Patent ID: 9733358
Date: 2017-08-15
CPC Classifications: G01S,G08B

Claim:
1. A laser scanning sensor comprising: a laser distance meter which emits a laser beam, and which measures a distance to at least one object present in a direction of the laser beam, based on a time until the laser beam reflects off the at least one object and returns to the laser distance meter; a scanning mechanism unit which changes a measurement direction by the laser distance meter; a distance information acquisition unit which defines a detection area and sequentially acquires distance information containing at least one distance measured in each measurement direction in the detection area, by allowing the scanning mechanism unit to change the measurement direction and allowing the laser distance meter to make a periodic measurement; a distance information interpolation unit which carries out an interpolation process for each measurement direction, wherein the interpolation process is effected when a piece of said distance information acquired by the distance information acquisition unit is judged to correspond to an unintended object that exists at a shorter distance than an object to be originally detected, and when complementation of the piece of said distance information corresponding to the unintended object is judged to be possible based on a piece of said distance information acquired in an adjacent measurement direction or a piece of said distance information acquired at a previous measurement cycle, and wherein the interpolation process comprises replacing the piece of said distance information in the measurement direction corresponding to the unintended object with an interpolated value based on the piece of said distance information acquired in the adjacent measurement direction at a same measurement cycle or with an interpolated value based on the piece of said distance information acquired in the measurement direction at the previous measurement cycle; a judgment unit which extracts a portion of said distance information that may correspond to an object or a human body, the distance information having been acquired by the distance information acquisition unit and having been subjected to the interpolation process by the distance information interpolation unit as required, and which judges whether the extracted portion of said distance information corresponds to an object or a human body, based on a sequential movement status regarding the extracted portion of said distance information; and an alarm signal output unit which outputs an alarm signal if the judgment unit confirms presence of an object or a human body.