Displacement Measurement Based on UAV Images Using SURF-Enhanced Camera Calibration Algorithm

Displacement is an important parameter in the assessment of integrity infrastructure; thus, its measurement required a multitude guidelines or codes for structural health monitoring most countries. To develop low-cost and remote displacement technique, novel method based on unmanned aerial vehicle (UAV) digital image correlation (DIC) presented this study. First, auxiliary reference that meets requirements fabricated using selected first image. Then, speeded-up robust features (SURF) algorithm introduced to track feature points fixed areas. The least square then employed resolve homography matrix target images; then, acquired matrices are utilized calibrate deviation caused by UAV wobble. Finally, integral pixel sub-pixel matching DIC calculate object. numerical simulation results show proposed has higher calculation accuracy stability. outdoor experiment definite practicability.