Electro hydraulic flow control valves, either proportional or servo (EHSV), are used in industry in a wide number of applications like machine tools, testing equipment, mining machinery, fatigue testing, flight simulation, paper machines, ships and electromagnetic marine engineering, injection molding machines, robotics, steel and aluminum mill equipment and autonomous manufacturing systems. These systems have favorable size to power ratio, precise and accurate control, and ability to apply very large forces. Servo hydraulic systems offer several other benefits over their electrical counter parts. For example, hydraulic systems are mechanically "stiffer", resulting in higher machine frame resonant frequencies for a given power level, higher loop gain and improved dynamic performance.