Research Results For 'Sensor'

OFF-ROUTE MINE

An off-route-mine is a form of ambush weapon which detects a passing object, and fires at it automatically. A typical example is an anti-tank rocket launcher placed on a stand, fitted with a sensor to detect a passing tank and a computer to calculate the range and course of the vehicle and then to fire the rocket at the correct time. Such a weapon can be concealed near a road and left unattended.
Research Off-Route Mine

CAMERA

A camera is a device used in photography for capturing photographic pictures or television pictures. The camera as we know it was originally known as the camera obscura, a device used for both projecting images on to paper for sketching, and on to sensitised paper for photography, in distinction from the camera lucida, which was a similar, portable device without an enclosed box, used solely for projecting an image on to paper for sketching.

Photographic cameras have been produced in a variety of forms, but the basic principal remains the same. A fast opening and closing flap, called a shutter, allows light to enter the body of the camera through a small hole, called the aperture, and fall upon a light sensitive medium; originally a paper, glass or plastic material impregnared with some chemical such as silver iodide, later an electronic light sensor.

Photographic cameras are divided into several types: compact, single lens reflex (SLR) and medium format being the most common. Compact cameras are generally simple to operate devices used to capture low quality, domestic photographs to serve as reminders of events. SLR cameras have lots of adjustable settings and detachable lenses to allow a multitude of different lenses to be fitted for long distance and close-up photography and are widely used by professional photographers. Medium format cameras use a relatively large light sensitive medium to produce very high quality large prints, and are sometimes used by portrait photographers.
Research Camera

PDS

PDS is an abbreviation for Portable Diagnostic System. It is an expert system which diagnoses faults in machinery from information received from sensors connected to the machinery. Sensor readings are compared with known data about component malfunction symptoms to diagnose faults.
Research PDS

PHOTOGRAPHY

Photography is the art, and sometimes business, of taking and also sometimes producing and printing photographs.

Early cameras operated upon the principle of allowing light reflected from a subject to fall upon a light-sensitive chemical impregnated plate, later plastic film. These plates or films were then treated with other chemicals to prevent further sensitivity to light, thereby fixing the image which was then printed. Later digital cameras evolved which used electronic light sensors to record the image in a binary digital file on a memory card.

If too much light is allowed in to the camera, the picture will be over exposed, and will look bright and indistinct. If not enough light is allowed in, the picture will be under exposed and will look dark and indistinct. It is less common for photographs to be over exposed, than under exposed.

Light is allowed in to the camera to the photograph plate, film or sensor through a quickly opening and closing door called the shutter. The size of the hole which is revealed by the shutter is known as the aperture, and is measured in F-Stops, such as F1.8, F4.5, F11 etc. Where, confusingly, the larger the F number the smaller the aperture is. Thus, F1.8 is quite a large aperture, and F11 is fairly small. A larger aperture, represented by a smaller F number, lets in more light than a smaller aperture.

The length of time for which the shutter remains open, letting light in through the aperture is often referred to as the shutter speed, and is measured in fractions of a second. Thus, a shutter speed of 500 implies that the aperture will be open for 1/500th of a second, while a shutter speed of 125 implies that the aperture will be open for 1/125th of a second. The longer the aperture remains open, the more light will enter.

How quickly the photographic plate, film or sensor reacts to the light reaching it through the aperture is known as the sensitivity of the plate, film or sensor and is measured in ISO or ASA units. The larger the ISO value, the quicker the plate, film or sensor will react to the light. Thus, a sensitivity of ASA or ISO 100 will react slower than a sensitivity of 200 or 400.

The aperture size, shutter speed and sensitivity, work together to determine the level of exposure that occurs when a picture is taken. Automatic camera settings will set these three values for you, so that the picture is properly exposed, and if it can not be properly exposed, will warn you. However, there are other effects connected with each of these three settings.

The higher the sensitivity of the photographic plate, film or sensor, the more grainy or noisy the photograph will be. Therefore, using the lowest possible sensitivity will give the best possible quality for the photograph. In order to use a low sensitivity, the subject must be as brightly lit as possible. For example a subject in bright sunshine or lit by powerful lamps or the use of a camera flash gun.

The camera's aperture size governs the depth of the photograph. The smaller the aperture is, the deeper the field of focus. Using a large aperture size will result in only the subject being in focus, objects behind and in front of the subject will be blurred. Using a small aperture will allow objects behind and in front of the subject to also be in focus. The smaller the aperture size, the further behind and in front of the subject objects will remain in focus, and by extension the easier it will be to focus upon the subject.

The most noticeable effect of the shutter speed is in reducing motion blur and camera shake. When holding a camera, particularly one with a long lens every one will quiver their hand to a greater or lesser degree. When using a zoom lens, this quivering or camera shake is much more noticeable than when using a shorter or wider angle lens. If the camera is moved, even slightly while the shutter is open, the picture will be blurred. The more the camera moves while the shutter is open, the more blurring will occur. By using a fast shutter speed, the shutter is open for less time and as such less movement affect the photograph. Similarly, if the subject being photographed moves while the image is being taken, the resulting photograph will be blurred. Using a fast shutter speed of 1/500th of a second or faster enables photographs to be taken of action shots, such as footballers in mid-movement or in the air while heading the ball. The subject's movement being slower than the speed of the shutter opening and closing which appears to freeze the moment in time.

