For the prevention of vibration exposure of human hand-arm-systems by separation of man and machine it is necessary to provide a practical reasonable characteristic function for mechanical modelling of hand-arm-systems. At present the impedance of one hand-arm-system measured under laboratory conditions acc. DIN 45677 (ISO 10008) is used as target function. In usecases with tow hands this impedance will be duplicated. This method reflects the practical use of handheld machinery only faultily. Therefore it is necessary to carry out impedance measurements under practical conditions in the laboratory with both hands. This overall impedance is the precondition mechanical modelling e.g. in test stands for handheld machinery.
For wide application the measured impedance values shall be statistically secured and prepared for standardization. Subsequently the hand-arm-models of project F 1512 will be revised and the hand-arm test stand of the Federal Institute of Occupational Safety and Health will represent the state of the art.
Unit 2.4 "Workplaces, Safety of Machinery, Operational Safety"