On-Site Global Calibration of Mobile Vision Measurement System Based on Virtual Omnidirectional Camera Model

Binhu Chai,Zhenzhong Wei

doi:10.3390/rs13101982

Abstract

The mobile vision measurement system (MVMS) is widely used for location and attitude measurement in aircraft takeoff and landing, and its on-site global calibration is crucial to obtaining high-accuracy measurement aimed at obtaining the transformation relationship between the MVMS coordinate system and the local-tangent-plane coordinate system. In this paper, several new ideas are proposed to realize the global calibration of the MVMS effectively. First, the MVMS is regarded as azimuth and pitch measurement equipment with a virtual single image plane at focal length 1. Second, a new virtual omnidirectional camera model constructed by three mutual orthogonal image planes is put forward, which effectively resolves the problem of global calibration error magnification when the angle between the virtual single image plane and view axis of the system becomes small. Meanwhile, an expanded factorial linear method is proposed to solve the global calibration equations, which effectively restrains the influence of calibration data error. Experimental results with synthetic data verify the validity of the proposed method.

Highlights

A new virtual omnidirectional camera model constructed by three mutual orthogonal image planes is put forward, which effectively resolves the problem of global calibration error magnification when the angle between the virtual single image plane and view axis of the system becomes small
Transforming aircraft location and attitude in the coordinate system of mobile vision measurement system (MVMS) to the local-tangent-plane (LTP) coordinate system is a primary mission that leads to obtaining the direct physical meaning parameters for users, and this is called the global calibration of MVMS
An expanded factorial linear method is proposed to obtain the linear solutions of the location and attitude, which effectively restrains the measurement matrix errors from the angles of azimuth, pitch, and the control points

Summary

Introduction

The location and attitude of aircraft play an important role in airborne remote sensing for motion parameter estimation, performance evaluation, verification of aircraft design theory, flight safety assurance, and so on [1]. The mobile vision measurement system (MVMS) is a piece of effective equipment for the dynamic measurement of location and attitude. The MVMS mainly consists of a zoom-lens camera with long-range focus length and a pan/tilt servo unit, which is usually mounted on a carrier vehicle that could be laid out flexibly on the spot according to measurement requirements. Transforming aircraft location and attitude in the coordinate system of MVMS to the local-tangent-plane (LTP) coordinate system is a primary mission that leads to obtaining the direct physical meaning parameters for users, and this is called the global calibration of MVMS

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Discussion

Conclusion