1 / 54

Project “ RedEye ”

Project “ RedEye ”. University of Central Florida College of Electrical Engineering and Computer Science Senior Design Fall 2011. Group 8 David Morrow Ricardo Rodriguez Shane Theobald Nick Bauer. Motivation. Wanted to gain experience in many different engineering disciplines C# - GUI

storm
Download Presentation

Project “ RedEye ”

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Project “RedEye” University of Central Florida College of Electrical Engineering and Computer Science Senior Design Fall 2011 Group 8 David Morrow Ricardo Rodriguez Shane Theobald Nick Bauer

  2. Motivation • Wanted to gain experience in many different engineering disciplines • C# - GUI • Optics – Laser Range Finder • Wireless Communication • Controlling Peripheral Devices via Microcontroller

  3. Goals • Calculate the GPS coordinates of a user specified target using the following components. • Wireless Camera • Laser Rangefinder • Digital Compass • GPS Module • Minimize • Cost • Weight • Power Consumption

  4. Project Specifications • Target Specs • 5m minimum distance • 100m maximum distance • 10m x 10m minimum target size • Accuracy • Rangefinder distance within ±10m • Self GPS coordinates within 5m radius of true location • Compass heading within ±1° of true heading • Final target GPS coordinates within 50m radius of true location

  5. Block Diagram

  6. Operational Flow Chart

  7. Rangefinder Subsystem • Methods of Laser Rangefinding • Triangulation • Easiest method both conceptually and design • Based on geometry • Increasingly less accurate as range increases • Interferometry • Most accurate method of laser rangefinding • Can measure small distances on order of wavelengths • Time-of-flight • Can measure very large distances with great accuracy • This is the approach that we will implement

  8. Time-of-Flight Rangefinder

  9. Receiver Module Components • Photodetector • HV Power Supply • Front End Amplifier (Transimpedance Amp) • NIR optical filter • Receiver Lens

  10. Avalanche Photodiode (Detector) • Pros • Highly Sensitive Photodetectors • Make use of avalanche multiplication for increased gain • High Speed • Designed for rangefinder applications • Allows for larger maximum range detection • Cons • Require HV reverse bias to get maximum gain • Exhibit higher dark current than alternatives • Small active area makes alignment difficult

  11. APD Design Characteristics • Peak Spectral Response • Cost and Availability • Minimum Dark Current • Required Bias Voltage

  12. Pacific Silicon AD230-9 • Enhanced for NIR detection at 900nm • Low noise equivalent power = 10fW/√Hz • TO-52 Package allows for easy mounting Spectral Response at M = 100

  13. HV Power Supply—EMCO A025P • Proportional Input/Output Voltage • 250VDC when full 5V input applied • Low peak-to-peak ripple (<1%) • Maximum Output Current 4mA • Low turn on voltage of 0.7V

  14. Transimpedance AmplifierTI OPA656 • Converts photocurrent into voltage • High Slew Rate at 290V/µs • Low Input Noise Voltage 7nV/√HZ • FREE—Sampled

  15. Receiver System Schematic

  16. Optical Bandpass Filter • Filter Specs • 2 in X 2in X .1in • CWL 905.9nm • BBW 54.0nm • Peak transmission 79%

  17. Receiver Prototype Overview Lens Tube Assembly Receiver Electronics

  18. Threshold Detection • Prevent False Alarms • Capture as much energy as possible • Keep noise floor low • Set threshold

  19. Laser Transmitter Design Parameters • Output Power—Need high power laser diode to meet maximum range criterion • Pulsewidth—Must have short pulsewidth to have high axial (range) resolution (V x τp) • Wavelength—Transmitter near peak responsivity of photodetector. • Beam Divergence—low divergence angle to ensure maximum energy on target

  20. Laser Diode Options HA!

  21. Laser Diode • SPL-PL-90_3 • TO-18 Package • Divergence 9 x 25 gradient degrees • Minimum Rise/Fall time 1ns • Threshold Current 0.75A • Peak wavelength 905nm • Power output 75W • Peak Current 40A • Typical Voltage 9V • Pulsewidth 5-100ns 5mm 5.9mm

  22. Diode Driver CCAIXYS PCO 7110-50-15 • Pros • Very small in size at 1”x2.5” • Produces fixed pulsewidth at 15ns • Can produce up to 50A diode drive current • Diode mounts easily to CCA. (Radial or Axial options) • Cons • Also requires high voltage source • 33ns propagation delay • Difficult T-zero capture

  23. Diode Driver continued • Supply Current • Ips = (Cpfn + Cfet + Cstray) * Vin * f • Ips = (4000pF + 120pF + 430pF) *195V *1Hz =0.9µA • Output Current • Directly dependent on HV supply (195V is max)

  24. Diode Driver Continued • JP1 Connection

  25. Laser Transmitter Diagram

  26. Transmitter Prototype Overview Transmitter Electronics

  27. Voltage Requirements • High Voltage • Diode Driver Board – 195Vmax • Avalanche Photodiode – 230V • 15V • Diode Driver Board • 10-13V • Camera System • ±5V • Comparator • Op Amps • 5V • High Voltage Power Supply • 3.3V • Microprocessor • TDC

