Fall 2006 AdvisorsClient Dr. John LamontIowa State University Professor Ralph Patterson IIIDepartment of Electrical and Computer Engineering Primary Vehicle Team Secondary Vehicle Team 2 nd Semester1 st Semester 1st Semester Tim Gruwell (Team Leader) Brian Baumhover Patrick Turner Andrew Larson Bai Shen Byung Kang Erica Moyer Bill Hughes Maria-Cristina Olivas Hassan Javed Jeff Pries (ME) Josh Robinson Pankaj Makhija Brett Pfeffer (ME) Kito Berg-Taylor (AerE) Gustav Brandstrom (ME) Interdisciplinary Members Micro-CART U N M A N N E D A E R I A L V E H I C L E O NGO – 03 Microprocessor–Controlled Aerial Robotics Team

Fall 2006 Presentation Outline Definitions Acknowledgment Problem statement Operating environment Intended users and uses Assumptions and limitations End product requirements Project activity –Previous accomplishments –Present accomplishments –Future required activities Approaches considered Project definition activities Research activities Design activities Implementations activities Testing activities Resources and schedules Project evaluation Commercialization Suggestions for future work Lessons learned Risks and risk management Closing summary

Fall 2006 AttitudeThe orientation of an aircraft's axes relative to a reference line or plane, such as the horizon AUVSI Association for Unmanned Vehicle Systems International CADComputer Aided Design GPSGlobal positioning system GSSGround station system IARCInternational Aerial Robotics Competition IMUInertial measurement unit PC-104x86-based controllable board PICProgrammable interface controller PIDProportional Integral Derivative PitchRevolution of a vehicle forward and backward on a central axis Pro/EProfessional Engineer CAD package PWMPulse width modulation RCRemote control RollRevolution around the longitudinal axis of a vehicle SVSecondary Vehicle UAVUnmanned aerial vehicle WIKI(What I Know Is) A public documentation repository YawRevolution around the vertical axis of a vehicle Acronym Definitions

Fall 2006 Acknowledgement Iowa State University’s Microprocessor-Controlled Aerial Robotics Team would like to give special thanks to the following people and organizations for their assistance: Dr. John W Lamont and Assistant Professor Ralph Patterson III for sharing their professional experience and guidance throughout the course of this project. Lockheed Martin Corporation for their technical expertise and generous financial contribution to this costly endeavor. Without their assistance this project would not be possible. The Department of Electrical and Computer Engineering for creating Micro- CART and providing the skills and knowledge required for this project.

Fall 2006 Problem Statement General Problem Statement –To provide an entry into the International Aerial Robotics Competition (IARC) Summer 2007 for Iowa State University General Solution Approach –Develop an aerial vehicle to compete in IARC Level 1 –Develop a secondary vehicle for higher level IARC –Main system components PC-104 embedded system IMU GPS unit Battery power supply Sonar array Digital magnetic compass Wireless modem

Fall 2006 IARC (International Aerial Robotics Competition) Diverse indoor/outdoor environments Obstacles defined by the competition mission Temperature threshold (60 o -100 o F) Possible wind, light precipitation, adverse topography of the competition location No extreme environments, e.g. fog, rain, etc. Operating Environment

Fall 2006 Initial Users Spring 2007 Micro-CART team members –Responsible for operating vehicle in summer 2007 IARC Future Users Future Micro-CART teams Researchers Industry representatives Hobbyists Intended Users

Fall 2006 Initial use Entry into Summer 2007 IARC Future uses Search and rescue Military and law enforcement reconnaissance Environmental catastrophe control Intended Uses

Fall 2006 Assumptions IARC Mission rules may change Necessary funding remains available Suitable hardware and software is available at an affordable price Onboard computing systems will be sufficient Current vehicle able to carry necessary equipment On-board memory sufficient Sensor system will provide all necessary flight software inputs Attachment of secondary vehicle to primary vehicle Assumptions and Limitations

Fall 2006 Limitations Physical limits of helicopter Obstacle detection and avoidance Power consumption limits Competition maximum weight limit Competition requirements Team member expertise Weather Assumptions and Limitations

Fall 2006 Primary Vehicle IARC Level 1 Autonomous Functionality Take off Navigate to five waypoints with the fifth located three kilometers away Maintain a stable hover at the fifth waypoint Secondary Vehicle Higher level IARC Functionality Communication with Primary Vehicle Image Recognition Obstacle Avoidance End Product Requirements

