Team Information Designation Ongo-03 Members • Summer Semester • Chad Winterhof • Eugene Koob • Fall Semester • Scott Dang • Bernard Lwakabamba • Stephen Smith • Nathan Ellefson Advisors Dr. J. Lamont, Prof. R. Patterson, Dr. Rajagopalan, Dr. J. Basart Client Space Systems Operational Lab (SSOL) Department of Electrical and Computer Engineering
Agenda • Problem Statement & General Background • Project Assumptions and Limitations • Design Objectives/Constraints • End-product Description • Risk and Risk Management • Technical Approach • Evaluation of Success • Future Work • Financial and Human Budgets • Lessons Learned • Summary
General Background IARC(International Aerial Robotics Competition) • Annual competition started in 1990 • Sponsored by the Association for Unmanned Vehicle Systems International • University teams build autonomous aerial vehicles that must complete predetermined tasks • Tasks change every 4 to 5 years • The team completing the most tasks in the least amount of time wins
Problem Statement • Build ISU’s first entry in IARC competition • Complete the requirements for the competition • Modify an R/C helicopter for autonomous flight • Establish a communication link between the helicopter and a ground-based PC station
End-product Description • Fully autonomous gas powered helicopter that uses GPS and other sensors to navigate • The ability to transmit analog image signals to a ground station • Ground station able to recognize symbols via image recognition software • Able to enter the IARC
Assumptions • Funding will be available for the completion of the project • Suitable hardware will be available to complete the project • Our design will successfully control the flight of the helicopter used in the project • The sensors chosen for the helicopter will work with the control system to control the helicopter and successfully identify ground markings
Limitations • The payload carrying capacity of the helicopter • Flight time of the helicopter without refueling • Accuracy of the GPS system • Range of the imaging hardware • Range and accuracy of the data transmission equipment • Available funding • Limited mounting surface • Power consumption
Potential Risks • Serious design flaw that halts the development of the aircraft • Helicopter crashes and needs repair • Our funding runs out before the project is finished • Time constraints, rule changes
Current Semester Approach • Focus on sensors: • Compass • Sonar • 2. Need for Helicopter Repair • 3. Flight Training
Technical Approach Control Subsystem • We are planning to use a PC/104 control board as the on-board computer to control the helicopter. • This controller will be interfaced with the sensors and telemetry. • It will take data from the sensors and process it so that it can make flight control decisions. • The control subsystem will reside in the software of the onboard computer.
Technical Approach Control Subsystem Autopilot Servos Helicopter Reaction AFCS Inner Loop AFCS Outer Loop Figure 1. Simple block diagram showing control system interaction with helicopter
Technical Approach Control Subsystem Desired Position Logic Model Helicopter Position Sensors
Technical Approach SLAVE SLAVE SENSOR SENSOR ANALOG 1 ANALOG 2 ADDITIONAL SENSORS CPU DIGITAL Sensors Subsystem Sensor System SLAVE (PIC) • Performs A/D conversions if necessary • Performs segmentation of data • Controls operation of servos ONBOARD COMPUTER • Polls the SLAVE(s) in a predefined order • Packages sensor data and sends to the telemetry subsystem
Technical Approach Sensors Subsystem Current Sensor Components • Polaroid 6500 Ranging Module (2) Altitude & Proximity • Accelerometers (2) Acceleration • Gyroscopes (2) Pitch, Yaw, Roll • Digital Compass Direction Future Sensor Components • GPS Global Coordinate • Imaging System Image Recognition
Technical Approach Information Transfer and Processing -Telemetry Unit- • It will interface with the on-board computer. • This subsystem will relay flight and mapping information to the PC based ground station for processing. -PC Based Ground Station- • The ground station will receive and log sensor data from the telemetry system on the helicopter. • It will also do image recognition on the image relayed from the helicopters on-board video camera. • We have chosen a Dell 500 MHz PC for this job.
Evaluation of Success Past accomplishments • Built and tested helicopter • Designed compass circuit • Created sonar software • Acquired ground station • Acquired flight simulator
Evaluation of Success • Spring ’01 Accomplishments: • Learned to program PICs • Designed basic control algorithm • Created new strategic plan • Designed communications for onboard components • Created interfaces between sensors and PICS
Evaluation of Success Current semester accomplishments • Established contact for Flight Trainer • Helicopter evaluation • Sonar • Compass
Future Work Future Milestones: • Test hardware limitations • Finish development on control/communication software • Learn to fly helicopter manually (ongoing) • Start assembling hardware to mount onto the helicopter • Re-build the helicopter
Only extra helicopter parts and a new instruction manual were purchased for $40.94. Projected costs were $160 for parts and labor for helicopter repair. Table 1 indicates an estimated budget for Micro-CART for the duration of the project. Expected Financial Budget
Lessons Learned • Team work • Meet regularly • Interpersonal communications • Thoroughly document work done • Know the project requirements • Work always takes longer than planned • RISC architecture can be confusing • Advantages and disadvantages of Stamps • Double check contacts • Follow Directions!
Summary Goal: Build autonomous vehicle for entry in IARC competition by 2003 Proposed Solution: Modify a gas-powered remote controlled helicopter for autonomous flight Current Status: 1. Helicopter needs to be re-built 2. Sensor subsystem in the implementation phase 3. Control system entering design phase