|
Astro-inertial Guidance
Missile guidance refers to a variety of methods of guiding a missile or a guided bomb to its intended target. The missile's target accuracy is a critical factor for its effectiveness. Guidance systems improve missile accuracy by improving its Probability of Guidance (Pg). These guidance technologies can generally be divided up into a number of categories, with the broadest categories being "active", "passive", and "preset" guidance. Missiles and guided bombs generally use similar types of guidance system, the difference between the two being that missiles are powered by an onboard engine, whereas guided bombs rely on the speed and height of the launch aircraft for propulsion. History The concept of unmanned guidance originated at least as early as World War I, with the idea of remotely guiding an airplane bomb onto a target, such as the systems developed for the first powered drones by Archibald Low (The Father of Radio Guidance). In World War II, guided missiles were first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proportional Control
Proportional control, in engineering and process control, is a type of linear feedback control system in which a correction is applied to the controlled variable, and the size of the correction is proportional to the difference between the desired value ( setpoint, SP) and the measured value (process variable, PV). Two classic mechanical examples are the toilet bowl float proportioning valve and the fly-ball governor. The proportional control concept is more complex than an on–off control system such as a bi-metallic domestic thermostat, but simpler than a proportional–integral–derivative (PID) control system used in something like an automobile cruise control. On–off control will work where the overall system has a relatively long response time, but can result in instability if the system being controlled has a rapid response time. Proportional control overcomes this by modulating the output to the controlling device, such as a control valve at a level which avoids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contrast Seeker
Optical contrast seekers, or simply contrast seekers, are a type of missile guidance system using a television camera as its primary input. The camera is initially pointed at a target and then locked on, allowing the missile to fly to its target by keeping the image stable within the camera's field of view. The first production missile to use a contrast seeker was the AGM-65 Maverick, which began development in the 1960s and entered service in 1972. The system has not been widely used, as other guidance technologies like laser guidance and GPS have become more common, but the same basic concept is used in cameras to track objects, including the systems used to aim the laser designators. Contrast seekers should be distinguished from television guidance systems, in which a live television signal is broadcast to the launch platform, which then uses manual direction to attack the target. Examples of TV guidance include the Martel and AGM-62 Walleye. The term "contrast contour" is som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-aircraft
Anti-aircraft warfare, counter-air or air defence forces is the battlespace response to aerial warfare, defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It includes surface based, subsurface ( submarine launched), and air-based weapon systems, associated sensor systems, command and control arrangements, and passive measures (e.g. barrage balloons). It may be used to protect naval, ground, and air forces in any location. However, for most countries, the main effort has tended to be homeland defence. NATO refers to airborne air defence as counter-air and naval air defence as anti-aircraft warfare. Missile defence is an extension of air defence, as are initiatives to adapt air defence to the task of intercepting any projectile in flight. In some countries, such as Britain and Germany during the Second World War, the Soviet Union, and modern NATO and the United States, ground-based air defence and air defence aircraft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Homing
Infrared homing is a passive weapon guidance system which uses the infrared (IR) light emission from a target to track and follow it seamlessly. Missiles which use infrared seeking are often referred to as "heat-seekers" since infrared is radiated strongly by hot bodies. Many objects such as people, vehicle engines and aircraft generate and emit heat and so are especially visible in the infrared wavelengths of light compared to objects in the background. Infrared seekers are passive devices, which, unlike radar, provide no indication that they are tracking a target. That makes them suitable for sneak attacks during visual encounters or over longer ranges when they are used with a forward looking infrared or similar cuing system. Heat-seekers are extremely effective: 90% of all United States air combat losses over the past 25 years have been caused by infrared-homing missiles. They are, however, subject to a number of simple countermeasures, most notably by dropping flares beh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Guidance
Laser guidance directs a robotics system to a target position by means of a laser beam. The laser guidance of a robot is accomplished by projecting a laser light, image processing and communication to improve the accuracy of guidance. The key idea is to show goal positions to the robot by laser light projection instead of communicating them numerically. This intuitive interface simplifies directing the robot while the visual feedback improves the positioning accuracy and allows for implicit localization. The guidance system may serve also as a mediator for cooperative multiple robots. Examples of proof-of-concept experiments of directing a robot by a laser pointer are shown on video. Laser guidance spans areas of robotics, computer vision, user interface, video games, communication and smart home technologies. Commercial systems Samsung Electronics Co., Ltd. may have been using this technology in robotic vacuum cleaners since 2014. Google Inc. applied for a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semi-active Radar Homing
