RUGGED LASER VIBRATION SENSOR FOR ON-BOARD VEHICLE TESTING

PRESENT VEHICLE DRIVE TRAIN DIAGNOSTICS USUALLY REQUIRE TEST STANDS AND OFTEN COMPONENT REMOVAL, MAKING THEM VERY INEFFICIENT. ON-BOARD VEHICLE TESTING CAN DRAMATICALLY INCREASE THE EFFICIENCY OF DIAGNOSITC DATA COLLECTION AND PROVIDE MORE REALISTIC, ON-LINE INFORMATION. THIS PROPOSAL DESCRIBES THE DEVELOPMENT OF A PORTABLE, NONCONTACT, RUGGED LASER DIODE VIBRATION SENSOR FOR ON-BOARD VEHICLE TESTING OF VEHICLE TRANSMISSIONS AND TRANSFER CASES. THE INSTRUMENT MEASURES VIBRATIONS FROM 1 HZ TO 100,000 HZ AND OUTPUTS ANALOG SIGNALS PROPORTIONAL TO THE VIBRATION VELOCITY AND ACCELERATION. THE WIDE FREQUENCY RANGE IS PARTICULARLY IMPORTANT IN IDENTIFYING BEARING FAULTS, WHICH SOMETIMES PRODUCE VIBRATION SPECTRA IN THE 50 KHZ TO 100 KHZ RANGE. ADAPTING SUCH AN INSTRUMENT FOR VEHICLE MOUNTING WILL ENABLE THE VIBROMETER TO MAKE "IN SITU" VIBRATION MEASUREMENTS TO DETERMINE THE GEARBOX CONDITION WITHOUT REMOVAL AND ALSO TO STUDY THE EFFECTS OF ROUGH ROADS ON THE GEARBOX.