sensors

okay
sensors are devices that measure a physical condition

passive part:

    they return an electrical value, eg. resistance, capacity, 
    voltage, current to the controlling circuit
    this produces analogue (continuous) values

active:

    they somehow 'compute' a value from reflection time, 
    a video image, ...
    this produces digital representations of analogue values

passive sensors for:

mechanical movement: potentiometers, physical pressure sensors, electromagnetic sensors
temperature: PTC/NTC
air pressure
light (visible & invisible/heat): resistive or current producing
sound (hearable and unhearable): microphones

there are sensors that are stationary and there are sensors you carry
on your body- you have to transmit the signal to the actor then
(use infrared or radio frquency for transmission)

there are sensors you have to activate or trigger on purpose:
pushbuttons, potentiometers, visible light sensors,

there are sensors which will detect your presence even if you dont want it:
they use invisible 'media' like infrared, ultrasonic, hidden cameras,
invisible lasers, switches you dont see, the capacitance of your body

see

(complete article)

a link page
the MIT 'responsive environments' group
the epanorame page on robotics
MIDI and Sensors

Link to this Page

enter. last edited on 21 February 2002 at 1:43 am by max2-171.dialin.uni-hamburg.de.