Semi-active radar homing (SARH) is a common type of missile guidance system, perhaps the most common type for longer-range Air-to-air missile, air-to-air and surface-to-air missile systems. The name refers to the fact that the missile itself is only a passive radar, passive detector of a radar signal—Radar illumination, provided by an external ("offboard") source—as it reflects off the target (in contrast to active radar homing, which uses an active radar transceiver). Semi-active missile systems use bistatic radar, bistatic continuous-wave radar. The NATO Multiservice tactical brevity code, brevity code for a semi-active radar homing missile launch is Fox (code word), Fox One. Concept The basic concept of SARH is that since almost all detection and tracking systems consist of a radar system, duplicating this hardware on the missile itself is redundant. The weight of a transmitter reduces the range of any flying object, so passive systems have greater reach. In addition, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Targeting Radar
This is a list of different types of radar. Detection and search radars Search radars scan great volumes of space with pulses of short radio waves. They typically scan the volume two to four times a minute. The waves are usually less than a meter long. Ships and planes are metal, and reflect radio waves. The radar measures the distance to the reflector by measuring the time of the roundtrip from emission of a pulse to reception, dividing this by two, and then multiplying by the speed of light. To be accepted, the received pulse has to lie within a period of time called the ''range gate''. The radar determines the direction because the short radio waves behave like a search light when emitted from the reflector of the radar set's antenna. Search * Early Warning (EW) Radar Radar Systems ** Ground Control Intercept (GCI) Radar ** Airborne Early Warning (AEW) ** Airborne ground surveillance (AGS) ** Over-the-Horizon (OTH) Radar *Target Acquisition (TA, TAR) Radar Systems ** Surface ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
R-77
The Vympel NPO R-77 missile (NATO reporting name: AA-12 Adder) is a Russian active radar homing beyond-visual-range air-to-air missile. It is also known by its export designation RVV-AE. It is the Russian counterpart to the American AIM-120 AMRAAM missile. The R-77 was marked by a severely protracted development. Work began in the 1980s, but was not completed before the Soviet Union fell. For many years, only the RVV-AE model was produced for export customers. Production was further disrupted when the Russian invasion of Ukraine resulted in a Ukrainian arms embargo against Russia, severing supply chains. The Russian Air Force finally entered the R-77-1 (AA-12B) into service in 2015. It was subsequently deployed by Su-35S fighters in Syria on combat air patrols. The export model of the R-77-1 is called RVV-SD. Development Work on the R-77 began in 1982. It represented Russia's first multi-purpose missile for tactical and strategic aircraft for fire-and-forget use against aircraf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AIM-120 AMRAAM
The AIM-120 Advanced Medium-Range Air-to-Air Missile, or AMRAAM (pronounced ), is an American beyond-visual-range air-to-air missile (BVRAAM) capable of all-weather day-and-night operations. It is 7 inches (18 cm) in diameter, and employs active transmit-receive radar guidance instead of semi-active receive-only radar guidance. It is a fire-and-forget weapon, unlike the previous generation Sparrow missiles which needed guidance from the firing aircraft. When an AMRAAM missile is launched, NATO pilots use the brevity code Fox Three. more than 14,000 had been produced for the United States Air Force, the United States Navy, and 33 international customers. The AMRAAM has been used in several engagements, achieving sixteen air-to-air kills in conflicts over Iraq, Bosnia, Kosovo, India, and Syria. Origins AIM-7 Sparrow MRM The AIM-7 Sparrow medium range missile (MRM) was purchased by the US Navy from original developer Hughes Aircraft in the 1950s as its first operatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire-and-forget
Fire-and-forget is a type of missile guidance which does not require further external intervention after launch such as illumination of the target or wire guidance, and can hit its target without the launcher being in line-of-sight of the target. This is an important property for a guided weapon to have, since a person or vehicle that lingers near the target to guide the missile (using, for instance, a laser designator) is vulnerable to attack and unable to carry out other tasks. Generally, information about the target is programmed into the missile just prior to launch. This can include coordinates, radar measurements (including velocity), or an infrared image of the target. After it is fired, the missile guides itself by some combination of gyroscopes and accelerometers, GPS, onboard active radar homing, and infrared homing optics. Some systems offer the option of either continued input from the launch platform or fire-and-forget. Fire-and-forget missiles can be vulnerable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angular Resolution
Angular resolution describes the ability of any image-forming device such as an optical or radio telescope, a microscope, a camera, or an eye, to distinguish small details of an object, thereby making it a major determinant of image resolution. It is used in optics applied to light waves, in antenna theory applied to radio waves, and in acoustics applied to sound waves. The colloquial use of the term "resolution" sometimes causes confusion; when an optical system is said to have a high resolution or high angular resolution, it means that the perceived distance, or actual angular distance, between resolved neighboring objects is small. The value that quantifies this property, ''θ,'' which is given by the Rayleigh criterion, is low for a system with a high resolution. The closely related term spatial resolution refers to the precision of a measurement with respect to space, which is directly connected to angular resolution in imaging instruments. The Rayleigh criterion shows th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Astro-inertial Guidance"){kind=icon}
