The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Investigation of the principles of visually guided flight in insects is offering novel, computationally elegant solutions to challenges in machine vision and robot navigation. Insects perform remarkably well at seeing and perceiving the world and navigating effectively in it, despite possessing a brain that weighs less than a milligram and carries fewer than 0.01% as many neurons as ours does. Although...
This paper presents the development and flight testing of a novel and efficient view-based method for the navigation and control of rotorcraft unmanned aerial vehicles (UAVs) in unknown, GPS-denied, outdoor environments. At the core of our system is the Image Coordinates Extrapolation (ICE) algorithm which estimates the UAV 3D position and velocity in real-time by computing the pixel-wise difference...
This paper describes a novel view-based method using panoramic images to perform local homing in outdoor environments. This holistic algorithm makes uses of difference images (in relation to a reference snapshot) to build an image reference frame centred at the home position. The currently experienced view at any local position is then projected onto this reference frame to determine the image coordinates...
We describe a guidance system for achieving automatic landing of a fixed‐wing aircraft in unstructured outdoor terrain, using onboard video cameras. The system uses optic flow information for sensing and controlling the height above the ground, and information on the horizon profile, also acquired by the vision system for stabilizing roll and controlling pitch, and additionally, if required, for the...
This study describes a novel method for estimating the strength and direction of the local wind field from a mobile airborne platform. An iterative optimisation is derived that allows the properties of the wind field to be determined from successive measurements of the heading direction and ground track of the aircraft only. We have previously described methods for estimating these parameters using...
This study describes a novel method for automatically obtaining the attitude of an aircraft from the visual horizon. A wide-angle view of the environment, including the visual horizon, is captured and the input images are classified into fuzzy sky and ground regions using the spectral and intensity properties of the pixels. The classifier is updated continuously using an online reinforcement strategy...
This study describes a novel method for automatically obtaining the attitude of an aircraft from the visual horizon. A wide-angle view of the environment, including the visual horizon, is captured and the input images are classified into fuzzy sky and ground regions using the spectral and intensity properties of the pixels. The classifier is updated continuously using an online reinforcement strategy...
This study describes a novel, vision-based system for guidance of UAVs. The system uses two coaxially aligned cameras, each associated with a specially-shaped reflective surface, to obtain stereo information on the height above ground and the distances to potential obstacles. The camera-mirror system has the advantage that it remaps the world onto a cylindrical co-ordinate system that simplifies and...
There is considerable interest in designing guidance systems for UAVs that use passive sensing (such as vision), rather than active sensing which can be bulky, expensive and stealth-compromising. Here we describe an optical sensor, based partly on principles of insect vision and optic flow analysis, for measurement and control of height above the ground. A video camera is used in conjunction with...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.