The best way to reduce camera shake is to use a tripod. If you can not use a tripod, try resting the camera on a firm surface, such as a wall, fence post or tree. It can not be over emphasised that using a tripod will result in better photographs as every one quivers ever so slightly when taking photographs. Even activating the shutter release on the camera can slightly jar the camera. To overcome this, many photographers use a camera with automatic frame advance or sequential shooting, whereby after activating the shutter release the camera takes multiple photographs until the shutter release mechanism is released. In this way, three images may be taken automatically, the first and last will often suffer from slight camera shake due to the action of operating the shutter release mechanism, while the second image will not.
Research Photography

SHAKE REDUCTION

Shake reduction is a popular name for an image stabilisation system found in electronic cameras, whereby often a gyroscopic sensor within the body of the camera detects the very fine movement of the camera - refered to as camera shake - and aims to compensates for it by very quickly moving the camera's sensor with the camera holder's shaking motion, resulting in less blurred photographs being taken. Shake reduction is not required when the camera is mounted on a stable platform, such as a tripod, and can be a hinderance when the photographer is deliberately moving the camera, such as for example when panning the camera with a moving subject.
Research Shake Reduction

NH90 NFH

The NH90 NFH (NATO Frigate Helicopter) is one of two versions of the NH90, the 9 ton class twin engine multi-role helicopter. The primary missions of the NH90 NATO Frigate Helicopter are in the autonomous ASW anti submarine warfare and ASuW anti-surface ship warfare role. The helicopter can operate by day and night, in adverse weather and in the environment of severe ship motion. In the anti-submarine warfare role, the helicopter is capable of carrying out detection, classification, identification tracking and attack of submarines. The helicopter has a crew of three or four, the pilot and co-pilot/Tacco (the tactical co-ordinator responsible for anti-surface or anti- submarine warfare mission management) and the Senso (the helicopter sensor systems operator) in the cabin.
Research NH90 NFH

OC-135

The OC-135 is an American observation aircraft. It is a modified WC-135B. The OC-135B modifications centre around four cameras installed in the rear of the aircraft. Since its primary mission is to take pictures, most of the installed equipment and systems provide direct support to the cameras and the camera operator. Work on the aircraft also included installing an auxiliary power unit, crew luggage compartment, sensor operator console, flight following console and upgraded avionics. The interior seats 38 people including: the cockpit crew, aircraft maintenance crew, foreign country representatives and crew members from the Department of Defence's On-Site Inspection Agency. Cameras installed include one vertical and two oblique KS-87 framing cameras used for low altitude photography approximately 3,000 feet above the ground, and one KA-91 pan camera, which pans from side to side to provide a wide sweep for each picture, used for high altitude photography at approximately 35,000 feet. The Miletus camera annotation
system processes navigational, altitude, time and camera signals to annotate each picture with correct position, altitude, time, roll angle and other information. In addition, this system records every picture taken according to camera, frame and navigational position and downloads this data to a 3.5-inch floppy disk. A keyboard with trackball is the input device for operation of this system. Two Barco 12-inch VGA colour monitors display camera annotation and other camera data on screen for the sensor operator and observer use.
Research OC-135

ROOIVALK

The Denel Aviation Rooivalk is a South African two-seat missile armed attack helicopter, in service since 1999. The Rooivalk carries a comprehensive range of weaponry selected for the mission requirement, ranging from anti-armour and anti-helicopter missions to ground suppression and ferry missions. The aircraft can engage multiple targets at short and long range, utilising the nose-mounted cannon and a range of under-wing-mounted munitions. Target detection, acquisition and tracking are carried out using the nose mounted stabilised sight, TDATS. The TDATS sight is equipped with a low level television sensor, Forward Looking Infrared sensor (FLIR), autotracker, laser rangefinder and laser designator. A helmet mounted sight display (HMSD) provides the crew with a head-up display of information for nap-of-the-earth flight (NOE). The HMSD incorporates an integrated measurement system for directing an articulated weapon such as the cannon, or air-to-air missile seeker heads. The Rooivalk is armed with an articulated 20 mm F2
cannon chin mounted on the helicopter and is equipped to fire 70 mm Folding Fin Aerial Rockets (FFAR).
Rooivalk can also fire Mokopa, Hellfire and HOT 3 anti-tank missiles and can carry four air-to-air missiles such as the V3C Darter or the Mistral.
Research Rooivalk

U-2

The Lockheed U-2 (Dragon Lady) is an American single-seat, single-engine, high-altitude, unarmed, reconnaissance aircraft that entered service in 1956. The U-2 is powered by a Pratt and Whitney J75-P-13B turbojet providing a top speed of 692 kmh and a range of more than 4800 km and an endurance of 12 hours. Long, wide, straight wings give the U-2 glider-like characteristics. It can carry a variety of sensors and cameras, is an extremely reliable reconnaissance aircraft. Because of its high altitude mission, the pilot must wear a full pressure suit. The U-2 is capable of collecting multi-sensor photo, electro-optic, infrared and radar imagery, as well as performing other types of reconnaissance functions. However, the aircraft can be a difficult aircraft to fly due to its unusual landing characteristics.
Research U-2

AACSENT

AACSENT is an abbreviation for Air to Air Covert Sensor Technology
Research AACSENT

	The Probert Encyclopaedia was designed, edited and programed by Matt and Leela Probert ©1993 - 2009 The Probert Encyclopaedia Southampton, United Kingdom