A combination backrest and storage compartment for a motorcycle or the like includes a bag made of flexible material, dimensioned to fit in the space between the driver’s seat and the sissy bar of the motorcycle. A computer system may receive from an intake sensor a first tray identifier describing a first tray present on an intake transport system. The metallic reflection film has a thickness of 80 to 500. The force sensor disk comprises a variable resister that is electrically coupled to a force sensor disk cable; the force sensor disk cable is electrically coupled to a measurement resistor RM, a load resistor RL, a battery and a power switch. The electric swiveling mechanism further comprises a first swiveling mechanism and a second swiveling mechanism for controlling yaw and pitch swiveling, respectively. The management information includes navigation information for reproducing data from the recording medium, and the navigation information including region information.