Mechanical influences in sinusoidal force measurement

The paper describes mechanical influences which disturb a sinusoidal force calibration and hence have an influence on measurement uncertainty. The measurements are based on the application of a scanning vibrometer and the use of triaxial accelerometers. The measuring of many acceleration points on the top mass of the transducer makes it possible to obtain acceleration distributions from which a standard deviation can be derived; the triaxial accelerometer allows the observance of certain effects, like rocking modes, or other problems related to specific excitation frequencies of the force transducer. Both measurements can be related to each other. The rocking effects are discussed with FEM model calculations.