To provide a selection assist device of an automatic transmission capable of providing a selective lever operation force characteristic corresponding to a request, by expanding the flexibility of a layout by miniaturization of a selective lever, while enabling range switching operation in fail by the mechanical connection of the selective lever and a selection position-switching device.
A controller 3 has a first driving command value arithmetic operation part 31 for arithmetically operating a driving command basic value so that relative displacement approaches 0, and a driving state determining part 32 for determining whether an assist actuator 2 is put in a driving state or a driving prohibiting state from a relative displacement quantity. The driving state determining part 32 changes to the driving prohibiting state from the driving state when detecting that the relative displacement vibrates.
NAGAMURA KENSUKE
NAGANO MASAHARU
KOBAYASHI SHINYA
