Lockheed Martin Challenge Avionics Systems Presentation, Fall 2008

Problem Statement Problem Statement Current UAV technology is not capable of launching vertically using a rail launch system into the atmosphere. This presents the problem of not being practical for use in an urban environment because of the difficulty for soldiers to see preexisting dangers in an urban combat zone with current UAV technology.

Need Statement The Iowa State LM Challenge Team has been asked to design an unmanned autonomous vehicle to take off from a vertical or near vertical pneumatic launch system within the confines of an urban environment. This vehicle will be used to fly low altitude reconnaissance missions prior to U.S. ground troops occupying the designated area.

System Block Diagram

Operating Environment The UAV is to be designed to operate in an urban environment, likely in regions of current military operation such as the Middle East Considerations of ground obstructions, heat, altitude, sand, hostile action

Deliverables Avionics package capable of autonomous navigation of aircraft using user-defined flightplan Camera system capable of 6” target resolution at 100’ Operational range of 1 to 3 miles for video transmission Components integrated for a pneumatically- assisted vertically-launched aircraft

Layout

Schedule

Work Breakdown

Autopilot

Functional Requirements Be capable of autonomously navigating an aircraft using pre-programmed waypoint navigation Support communication with a ground station to display telemetry and position data

Non-Functional Requirements Operate off of 5 or 12V to simplify power system User-programmable to aid in support of vertical pneumatic launch Small size, weight, power requirements

Technical Challenges Complexity and time constraints promote purchase of a commercial autopilot system No commercially available autopilot that supports our method of launch by default Immense G-loads during launch saturate sensors(~15G) Maintaining vertical orientation throughout launch phase Detecting when UAV has left the launcher

Key Considerations Available technical support Support for user programmable control loop Support for custom code/command Ability to handle additional sensors RC override

Key Considerations Ground Station software capabilities Sensors to aid in launch (eg, GPS) Error handling Size Weight Power consumption

Market Survey Micropilot 2128 Procerus Kestral Cloudcap Piccolo O Navi Phoenix/AX These four products satisfy the functional requirements of our system and were deemed as finalists for selection based on their relative merits

Trade Analysis Micropilot 2128 ProsCons Excellent technical support High frequency GPS High customizability (Xtender) Excellent ground station software User defined control loops Allows additional I/O RC override Error Handling Light weight Small size Low saturation point IMU(2 G) Costly

Trade Analysis Procerus Kestral ProsCons High IMU saturation point (10 G) Extensive error handling Lightweight Small size High power consumption Low GPS frequency Poor technical support

Trade Analysis Cloudcap Piccolo ProsCons High frequency GPS Built-in radio modem Simple form factor Low saturation point IMU(2 G) Costly Large size Heavy High power consumption

Trade Analysis O Navi Phoenix/AX ProsCons Low power consumption Small size High IMU saturation point No embedded or ground station software Low GPS frequency

Autopilot Selected Model MicroPilot 2128 –Support for additional sensors increases our chances of safe and reliable launch and recovery –MicroPilot has demonstrated excellent service and support –I/O ports and user-defined telemetry fields provide a superior ability to create a custom platform –HORIZON software provides excellent ground station as well as easy configuration of autopilot –Low saturation point of the IMU accelerometers, we feel can be overcome through the utilization of other onboard sensors and user defined launch sequence –RC override provides us with the option for manual launch.

Video Subsystem Camera, Video Transmitter, Video Receiver, Antennae

Functional Requirements Shall provide real-time video to ground station Shall operate in an urban environment Shall be capable of resolving a 6 inch target from an altitude of 100 feet Shall be a fixed-position camera Shall be designed to enable a modular payload system

Non-Functional Requirements Low-power consumption components Light-weight components Small physical size components Video transmission shall not occur in the 900 MHz band to prevent interference with autopilot communication Components should utilize 5V or 12V when possible to simplify power requirements and increase modularity of design

Camera: Necessary Resolution Below are some sample images taken from a digital camera as a test of the resolving power required in the video system 18 pixels per inch9 pixels per inch4.5 pixels per inch

