Radar 

Radar stands for Radio Detection And Ranging or Radio Angle Detection And Ranging. It is a system used to detect, range (determine the distance of) and map objects such as aircraft and rain. The advantage of the radar sensor is that it can be used for both long and short-range distances with different frequencies. 76-78 GHz frequency is used for a long-range and 24.125 GHz for short-range distances.

Lidar

LIDAR stands for Light Detection and Ranging, or Laser Imaging Detection and Ranging. It is a technology which is used to determine the distance to an object or surface using laser pulses. Similar to radar technology, which uses radio waves instead of light, Lidar determines the distance to an object by measuring the time delay between transmission of a pulse and detection of the reflected signal. It is used for measuring vehicle speed measurement.

Infrared

The infrared (IR) camera consists of several components. It is important to distinguish two different versions of the IR camera: Near InfraRed (NIR) and Far InfraRed (FIR). In both systems, a camera is used which is sensitive to heat radiation of objects.

Vision (Camera)

A vision sensor is a device which collects light on a light-sensitive back-plate. This back-plate can have different properties and purposes. When the IR camera vision sensors installed with only one sensor, then it is called a mono setup. However, when two or more sensors are used, it is called a stereo setup.

Ultrasonic

Ultrasonic sensors are currently widely used in the automotive industry for short distance obstacle detection. It can assist the driver for reverse manoeuvres. Based on a 40 kHz sound pressure wavelength, the sensor covers a range of 1 to 3 metres detecting objects in a horizontal beam with a width of maximum 100° and 60° vertical.