Why not use traditional inductive sensors everywhere?
A clue is given by the types of industry sectors that use them most – military, aerospace, heavy industry, oil and gas. Typically in these sectors, performance and reliability are the primary selection factors, with cost being a secondary issue. These sectors are also technically sophisticated and the deployment of traditional inductive sensors requires some expertise because they need AC energisation and signal processing. Size and weight are important factors for many applications and most traditional inductive transducers are fairly bulky and heavy. For example, an LVDT to measure 100mm will be almost 300mm long at full stroke. On top of that is the space and cost required for the signal generation and processing circuitry. As a rule of thumb, for every £1 spent on the actual transducer, a further £1 will be needed for the signal processing. The net result is that traditional inductive transducers are often too expensive, too large or too heavy for many mainstream applications.
