Estimation and Control of a Quadrotor Vehicle Using Monocular Vision and Moiré Patterns

We present the vision-based estimation and control of a quadrotor vehicle using a single camera relative to a novel target that incorporates the use of moiré patterns. The objective is to acquire the six degree of freedom estimation that is essential for the operation of vehicles in close proximity to other craft and landing platforms. A target contains markers to determine its relative orientation and locate two sets of orthogonal moiré patterns at two different frequencies. A camera is mounted on the vehicle with the target in the field of view. An algorithm processes the images, extracting the attitude and position information of the camera relative to the target utilizing geometry and four single-point discrete Fourier transforms on the moiré patterns. The position and yaw estimations with accompanying control techniques have been implemented on a remote-controlled quadrotor. The flight tests conducted prove the system’s feasibility as an option for precise relative navigation for indoor and outdoor operations.