|
VASCAR
VASCAR (Visual Average Speed Computer And Recorder) is a type of device for calculating the speed of a moving vehicle. The first VASCAR device was created in 1966 by Arthur Marshall. It is used by police officers to enforce speed limits, and may be preferred where radar or lidar is illegal, such as some jurisdictions in Pennsylvania, or to prevent detection by those with radar detectors. Operation A VASCAR unit uses a stopwatch and a simple computer. An operator records the moments that a vehicle passes two fixed objects (such as a white circle or square painted on the road) that are a known distance apart. The vehicle's average speed is then calculated by dividing the distance between the points by the time taken to travel between them. The mean value theorem implies that at some time between the measurements the vehicle's speed must be equal to its average speed. VASCAR can be used from a moving or stationary vehicle or helicopter or other aerial platform. The target vehicle ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VASCAR Enforced
VASCAR (Visual Average Speed Computer And Recorder) is a type of device for calculating the speed of a moving vehicle. The first VASCAR device was created in 1966 by Arthur Marshall. It is used by police officers to enforce speed limits, and may be preferred where radar or lidar is illegal, such as some jurisdictions in Pennsylvania, or to prevent detection by those with radar detectors. Operation A VASCAR unit uses a stopwatch and a simple computer. An operator records the moments that a vehicle passes two fixed objects (such as a white circle or square painted on the road) that are a known distance apart. The vehicle's average speed is then calculated by dividing the distance between the points by the time taken to travel between them. The mean value theorem implies that at some time between the measurements the vehicle's speed must be equal to its average speed. VASCAR can be used from a moving or stationary vehicle or helicopter or other aerial platform. The target vehicle ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speed Limit Enforcement
Speed limits are enforced on most public roadways by authorities, with the purpose to improve driver compliance with speed limits. Methods used include roadside speed traps set up and operated by the police and automated roadside 'speed camera' systems, which may incorporate the use of an automatic number plate recognition system. Traditionally, police officers used stopwatches to measure the time taken for a vehicle to cover a known distance. More recently, radar guns and automated in-vehicle systems have come into use. A worldwide review of studies found that speed cameras led to a reduction of "11% to 44% for fatal and serious injury crashes". The UK Department for Transport estimated that cameras had led to a 22% reduction in personal injury collisions and 42% fewer people being killed or seriously injured at camera sites. The ''British Medical Journal'' recently reported that speed cameras were effective at reducing accidents and injuries in their vicinity and recommended w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar Detector
A radar detector is an electronic device used by motorists to detect if their speed is being monitored by police or law enforcement using a radar gun. Most radar detectors are used so the driver can reduce the car's speed before being ticketed for speeding. In general sense, only emitting technologies, like doppler RADAR, or LIDAR can be detected. Visual speed estimating techniques, like ANPR or VASCAR can not be detected in daytime, but technically vulnerable to detection at night, when IR spotlight is used. There are no reports that piezo sensors can be detected. LIDAR devices require an optical-band sensor, although many modern detectors include LIDAR sensors. Most of today's radar detectors detect signals across a variety of wavelength bands: usually X, K, and Ka. In Europe the Ku band is common as well. The past success of radar detectors was based on the fact that radio-wave beams can not be narrow-enough, so the detector usually senses stray and scattered radiation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odometer
An odometer or odograph is an instrument used for measuring the distance traveled by a vehicle, such as a bicycle or car. The device may be electronic, mechanical, or a combination of the two (electromechanical). The noun derives from ancient Greek , ''hodómetron'', from , ''hodós'' ("path" or "gateway") and , ''métron'' ("measure"). Early forms of the odometer existed in the ancient Greco-Roman world as well as in ancient China. In countries using Imperial units or US customary units it is sometimes called a mileometer or milometer, the former name especially being prevalent in the United Kingdom and among members of the Commonwealth. History Classical Era Possibly the first evidence for the use of an odometer can be found in the works of the ancient Roman Pliny (NH 6. 61-62) and the ancient Greek Strabo (11.8.9). Both authors list the distances of routes traveled by Alexander the Great (r. 336-323 BC) as by his bematists Diognetus and Baeton. However, the high ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SPECS (speed Camera)
SPECS is an average speed measuring speed camera system introduced in 1999. It is one of the systems used for speed limit enforcement in the United Kingdom. SPECS was originally manufactured by Speed Check Services Limited, from which it takes its name. The company was acquired by Vysionics in 2010, which in turn was acquired by Jenoptik in 2014. About SPECS cameras SPECS cameras operate as sets of two or more cameras installed along a fixed route that can be from 75 metres (246 feet). Maximum distance was 10 km with SPECS1 (SVDD) but with the event of SPECS3 became unlimited although legal requirements limit the maximum practical distance. They work by using an automatic number plate recognition (ANPR) system to record a vehicle's front number plate at each fixed camera site. As the distance is known between these sites, the average speed can be calculated by dividing this by the time taken to travel between two points. The cameras use infrared photography, allowing the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Automatic Number Plate Recognition
