Method and device for controlling work machine

Abstract

An electro-hydraulic transducing valve ( ) and other elements associated with cylinder-controlling components, such as a control valve ( ), are connected to the output end of a controller ( ) adapted to perform control computation based on electric manipulation signals send from and electric joy stick ( ) or the like. Control valve return pressure (P ) and load-sensing pressure (P ) are detected by the first and second detectors ( ), ( ) so that start-up of a hydraulic cylinder ( ) or the like is detected based on rise of the differential pressure (&Dgr;P) between the two types of pressures. The controller ( ) is provided with a function generating unit ( ) and a calibration computing unit ( ). The function generating unit ( ) has a reference function (F) that determines the relationship between electric manipulation signals and command values for commanding the electro-hydraulic transducing valve ( ) and other similar elements. The calibration computing unit ( ) is adapted to correct the reference function (F) by computing the calibration deviation (&Dgr;S) between the actual command value stored at the moment with the cylinder actually started and the provisional command value that corresponds to an imaginary start-up moment of the cylinder and has been set beforehand according to the reference function (F), and adding the calibration (&Dgr;S) to the reference function (F).