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Correcting errors that never happen

The Luenberg Observer lets motion-control systems mathematically predict and cancel position errors before they happen. For many years the standard means of controlling servoloops on motion controllers (or other devices) has been the PID loop. Back in the days of analog control the motion controller was typically a CNC device responsible for closing the proportional-gain (P) loop and, if used, the steady-state or integral gain ( I ) loop. A tachometer (tach) or speed loop was used in lieu of a derivative-gain (D) function. The closed position and speed loops configured by this type of cascaded control were common. As processor technology advanced, it became routine for the motion controller to close all servoloops. This was based on the assumption that the fastest and most
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Flow Controllers
Flow controllers monitor and maintain flow-rate variables, typically in process applications.
Brake Controllers
Brake controllers are used to control braking systems. They can simply engage and disengage the brake, or control the speed of engagement, breakaway torque, and other variables.
Web Controllers
Web controllers maintain control functionality over processes with web or sheet rollers.  Control functionality includes maintaining tension of the web, centering on the track, and material feed rates.
Pressure Controllers
Pressure controllers accept input from pressure sensors, transmitters, gauges, and other devices and subsequently control adjustment to the pressure to maintain or achieve the desired pressure level.
pH Controllers
pH and ORP controllers monitor and can control the pH (acidity or alkalinity) and/or the ORP (oxidation reduction potential) of liquids involved in a testing or process application.
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Topics of Interest

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