Robotic sensors
Robotic sensors are used to estimate a robot's condition and environment. These signals are passed to a controller to enable appropriate behavior.
Sensors in robots are based on the functions of human sensory organs. Robots require extensive information about their environment in order to function effectively.
Classification
Sensors provide analogs to human senses and can monitor other phenomena for which humans lack explicit sensors.- Simple Touch: Sensing an object's presence or absence.
- Complex Touch: Sensing an object's size, shape and/or hardness.
- Simple Force: Measuring force along a single axis.
- Complex Force: Measuring force along multiple axes.
- Simple Vision: Detecting edges, holes and corners.
- Complex Vision: Recognizing objects.
- Proximity: Non-contact detection of an object.
They can measure:
- Object Proximity: The presence/absence of an object, bearing, color, distance between objects.
- Physical orientation. The co-ordinates of object in space.
- Heat: The wavelength of infrared or ultra violet rays, temperature, magnitude, direction.
- Chemicals: The presence, identity, and concentration of chemicals or reactants
- Sound: The presence, frequency, and intensity of sound.
Internal sensor*
It is the part of the robot. Internal sensors measure the robot's internal state. They are used to measure position, velocity and acceleration of the robot joint or end effectors.Position sensor
Position sensors measure the position of a joint. They include:- Encoder: a digital optical device that converts motion into a sequence of digital pulses.
- Potentiometer: a variable resistance device that expresses linear or angular displacements in terms of voltage.
- Linear variable differential transformer: a displacement transducer that provides high accuracy. It generates an AC signal whose magnitude is a function of the displacement of a moving core.
- Synchros and Resolvers