Automatic number-plate recognition (ANPR; see also #Other names, other names below) is a technology that uses optical character recognition on images to read vehicle registration plates to create vehicle location data. It can use existing closed-circuit television, road-rule enforcement cameras, or cameras specifically designed for the task. ANPR is used by police forces around the world for law enforcement purposes, including to check if a vehicle registration, vehicle is registered or Vehicle licence, licensed. It is also used for electronic toll collection on road pricing, pay-per-use roads and as a method of cataloguing the movements of traffic, for example by highways agencies. Automatic number-plate recognition can be used to store the images captured by the cameras as well as the text from the license plate, with some configurable to store a photograph of the driver. Systems commonly use infrared lighting to allow the camera to take the picture at any time of day or night ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doppler Effect
The Doppler effect or Doppler shift (or simply Doppler, when in context) is the change in frequency of a wave in relation to an observer who is moving relative to the wave source. It is named after the Austrian physicist Christian Doppler, who described the phenomenon in 1842. A common example of Doppler shift is the change of pitch heard when a vehicle sounding a horn approaches and recedes from an observer. Compared to the emitted frequency, the received frequency is higher during the approach, identical at the instant of passing by, and lower during the recession. The reason for the Doppler effect is that when the source of the waves is moving towards the observer, each successive wave crest is emitted from a position closer to the observer than the crest of the previous wave. Therefore, each wave takes slightly less time to reach the observer than the previous wave. Hence, the time between the arrivals of successive wave crests at the observer is reduced, causing an increa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LIDAR
Lidar (, also LIDAR, or LiDAR; sometimes LADAR) is a method for determining ranges (variable distance) by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver. It can also be used to make digital 3-D representations of areas on the Earth's surface and ocean bottom of the intertidal and near coastal zone by varying the wavelength of light. It has terrestrial, airborne, and mobile applications. ''Lidar'' is an acronym of "light detection and ranging" or "laser imaging, detection, and ranging". It is sometimes called 3-D laser scanning, a special combination of 3-D scanning and laser scanning. Lidar is commonly used to make high-resolution maps, with applications in surveying, geodesy, geomatics, archaeology, geography, geology, geomorphology, seismology, forestry, atmospheric physics, laser guidance, airborne laser swath mapping (ALSM), and laser altimetry. It is also used in control and navigation for som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light-emitting Diode
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresponding to the energy of the photons) is determined by the energy required for electrons to cross the band gap of the semiconductor. White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device. Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared (IR) light. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics. The first visible-light LEDs were of low intensity and limited to red. Early LEDs were often used as indicator lamps, replacing small incandescent bulbs, and in seven-segment displays. Later developments produced LEDs available in visible, ultraviolet (UV) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nixie Tube
A Nixie tube ( ), or cold cathode display, is an electronic device used for displaying numerals or other information using glow discharge. The glass tube contains a wire-mesh anode and multiple cathodes, shaped like numerals or other symbols. Applying power to one cathode surrounds it with an orange glow discharge. The tube is filled with a gas at low pressure, usually mostly neon and often a little mercury or argon, in a Penning mixture. Although it resembles a vacuum tube in appearance, its operation does not depend on thermionic emission of electrons from a heated cathode. It is hence a cold-cathode tube (a form of gas-filled tube), and is a variant of the neon lamp. Such tubes rarely exceed even under the most severe of operating conditions in a room at ambient temperature. Vacuum fluorescent displays from the same era use completely different technology—they have a heated cathode together with a control grid and shaped phosphor anodes; Nixies have no heater or control ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dashboard
For business applications, see Dashboard (business). A dashboard (also called dash, instrument panel (IP), or fascia) is a control panel set within the central console of a vehicle or small aircraft. Usually located directly ahead of the driver (or pilot), it displays instrumentation and controls for the vehicle's operation. Etymology Originally, the word ''dashboard'' applied to a barrier of wood or leather fixed at the front of a horse-drawn carriage or sleigh to protect the driver from mud or other debris "dashed up" (thrown up) by the horses' hooves. The first known use of the term (hyphenated as ''dash-board'', and applied to sleighs) dates from 1847. Commonly these boards did not perform any additional function other than providing a convenient handhold for ascending into the driver's seat, or a small clip with which to secure the reins when not in use. When the first "horseless carriages" were constructed in the late 19th century, with engines mounted beneath the drive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toggle Switch
In electrical engineering, a switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. The most common type of switch is an electromechanical device consisting of one or more sets of movable electrical contacts connected to external circuits. When a pair of contacts is touching current can pass between them, while when the contacts are separated no current can flow. Switches are made in many different configurations; they may have multiple sets of contacts controlled by the same knob or actuator, and the contacts may operate simultaneously, sequentially, or alternately. A switch may be operated manually, for example, a light switch or a keyboard button, or may function as a sensing element to sense the position of a machine part, liquid level, pressure, or temperature, such as a thermostat. Many specialized forms exist, such as the toggle switch, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.png "Click for more on -> Dashboard")
