Three-dimensional distance measuring method and device

Abstract

The invention relates to a three-dimensional distance measuring method and device, and particularly relates to a three-dimensional distance measuring method and device for a mobile robot, belonging to the technical field of environmental perception of mobile robots. The three-dimensional distance measuring device comprises a light source, a reflector, a collecting lens, a lantern slide, a projection objective, a camera and an image processor, wherein the light source, the reflector, the collecting lens, the lantern slide and the projection objective form a projection system, spot patterns at equal intervals on the lantern slide are projected to a space in front of the mobile robot, an image measuring system formed by the camera and the image processor measures the diameter of each projection spot in a field of view, and thus the object distance at the projection spot can be figured out. According to the technical scheme provided by the invention, three-dimensional distance measurement can be performed without a three-dimensional scanning mechanism, and the device is simple in structure, high in measurement speed and low in cost, is free of a safety problem of a laser distance measuring device and can be used in an occasion with high requirements on environmental perception precision and measurement speed.

Description

technical field [0001] The invention relates to a three-dimensional ranging method and a device thereof, in particular to a three-dimensional ranging method and a device for a mobile robot, and belongs to the technical field of mobile robot environment perception. Background technique [0002] Distance measurement is the necessary basis for mobile robots to perceive the environment and complete other advanced tasks such as autonomous navigation, obstacle avoidance, map generation, and environment modeling. Ranging technologies currently used for mobile robots are: [0003] (1) Binocular vision ranging. A binocular vision measurement system is composed of two cameras fixed to each other, and the depth of the scene is recovered according to the parallax of the same scene imaged on the two cameras, so as to obtain the distance information. The binocular vision measurement method is very simple in principle and can be used for three-dimensional distance measurement. However, d...

AI Technical Summary

Problems solved by technology

Ultrasonic sensors are small in size and low in price, and have been widely used in mobile robots. However, there are still obvious shortcomings in practical applications of ultrasonic ranging: ultrasonic waves have a large energy attenuation when propagating in the air, and the maximum measurement distance is limited; The large beam angle makes it difficult to determine the exact position of the reflected target point, so ultrasonic ranging technology can only be used in occasions that do not require high environmental perception accuracy, such as just knowing whether there is a large obstacle ahead

The advantage of laser ranging is high accuracy, which is suitable for occasions that require high environmental perception accuracy. The disadvantage is that the system is complex and costly, and it is difficult to popularize and apply it in the field of mobile robots.

To measure the distance of objects in three-dimensional space, a three-dimensional scanning device is required, which greatly increases the volume, complexity and cost of the system

In addition, the pulsed laser beam is a monochromatic light source with very concentrated energy. If it is directly irradiated to the human eye during scanning and distance measurement, it will cause serious damage to the human eye.

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