When talking aerospace sensors, ‘analogue’ or ‘digital’ become hardly necessary, being simply a matter of method of operation, and that it is the underlying physical principles which are all-important.
Classification of sensors – In discussing Torque Sensor one has to decide if you should classify them in accordance with the physical property they utilize (like piezoelectric, photovoltaic, etc.) or in accordance with the function they perform (like measurement of length, temperature, etc.). Within the former case one can present a reasonably integrated take a look at the sensing process, yet it is a little disconcerting when one wishes to compare the merits of, say, two kinds of temperature sensors, if one must look over separate sections on resistive, thermoelectric and semiconductor devices to help make the comparison.
Alternatively, to attempt to differentiate devices by function often tends to be an extremely boring catalogue of numerous unrelated devices. What is important about them is signals are transformed from a single form to another. Additionally it is easy to discuss sensors from your functional viewpoint, under headings like length, temperature, etc., ideal for somebody that actually would like to select or use a sensor for the application rather than just read around the subject.
The words ‘sensors’ and ‘transducers’ are both popular within the description of measurement systems. The former is popular in the united states whereas the latter is much more often found in Europe. Deciding on a words in science is rather important. In recent years we have seen a propensity to coin new words or even to misuse (or misspell) existing words, and this may lead to considerable ambiguity and misunderstanding, and is likely to diminish the preciseness from the language. The issue has become very apparent in the computer and microprocessor areas, where preciseness is particularly important, and can seriously confuse persons entering the topic.
The term ‘sensor’ is derived from sentire, meaning ‘to perceive’ and Compression Load Cell is from transducere meaning ‘to lead across’. A dictionary definition Chambers 20th Century) of ‘sensor’ is ‘a device that detects a big difference in a physical stimulus and turns it right into a signal which is often measured or recorded’; a corresponding definition of ‘transducer’ is ‘a device that transfers power from a single system to a different inside the same or in different form’.
A sensible distinction is to use ‘sensor’ for your sensing element itself, and ‘transducer’ for that sensing element plus any associated circuitry. For example, thermistors are sensors, because they respond to a stimulus (changes its resistance with temperature), only become transducers when connected in a bridge circuit to transform alternation in resistance to alternation in voltage, since the complete circuit then transduces through the thermal towards the electrical domain. A solar cell is both a sensor and a transducer, as it responds to some stimulus (generates a current or voltage in reaction to radiation) as well as transducer through the radiant to the electrical domain. It will not require any associated circuitry, though in practice an amplifier would usually be used. All transducers thus have a sensor, and lots of (though not every) sensors can also be transducers.
The difference is pretty small, and the moment one actually utilizes a sensor (by applying power to it) it might be 3 Axis Load Cell. An appealing classification of devices can be achieved by considering the oygoqj forms of energy or signal transfer.
The term ‘actuate’ means ‘to put into, or incite to, action’ and actuators are devices that make the display or observable output in a measurement system for instance a light-emitting diode (LED) or moving coil meter. They may be obviously transducers utilized for output purposes, since they transduce from one domain to another (ie. electrical to radiant for LEDs).