Remote control

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For other uses, see Remote control (disambiguation).
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Image:Television remote control.jpg

A remote control is an electronic device used for the remote operation of a machine.

The term, sometimes abbreviated to “the remote” and also called "bufter", is most commonly used to refer to a remote control for televisions or other consumer electronics such as stereo systems and DVD players, and to turn on and off a mains plug. Remote controls for these devices are usually small handheld objects with an array of buttons for adjusting various settings such as television channel, track number, and volume. In fact, for the majority of modern devices with this kind of control, the remote contains all the function controls while the controlled device itself only has a handful of essential primary controls. Most of these remotes communicate to their respective devices via infrared (IR) signals and a few via radio signals. They are usually powered by small AAA or AAAA size batteries.

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History

One of the earliest examples of remote control was developed in 1893 by Nikola Tesla, and described in his patent, Template:US patent, named Method of and Apparatus for Controlling Mechanism of Moving Vehicle or Vehicles. The first remote-controlled model airplane flew in 1932. The use of remote control technology for military purposes was worked intensively during the Second World War, one result of this was the German Wasserfall missile. The first remote intended to control a television was developed by Zenith Radio Corporation in the early 1950s. The remote — unofficially called “Lazy Bones” — used a wire to connect to the television set. To improve the cumbersome setup, a wireless remote control was created in 1955. The remote called “Flashmatic” worked by shining a beam of light onto a photoelectric cell. Unfortunately, the cells did not distinguish between light from the remote and light from other sources. The Flashmatic also required that the remote control be pointed accurately at the receiver...

Image:Zenith SpaceCommand.jpg In 1956 Robert Adler developed “Zenith Space Command”, a wireless remote. It was mechanical and used ultrasound to change the channel and volume. When the user pushed a button on the remote control it clicked and struck a bar, hence the term “clicker”. Each bar emitted a different frequency and circuits in the television detected this noise. The invention of the transistor made possible cheaper electronic remotes that contained a piezoelectric crystal that was fed by an oscillating electric current at a frequency near or above the upper threshold of human hearing, though still audible to dogs. The receiver contained a microphone attached to a circuit that was tuned to the same frequency. Some problems with this method were that the receiver could be triggered accidentally by naturally occurring noises, and some people, especially young women, could hear the piercing ultrasonic signals. There was even a noted incident in which a toy xylophone changed the channels on these types of TVs since some of the overtones from the xylophone matched the remote’s ultrasonic frequency.

The impetus for a more complex type of television remote control came in the late 1970s with the development of the Ceefax teletext service by the BBC. Most commercial remote controls at that time had a limited number of functions, sometimes only four: next station, previous station, increase or decrease volume. This type of control did not meet the needs of teletext sets where pages were identified with three-digit numbers. A remote control to select teletext pages would need buttons for each number from zero to nine, as well as other control functions, such as switching from text to picture, and the normal television controls of volume, station, brightness, colour intensity and so on. Early teletext sets used wired remote controls to select pages but the continuous use of the remote control required for teletext quickly indicated the need for a wireless device. So BBC engineers began talks with one or two television manufacturers which led to early prototypes in around 1977-78 that could control a much larger number of functions. ITT was one of the companies and later gave its name to the ITT protocol of infrared communication. [1]

In the early 1980s, when semiconductors for emitting and receiving infrared radiation were developed, remote controls gradually switched to that technology which, as of 2006, is still widely used. Remotes using radio technologies, such as Bose Audio Systems and those based on Bluetooth also exist.

By the early 2000s, the amount of consumer electronic devices in most homes greatly increased. According to the Consumer Electronics Association, an average American home has four remotes. To operate a home theater as many as five or six remotes may be required, including one for cable or satellite receiver, VCR or digital video recorder, DVD player, TV and audio amplifier. Several of these remotes may need to be used sequentially, but, as there are no accepted interface guidelines, the process is increasingly cumbersome. Many specialists, including Jakob Nielsen [2], a renowned usability specialist and Robert Adler, the inventor of the modern remote, note how confusing, unwieldy and frustrating the multiplying remotes have become. To that end, designers of the TiVo remote control replaced the standard columns of buttons on a black rectangle with a distinctive peanut shaped design that has been well received by its users [3]. This design, which has spawned several imitations, is likely to change the way consumer electronics designers approach the remote.

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Types of remote controls

Image:Remote controlled car.jpg Remote or radio control exist for many other devices as well: scale model airplanes, helicopters and other radio-controlled models are popular children’s toys; many robots are remotely controlled, especially those which are designed for doing perilous tasks; and some state of the art military fighter jets are operated by remote control.

Alternatively, universal remote controls combine multiple remotes into one, usually with some sort of switch or button saying which device the remote is currently controlling. Universal remotes run from inexpensive basic models to a US$700 Linux-powered model from Sony [4]. The first Universal Remote Control was developed by William Russell McIntyre in the mid 1980s, while employed at North American Philips Consumer Electronics Corporation (Magnavox/Sylvania/Philco). McIntyre’s software design was awarded patents, since it was the first remote which could be pointed at an electronic device and learn its operational controls. The next step in remote controls is a Home Control Panel. These remote controls not only work on television or home entertainment sets, but also let you control other electronic appliances as electronic curtains, lightswitches and security cameras. Some of the latest Home Control Panels will also let you stream audio and are able to make photos.

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Remote-controlled firearms are sometimes used to hunt birds and other animals. In 2005, legislation was introduced in Virginia to ban this practice. HB 2273 provided[5]:

No person shall operate, provide, sell, or use or offer to operate, provide, sell, or use any device or service that allows a person, not physically present, to remotely control a firearm, weapon, or device to hunt any live animal or bird.
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Technique

Image:Control-remote-spectrum.png

Most control remotes for electronic appliances use a near infrared diode to emit a beam of light that reaches the device. This light is invisible to the human eye but carries signals that are detected by the appliance.

With a single channel remote control the presence of a carrier signal can be used to trigger a function. For multi-channel remote controls more sophisticated procedures are necessary: one consists of modulating the carrier with signals of different frequency. After the demodulation of the received signal, the appropriate frequency filters are applied to separate the respective signals. Nowadays digital procedures are more commonly used.

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Usage

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Industry

Remote control is used for controlling substations, pump storage power stations and HVDC-plants. For these systems often PLC-systems working in the longwave range are used.

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Weapons

Remote-controlled weapons have been used since World War II.

Also known as a "Smitchik", refering the remotes that controlled the most destructive weapons. The term "Smitchik", of Yiddish descent, is a generally accepted synonym for a Television Remote Control.

The term "Smitchik Factor" refers to the amount of inherent destructive capability of a weapon or person.

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Space

Remote control technology is also used in space travel, for instance the Russian Lunokhod vehicles were remote-controlled from the ground. Direct remote control of space vehicles at greater distances from the earth is not practical due to increasing signal delay times.

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See also

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External links

da:Fjernbetjening de:Fernbedienung es:Mando a distancia fr:Télécommande he:שלט רחוק nl:Afstandsbediening ja:リモコン no:Fjernkontroll pl:Pilot zdalnego sterowania pt:Controlo remoto sq:Telekomanduesi fi:Kaukosäädin sv:Fjärrkontroll zh:遙控器

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