Computer Interfacing

Transducers

those that take some physical quantity and derive an

equivalent electrical signal from it.

It is worth considering some examples of physical quan-

tities we might wish to convert in this way, and consider

how such conversion might be carried out. Their rel-

evance to computer control is also worth investigation.

Examples of such physical quantities are: heat, light,

weight, force, linear displacement, angular displacement,

stress in mechanical structures, and fluid velocity.

Transducers for all of these quantities exist and may be

classified as being either active or passive types. To make

the distinction clear, an active transduce ...