Light+Movement+Sensor

=__Light Movement Sensors__=

Some common applications of the light movement sensors include: anti-theft devices, man-down alarms to detect non motion, smart appliances to turn off power when not in use. __Greenhouses:__are another way that light movement sensors are used is in Greenhouses the computer controls the temperature in a greenhouse to maintain the conditions required for the plants in it to grow. If the temperature gets too cold then the computer turns on a heater to keep the plants warm.

__Traffic light system__: The computer controls the sequences of lights displayed at a cross-roads to ensure that cars do not crash Additionally the computer operates a pedestrian crossing to let pedestrians cross the road when a button is pressed.

__Robot Arm__: The computer controls the movement of a robot arm which sprays parts of a car body. The arm must only spray when the body part is present and must then follow a programmed spraying path. The arm must stop if any foreign object, such as a human being, gets in its way.

Devices are controlled by an electrical signal and used to provide output. Examples include motors, buzzers, pumps and light bulbs. The action that these devices take will depend on the strength of the analogue voltage sent to them. e.g. A bulb is off if it receives no voltage and gets brighter as the voltage increases.