A Multiline Laser Vision Sensor Array-Driven Overall-Wheel-Profile 3-D Reconstruction and Measurement

Existing wheelset measurement methods primarily rely on one or several single-line lasers, which provide only limited information. Their measurement reliability and accuracy are insufficient to meet the requirements for high-speed train wheelset measurements. To accurately measure a wheel’s parameters online, we propose a novel 3-D reconstruction framework driven by a multiline laser vision sensor array. For local 3-D profile reconstruction, we propose multiline laser calibration, local joint calibration, and moving multitarget joint calibration to achieve the local stitching of multiline laser profiles. For global 3-D profile reconstruction, a global dynamic calibration method is proposed to concatenate local wheel 3-D profiles with varying positions and poses to a complete wheel 3-D profile. Field experimental results show maximum errors of 0.15 mm for flange height, 0.21 mm for flange thickness, and 0.38 mm for diameter. To our knowledge, this is the highest accuracy achieved in the measurement of wheelset geometric parameters.