Fall 2006 Presentation Outline Definitions Acknowledgement Problem statement Operating environment Intended users and uses Assumptions and limitations End product requirements Project activity –Previous accomplishments –Present accomplishments –Future required activities Approaches considered Project definition activities Research activities Design activities Implementation Activities Testing Activities Resources and schedules Project evaluation Commercialization Suggestions for future work Lessons learned Risks and risk management Closing summary

Fall 2006 Project Activity Previous Accomplishments Acquired helicopter, system components, and sensors Flight test stand modifications Present Accomplishments First autonomously hovering flight on Sept. 26 th, 2006 Sonar developed and successfully implemented New Lithium Polymer battery purchased Testing procedures and Pre-Flight systems check list created

Fall 2006 Previous Accomplishments Fall 1999 Purchased RC helicopter Purchased Dell PC Fall 2000 – 2003 Pilot training program Spring 2002 Acquired security box Fall 2002 Acquired and setup Linux PC Sonar circuit design Complete PIC programming for serial interfacing Fall 2002 – Spring 2003 Hardware acquisitions Serial software development PIC programming PC-104+ operating system Spring 2003 Power system Mounting platform Manual override switch Fall 2004 Replace PC-104+ Purchased Dell PC Spring 2005 Acquired Wireless Data-link Acquired Magnetic Compass Fall 2005 WIKI Hardware enclosure New head block Flight test stand modifications Flight testing Onboard payload limitations Spring 2006 Untested altitude flight control code Flight simulator software ported to Linux Flight test stand modifications Developed exhaust shield GPS research and replacement

Fall 2006 Present Accomplishments Sonar –A/D RS232 Module –MINI-A Transducer New Lithium Polymer Battery –Much higher Power-to-Weight Ratio New flight control software First autonomously hovering flight on Sept. 26th, 2006 Testing procedures and Pre-Flight systems check list created

Fall 2006 Future Activities Compete in level one IARC Complete flight control code Test fully autonomous flight Research and plan trip to the competition

Fall 2006 Future Activities Continue planning and development for higher IARC levels Level 2 –Image recognition –Object avoidance Level 3 –Deployment of the secondary vehicle –Image recognition –Object avoidance

Fall 2006 Approaches Considered ActivityApproachesAdvantagesDisadvantagesChoice Flight ControlUsed C++ instead of C language. -Object Oriented Programming is easy for modifications. -Might be slowerAccepted Code Comments on Doxygen -Nice Layout and it does everything automatically. Accepted Writing data to the CF card or to the RF modem. -Sends sensor logs to RF modem and that in turn sends it to the Ground Station for logging. -Write Speeds may be limited. -Might lose packet information. Accepted

Fall 2006 Approaches Considered ActivityApproachesAdvantagesDisadvantagesChoice SonarNew circuit design for Sonar -Do not need the Trigger Circuit and the MUX. -Implementing a program can retrieve the data from the Sonar. Accepted Secondary VehicleMulti-rotor-More lift capacity-Very unstableRejected Contra-rotation.-Fewer components and more stability. -Less liftAccepted

Fall 2006 Project Definition Activities (SV) IARC Requirements - Fully autonomous - Carried and launched by primary vehicle - 1m x 1m building entrance -Safely navigate into the building - Ability to obtain images - Relaying images back to ground station through primary vehicle

Fall 2006 Research Activities Research Aims: Full understanding of vehicle and component behavior Minimize wasted development time Ensure suitability of components Research Areas: Existing component performance Flight control algorithm design New Topics –Debugging and Datalogging –Code Documentation –Optimal Control Frequency

Fall 2006 Research Activities Existing Component Performance Operational Limits Precision Accuracy Reliability Quirks

Fall 2006 Research Activities - IMU Operational Limits: –Missing spec. sheet limits precise knowledge –Assumptions made based on mfg. manual ±2g Accelerometers ±100º/sec Rate Sensors –Onboard Kalmann filter provides angular position –Temperature Compensated Accuracy and Precision –Precision to 0.01º and 0.01m/s2 –Angular position, rate and linear acceleration highly accurate Quirks –Intermittent failure to initialize –Mounted upside down on helicopter

Fall 2006 Research Activities - Compass Operational Limits: –Compass must be level for accurate readings –Cannot operate within 1.5' of main rotor shaft Accuracy and Precision: –Lacked accuracy within the test environment –Readings disputed by traditional compass Requires in-flight testing to ascertain reliability Magnetic interference around main rotor shaft

