Selective control mechanisms of microrobots have attracted significant attention from researchers. So far, selective control within multiple/swarm magnetic microrobots has been achieved with many strategies, such as utilizing locally specified magnetic fields, applying electrostatic anchoring, taking the advantages of geometry/wettability heterogeneity of the microrobots, etc. Using the step-out behavior of helical microrobots driven by a rotating magnetic field, researchers have proposed a mathematical model for multihelical motor that can be selectively controlled. Based on this model, we developed a micromotor that consists of three geometrically heterogeneous helices that can be selectively driven within a specific narrow frequency range. This type of micromotor shows bi-direction motion capability and has the potential to be used as an actuation unit for multiple types of functional micromechanisms.