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The track line suffers from track irregularity, subgrade settlement, rail surface defects, and gauge distortion. Measuring the track geometry quality plays an important role in rail administrations to safe operation and track maintenance. In order to meet the requirements of track daily inspection, this article describes a comprehensive detection system for the track geometry, which is designed by four cameras, an inclinometer, and an inertial measurement unit. Moreover, the detection system has the characteristics of simple structure, automatic detection, and multiple measurement parameters. First, to measure track alignment and irregularity, a multisensing calibration method is established to fuse visual sensors and inertial sensors. An accelerometer and a Kalman filter are used to eliminate accumulated unrealistic drifts of accelerometer and gyroscope. Second, to measure the rail surface defects and gauge, the model of laser and machine vision is deduced to obtain the coordinate values in a unified coordinate system, and an improved iterative closest point method is developed to improve the matching accuracy. Finally, a series of experiments is carried out to validate the measuring performance. The results indicate that the proposed method can accurately measure the track geometry, with the maximum deviations of track alignment, track irregularity, rail defects, and gauge that are less than 0.5, 0.4, 0.3, and 0.1 mm, respectively. The detection system is not only simple in structure but also has multiple detection parameters, which is especially suitable for track daily maintenance. [ABSTRACT FROM AUTHOR]