Sensors are used in many systems including security, temperature control, motion and eye tracking. They are also used in games controllers and to help scientists research medical conditions.

Motion sensors send a beam of light out and can detect if the beam is broken. They may also use radio or sound waves, which will be reflected back if they are interrupted. However, most security systems use passive sensors. These don't send signals out, but wait to receive a signal in. The most commonly used passive sensor is an infra-red sensor. Since all human beings emit infra-red energy, as soon as a person walks within reach of an infra-red sensor they will be detected.

Leap Motion

Examples of the use of motion sensor technology include:

  • The Leap Motion is a motion sensor that plugs into a computer through a USB connection, allowing the user to control the device without actually touching it. It replaces the need for a mouse and keyboard and could also be used to control a TV.
  • The Wiimote - which came with the original Nintendo Wii. This was the first games console to make a motion sensor the principal controller.
  • The Kinect - designed for use with Microsoft's Xbox but it can also be used with other computers. It detects objects in 3D and can 'sense' movement. The Kinect is also being used for medical research and can detect a person's heart rate.

Cecily Morrison is researching how doctors can use the Microsoft Kinect