When talking torque sensor, ‘analogue’ or ‘digital’ become hardly essential, being simply a matter of approach to operation, and that it must be the actual physical principles that are all-important.
Classification of sensors
In discussing sensing devices one has to decide if you should classify them according to the physical property they use (like piezoelectric, photovoltaic, etc.) or in accordance with the function they perform (like measurement of length, temperature, etc.). Inside the former case anybody can present a reasonably integrated look at the sensing process, yet it is a little disconcerting when one desires to compare the merits of, say, 2 kinds of temperature sensors, if one has to look through separate sections on resistive, thermoelectric and semiconductor devices to help make the comparison.
Alternatively, to try to differentiate devices by function often is commonly a rather boring catalogue of numerous unrelated devices. The main thing on them is signals are transformed from one form to another. It is additionally easy to discuss miniature load cell from the functional viewpoint, under headings such as length, temperature, etc., ideal for somebody that actually would like to select or make use of a sensor for the application as opposed to just read across the subject.
The words ‘sensors’ and ‘transducers’ both are widely used in the description of measurement systems. The previous is popular in the united states whereas the second is much more often used in Europe. The option of words in science is rather important. In recent years there has been an inclination to coin new words or to misuse (or misspell) existing words, and this might lead to considerable ambiguity and misunderstanding, and tends to diminish the preciseness in the language. The challenge has been very apparent within the computer and microprocessor areas, where preciseness is especially important, and can seriously confuse persons entering the niche.
The phrase ‘sensor’ is derived from sentire, meaning ‘to perceive’ and ‘transducer’ is from transducere meaning ‘to lead across’. A dictionary definition Chambers Twentieth Century) of ‘sensor’ is ‘a device that detects a change in a physical stimulus and turns it in to a signal which can be measured or recorded’; a corresponding definition of ‘transducer’ is ‘a device that transfers power in one system to a different in the same or even in different form’.
A sensible distinction is to apply ‘sensor’ for your sensing element itself, and ‘transducer’ for the sensing element plus any associated circuitry. For instance, thermistors are sensors, given that they react to a stimulus (changes its resistance with temperature), only become transducers when connected in a bridge circuit to convert alternation in potential to deal with alternation in voltage, because the complete circuit then transduces from your thermal towards the electrical domain. A solar cell is both a sensor and a transducer, as it responds to your stimulus (generates a current or voltage responding to radiation) and also transducer from the radiant towards the electrical domain. It does not require any associated circuitry, though in practice an amplifier would usually be utilized. All transducers thus hkjrzk a sensor, and several (though its not all) sensors will also be transducers.
The difference is quite small and the moment one actually uses a sensor (by applying capacity to it) it might be load sensor. An appealing classification of devices can be accomplished by thinking about the various forms of energy or signal transfer.
The term ‘actuate’ means ‘to placed 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. These are needless to say transducers employed for output purposes, because they transduce from a single domain to another one (ie. electrical to radiant for LEDs).