Optical Sensors- optical sensor consists of an emitter and a detector. Depending on the arrangement between the emitter and the detector relative to each other, we can get two types of sensors, reflective sensors and break beam sensor.
Reflective sensors (the emitter and the detector are next to each other, separated by a barrier; objects are detected when the light is reflected off them and back into the detector)
Break-beam sensors (the emitter and the detector face each other; objects are detected if they interrupt the beam of light between the emitter and the detector)
The emitter is made of LED whereas the detector is usually aphotdiode
Light Reflective Sensor- light reflectivity depends on the colour of the surface
Light reflective sensors are used for object presence detection, object distance detection,surface feature detection (finding/following markers/tape),wall/boundary tracking,rotational shaft encoding (using encoder wheels with ridges or black and white colour),bar code decoding
Infrared Sensors- infrared sensors function in the infra red part of the frequency spectrum. Being an active sensor they consist of a receiver and an emitter. IR is preferable to visible light in robotics applications because it suffers a bit less from ambient interference, it is not visible and simply because it can be easily modulated
Beam Brake Sensor- Any pair of emitter and detector device can be used to produce such a sensor
LDR(Light Dependent Resistor)- light dependent resistor is a resistor whose resistance decreases with increasing incident light intensity. It can also be referred to as a photoconductor.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment