Target Tracking from a UAV based on Computer Vision

This thesis presents the design and build of tracking system for a quadrotor to chase a moving target based on computer vision in GPS-denied environment. The camera is mounted at the bottom of the quadrotor and used to capture the image below the quadrotor. The image information is transmitted to computer via a video transmitter and receiver module. The target is detected by the color and contour-based detection algorithm. The desired pitch and roll angles are calculated from the position controller based on the relative position and velocity between the moving target and the quadrotor. Interface between PC and quadrotor is built by controlling the PWM signals of the transmitter for command transmission.

Three types of position controllers including PD controller, fuzzy controller and self-tuning PD controller based on fuzzy logic are designed and tested in the tracking tests. Results on the corresponding tracking performances are presented. Solutions to improving the tracking performance including the usage of optical sensor for velocity measurement and high-resolution camera for higher image quality are discussed in future work.