmmm.org/img/ijmmm_v7n2_inspec%28IET%29_indexscreenshot.jpg){kind=link}