Fall 2006 Research Activities - PC-104 HESC Power Supply –Produces 5V and 12V power –6V to 40V input range –High likelihood voltage fluctuations will cause power supply failure. Serial Port Add-on Board –IRQ sharing creates massive delays –To achieve parallel data streaming each port must be assigned unique IRQ

Fall 2006 Research Activities - GPS Uses standard NMEA protocol Interface has to be reverse engineered from proprietary software. Cannot obtain signal indoors

Fall 2006 Research Activities Flight Control Algorithm Existing software was written in C and used a multi- layered approach Large quantities of code were missing Control revolved around a PID –PID is well-suited to onboard helicopter control –PID was incorrectly and incompletely implemented Excessive threading contributed to complexity Hardware interfaces were buggy but mostly complete Code translated well to object-oriented design

Fall 2006 Research Activities New Topics Debugging and Data logging –Real-Time In-Flight feedback –New debugging framework –Unit Tests Code Documentation –Doxygen Optimal Control Frequency –Comparison with other vehicles

Fall 2006 Presentation Outline Definitions Acknowledgement Problem statement Operating environment Intended users and uses Assumptions and limitations End product requirements Project activity Previous accomplishments Present accomplishments Future required activities Approaches considered Project definition activities Research activities Design activities Implementations activities Testing activities Resources and schedules Project evaluation Commercialization Suggestions for future work Lessons learned Risks and risk management Closing summary

Fall 2006 Design Activities Hardware New sonar hardware –Serial I/O Board –New Transducer Kill switch Wiring and mounting of components –sonar –compass –power supply wiring

Fall 2006 Design Activities Sonar Ultrasonic transducer –Downward facing –6” to 20' range –Analog signal wired to I/O Board I/O Board –RS-232 interface –Room to easily add up to 7 additional transducers

Fall 2006 Design Activities Software Previously existing design –Old design found to be unimplemented except for basic hardware interfacing code –Concluded that existing architecture was inappropriate – too much threading added unneeded complexity and overhead

Fall 2006 Design Activities Software Defined new architecture –Simplified, tighter control loop and eliminated unnecessary threading –Rewrote much of controller code in a cleaner, object- oriented way –Included integrated debugging and logging module, unit tests, and software emulation of each hardware sensor module

Fall 2006 Implementation Activities Divided components among team members Rewired helicopter –prevent confusion Rewrote flight control code –reuse hardware interface code –control algorithm using PID Mounted remaining components

Fall 2006 Testing and Modification Activities Software Tests Test individual components with new software Run software on helicopter Unit testing Reliability –Code does not exhibit any reliability problems Error tolerance –Program found to be tolerant of failures in everything but IMU Speed Issues –20Hz decided upon as minimum acceptable speed for control loop frequency –Hardware limit appears to be ~45Hz

Fall 2006 Testing and Modification Activities Hardware Tests check functionality of all components being mounted on helicopter check functionality of newly built components sensor interaction –IMU initialization and polling code stress-tested –Sensor input tested for helicopter 's full range of motion Helicopter Control check servos have new team members learn controls

Fall 2006 Research Activities (SV) Previous Design Design Alternatives –Alternative Solutions to IARC Criteria Components –Necessary Components –Previously Purchased Components

Fall 2006 Research Activities (SV) Previous Design Function and advantages Missing documentation Requirements for functionality

Fall 2006 Research Activities (SV) Design Alternatives Ground based solutions Wing-body options Multi-rotor Contra-rotation

Fall 2006 Research Activities (SV) Necessary Components –Size and weight –Integration with other components –Power requirements Microcontroller IMU Transceiver –Bandwidth –Range

Fall 2006 Research Activities (SV) Current Components –Function and operation Motors –Power requirements –Integration with speed controllers Speed Controllers –Integration within current design –Integration within test stand

Fall 2006 Design Activities (SV) Test Stand Reason: Test lift capacity of contra-rotation. Design: Floating plate, spring tensioned design.

Fall 2006 Design Activities (SV) Secondary Vehicle Frame Reason: New vehicle concept requires all new layout Design: Coaxial, contra-rotating rotors create a design similar to standard helicopter.

