METHOD AND DEVICE FOR CALCULATING EXTERNAL FORCE APPLIED TO LOADING PART

PROBLEM TO BE SOLVED: To provide a method and a device for calculating an external force applied to a bucket, which enable accurate calculation of the external force applied to a loading part by a cargo for being loaded, without reference to a machine body size and a stationary or operating condition.SOLUTION: Kinetic equations associated with movable members are derived, respectively. Equations of motion associated with cylinders are derived by using the kinetic equations as expressions for work of the cylinders based on principles of virtual work, respectively. A cylinder generation force when an external force does not act on a bucket is calculated by solving the equation of motion on the basis of a detection value associated with each cylinder. The external force applied to the bucket is calculated on the basis of a difference between the cylinder generation force in the non-action of the external force and the actually measured cylinder generation force. 【課題】機体サイズ、および静止時あるいは動作時に拘らず、積載する荷により積載部に加わる外力を精度よく算出できるバケットの外力算出方法およびその装置を提供する。【解決手段】各可動部材についての動力学方程式をそれぞれ導出する。動力学方程式を仮想仕事の原理に基づく各シリンダの仕事の式に用いて各シリンダについての運動方程式をそれぞれ導出する。運動方程式を各シリンダに関する検出値に基づいて解くことでバケットに外力が作用しないときのシリンダ発生力を算出する。外力が作用しないときのシリンダ発生力と、実測のシリンダ発生力との差に基づいてバケットに加わる外力を算出する。【選択図】図１