STARMACThe Stanford Testbed of Autonomous Rotorcraft forMulti-Agent Control

Gabe Hoffmann, Haomiao Huang, Vijay Pradeep, Steven WaslanderAeronautics and Astronautics, Stanford University

Claire TomlinAeronautics and Astronautics, Stanford UniversityElectrical Engineering and Computer Science, UC Berkeley

MURI Review Meeting

Frameworks and Tools for High-Confidence Design of Adaptive, Distributed Embedded Control Systems

Berkeley, CA

September 6, 2007

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STARMAC

Testbed Composition 6 quadrotor helicopters

Autonomous UAVs Onboard computation & sensors State and environment estimation Attitude, altitude, position and

trajectory control

Testbed goals Quadrotor UAV design Cooperative multi-agent control Mobile sensor networks

Stanford Testbed of Autonomous Rotorcraft for Multi-Agent Control (STARMAC)

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Quadrotor Features

Vertical Takeoff and Landing (VTOL) Easy to use indoors and outdoors No runway required

Safety Rotor kinetic energy distributed to 4 blades Rotors can be within the frame

• Can fly indoors without harm to user or aircraft Control Design

More linear than standard helicopters Maintenance

Few moving parts Durable exterior protects contents

Cost Can be fabricated in the lab Made of low-cost parts Low maintenance requirements

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STARMAC Development

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STARMAC Quadrotor Helicopter

BatteryLithium Polymer

BrushlessDC MotorsAxi 2208/26

Sonic RangerSRF08

Inertial MeasurementUnit (IMU)3DMG-X1

High LevelControl Processor

Stargate SBCor PC/104

Low Level Control Processor

Robostix

GPSSuperstar II

Electronic Speed

ControllerPhoenix 25

Plastic Tube Straps

Carbon Fiber Tubing

Fiberglass Honeycomb

LIDARHokuyo

URG-04LX

Stereo VisionVidere Systems

Small Vision System

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Quadrotor Helicopter Actuation

Yaw Torque

Roll/Pitch Torque Total Thrust

Two pairs of counter rotating blades provide torque balance

Angular accelerations and vertical acceleration are controlled by varying the propeller speeds.

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STARMAC Network

WifiNetgear

Rangemax 802.11g+

≤ 54 Mbps

GroundGPS

Superstar II

Control Laptop

ComputerPentium Core Duo

1 GB RAM, 2.16 GHz

Running Labview and ssh sessions

RS23219.2 kbps

Ethernet100 Mbps

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STARMAC Electronics System

WiFi802.11b

≤ 5 Mbps

ESC & MotorsPhoenix-25, Axi 2208/26

IMU3DMG-X1

76 or 100 Hz

RangerSRF08

13 Hz Altitude

GPSSuperstar II

10 Hz

I2C400 kbps

PPM100 Hz

UART19.2 kbps

RobostixAtmega128

Low level control

UART115 kbps

CF100 Mbps

Stereo CamVidere STOC

30 fps 320x240

Firewire480 Mbps

UART115 Kbps

LIDARURG-04LX

10 Hz ranges

RangerMini-AE

10-50 Hz Altitude

BeaconTracker/DTS

1 Hz

WiFi802.11g+

≤ 54 Mbps

USB 2480 Mbps

RS232115 kbps

Timing/Analog

Analog

RS232

UART

Stargate 1.0Intel PXA255

64MB RAM, 400MHz

Supervisor, GPS

PC/104Pentium M

1GB RAM, 1.8GHz

Est. & control

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Low Level Control

Event Driven Real-time execution based on

Known transmission / receipt rates Measurement of code chunk execution times

Fault Tolerant Communication

IMU RX

SG RX

SG TX

IMU TX

Main

(this is an asynchronous event)

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Information Seeking Target Localization

Applications

Decentralized Collision Avoidance

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COMMCLASS

GUI & Storage

Sensor Processing

Controller

Planner

Real TimeController

GPS

LIDAR

ROBO

GND

Estimator

GPSCalc

StateEstimator

GPS comm

Lidar comm

GND comm

Flyers Flyer comm

GUI (10 Hz)

Logging

EnviroLIDAR

Robo comm

signalserialUDP

Interfaces

Fcn call

all

all

any

“Flyer Brain” Architecture

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Questions?… and demo…