Camera: Necessary Resolution Given camera has an effective resolution of 768 horizontal lines Ratio of available pixels to linear distance: –0.63 pixels/inch in scenario one –6.54 pixels/inch in scenario two From the last slide, a 4.5 ppi image allows viewer to resolve a 6 inch target. The lens can provide a 6.5 ppi image, which exceeds this requirement Scenario One – Wide AngleScenario Two – Telephoto x = feet x = 9.87 feet

Camera Alternatives Few cameras designed for UAV use satisfy our resolution requirements Many cameras small and light enough are too sensitive for use in our project

Camera Alternatives Genwac/Watec Maker of Industrial Box cameras Adjustable frame rate, easily configurable Heavier than other alternatives Not designed for vibration and varying temperature and humidity of our application

Camera Selection: KT&C model KPC-650 Exceeds resolution requirements Demonstrated ability to perform in UAV’s C and CS mount lens compatible - large variety of varifocal lenses from which to choose Auto-iris compatible - the ability to dynamically adjust to changing light conditions during flight NTSC video output using a coaxial connection (both standard – allows for simplicity of design and video transmission)

Camera Selection: KT&C model KPC-650 Specifications –Power: 12VDC –Effective pixels (NTSC): 768(H) x 494 (V) –Weight: 137 grams –Size: 31mm(W) x 31mm(H) x 55mm(L)

Video Transmitter Must be robust in environments with RF interference Must not interfere with other aircraft systems Direct line-of-sight (LOS) often not possible in an urban environment, reducing transmission range These limitations necessitate a powerful transmitter using a unique frequency FCC regulations limit RF transmissions for civilians (maximum of 1 Watt) A transmitter of 1 Watt will require a Technician Class radio license to operate

Video Transmitter: Estimated Bandwidth Using the Shannon-Hartley Theorem: –C is channel capacity –B is bandwidth in Hz –S/N is the signal-to-noise ratio (SNR) –For a 2.4GHz, 1W transmitter, assuming 10dB of noise: –Standard NTSC signal (704 x 480 pixels at 30 frames/sec.) requires 243Mbps

Video Transmitter: Compensating for Interference Due to obstructions (buildings, etc.) in an urban environment, weather conditions, and altitude, it can be difficult to maintain signal contact Other EM sources present in the area further degrade and interfere with the signal Interference is offset by increased transmission power As will be discussed, antenna choices also have a direct impact on the signal’s transmission range

Video Transmitter Selection: LawMate TM Chosen for maximum allowable power and small size Demonstrated ability to work in UAV’s Standard SMA connector allows antennas to be easily changed Accepts video data in composite NTSC format –Readily compatible with our camera Utilizes a 12V power source, simplifying onboard power requirements

Video Transmitter Selection: LawMate TM Specifications –Power: 500mA at 12VDC –Output: 1W RF power –Weight: 30 grams –Size: 26 x 50 x 13mm

Video Receiver Receiver is subject to less restrictive size, weight, and power limitations Must operate in the 2.4GHz band to receive video signal from selected video transmitter Easy output to the display was also a consideration

Video Receiver Selection: LawMate RX-2480B Chosen for portability and compatibility with our transmitter Includes rechargeable battery – simplifying testing Supports reception on 8 channels with signal indicator to optimize reception Provides output in standard RCA composite video

Video Receiver Selection: LawMate RX-2480B Specifications –Power: 800mA at 5V –Battery life: ~3.5 hrs. –Weight: 135 grams –110 x 70 x 20mm

Video System Antennae Weight, simplicity, range, and frequency (2.4GHz) were the driving factors when selecting an antenna for both the transmitter and the receiver Directional antenna on-board is preferred to omni- directional, but is not practical –Larger size/weight than omni-directional –Increased complexity – must be oriented to ground station at all times during flight Ground station does not share these constraints, and thus a directional patch antenna will be utilized Increases range while maintaining size and complexity only at the ground station