Fall 2006 Implementation Activities (SV) Current Design Status Development of chassis CAD models Selected onboard components Development of test stand before chassis construction

Fall 2006 Implementation Activities (SV) BladeRunner R/C Helicopter Contra-rotation proof of concept Study passive stability system Motivated by concerns regarding control solution for current design BladeRunner commercial model

Fall 2006 Testing Activities (SV) Previous Secondary Vehicle Design Quad-rotor design presents controllability issues Material availability Competition constraints XUFO test results not promising Motivation for design alternatives Current secondary vehicle design Commercial XUFO

Fall 2006 Testing Activities (SV) Contra-Rotation Test Stand Evaluate lift capacity of two motors Evaluate stability and yaw control Evaluate battery life

Fall 2006 Presentation Outline Definitions Acknowledgement Problem statement Operating environment Intended users and uses Assumptions and limitations End product requirements Project activity Previous accomplishments Present accomplishments Future required activities Approaches considered Project definition activities Research activities Design activities Implementations activities Testing activities Resources and schedules Project evaluation Commercialization Suggestions for future work Lessons learned Risks and risk management Closing summary

Fall 2006 Resources Estimated and actual personal hours Total Hours Average 80 hours per team member Hours CategoryEstimated HoursActual Hours Team Leader Software Subteam Ground Station Subteam Hardware Subteam Secondary Vehicle Subteam Total

Fall 2006 Resources ItemPrevious Total CostActual Cost for Fall 2006Total Project Cost to Date Sensor Systems GPS $ 5, $ $ 5, IMU $ 5, $ 0.00 $ 5, Sonar $ $ $ Magnetic compass $ $ 0.00 $ Wireless comm link $ $ 0.00 $ Ground station PC $ 0.00 $ Flight Controls PC/104 $ 1, $ 0.00 $ 1, Servo controller $ $ 0.00 $ Manual override switch $ $ 0.00 $ Emergency shutoff switch $ $ 0.00 $ Vehicle Configuration Power supply / battery $ 1, $ $ 1, Helicopter / maintenance $ 6, $ $ 6, Flight Augmentation Stand $ $ 0.00 $ Total Hours10,7711, , Labor ($10.50 per hour) $ 113, $ 12, $ 125, Total Costs (w/o labor) $ 21, $ $ 22, Total Costs (w/ labor) $ 134, $ 13, $ 148,094.83

Fall 2006 Schedules

Fall 2006 Schedules

Fall 2006 Project Evaluation ComponentTasks Current Status GPS softwareTest and verifyIncomplete Mounting schemeImplement, test, and verifyComplete SonarPurchase, test, and verifyComplete Sonar softwareDevelop, test, and verifyComplete Compass softwareTest and verifyComplete Wireless data linkTest and verifyComplete Flight Control SoftwareDebug, test, and verifyIncomplete Composite enclosure Design, lay-out, and purchase composite hardware Complete

Fall 2006 Project Evaluation ComponentTasksCurrent Status Autonomous hoverTest and verifyComplete Autonomous flightTest and verifyIncomplete Helicopter electronicsTest and verifyComplete HelicopterDetermine center of massIncomplete Test standAcquireComplete Translational flight controllerComplete, test, and verifyIncomplete Senior designUpdate websiteComplete Senior designFulfill reporting requirementsComplete Senior designDocument on the WikiIn Progress

Fall 2006 Commercialization At this time, the project will not be commercialized –Too large, too fragile for military applications –Too expensive for civilian applications Future –Military –Reconnaissance and surveying –Hazardous site clean-up –Search and rescue –Traffic control and enforcement

Fall 2006 Recommendations Continue as originally envisioned –Automated helicopter is close to flying –Project will no longer suffer “memory loss” –Micro-CART is a worthwhile learning experience

Fall 2006 Lessons Learned Take care when testing Document thoroughly Start deliverables early

Fall 2006 Risk and Risk Management Risk: Loss of team member Management: Have proper documentation Overlapping team member skills Risk: Damage to components Management: Create accurate testing procedures Understand the “Big Picture” Risk: Personal injury during testing Management: Stay alert Maintain communication Risk: Lack of expertise Management: Consult advisors Research and learn

Fall 2006 Closing Summary Project has had it’s hurdles, but progress is still being made and we will be ready to compete in Summer Micro-CART is a challenging project encompassing control systems, mechanical systems, hardware, and software. It also gives students an excellent way to broaden their experiences, build problem solving skills, and learn responsibility. Bottom Line: Micro-CART is a valuable and interesting project and should be continued in Senior Design.

Fall 2006 Questions?