GAUGES FOR MEASURING DISPLACEMENTS FROM MILLIMETERS TO INCHES INCLUDING FREE FIELD DISPLACEMENT

THE PURPOSE OF THE PROPOSED EFFORT IS TO MODIFY AN EXISTING PAIDEVELOPED GAUGE SO THAT A) ITS OUTPUT SIGNALS ARE EASIER TO INTERPRET IN TERMS OF DISPLACEMENT, B) THE DISPLACEMENTS INFERRED ARE ACCURATE ENOUGH TO BE USED TO CORRECT BASELINE OFFSETS (E.G., OF ACCELEROMETERS), AND C) THE RANGE OF MEASURABLE DISPLACEMENT AMPLITUDES IS EXTENDED. THE GAUGE OPERATES BY MEASURING THE DISTANCE BETWEEN ITS HOUSING AND A FREE-FALLING OBJECT - AN "INERTIAL FRAME". INCOMPLETE CALIBRATION OF OUTPUT SIGNALS OVER THE RANGE OF DEPOSITION AVAILABLE TO THE FREE-FALLING OBJECT HAS MADE THE DEDUCTION OF DISPLACEMENT DIFFICULT AND UNCERTAIN. WE INTEND TO MODIFY THE GAUGE SO THAT ITS FULL CALIBRATION BECOMES A STRAIGHTFORWARD TASK, AND IMPROVE MECHANICAL AND ELECTRONIC SYSTEM ELEMENTS TO REDUCE MEASUREMENT ERROR FROM THOSE SOURCES.