Acoustic FEA Analysis and Modification for Robot Joint BLDC Motor

Abstract

We developed a small BLDC motor for ROBOT joint. But The motor made an abnormal acoustic noise. To find the reasons, We made an electromagnetic analysis, a modal analysis and a acoustic analysis. After simulations, we found the reason of acoustic noise. An electromagnetic force has 3500 Hz component, Motor housing also has 3500 Hz component. Because of them, The motor made an abnormal noise. To reduce the noise, We made a design modification of end plates. We thickened the depth of plates. After that, We again made simulations. the noise is reduced from 54 dB to 33 dB. To reduce an acoustic noise, We made coupled analysis, Electromagnetic, Structural, acoustic. We found the reason of noise, to reduce the noise, we modified the design of housing. the noise level was reduced.