Rotation of the symmetric gear in the ABP bath. (A)–(C) Snapshots at sequential times of the simulation. The solid cyan circles are ABPs. The symmetric gear is marked with a blue arrow and the black curved arrow indicates the direction of rotation. (A) The aggregation of ABPs around the gear just before the start of rotation. Typical time sequences of $\omega t$ for the three rotating states: URS (D), TS (E) and RRS (F). (G) The corresponding accumulative angles $∆\theta t$. (A)–(D) D_r = 0.01, (E) D_r = 0.007, (F) D_r = 0.02, and $F_{\text{a}}=8$, $\varphi =0.15$ for all.