Method and system for volume determination using a structure from motion algorithm

Abstract

Volume determining method for an object (1), particularly a stock pile, on a construction site, comprising –  moving a mobile camera (8) along a path (10) around the object (1) while orienting the camera (8) repeatedly or continuously, onto the object (1), –  in the course of this, capturing a series of images of the object (1) with the camera (8), the series comprising a plurality of images captured from different points on the path (10) and with different orientations of the camera (8), the series being represented by an image data set collected thereby, –  performing a structure from motion evaluation with a defined algorithm using the series of images and generating a point cloud spatial representation comprising a surface of the object (1) therefrom, –  scaling the spatial representation with help of a known absolute reference regarding scale, the scale being imaged by the camera (8) together with the object (1), –  defining a ground surface for the object (1) and applying it onto the spatial representation and –  calculating and outputting the absolute volume of the object (1) based on the scaled spatial representation and the defined ground surface.

Description

technical field [0001] The present invention relates to a method and system for determining the volume of an object on a construction site. Background technique [0002] On construction sites it is often necessary to determine the volume of objects such as stockpiles or hollow spaces such as potholes, interstices or mines. [0003] A traditional method for determining such volumes is to scan the object with a measuring device such as a laser scanner, total station, stereo camera or a set of fixed mounted cameras. Since from one station only a part of the stockpile can be measured, while other surface points are blocked, it is necessary to have measuring devices at at least three different locations relative to, for example, the stockpile so that the stockpile can be measured in combination. the entire surface. The stockpile is captured from each station, ie the spatial position of the surface point of the stockpile is measured relative to the measuring device. Next, combi...

AI Technical Summary

Problems solved by technology

The main disadvantage of such an approach lies in the fact that cameras such as laser scanners, total stations, stereo cameras or multiple cameras are expensive hardware and need to be operated and positioned by a technician.

In addition, it is time consuming to set up such measuring devices in three different positions and to determine these positions at least relative to each other

In some cases, however, such an expenditure of time and money is relatively crude because it does not require high accuracy of position measurements performed by geodetic devices such as total stations and of the resulting volume determination. value would be sufficient and somewhat wasteful

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