Abstract: The flexible error and parameter error of jumbo boom ends in tunnel construction are calibrated respectively from the aspect of main factors that affecting the positioning accuracy of the boom end, so as to improve the positioning accuracy of the working jumbo boom. The flexible deformation is measured by the response surface method, and the response surface is fitted with the least square method to obtain the deflection deformation value of the boom and the cross-section corner deformation value. The kinematic parameters of the working jumbo boom are obtained by direct calibration method, and the calibration scheme of the anchor trolley based on the total station is proposed. At the same time, the experimental verification of the calibration results is carried out. The experimental results show that: (1) The absolute positioning errors of the X direction, Y direction and Z direction at the boom end are reduced by 59.09%, 77.03% and 75.67%, respectively, and the total distance error is reduced by 79.46%. (2) The maximum absolute positioning error of the boom end is 0.069 9 m, the average value is 0.023 6 m, and the mean square error is 0.016 8, which can better meet the actual positioning requirements and perform well in subsequent engineering applications.

Key words: tunnel working jumbo, jumbo boom, positioning accuracy, flexible deformation calibration, parameter calibration, tunnel rock-drilling jumbo