Ground surface estimation method, measurement area display system, and crane

A measurement region display system comprising:

• a data acquisition section including a laser scanner, the laser scanner acquiring point cloud data by radiating laser on a measurement region;
• a data processing section that performs arithmetic processing on the acquired point cloud data;
• and
• a data display section, wherein:
• the data processing section
• acquires the point cloud data from the data acquisition section, and calculates an altitude value of a radiation point from the point cloud data;
• divides the measurement region into a plurality of grids, calculates a center-of-gravity position of each of the grids and an average altitude value of the point cloud data in each of the grids, and sets the center-of-gravity position at the average altitude value of the point cloud data in each of the grids as a position of a representative point for each of the grids;
• recognizes one grid and another adjacent grid of the plurality of grids as a continuous region when a difference in altitude value between the representative point of the one grid and the representative point of the other adjacent grid is equal to or less than an inter-grid threshold, the continuous region being a region where the one grid and the other adjacent grid are continuous;
• estimates the continuous region having a largest number of the grids among the continuous regions as a ground surface;
• estimates a non-adjacent continuous region as the ground surface when a difference between an average altitude value of the representative point of the grids in the non-adjacent continuous region and an average altitude value of the representative point of the grids in a predetermined range of the continuous region estimated as the ground surface is equal to or less than an inter-region threshold, the non-adjacent continuous region being the continuous region not adjacent to the continuous region estimated as the ground surface, the average altitude value of the representative point of the grids in the non-adjacent continuous region being calculated for each of the non-adjacent continuous regions, the average altitude value of the representative point of the grids in the predetermined range of the continuous region estimated as the ground surface being calculated;
• and
• displays the continuous region estimated as the ground surface on the data display section, the continuous region estimated as the ground surface being distinguished from the continuous region other than the continuous region estimated as the ground surface.

A crane comprising:

• a swivel base;
• a boom provided on the swivel base;
• a laser scanner attached to the boom and acquiring point cloud data;
• a control apparatus that performs arithmetic processing on the acquired point cloud data;
• and
• a display apparatus, wherein:
• the point cloud data for each position of the laser scanner when radiating laser is acquired by laser radiation while the laser scanner is caused to move in accordance with a swiveling operation of the swivel base, an extending and retracting operation of the boom, and/or a luffing operation of the boom, and
• the control apparatus
• acquires the point cloud data for each position of the laser scanner when radiating the laser, superimposes the point cloud data for each position of the laser scanner when radiating the laser based on each position and attitude of the laser scanner when radiating the laser, and calculates an altitude value of a radiation point;
• divides a measurement region of the laser scanner into a plurality of grids, calculates a center-of-gravity position of each of the grids and an average altitude value of the point cloud data in each of the grids, and sets the center-of-gravity position at the average altitude value of the point cloud data in each of the grids as a position of a representative point for each of the grids;
• recognizes one grid and another adjacent grid of the plurality of grids as a continuous region when a difference in altitude value between the representative point of the one grid and the representative point of the other adjacent grid is equal to or less than an inter-grid threshold, the continuous region being a region where the one grid and the other adjacent grid are continuous;
• estimates the continuous region having a largest number of the grids among the continuous regions as a ground surface;
• estimates a non-adjacent continuous region as the ground surface when a difference between an average altitude value of the representative point of the grids in the non-adjacent continuous region and an average altitude value of the representative point of the grids in a predetermined range of the continuous region estimated as the ground surface is equal to or less than an inter-region threshold, the non-adjacent continuous region being the continuous region not adjacent to the continuous region estimated as the ground surface, the average altitude value of the representative point of the grids in the non-adjacent continuous region being calculated for each of the non-adjacent continuous regions, the average altitude value of the representative point of the grids in the predetermined range of the continuous region estimated as the ground surface being calculated;
• and
• displays the continuous region estimated as the ground surface on the display apparatus, the continuous region estimated as the ground surface being distinguished from the continuous region other than the continuous region estimated as the ground surface.