30 July 2014 Gwo-Sheng Peng (on behalf of Mr. Jiun-Kai Chen) Center for Measurement Standards/ Industrial Technology Research Institute Tel: UNIQUE TYPE OF PRIMARY HIGH SHOCK CALIBRATION SYSTEM USING ELECTROMAGNETIC EXCITER

Copyright 2014 ITRI 工業技術研究院 Outline 1. Motivation 2. Calibration methods 3. Measurement setup 4. Preliminary results 5. Conclusions

Copyright 2014 ITRI 工業技術研究院 Motivation: additional requests from industry m/s 2 NML Low shock : 200~ m/s 2 500~5 000 m/s ~ m/s 2 Electric component 100~200 m/s 2 Laptop Electric connector 500~ m/s 2 3C 、 Cellphone 、 GPS 500~1 000 m/s 2 Industrial PC 500~50 00 m/s 2 Motor electric instrument panel 500~1 000 m/s 2 Optical Lens 500~1 000 m/s 2 Parking Sensor m/s 2 Airbag m/s 2 Fire engine impact test m/s 2 Damage test ISO : Rigid body motion ISO : Hopkinson bar NML High shock ~ m/s 2 Military Equients

Copyright 2014 ITRI 工業技術研究院 Motivation : Fulfill Traceability Chain Extend range to m/s 2 Requests extend to at least m/s 2 U : 2.1 % to 2.6 % U : 1.0 %

Copyright 2014 ITRI 工業技術研究院 1. Calibration capability: ~ m/s 2 U : 2.1 % to 2.6 % Range to be extended 2. Transferring standard calibrated by NML Primary Low shock calibration system. Scope Amplifier Std. Acc. Cal. Acc. Steel ball Air pump Air Throttle Vacuum control Suck device Computer GPIB NML- comparative calibration system

Copyright 2014 ITRI 工業技術研究院 ISO Methods for the calibration of vibration and Shock transducers — Primary shock calibration using laser interferometry Acceleration peak value: 100 m/s 2 to m/s 2 Acceleration peak value: m/s 2 to m/s 2 PC °90° 11 7 Rigid body motion Wave propagation inside a long thin bar - Hopkinson bar Primary shock calibration methods

Copyright 2014 ITRI 工業技術研究院 Primary low shock calibration system: Rigid body motion PC °90° :Shock machine 2: Electromagnetic exciter 3:Airborne hammer 4:Pad 5:Airborne anvil 6:Accelerometer 7:Amplifier 8:Digital waveform recorder 9:Laser 10:Interferometer 11:Light detectors 12:1 st seismic block 13:2 nd seismic block  Calibration capability : 200 m/s 2 to m/s 2  Uncertainty: 1.0 %

Copyright 2014 ITRI 工業技術研究院 Type Force Control Cost Shock acceleration Noise Repeat.Low gHigh g Comp. air OKHigherOKPoorOKQuiet Electro- magnetic BetterLowerBetterOK Electromagnetic Exciter Specification of NML Electromagnetic exciter Input: AC 110/220 V, 1Φ 2W 50/60 Hz Voltage: (0 to 150) V Current: (0 to 10) A Max. output force: 1000 N Comparison of Shock Exciter

Copyright 2014 ITRI 工業技術研究院 Procedures of calibration t2t2 a 2,max t3t3 V 3,max Laser interferometer Anvil Laser interferometer Accelerometer Displace -ment Low pass filter Differen -tiation (Vel.) Low pass filter Differen -tiation (Acc.) a peak Acc. Low pass filter u peak According to ISO :2001 a peak Accelerometer Charge amplifier t1t1 a 1,max u peak

Copyright 2014 ITRI 工業技術研究院 displacement measurement ideally u 1 : 1+cosφ u 2 : 1+cos(π/2+φ) ISO :2001 Methods for the calibration of vibration and Shock transducers — Primary shock calibration using laser interferometry Lissajous figure practically

Copyright 2014 ITRI 工業技術研究院 Interferometer signals : ref: Chien-ming Wu, et al., Correction of nonlinearity in one-frequency optical interferometry, Meas. Sci. Technol. 7 (1996) 520–524 Elliptical parameters are obtained by least squares fitting and then displacements are calculated. Data processing for displacements

Copyright 2014 ITRI 工業技術研究院 30 July 2014 Primary high shock calibration system: Hopkinson-bar

Copyright 2014 ITRI 工業技術研究院 Main components of high shock calibration system InterferometerShock machine 0°90°

Copyright 2014 ITRI 工業技術研究院 Velocity (m/s) Voltage (V) Preliminary results Peak= ms Vel.: ms ms Acc= m/s 2 Sen.=1.079 mV/(m/s 2 ) Signal from Acc. Time (s) Signal from interferometer Time (s) Velocity (m/s) Time (s)

Copyright 2014 ITRI 工業技術研究院 1 st 2 nd 3 rd 4 th 5 th 6 th Avg.Std. Peak value from accelerometer (V) (0.5%) Peak value from laser interferometer (m/s 2 ) (0.07%) Sensitivity from electro- magnetic exciter (mV/(m/s 2 )) (0.6%) Sensitivity calibrated by PTB (mV/(m/s 2 )) Preliminary results

Copyright 2014 ITRI 工業技術研究院 1.A unique compact electromagnetic exciter was built to produce stable shock force for low and high shock calibration systems. 2. Installation and operation of the electromagnetic exciter are simple, automatic operation of the calibration system will later be implemented. 3. Need to complete the uncertainty evaluation and check the system performance with PTB calibrated value. Conclusions