Dynamic Characteristics of Self-Eliminating-Backlash 3K Planetary Gear Train with Flexure-based Carrier

3K Planetary Gear Train (PGT) is a promising gear reducer for collaborative robots and humanoid robots due to its high reduction ratio and high bidirectional efficiencies. To improve the accuracy of the 3K PGT further, a Self-Eliminating-Backlash 3K (SEB-3K) PGT is proposed, which eliminates the backlash automatically through the designed flexure-based carrier. However, the effects of the designed carrier on the 3K PGT need to be further analyzed. As such, the lumped parameter dynamic model considering the preload of the carrier is established for the SEB-3K PGT. Based on the dynamic model, the output velocity fluctuation and the lost motion of the SEB3K PGT versus the preload of the carrier are simulated. From the results, the working states of the SEB-3K PGT are divided into five zones by the preload of the carrier and the reason is analyzed, which provides a reference for the parameter design of the flexure-based carrier.