Patent ID: 8731727

Claim:
A method for controlling and testing a digital hydraulic controller having a feed line, a drain line, an output line and a plurality of individually switchable on/off valves which selectively connect the feed line to the output line or which connect the output line to the drain line, said method of controlling and testing comprising controlling steps of: detecting a controlled quantity in said output line; selecting at least one of the plurality of valves and switching it to control the amount of fluid passing through the selected at least one valve for controlling said controlled quantity to approach a target value, and periodically, and to improve control of the digital hydraulic controller, performing the testing steps of: performing a test sequence for calibration of individual valves of the plurality of individually switchable on/off valves in the digital hydraulic controller by: selecting a pair of valves including one valve which selectively connects the feed line to the output line, and one valve which selectively connects the output line to the drain line; opening said pair of valves; detecting a controlled quantity of a pressure or a flow rate of a fluid in said output line; calculating and setting in the controller calibration values for the individual valves of the pair of valves according to the detected controlled quantity of pressure or flow rate.