A CPU of a control device provided in a traveling unit causes a display to display information indicating that it is necessary to mount an energy absorbing unit capable of absorbing collision energy in a case where it is determined that a vehicle cabin forming unit is for the purpose of carrying a person, and causes the display to display information indicating that it is not necessary to mount the energy absorbing unit in a case where it is determined that the vehicle cabin forming unit is not for the purpose of carrying a person.