Electric and Magnetic Sensors and Actuators
The class of electric and magnetic sensors and actuators is the broadest by far of all other classes, both in numbers and types and the variety within each type. Perhaps this should come as no surprise since in a majority of cases a sensor exploits the electrical properties of materials and, with few exceptions, the requisite output is electrical. In fact, we could argue that even sensors that were not placed in this category belong here as well. Thermocouples exploit electrical effects in conductors and semiconductors - an electrical phenomenon. Optical sensors are either based on wave propagation, which is an electromagnetic phenomenon, or on quanta, which are measured through electronic interaction with the atomic structure of the sensor. It would take little to argue that this is an electric phenomenon. In terms of actuation, most actuators are either electrical or, more commonly, magnetic. This is particularly true of actuators that need to provide considerable power. However, for the sake of simplicity and to follow the basic idea of limiting the number of principles involved in each class of sensors, we will limit ourselves here to the following types of sensors and actuators.
Electric and Magnetic Sensors and Actuators, Page 1 of 2
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