Abstract: Combination is disclosed for deriving and displaying the full complement of nine dynamic parameters associated with a mechanical motion transmission system; the parameters comprise: (1) angular displacement, (2) angular velocity, (3) angular acceleration, (4) moment of force (i.e. torque), (5) kinetic energy, (6) work, (7) power, (8) momentum and (9) impulse. Quasi-instantaneous, absolute measurements are derived from elapsed-time measurements between successive sensing of fixed, equal, position events such as electric pulses generated by an incremental shaft encoder. The parameters are displayed on the X and Y axes of a Cartesian or other suitable graph where the X-axis (i.e. the independent axis) indicates the angular displacement of the encoder expressed as a succession of fixed, equal position events in the units of radians. The Y-axis (i.e. the dependent axis) indicates the absolute value of the parameters.

Abstract: A speed measuring device is provided for use as a diagnostic tool to analyze the sub-cyclic dynamic performance and to monitor the condition of moving elements within a mechanical or electromechanical system. Substantially instantaneous, absolute speed measurements are derived from elapsed time measurements between successive sensing of fixed, equal, position events such as generated by incremental position pulses of a shaft position encoder; said encoder being attached to one of the moving elements within the said system. An assessment of the dynamic performance and condition of the system is ascertained by comparing the speed profile with previous speed profiles obtained during normal system operation. Comparative differences in the said profiles provide an indication of changes of the driving and friction forces within the system which, in turn, can provide an indication of faulty elements.