REMOTE CONTROL

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

The term remote control can be also referred to as "remote" or "controller" when abbreviated. It is known by many other names as well, such as the "clicker", "channel-changer", "splat", "magic hand", etc. Commonly, remote controls are used to issue commands from a distance to televisions or other consumer electronics such as stereo systems and DVD players. Remote controls for these devices are usually small wireless 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 AA size batteries.

TECHNIQUE

Most control remotes for electronic appliances use a near infrared diode to emit a beam of light that reaches the device. A 940 nm wavelength LED is typical. This infrared light is invisible to the human eye but carries signals that are detected by the appliance, as well as by the sensor of a digital camera.

With a single channel (single-function, one-button) remote control the presence of a carrier signal can be used to trigger a function. For multi-channel (normal multi-function) 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 frequ

ency filters are applied to separate the respective signals. Nowadays digital procedures are more commonly used. One can often hear the signals being modulated on the infrared carrier by operating a remote control in very close proximity to an AM radio not tuned to a station.

USAGE

Industry

Remote control is used for controlling substations, pump storage power stations an

d HVDC-plants. For these systems often PLC-systems working in the longwave range are used.

Emergency

Remotely controlled machinery is used in radioactive or toxic environments to avoid human casualties and to prevent damage to human health. For example, remotely controlled robots were used during liquidation of circumstances of Chernobyl disaster.

Military

In World War I the Imperial German Navy employed FL-boats (Fernlenkbootes) against coastal shipping. These were driven by internal combustion engines, and controlled remotely from a shore station through several miles of wire wound on a spool on the boat. An aircraft was used to signal directions to the shore station. EMBs carried a high explosive charge in the bow and traveled at speeds of thirty knots.^[7]

The Soviet Red Army used remotely controlled teletanks during 1930s in the Winter War against Finland and the early stages of the Great Patriotic War. A teletank is controlled by radio from a control tank at a distance of 500–1,500 meters, the two constituting a telemechanical group. The Red Army fielded at least two teletank battalions at the beginning of the Great Patriotic War. There were also remotely controlled cutters and experimental remotely controlled planes in the Red Army.

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.

Video games

Video game consoles had not used wireless controllers until recently, mainly because of the difficulty involved in playing the game while keeping the infrared transmitter pointed at the console. Early wireless controlers were cumbersome and when powered on alkaline batteries, lasted only a few hours before they needed replacement. Some wireless controllers were produced by third parties, in most cases using a radio link instead of infrared. Even these were very inconsistent, and in some cases, had transmission delays, making them virtually useless. The first official wireless controller made by a first party manufacturer was the WaveBird for Nintendo Gamecube. The Wavebird changed the face of wireless technology in video game consoles. In the current generation of gaming consoles, wireless controllers have become the standard.

Toys

Main article: Radio-controlled model

Remote control toys, such as racing cars, boats and even aircraft are a favorite pastime of many people.

Contributed by : Nik Noor Diana Mohd Noor (2007239692)