AEM 5333 – Design, Build, Model, Simulate, Test and Fly Small
Uninhabited Aerial Vehicles
Course Content Overview
Spring 2013
Bérénice Mettler
Part I: Uninhabited Aircraft Missions, Platforms and Systems
1. Overview of System-Oriented Design and Analysis
- Course overview and organization.
- Historical overview and motivation.
- Introduction to systems-oriented approach.
2. Missions
- Existing civilian and military applications.
- Future applications and challenges.
- UAV mission requirements and specifications for design project.
3. Aircraft Platform
- Aircraft types.
- Components (airframe, propulsion, actuators, etc.).
- Effects of size.
- Derivation of vehicle and component level requirements.
Materials and resources:
- Section 1.1, System Architecture, Beard & McLean. (R)
- Section 1.2, Design Models, Beard & McLean. (R)
- Introductory Slides, Prof. G. Balas. 2010. (DB)
- Air Force UAVs: The Secret History, T. Ehrhard, 2010, The Air Force Association.
(DB)
Additional Readings:
- Paper on platform comparison using spatial cost-to-go method, Kong&Mettler
2010. (DB)
- Notes on scaling effects, B. Mettler. (DB)
Assignments:
- Selection of candidate UAV radio/controlled plane.
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Part II: Components and System Architecture
1. Sensors and Actuators
- Overview of sensors and functions (IMU, GPS, etc.).
- Sensors physical measurement principle.
- Servo actuators.
2. System Architecture
- Overall system-level architecture.
- Definition of interfaces between components (Digital/analog I/O, PWM signals, RS232, Universal Serial Bus (USB), Ethernet, CAN Bus).
- Flight computer (CPU architectures).
- Software system, real-time operating systems.
- Communication.
- Overview of avionic systems.
Materials and resources:
- Section 1.1, System Architecture, Beard & McLean, 2012. (R)
- Chapter 7, Sensors for MAVs, Beard & McLean, 2012. (R)
- Exhibit of UMN Ultrastick UAV architectures, components, interfaces and avionics,
flight computer and software. (DB)
Additional Readings:
TBD
Part I-II Assignments:
- Mission level requirements and specifications
- Aircraft specifications as derived from mission requirements
- Component selection
Part III: Aerodynamic and Dynamic Modeling and Simulation
1. Modeling Overview
- Brief review of first principles modeling of a fixed wing aircraft.
- Modeling approaches and model forms (component-wise, transfer function, statespace).
- Modeling requirements (simulation, control design, etc.).
- Review of longitudinal and lateral-directional state-space and transfer-function
models.
- Empirical determination of Ultrastick physical and aerodynamic characteristics
(mass properties and primary aerodynamic coefficients).
3. System Identification
- Overview and general principles.
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- Overview of system identification methods.
- Frequency domain identification (transfer function extraction, model fitting).
4. Kinematic Models and Miscellaneous
- Flight kinematics and wind triangle.
- Modeling atmospheric disturbances.
Materials and resources:
- Paper: System identification of the Ultrastick, Dorobontu et al., 2013. (R)
- Presentation: System identification of the Ultrastick, Dorobontu et al., 2012. (R)
- Section 2.3 Airspeed, Wind Speed and Ground Speed, Beard & McLean, 2012. (R)
- Section 2.4 The Wind Triangle, Beard & McLean, 2012. (R)
- Section 4.4 Atmospheric Disturbances, Beard & McLean. (R)
Part III.1 Assignments:
- Linear and nonlinear simulation UAV model development in Simulink including
wind modeling; simulation, trim, linearization of UAV model and kinematics
- Extracted linear models from flight-test data
- Setup of Simulink linear aircraft models. Modeling of individual vehicle
components (i.e. actuators, sensors, sample rate, filters, winds, commands, etc.).
- Testing and refinement of aircraft models based on flight data
Part III.2 Assignments:
- Extract nonparametric linear frequency response models of the UAV from flight
test data
- Identify parametric 1st and 2nd order transfer function models with time-delays
from frequency response data (actuator, longitudinal and lateral-directional)
- Update Ultrastick Simulink model
Part IV: Control Design
1. Control Augmentation
- Overall control architecture.
