| 摘要 |
PURPOSE:To eliminate an influence caused by an external light, contamination of a reflecting body, etc., by calculating all the difference of two outputs out of outputs of three photodetectors provided in parallel in the right and left directions of an unmanned vehicle. CONSTITUTION:When a photodiode 11 of the center is positioned on a reflecting tape 3, running of an unmanned vehicle is started, and from each light emitting diode 21, a light is irradiated toward the floor surface containing the reflecting tape 3 and based on a reflection quantity from the reflecting tape 3 caught by photodiodes 12, 13 provided on each side part of the right and left, a running control of the unmanned vehicle is executed. Outputs of all photodiodes 11, 12 and 13 are provided to differential amplifiers 41, 42 and 43, and by each differential amplifier, the potential corresponding to a difference of the photodetecting quantities of two photodiodes is outputted, inputted to window comparators 51, 52 and 53, respectively, and compared with a set value. In this state, only when outputs of all the window comparators have become a high level, an alarm device 8 is operated. |
