USC Mechanical Engineering LAMSS Laboratory for Adaptive Materials and Smart Structures USC Mechanical Engineering Outline Mechatronics – Micro-controllers Education Vibration Monitoring Enhancement Program (VMEP) E/M Impedance Structural Health Monitoring Wave Propagation Non-destructive Evaluation Smart Materials Actuation USC Mechanical Engineering EMCH 367 - Controllers Motorola MC68HC11EVB: $200 - Ideal for still applications - More memory suits bigger programs - Communicates directly with PC Same chip: MC68HC11 Homebuilt: $20 + labor - Cheaper - Smaller - Better suited for autonomous robots USC Mechanical Engineering EMCH 367 Projects Robert Legg Dave Durgin In memory of Dale Earnhardt 1951-2001 USC Raceway USC Mechanical Engineering EMCH 367 Projects Guided Autonomous Vehicle David Butts Thomas Tisdale USC Mechanical Engineering Projects – Summer 2000 CD-Bot : Searching light and avoiding objects Peter James USC Mechanical Engineering Projects – Summer 2000 CD-Bot : IR detection Peter James USC Mechanical Engineering Outline Mechatronics – Micro-controllers Education Vibration Monitoring Enhancement Program (VMEP) E/M Impedance Structural Health Monitoring Wave Propagation Non-destructive Evaluation Smart Materials Actuation VMEP Roadmap US ARMY USC Mechanical Engineering NC, KY, MS-ARNG SC-ARNG AASF UH-60 VMEP/VMU SYSTEM PROTOTYPE BETA TESTING AT SCARNG AH-64 Raw Data Crew Chief’s Laptop USC Data Repository Condition Crew Chief’s Indicators Laptop VPROCs AMPs RT&B and HUMS CI’s Parts and Maintenance ULLS-A O&S Cost Benefit Analysis RT&B Vibration Management VPROCs AMPs HUMS Vibration Monitoring Diagnostics and Prognostics R&R VMU/VMEP Integrity VMEP data must be: • Catalogued • Time/aircraft synchronized • Accessible and retrievable VMU 1-- 50 USC Mechanical Engineering SCARNG Vibration Management Enhancement Program (VMEP) A partnership has been established to conduct enhanced implementation of the VMEP project and experimentally identify life-cycle cost savings and benefits. USC Mechanical Engineering AVA System © 2000 by SC-ARNG USC Mechanical Engineering AVA RT&B Procedure Initial vibration patterns at various speeds Vibration reduction after RT&B correction © 2000 by SC-ARNG USC Mechanical Engineering VMEP Hardware-Software Smart Rotor Smoothing Algorithms Gear and Drive Train Monitoring Vibration Management Unit (VMU) Engine Vibration Health Monitoring Light-weight low-cost data acquisition and processing unit (COTS components), with easily upgradeable open architecture hardware and software © 2000 by SC-ARNG VMEP RT&B Tests 1.5 VERT Magnitude LAT Magnitude Vibration, IPS 5/18/1999 Vibration, IPS USC Mechanical Engineering 1.5 5/19/1999 1.0 5/20/1999 0.5 5/18/1999 1 5/19/1999 5/20/1999 0.5 0 0.0 0 20 40 60 80 100 Flight speed, kt 120 140 0 20 RT&B adjustments Date and time Main Rotor Adjustments Weight Blade 2 05/18/99; 14:48 Tab 6-10 Blade 1 Tab 6-10 Blade 4 Pitch Link Blade 3 Pitch Link Blade 4 05/19/99; 08:54 Tab 8-10 Blade 3 Tab 8-10 Blade 4 40 60 80 100 Flight speed, kt +100 grams +2.0 deg +2.5 deg +0.5 flats -1.25 flats +1.5 deg -1.0 deg 120 140 USC Mechanical Engineering USC-VMEP Data Repository ULLS-A (tapes) Engineering & Info. Tech. MATLAB (www) Data Repository Math Statistics Teradata computer RITA-HUMS (www) Bio Statistics AVA (Kermit) AH-64 Drive-train Vibration Survey USC Mechanical Engineering Tail Rotor Gearbox Hanger Bearing Nose Gearbox Main Transmission Input and Accessory T700 Engine Intermediate Gearbox USC Mechanical Engineering Outline Mechatronics – Micro-controllers Education Vibration Monitoring Enhancement Program (VMEP) E/M Impedance Structural Health Monitoring Wave Propagation Non-destructive Evaluation Smart Materials Actuation Health Monitoring of Aging Aircraft Structures USC Mechanical Engineering #1 -- Trailing edge disbond gauge #3 -- Main spar disbond gauge AGING! Local-area health monitoring of a helicopter rotor blade. Giurgiutiu, et al (1997) Damage due to aging Aging aircraft panel with simulated crack Active piezoelectric sensors on an engine blade Z str ( ) Z ( ) = iC 1 312 Z PZT ( ) + Z str ( ) 175 Data-acquisition and processing computer 1 Impedance C hanges for Lap Joint 3 150 No Bolt B olt 125 Re (Z) (Ohms) HP 4194A Impedance Analyzer B olt + Washer 100 75 50 25 Signal multiplexer Health-monitored structure instrumented with wafer transducers 0 0 100 200 300 400 500 Frequency (kHz) 600 700 800 RMS Impedance Change Comparisons for M-Bond 200 Adhesive RMS Impedance Change USC Mechanical Engineering E/M Impedance Method 160% 140% 120% 100% 80% 60% 40% 20% 0% Lap Joint 1 Lap Joint 2 Lap Joint 3 Lap Joint 4 Bolt, Nut, Washer Bolt + Nut Free Results by Giurgiutiu, Turner, 1998 USC Mechanical Engineering Outline Mechatronics – Micro-controllers Education Vibration Monitoring Enhancement Program (VMEP) E/M Impedance Structural Health Monitoring Wave Propagation Non-destructive Evaluation Smart Materials Actuation Waves in solid were studied Waveform visualization Wave speed dispersion Lamb wave – symmetric mode Lamb waves and flexure wave velocities dispersion 6.000 Lamb wave S0 mode(d=0.5mm) Lamb wave – anti-symmetric mode 5.000 Flexure wave Velocity (mm/micro-s) USC Mechanical Engineering Wave Propagation Theories Study 4.000 Lamb wave S0 mode(d=0.8mm) 3.000 2.000 Lamb wave A0 mode(d=0.5mm) Lamb wave A0 mode(d=0.8mm) 1.000 0.000 0 500 1000 1500 2000 2500 3000 Freqency (kHz) 3500 4000 4500 5000 Embedded piezoelectric active sensor development 10 kHz: COL 0 10_A1 Excite at position A1 In ex COL B ex COL 1 COL 7 C ex D ex COL 1 3 E ex COL 1 9 4 .5 5 4 0 .9 1 PZT wafer transducers on beam specimen Wave propagation experiment at different frequencies Wave speed – Frequency curve 8 6 .3 6 1 3 1 .8 2 In B 1 0 0 1 7 7 .2 7 C 2 0 0 D 3 0 0 E 4 0 0 2 2 2 .7 3 2 6 8 .1 8 3 1 3 .6 4 3 5 9 .0 9 4 0 4 .5 5 45 0 0 .5 0 .3 0 .1 0 .1 0 .3 0 .5 0 .7 0 .9 1 .1 1 .3 1 .5 1 .7 1 .9 2 .1 2 .3 2 .5 2 .7 2 .9 3 .1 3 .3 3 .5 3 .7 3 .9 4 .1 4 .3 4 .5 time CO L 7 8 100 k Hz: 100_A1 Ex c ite at posit ion A1 In ex C OL E ex C OL 1 B ex C OL 7 9 C ex C OL 8 5 D ex C OL 9 1 100 0 100 200 300 6.000 In B 2 0 0 C 4 0 0 4 0 0 D 6 0 0 E 8 0 0 5.000 500 600 4.000 700 3.000 800 y 2.000 900 Axial 0 0 .0 5 0 .1 0 .1 5 0 .2 0 .2 5 0 .3 0 .3 5 0 .4 0 .4 5 0 .5 0 .5 5 0 .6 0 .6 5 0 .7 0 .7 5 0 .8 0 .8 5 0 .9 0 .9 5 1 1 .0 5 1 .1 1 .1 5 1 .2 1 .2 5 1 .3 1 .3 5 1 .4 1 .4 5 1 .5 time Flexure A 