A radiation sensor comprises plural radiation sensing elements arranged along an arrangement line, a lens having an optical axis focusing radiation towards the sensing elements, and circuitry receiving the electric signal of the sensing elements and providing an output signal. The control unit specifies a trajectory of a predetermined area on which the main body unit is worn during walking based on accelerations detected by the accelerometer, calculates the temporal change amount of the specified trajectory, and determines the degree of change, which is the degree of the temporal change, based on the calculated temporal change. Example embodiment target rods may house one or more irradiation targets of varying types and phases. Additionally, this design allows each digit line to be routed on both conductor layers, for equal lengths of the array, to provide balanced impedance. The method further includes utilizing the information to determine an appropriate design for a future vehicle. Bolts with hex heads and male threaded shafts are passed through the clamps, then a slot in the frame and thence to a locking knob female threaded to allow tightening of the clamps against the bedpost.