US Patent 7643940 Obstacle detecting apparatus

An obstacle detecting apparatus includes sensors and a control device. The sensors detect an obstacle and are connected to the control device through a bus. The control device includes communication error determination and detection means. The communication error determination means determines an occurrence of a communication error if communication with the sensors is impossible for a preset error determination time period. The communication error detection means detects the communication error. The communication error determination means sets in advance, as the error determination time period, a preset first error determination time period in the case of the first communication with the sensors and a preset second error determination time period in the case of communication with the sensors after the first communication with the sensors is normally performed. The first error determination time period and the second error determination time period are set so as to be different.