Research on pose measurement system of cantilever roadheader based on laser target tracking

The accurate and rapid measurement of the roadheader pose is the premise and foundation of intelligent heading in coal mine roadway. The existing cantilever roadheader pose measurement has the problem of non-absolute pose measurement, low measurement precision, complex arrangement, or only a few pose parameters being measured. The measurement can not meet the intelligent heading requirement. In order to solve the above problems, based on the pose measurement method of the cantilever roadheader based on laser target tracking, a pose measurement system of cantilever roadheader based on laser target tracking is designed. The system consists of a laser tracking device and a laser target. The laser tracking device is arranged behind the roadway, emits laser to the laser target arranged on the cantilever roadheader fuselage, and tracks the movement of the laser target. By solving the conversion matrix between coordinate systems such as laser tracking device, laser target, roadheader and roadway, six absolute pose parameters such as heading direction position, offset, height, deviation angle, pitch angle and roll angle can be measured. The full parameter real-time measurement of absolute pose of cantilever roadheader in roadway coordinate system is realized. The error influence factors of the system are analyzed, and the error distribution law is obtained by simulation. With the increase of heading distance, the pose measurement error of roadheader changes within a certain range. The measurement errors of offset and height increase linearly. Within the measurement range of 5-80 m, the measurement errors of the deviation angle, pitch angle and roll angle of the roadheader are less than 1.4, 1, 0.03° respectively. The measurement error of the heading direction position is less than 5 mm, and the measurement errors of offset and height are less than 20 mm. Using the crawler robot chassis, an experimental system for pose measurement is built. The pose measurement experiment is carried out in the simulated roadway. The results show that the measurement errors of the heading direction position, offset and height are less than 5 mm. The measurement error of the deviation angle is less than 1°. The measurement error of the pitch angle is less than 0.6°. And the measurement error of the roll angle can be ignored. The results are consistent with the simulation results, which proves the reliability of the system.