Abstract
We have developed a hybrid magnetorheological transmission in total artificial hearts with maglev motors. The
developed transmission has small size and the sufficient transmission performance, but it generated radial magnetic force that may cause touchdown in the total artificial heart. In this paper, we proposed a novel hybrid magnetorheological transmission utilizing axial and radial magnetic flux to reduce radial magnetic force. First, we showed the relationship between output rotational speed and magnetic flux density distribution in each direction. Second, we designed the hybrid magnetorheological transmission that permanent magnets were incorporated in both output shaft and yoke. Analyzed results showed that axial and radial magnetic flux density were 0.038 and 0.091 T at 0 A, respectively. From experimental results, the difference between input and output rotational speed changed from 9 rpm to 228 rpm when we applied current at 1 A. And the measured radial magnetic force of the proposed transmission was 82.1% smaller than that of the previous transmission using only radial magnetic flux.
