US Patent 7114430 Adaptive position determining system for hydraulic cylinder

A position determining system may include a hydraulic cylinder and a flow control device operatively connected to the hydraulic cylinder. A controller may be configured to supply an actuating signal to the flow control device. The controller may be configured to monitor a characteristic associated with the actuating signal, determine a hydraulic fluid flow rate in the hydraulic cylinder based on stored information relating the hydraulic fluid flow rate to the characteristic associated with the actuating signal, calculate a position of a component associated with the hydraulic cylinder based on the hydraulic fluid flow rate, and update the stored information when the determined position deviates from an actual position of the component.