A planetary gear motor assembly opens and closes a shutter door on a coin dispensing mechanism. The method selects a modulation method and an antenna mode for optimizing energy consumption when signals are transmitted and received in consideration of a network operation mode, a channel environment, Quality of Service, and the like, and transmits and receives signals using the modulation method and antenna mode. This process provides a steel casting with increased wear life, characterized by a duplex microstructure containing ferrite plus carbon in solution in austenite known as ausferrite.