矿用防爆相机折射成像建模与多激光束掘进设备视觉定位方法

针对防爆玻璃折射图像畸变导致井下视觉定位系统精度和稳定性不足问题，提出一种考虑玻璃折射成像机理及建模理论，利用多激光束构建井下点-线定位特征，获得非透视多激光束精确定位的新方法。依托已有平台和研究基础，研究具有多层防爆玻璃折射影响的矿用相机非中心折射成像机理，构建几何驱动的多轴矿用相机共面约束成像模型；建立矿用相机折射校准近似本质矩阵方程，以重投影量化误差最小为目标，实现矿用相机参数非线性估计与优化；以三个平行激光指向仪的出射激光点和激光线构建测量特征，建立非透视三点三线定位模型，实现掘进设备长距离稳定精确定位；建立基于距离范围和测量精度的非线性多参数优化模型，优化井下视觉定位系统方案。在所研制多激光束标靶掘进设备位姿测量平台上进行性能实验研究，验证并利用多因素耦合下矿用相机非线性成像行为，获得煤矿井下设备视觉测量系统设计准则，为高精度和鲁棒性强的井下定位系统设计奠定理论和技术基础。

Aiming at the problems of the accuracy and stability of the visual positioning system that result from the image distortion caused by the refraction of explosion-proof glass, a modeling theory considering the mechanism of glass refraction imaging is proposed, and multiple laser beams have been used to construct the point-line positioning features in coal mine, so as to obtain the precise positioning of non-perspective multiple laser beams. Based on the existing platform and research foundation, the non-central refraction imaging mechanism of underground camera with the refraction effect of multi-layer explosion-proof glass is studied, and a geometrically-driven coplanar constrained imaging model of multi-axis underground camera is constructed. The similar essential matrix equation of refraction calibration for underground camera is established, and the nonlinear estimation and optimization of underground camera parameters are realized with the goal of minimizing re-projection quantization error. The measurement features are constructed by the outgoing laser points and laser lines of three parallel laser pointing instruments, and the non-perspective three-point and three-line positioning model is established to realize the long distance stable and accurate positioning of tunneling equipment. A nonlinear multi-parameter optimization model based on the range and measurement accuracy is established to optimize the vision positioning system scheme. The performance experiments have been carried out on the position and posture measurement platform of the tunneling equipment with multiple laser beams target, and the nonlinear imaging behavior of the underground camera under the coupling of multiple factors has been verified. The design criteria of the vision measurement system for the underground equipment in coal mine are obtained, which have laid the theoretical and technical foundation for the design of the positioning system with high precision and strong robustness.