US Patent 7175133 Wing driving apparatus

A wing driving apparatus is made up of a flight controller part for generating a drive signal, first and second servo actuators, a first controller unit having a first drive circuit, and a second controller unit having a second drive circuit. The first controller unit includes a follower signal generator circuit for generating a follower signal. The second servo actuator includes a solenoid valve for invalidating a control to the second serve actuator based on the drive signal from the second drive circuit in response to the follower signal, whereby the second second servo actuator follows the steering wing when the first drive circuit is able to operate the first servo actuator to drive the steering wing.