Study on the Method of Measuring the Preceding Vehicle Distance Based on Trilinear Method

A method of measuring the preceding vehicle distance based on trilinear method is proposed in the paper. According to the theory and method of the computer vision, three mutually non-coincident parallel lines have same vanishing point and different slopes on imaging plane. Without iteration and optimization calculation, an analytic expression of the external parameters of a camera¿vanishing point and imaging slopes can be established through mathematical derivation according to pin-hole imaging model. Based on the preceding vehicle detected in the lane and calibration of intrinsic parameters of the camera, through those extrinsic parameters and perspective projection geometry the preceding vehicle distance can be measured.