To provide a vehicle obstruct on-road detection device capable of measuring the height of the obstacle form the road surface correctly even when the distance of a forward gazing point of the laser radar is far.

The vehicle obstruct on-road detection device comprises: the laser radar 1 provided on a vehicle for making the forward gazing point distance which is the distance between the road irradiated point of the laser light and the vehicle variable by changing the dip angle of the laser light; the first height operation part 5f for operating the height of the obstacle from the road surface by detecting the distance from the laser radar to the obstacle from the reflected wave reflected from the irradiated obstacle; the second height operation part 5g for operating the height of the obstacle from the road surface by detecting the length of shadow of the obstacle irradiated with the laser light, and from the length of the shadow and the dip angle of the laser light for the vehicle; and the switching part 5e for switching the operation of height of the obstacle from the road surface between the first operation part 5f and the second operation part 5g.

COPYRIGHT: (C)2007,JPO&INPIT