DC-DC Converter Requirements –Facilitate power requirements for onboard systems –Physical size must be small enough to fit easily into fuselage

DC-DC Converter Major Onboard System Power Requirements ComponentCurrent RatingVoltage Rating Video Camera180 mA12 Vdc Video Transmitter500 mA12 Vdc Autopilot Core Vdc4.2 – 27 Vdc Radio Modem730 mA4.75 – 5 Vdc Voltage LevelTotal Estimated Current Total Estimated Power 12 Vdc680 mA8.16 W 5 Vdc817 mA4.085 W

DC-DC Converter Initial Research –Tri-M Systems HESC104 12A 2.5A 3.55 x 3.75 x 0.5 in., 200 grams –Fits power need but too large for fuselage

DC-DC Converter Initial Research –Tri-M Systems IDD A 10A 3A 1.57 x 3.94 in., 58 grams –Meets size and power needs but no enclosure

DC-DC Converter Selection –Murata Power Solutions –TMP-5/5-12/1-Q12-C 5A 1A 3.04 x 2.04 x 0.55 in, 170 grams

Onboard Radio Modem Requirements –Driven by autopilot communication requirements –Minimum range of 3 miles –Physical size must be small enough to fit easily into fuselage

Onboard Radio Modem Initial Research –Xtend-PKG 900MHz Power Supply 7-28V Max Current 900mA Outdoor LOS Range 14 mi x 5.5 x 1.13 in, 200 grams –Physical size too large for our fuselage –Can be used for ground station

Onboard Radio Modem Selection –9Xtend-PKG OEM 900 MHz Power Supply Vdc Max Current 730 mA Outdoor LOS Range 14 mi x 2.38 x 0.02 in, 18 grams

Ground Station and User Interface Requirements –Ability to communicate with and control autopilot –Ability to display real-time video feed –Mobile Must fit in the back of a military humvee

Ground Station and User Interface Components –Driven by onboard component selection –Laptop Computer Able to run HORIZON software package Able to interface with Xtend-PKG radio modem –Portable Television Able to interface with LawMate RX-2480B video receiver Able to accept input from video storage device

Ground Station and User Interface HORIZON Software Package –Satisfies communication, control and telemetry display requirements –Designed by autopilot manufacturer for use with our chosen autopilot system, ensuring compatibility and reliability

HORIZON Software Package

Performance Projected Avionics Endurance: mAh battery - Avionics components draw maximum 1650 mA / 1650 ≈ 1.3 hours Projected Transmission Range: -Based on reports of other users of our transmitter, receiver, and antenna setup report reliable reception out to 2 miles -Variables in our case include RF interference, altitude, antenna orientation Project Requirements: Endurance – 2 hours is a desired max, 1 hour minimum Range – Must be able to cover a small urban area, approximated to 1-3 miles of linear distance

System Testing Video System –Independent from other systems –Test Camera Resolution –Test Camera Communication Quality Range –Antenna Positioning

System Testing Autopilot –Model flight characteristics of UAV during launch, flight and landing phases Provided by Aero and Launch Teams –From models, determine necessary control loops to program using HORIZON Simulate autopilot controls using HORIZON

System Testing Autopilot –Use Aero prototype to bench test autopilot system –Test communication systems Similar procedure to Video System testing –Flight Test

Integration and Test Issues -Integration -Communication: Radio modem and video transmission configuration and use, placement and adjustment of antennas -Configuration: Autopilot configuration to aircraft, configuration of sensors, integrating RC control with autopilot -Test -Restrictions: FCC & FAA regulations -Limitations: Time frame, lack of trained pilot amongst avionics team -Environment: Safety and legal issues prevent testing in target environment

Questions?

