Abstract: A method and apparatus for measuring the mass of a dynamic load without being influenced by vibration caused by the apparatus itself or the environment. A dynamic load sensor that supports the dynamic load is periodically and continuously reciprocated in at least one predetermined direction. Within the dynamic load sensor, one end of a member comprising a spring system is fixed to a base of a non-spring system, the other end of the spring system is free. A load is applied to the free end of the spring system. The base is continuously and periodically agitated along with the spring system. A displacement of the base y.sub.1 and a displacement y.sub.2 of the free end of the spring mass system are continuously measured. By obtaining the first-order derivatives y.sub.1 and y.sub.2 and the second-order derivatives y.sub.1 and y.sub.2 from said displacements y, and y.sub.2 with respect to time, the mass of the load, m, can be calculated by the equation:m?y!=mg-?(mg+kf.sub.2 (y-y.sub.1 +y.sub.2))-f.sub.3 (y-y.sub.

Abstract: A method and apparatus for measuring a load under a dynamic state where variations such as swinging and vibration exist. One of the ends of a member constituting a spring system is fixed with the other end free. A stationary load We is calculated in accordance with equation ##EQU1## by attaching a load to the free end and measuring the instantaneous displacement Yi. In the above equation, Wi is the instantaneous load, g is gravitational acceleration, g.sub.(A/L)i is the acceleration of the free end obtained by differentiating twice the displacement Yi, and k is a spring constant. When a base to which the member constituting the spring system is fixed undergoes variations such as swinging and vibration the stationary load We is determined by ##EQU2## where g.sub.(G/L)i is the acceleration of variation of the base.