Research status of pose detection methods of boom-type roadheader

According to principle of pose detection of boom-type roadheader, pose detection methods of roadheader respectively based on sector laser, indoor GPS (iGPS), total station, machine vision, ultra wide band (UWB) and inertial navigation were introduced. The pose detection method of roadheader based on sector laser has advantages of concise calculation, high accuracy of heading angle and X-axis (vertical direction of two sides of coal wall) coordinate measurement, but it cannot detect Y-axis (heading direction) coordinate and Z-axis (vertical direction of ground) coordinate of roadheader fuselage. The pose detection method of roadheader based on iGPS can realize full-parameter pose measurement with high detection accuracy, but effective measurement distance is small. The pose detection method of roadheader based on total station can also realize full-parameter pose measurement, but calibration and station shift are complicated. The pose detection method of roadheader based on machine vision has advantages of high measurement accuracy of cutting head position, fuselage posture of roadheader as well as X-axis and Z-axis coordinate, but it cannot detece Y-axis coordinate of roadheader. The pose detection method of roadheader based on UWB has advantages of convenient automatic station shift and high accuracy of Y-axis coordinate measurement, but Z-axis coordinate error is large. The pose detection method of roadheader based on inertial navigation has advantages of high measurement accuracy of posture angle and independent non-contact measurement process, but there is cumulative error in three-axis coordinate measurement. In order to meet practical application requirements that effective measurement distance is greater than 100 m, three-axis positioning error is less than 10 cm and posture angle error is less than 1°, it is necessary to further research combined roadheader pose detection method of machine vision, UWB and inertial navigation, so as to realize automatic, full-parameter and non-contact pose detection of roadheader.