Matthew A. Garratt

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Experiments from biology suggest that the sensing of image motion or optic flow in insects provides a means of determining the range to obstacles and terrain. When combined with a measure of ground speed from another sensor such as GPS, optic flow can be used to provide a measure of an aircraft’s height above terrain. We apply this principle to the control(More)
Autonomous control of a low-cost micro air vehicle (MAV) is considered, using a single camera and inertial measurement unit. Integration of loom is used to determine the approximate height during takeoff and landing, and to provide an initial height for hover. Contrary to most optic-flow-based approaches that lack positional feedback, a “snapshot” paradigm(More)
This paper presents an integrated GPS/INS/Vision navigation system for Unmanned Aerial Vehicles (UAVs). A CCD (ChargeCoupled Device) video camera and laser rangefinder (LRF) based vision system, combined with inertial sensors, provides the information on the vertical and horizontal movements of the UAV (helicopter) relative to the ground, which is critical(More)
The problem of developing a reliable system for sensing and controlling the hover of a Micro Air Vehicle (MAV) using visual snapshots is considered. The current problem is part of a larger project, which is developing an autonomous MAV, controlled by vision only information. A new algorithm is proposed that uses a stored image of the ground, a snapshot(More)
Autonomously operating unmanned aerial vehicles (UAV) have a great potential for many applications such as reconnaissance, mapping and surveillance. Whilst needing low cost and light weight navigation systems in their implementations, sensors like GPS or low cost inertial sensors can’t separately provide either the complete set of information or the(More)
Neural Network Identification (NNID) for modeling the dynamics of a miniature Eagle helicopter is presented in this paper. Off-line and on-line identification is carried out for both coupled and decoupled dynamics of the helicopter from the flight test data. For both the cases, identification results and the error statistics are provided. The off-line(More)
We present a novel vision system for estimating the 6DoF relative pose of an UAV from a shipdeck. The vision system aims to detect the international landing target using the edge information of the target to perform line segment mapping, feature point clustering and filtering. A novel target-shape evaluation scheme is developed to fuse the measurements.(More)
Image registration is a fundamental technique in image processing. It is used to spatially align two or more images that have been captured at different times, from different sensors, or from different viewpoints. There have been many algorithms proposed for this task. The most common of these being the well-known LucasKanade and Horn-Schunk approaches.(More)
The combination of a camera and an Inertial Measurement Unit (IMU) has received much attention for state estimation of Micro Aerial Vehicles. In contrast to many map based solutions, this paper focuses on optic flow (OF) based approaches which are much more computationally efficient. The robustness of a popular OF algorithm is improved using a transformed(More)