Applications for linear feedback sensors are numerous and varied. Likewise, linear feedback sensors are available in numerous form factors and with a wide variety of performance characteristics. Matching your application to the most appropriate sensor can be a daunting proposition.
When choosing the right linear feedback sensor, it is helpful to first define the job the sensor is being tasked to do. One way to do this is to think in terms of the three M’s: (M)easuring, (M)onitoring, and (M)otion control. Linear feedback sensor characteristics that are critical for one of these jobs may not matter as much for another job. We’re going to take a look at each of these jobs and discuss some of the more important linear feedback selection criteria associated with each.
Measuring: In measuring applications, the linear feedback sensor is asked to perform the job of an “electronic ruler”. That is, the sensor is a measuring device used to gauge the size (length, width, thickness, etc.) of the part being produced or processed. Examples of measuring applications include cut-off saws, or any other cut-length applications. In such applications, it is absolutely critical for the feedback sensor to provide 1) high accuracy (low non-linearity), and 2) fine resolution. Other factors, such as a fast update rates and highly rugged enclosures are typically not as important in most measuring applications.