  28. Power Supply Overview

  29. PCB Overview • Designed and Build using ExpressPCB

  30. TDC: ACAM GP2-G590 • Creates a digital value for the laser pulses time of flight from the transmitter to the receiver. • 2 channels with 50 ps rms resolution • Measurement from 3.5ns to 1.8ms • Fire pulse generator • I/O voltage 1.8v – 5.5v • Core voltage 1.8 – 3.6v • 4 wire SPI interface • QFN 32 Package 5mm 5mm

  31. Software Design • Microcontroller • Programming Language: C • Development Environment: Arduino Uno IDE • Handles data collection and peripheral control • GUI • Programming Language: C# • Development Environment: MS Visual Studio • Receives user input and displays relevant information

  32. Embedded Overview Compass GPS MCU XBee TDC Pan & Tilt

  33. MCU: ATmega328 Clock Speed Core Size I/O Pins Package Size Memory UART/I2C/SPI/PMW Operating Voltage Price 16 MHz 8 bit 14 DIP 28 32 kB 2 / 1 / 2 / 6 1.8 – 5.5V $6.27 • Mounted on Arduino development board • Arduino Uno development environment compatibility

  34. IDE: Arduino Uno • C Programming language • Allows for flexible troubleshooting • Large support community • SPI, I2C, & Serial libraries

  35. GPS: EM-406A SiRF III  4.5 – 6.5V 44 mA 4800 1.023 MHz UART; RS-232 5m WAAS $59.95 Input Voltage Input Current Baud Rate C/A code Comm. Protocol Accuracy Price 5cm 5cm

  36. Compass: HMC6352 2.7 – 3V 2 – 10mA 0.1 gauss 0.5 degrees I2C 0.14 grams $34.95 Input Voltage Input Current Field Range Resolution Comm. Protocol Weight Price • Two axis digital compass • Provides heading in degrees from magnetic north

  37. Wireless Comm: Overview • 100ft radial distance • Omni-directional link • Low Power Consumption

  38. Wireless Comm: XBee Series 2 2.8 – 3.6V 40 mA 2 mW (+3 dBm) -98 dBm 250 Kbps 1200 – 1 Mbps 2.4 GHz 133ft 400ft Zigbee (802.15.4) Whip (dipole) $25.95 (X2) Input Voltage RX/TX Current Transmit Power TX Sensitivity RF Data Rate Baud Rate Frequency Band Indoor Range Outdoor Range Protocol Antenna Price 3cm 3cm

  39. Servos: Hitec HS-422B 4.8 – 6V .18 sec/600 83.3 oz*in 450 8.8 mA / 180 mA 3 Pole Ferrite 1.59 oz $16.99 Operating Voltage Operating Speed (6V) Stall Torque Operating Angle Current Drain (6V) Motor Type Weight Price

  40. Pan & Tilt: Hitec SPT200 5.5 oz 135o 2 lbs $45.99 Weight (w/o servos) Tilt Swing Max. Payload Price

  41. Schematic Overview

  42. Camera and Tx/Rx • DIY Security Camera Kit • NTSC format • 510x492 pixels • 900MHz Tx/Rx combo

  43. GUI Functional Flow Diagram Connect to XBee and Video Open GUI User Input no yes Fire Laser Move Camera Poll GPS Poll Compass Display Info

  44. GUI - UML Diagram PositionalData RangeFinder Target • double CompassHeading • - double latitude • - string LatitudeHeading • - double longitude • - string LongitudeHeading + PositionalData Info + int distance + PositionalData targetData + RangeFinder rangefinderData • - PollGPS() • PollCompass() • - PollLaser() • - DisplayData() • CalculateGPS() • DisplayData()

  45. GUI – Layout

  46. Target GPS Algorithm • Given: • Self GPS Coordinates • Latitude (N/S ddmm.mmmm) • Longitude (E/W ddmm.mmmm) • Distance to target (m) • Heading clockwise from magnetic north (deg) • Calculate: • Target GPS Coordinates • Latitude (N/S ddmm.mmmm) • Longitude (E/W ddmm.mmmm)

  47. Target GPS Algorithm – cont. • Spherical Law of Cosines • Self GPS coordinates (lat1, lon1) • Distance to target (d) • Heading (Θ) • Radius of the earth (R) • Target GPS coordinates (lat2, lon2) lat2 = sin-1[ sin(lat1)*cos(d/R) + cos(lat1)*sin(d/R)*cos(Θ) ] [ ] lon2 = lon1 + tan-12 cos(lat1)*sin(d/R)*sin(Θ) cos(d/R) - sin(lat1)*sin(lat2)

  48. Budget

  49. Responsibility Matrix – Phase 1

  50. Responsibility Matrix – Phase 2 & 3

More Related