- Inner and outer-loop flight control design for fixed wing aircraft.
- Actuator saturations.
- Longitudinal and lateral-directional control loops.
2. Control Design Methods
- Classic control design.
- Model-based designs.
- Pole placement.
Materials and resources:
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- Chapter 6, Autopilot Design Using Successive Loop Closure, Beard & McLean, 2012.
(R)
Part IV Assignments:
- Design longitudinal and lateral-direction control laws
- Generation of real-time control
- Implementation and testing of longitudinal and lateral-directional axis flight
controllers in simulation model
- Analysis and design of flight controllers for Ultrastick aircraft longitudinal and
lateral-directional axes
Part V: Test and Evaluation
1. Experiment Design
- Identify objectives, requirements, and technical approach.
- Plan how system will be tested to verify that it meets the requirements and
validate that it meets the objectives.
- Identify sensors needed and design flight maneuvers.
2. Ultra Stick Simulation Environment
- Simulink nonlinear aircraft model development based on equations of motion,
wind tunnel data and flight data.
- Simulation, trim, linearization of nonlinear UAV model.
3. Software and Hardware-In-the-Loop Evaluation Practices
- Concept of linear simulation for control law development, non-linear simulation
for control law analysis, and HIL simulation to verify and validate performance on
flight hardware.
- Introduce the concept of model uncertainty, ranges of parameters.
- Use of Monte Carlo simulations to verify and validate design robustness.
4. Flight-Testing and Evaluation Practices
- Flight readiness documents
- Relate flight test results to objectives, requirements, and simulation results
Materials and resources:
-TBD
Additional Readings:
-TBD
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Part V Assignments:
- Define trajectories and input sequences for flight tests. Write Objectives and
Requirements Document.
- Implement and test flight control laws in linear and nonlinear Simulink aircraft
equations of motion.
- Integrate C subroutines into Simulink using S-functions.
- Test simulations. Discuss generation of real-time software using C subroutines and
Simulink Real-time Workshop.
- Verify and validate (V&V) control laws meet vehicle and mission level
specifications through Monte Carlo and worst-case simulation.
- Implement and test in software-in-the-loop and hardware-in-the-loop simulation
control, guidance and navigation algorithms. Verify and validate control law
performance on flight hardware through HIL testing.
- Write Test Readiness Review document to discuss how you are going to test your
control laws in flight.
- Analyze flight test data and compare with objectives, requirements, and
simulations.
Part V Assignments:
- Testing and validation of real-time algorithms in hardware-in-the-loop setup;
- Real-time systems, validation of flight test data, algorithms and models.
- Flight test and evaluation
- Flight test redesigned algorithms and compare with simulation.
Part VI: Navigation and Guidance
1. Guidance and Navigation
- Overview of guidance and navigations architectures.
- Path following control.
- Waypoint guidance.
- Vision-Based Guidance.
2. Autonomous Guidance
- Overview of path planning methods (heuristic, trajectory optimization).
- Obstacle field navigation.
- Motion primitive automaton.
- Exteroceptive sensors (laser scanners, flash lasers, radar).
3. Human-in-the-Loop Guidance
- TBD
Materials and resources:
- Chapter 9-12, Design Models for Guidance, Straight-line and Orbit Following, Path
Manager, Path Planning, Beard&McLain, 2012. (R)
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- Chapter 13, Vision-guidance Navigation, Beard&McLain, 2012. (R)
Additional Readings:
- Dubin (…)
- Kufner (…)
- Mettler&Bachelder (…)
- Dadkhah&Mettler (…)
Part VI Assignments:
- Integration of navigation and guidance algorithm modules into nonlinear UAV
simulation.
- Generation of real-time navigation and guidance algorithms for integration into
flight control computer.
- Redesign flight control algorithms, filters, trajectories, waypoints, etc.
- Compare flight test results of original and redesigned controller. Lessons learned.
- Final report.
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