A seat adjustment apparatus for adjusting a seat in a passenger compartment of a vehicle including wave sensors for transmitting waves into the passenger compartment toward the seat, receiving reflected waves from the passenger compartment and generating an output representative of the reflected waves received by the wave sensors, weight sensors associated with the seat for measuring the weight applied onto the seat and generating an output representative of the measured weight applied onto the seat and a processor for receiving the outputs from the wave sensors and the weight sensors and evaluating the seated-state of the seat based thereon. The processor directs a control unit to cause a portion of the seat to move based on the evaluation of the seated-state of the seat.