1. On-Site HotBox Calibration System Team 2 Pourya Assem & Paul Lupas Prof. A.C.Singer ECE 445 – Fall 2012

2. Introduction What is this about? –IR Heat Sensor –Transducer Calibration Device Where is it used? –HotBox Monitoring System What is it used for? –Analyze Heat Signature –Analyze Transducer timing –Prevent Derailment

3. Motivation Why is this needed? –Wheel inspection required by Federal Laws –Sensors often go out of calibration Why is this better? –Switch from mechanical to electrical method –Time & Cost efficient –Introduce a standard calibration procedure

4. Field Operations/Inspection

5. System Features Wireless Units: unreachable locations SD Card: further data analysis Graphical interface: user friendly 9V battery powered: portable device

6. High Level Block Diagram

7. Low Level Amplifier

8. Transducer Signals Maximum train speed 65mph –Minimum transducer timing 26.5ms –Signal: 100-250mVpp, 10Hz sinusoid Minimum train speed 20mph –Maximum transducer timing 2.8s –Signal: 100-250mVpp, 3Hz sinusoid

9. Transformers + Fuses Input: 100-250mV sinusoid 3Hz-10Hz Output: 100-250mV sinusoid 3Hz-10Hz Flat Frequency response Minimum phase delay Total isolation Minimum drain current High current protection

10. Transformers + Fuses Freq. Response –1Hz to 2KHz Transducer 1 Transducer 2

11. Transducer Amplifier Input: 100-250mVpp sinusoid 3Hz-10Hz Output: 2VDC rectified sinusoid 3Hz-10Hz 30% Signal Saturation Non-Inverting Config. LNA Low Freq. Gain: 41

12. Transducer Amplifier Amplification limited by internal power consumption –30% saturation @ 2VDC –Level restorer required Freq. Response 1Hz-20Hz

13. Level Restorer Input: 2VDC Rectified and Clipped 3Hz-10Hz Sinusoid Output: 3.3VDC Inverted and Restored 3Hz-10Hz Signal NPN Common Collector Amp. Properly Invert and Restore signal from 2VDC to 3.3VDC

14. Level Restorer NPN Base Voltage NPN Collector Voltage

15. Slicer Input: 2-3.3VDC Inverted and Restored 3Hz- 10Hz Signal Output: 3.3VDC Burst Wave 3Hz-10Hz Trim-off the slow ramp (rise and fall) edges Implemented using TTL Combinational LOGIC –Function as OR Chain Inverters to increase noise immunity

16. Slicer + OR function Level Restorer Signals Sliced Transducers –Sliced/OR-ed signals

17. IR Heat Sensor Signal Signal: 2Vpp with BW of 5-100Hz @ 1VDC offset Bad timing Uncalibrated IR Heat Sensor

18. Active Filter Ideal Input: 2Vpp signal with BW of 5- 100Hz 1VDC offset Output:2Vpp signal with BW of 5-100Hz 1VDC offset Cut-off Freq. 1KHz 20dB Minimum phase delay LNA Gain:1

19. Active Filter Frequency Response 1Hz-3KHz VTC and Phase for 10Hz sinusoid 2Vpp 1VDC offset

20. Active Filter Noise Handling –Input: 800Hz Square Wave –Output: Higher Harmonics Rejection

21. TX Microprocessor Adaptive algorithm –Collects 16 sample points for all speeds

22. XBEE Transceivers Input: –115200 baud rate from TX Microprocessor –Packaged heat samples 2.4GHz Transceiver –unlicensed frequency band –1mW – up to 100feet –Series 1XBEE

23. RX Microprocessor

24. Dual 4 to 1 Mux Both RX XBEE and GLCD require Serial Port of RX Microprocessor Train is present: –Serial Port connected to RX XBEE Train has passed: –Serial Port connected to GLCD Room to add more subsystems

25. SD Card Powered by 3.3V SPI communication Further data analysis –Connect to PC Data saved in memory #434,364,289,213,143,82,36,7,0,10,41,90,152, 224,300,375,#467,518,552,566,558,532,491,43 2,363,287,212,141,81,35,7,0,#*

26. GLCD 115200 baud rate Display signal waveforms –Show signal average –Indicate if above alarm level Receives data from ATMEL 328 Serial Port through the Dual 4 to 1 Mux Data from SD Card mapped to 128x128 pixels

27. User Interface “Reset” button: reset both TX and RX Units “Next” button: navigate through data collected

28. Power Supply 3.3V required for: –XBEE –SD Card –Amplifiers 5V required for: –Microcontroller –GLCD

29. Power Supply Input Voltage: 9V Output Voltage: 3.32V Voltage ripples: 50mV Tolerance < 2%

30. System Testing All Components are chosen from Low Power versions 9V 250mAh Battery: –2 hours continuous use –Inspect 6 long freight trains Estimated Power ConsumptionTested Power Consumption TX Unit: 62mA @ 3.3VDC + 5mA @5VDC = 229mW TX Unit: 70mA @ 3.3VDC + 5mA @5VDC = 256mW RX Unit: 53mA @ 3.3VDC + 70mA @5VDC = 525mW RX Unit: 50mA @ 3.3VDC + 77mA @5VDC = 550mW

31. System Testing Transducer + Heat Signature Signals

32. System Testing 301,237,176,120,72,35,10,0,2,19,50,91,143,201,264,329,#417,47542,563,565,546,508,453,387,313, 237,164,100,48,14,0,4,29,#198,273,349,420,481,528,557,567,556,525,477,415,343,267,193,123,#3, 0,17,52,105,170,244,320,394,460,512,548,566,563,539,495,#298,222,151,88,41,10,0,8,37,83,144,21 5,291,366,435,491,#566,551,517,465,400,327,251,177,111,57,19,0,2,24,64,118,#336,409,472,521,5 54,567,559,532,487,427,356,281,205,135,76,31,#12,45,95,159,231,307,381,449,504,543,564,564,54 4,506,451,382,#162,98,47,14,0,5,30,74,133,203,277,353,424,484,530,555,#523,475,412,264,190,12 1,65,24,2,0,18,55,108,174,247,#*

33. PCB TX Unit Bottom

34. PCB TX Unit Top

35. PCB RX Unit

36. Connection Ports Connection Ports for Transducer + IR Heat Sensor Signals

37. Accomplishments Detect train at different speeds Correct detection of corresponding heat signature Wireless Functionality Graphical Display SD Card data storage Portable RX Unit, battery powered Tested under extremes

38. Difficulties Power Management Establish working link between all modules Control of data flow Simulating Transducer Signals Correct data analysis Calculations/Scaling of real world problem into a working system

39. Further Improvements Improve wireless range (50mW TX XBEE) Change user interface to touchscreen –Replace GLCD and avoid pushbuttons Time stamp the data collected Collect data from multiple tracks: one TX Unit Implement Bluetooth Module –Read data collected using an Android App Software add-ons

40. THANK YOU Questions? Comments? Tomatoes?