1.000 B C D E x 0.000 0 500 1000 1500 2000 2500 Frequency (kHz) 3000 3500 4000 4500 14mm Wave speed (mm/s) USC Mechanical Engineering 50 914mm USC Mechanical Engineering Experiment on aircraft panels Tektronix TDS 210 digital oscilloscope R7 Data acquisition laptop PC with PCMCIA GPIB card Aging aircraft panel with PZT active sensors HP 33120A signal generator R6 10-mm EDM crack R5 Trek 50/750 HV amplifier Transmitter R1 R2 R3 R4 T R1 R2 R3 R4 R5 R6 R7 -250 0 250 500 750 1000 1250 Time, micro-sec 1500 1750 2000 2250 2500 PZT wafer transducers array on aircraft panel Wave analysis USC Mechanical Engineering Development of Concepts for Automatic Health Monitoring System The future of such sensing is conceptualized as integrated part of real structures and could be compared with nervous systems of living organisms, so that the active sensors will “feel” the structure and provide a feedback in terms of information on the structural health. Sensors Cluster 3 Sensors Cluster 2 Data concentrator Data concentrator Central Health monitoring PC Sensors Cluster 1 Wireless health monitoring system on board of civil aircraft Sensors Cluster 4 USC Mechanical Engineering Outline Mechatronics – Micro-controllers Education Vibration Monitoring Enhancement Program (VMEP) E/M Impedance Structural Health Monitoring Wave Propagation Non-destructive Evaluation Smart Materials Actuation Smart Materials USC Mechanical Engineering Applied field Upon the application of an external field, the material expands or contracts. Smart material Smart (active, intelligent, adaptive) materials: - piezoelectric materials electric field - magnetostrictive materials magnetic field - shape memory alloys temperature Applications:- space technology - rotorcraft and aircraft industry - sonar technology - vibration and noise reduction Characterization of the PiezoSystems Jena PAHL120/20 piezoelectric actuator 20 Volts 40 Volts 60 Volts 80 Volts 105 Volts 120 Volts 140 Volts 150 Volts 3000 2500 Force (N) USC Mechanical Engineering 3500 2000 1500 External stiffness 1000 500 0 20 40 60 80 100 120 Displacement (m) Manufacturer: PiezoSystems Jena Model # : PAHL120/20 Maximum voltage (V): 150 Max. displ. (m): 120 Blocked force (N): 3500 Capacitance (F): 42 Coupled electro-mechanical behavior of PAHL 120/20 Actuator ke ki Force, Displacement Voltage Etrema actuator R UT RE LE ULE UR URE Measured : UT, UR, delay (phase) between and fUT 10001050 U 2000 R 100 Manufacturer: Etrema Inc. Model # : AA –140J013 Maximum current (A RMS): 3 Max. displ. (m): 70 Max. dynamic force (N): 890 Blocked force (N): 1740 DC Resistance (W): 2.3 Inductance (mH): 3.5 Impedance (Ohms) USC Mechanical Engineering Impedance measurements on the ETREMA AA140J130 Magnetostrictive actuator Impedance analyzer ~0V PhAngle method 23.0V PhAngle method 34.5V PhAngle method 46.4V PhAngle method 58.6V 80 60 40 20 1000 1200 1400 1600 1800 2000 Frequency (Hz) Electric impedance change with current and frequency USC Mechanical Engineering Summary Mechatronics – Micro-controllers Education Vibration Monitoring Enhancement Program (VMEP) E/M Impedance Structural Health Monitoring Wave Propagation Non-destructive Evaluation Smart Materials Actuation