Introduction
A proximity sensor detects the presence of an object within a set distance. Robots use them for near field work, such as grasping an object or avoiding it. They are a type of external state sensor in Robotic Sensors.
How it works
flowchart LR A["Presence of object"] --> B["Change in a<br/>physical property"] B --> C["Output as an<br/>electrical signal"]
The physical property depends on the type of sensor, for example inductance, capacitance, reflected light or sound.