Specifications Appendix

Physical Characteristics MicroPilot Weight28 g Dimensions (L x W x H)100 mm x 40 mm x 15 mm Power Requirements Volts Supply Voltage4.2 – 26 V Separate supplies for main and servo powerYes Functional Capabilities Includes Ground Station softwareYes Max # of Waypoints1000 In-flight waypoint modification possibleYes GPS Update Rate1 Hz Number of servos24 Sensors AirspeedYes, up to 500 kph AltimeterYes, up to MSL 3-axis Rate Gyro/Accelerometers (IMU)Yes Accelerometer Saturation Point2 G GPSYes Data Collection Allows user-defined telemetryYes – max 100 Customization User-definable error handlersYes – loss of GPS Signal, loss of RC Signal, loss of Datalink, low battery User-definable PID loopsYes – max 16 Autopilot can be loaded with custom programYes – with XTENDER SDK (separate)

Physical Characteristics Procerus Kestral Weight16.65 g Dimensions (L x W x H)52.65 mm x mm x ? mm Power Requirements500 mA Supply Voltage3.3V and 5V Separate supplies for main and servo powerYes Functional Capabilities Includes Ground Station softwareYes Max # of Waypoints100 In-flight waypoint modification possibleYes GPS Update Rate1 Hz Number of servos12 Sensors AirspeedYes, up to 130 m/s AltimeterYes, up to MSL 3-axis Rate Gyro/Accelerometers (IMU)Yes Accelerometer Saturation Point10 G GPSYes Data Collection Allows user-defined telemetryUnspecified Customization User-definable error handlersYes, Loss of Datalink, Loss of GPS, Low Battery, Imminent Collision, Loss of RC Signal User-definable PID loopsUnspecified Autopilot can be loaded with custom programYes, Developer’s Kit available for $5000 for one year license

Physical Characteristics Cloudcap Piccolo Weight109 grams Dimensions (L x W x H)130.1 mm x 59.4 mm x 19.1 mm Power Requirements5 Watts ( ~ V ) Supply Voltage4.8 – 24 Volts Separate supplies for main and servo powerNo Functional Capabilities Includes Ground Station softwareYes, basic Max # of Waypoints100 In-flight waypoint modification possibleYes GPS Update Rate4 Hz Number of servos6 Sensors AirspeedYes AltimeterYes 3-axis Rate Gyro/Accelerometers (IMU)Yes Accelerometer Saturation Point2 G, 10G with external sensor package GPSYes Data Collection Allows user-defined telemetryUnspecified Customization User-definable error handlersYes User-definable PID loopsUnspecified Autopilot can be loaded with custom programYes

Physical Characteristics O Navi Phoenix AX Weight45 grams Dimensions (L x W x H)88.14 mm x mm x 19 mm Power Requirements84 12V Supply Voltage Volts Separate supplies for main and servo powerNo Functional Capabilities Includes Ground Station softwareNo Max # of WaypointsUnspecified In-flight waypoint modification possibleUnspecified GPS Update Rate1 Hz Number of servos6 Sensors AirspeedNo AltimeterYes 3-axis Rate Gyro/Accelerometers (IMU)Yes Accelerometer Saturation Point10 G GPSYes Data Collection Allows user-defined telemetryUnspecified Customization User-definable error handlersUnspecified User-definable PID loopsUnspecified Autopilot can be loaded with custom programYes, REQUIRED

REPORT DISCLAIMER NOTICE DISCLAIMER: This document was developed as a part of the requirements of a multidisciplinary engineering course at Iowa State University, Ames, Iowa. This document does not constitute a professional engineering design or a professional land surveying document. Although the information is intended to be accurate, the associated students, faculty, and Iowa State University make no claims, promises, or guarantees about the accuracy, completeness, quality, or adequacy of the information. The user of this document shall ensure that any such use does not violate any laws with regard to professional licensing and certification requirements. This use includes any work resulting from this student-prepared document that is required to be under the responsible charge of a licensed engineer or surveyor. This document is copyrighted by the students who produced this document and the associated faculty advisors. No part may be reproduced without the written permission of the course coordinator. Images within this presentation were obtained via the courtesy of their respective owners, listed below: Lockheed Martin Corporation MicroPilot Procerus Cloudcap Technology O Navi Genwac/Watec RangeVideo Tri M Engineering Murata Power Systems Digi Intl.