Ground robot positioning method based on multiple sensors

Abstract

The invention relates to a ground robot positioning method based on multiple sensors. The method comprises the following steps that an encoder, a camera and an IMU are mounted on a robot; a plurality of two-dimensional codes are laid on the ground as map marks; in the advancing process of the robot, an encoder odometer module fuses data of an encoder and an IMU through a Kalman filter to provide continuous inertial track plotting, and a vision-inertial navigation positioning module fuses an image, the IMU, an encoder odometer track and motion manifold constraint through a nonlinear optimization algorithm to solve the six-dimensional pose of the robot; and the two-dimensional code detection module provides global pose correction. According to the method, various data information such as environment textures, two-dimensional codes, inertia measurement and encoders are efficiently fused, different fusion strategies are adopted for different data types, and high-precision robot six-dimensional pose positioning is provided.

Description

technical field [0001] The invention relates to the field of intelligent robots, in particular to a multi-sensor-based ground robot positioning method. Background technique [0002] Robot positioning means that the robot obtains its own position and posture in the environment through information matching with the map through the collected sensor data during the movement process. Positioning is the basic module of a robot, and accurate self-positioning is a prerequisite for robot navigation. [0003] QR code positioning is a common positioning method, which is widely used in storage robots, sorting robots, etc. The QR code is laid on the ground in advance, and the robot moves on the grid composed of the QR code; the ground is photographed by the camera, and the QR code in the image is recognized to realize the global positioning of the robot. The distance between the two QR codes is located by the IMU inertial measurement unit and the encoder, thus providing continuous traj...

AI Technical Summary

Problems solved by technology

[0007] However, the "visual-inertial navigation" odometer is affected by its initial value because the integral of the IMU is affected by its initial value, and the positioning effect on the ground robot is not good.

The movement of ground robots is often relatively stable, mostly linear motion with uniform acceleration and in-situ rotation motion. This kind of motion will cause the scale information of the "visual-inertial navigation" odometer to be unobservable

The pitch and roll direction of the ground robot change very little, and it is difficult to achieve accurate observation

Images