Development of a Fully Autonomous Micro Aerial Vehicle for Ground Traffic Surveillance

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Development of a Fully Autonomous Micro Aerial
Vehicle for Ground Traffic Surveillance
Aerospace Systems, University of Braunschweig
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Contents

• Introduction
• Theoretical Work
• The Hardware of Carolo
• Applications
• Current Status Outlook

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Introduction - What is an MAV ?

• definition according to DARPA
• semiautonomous aerial vehicle
• max. dimensions 15 x 15 x 15 cm
• max. mass 115 g (4 ounces)
• cost lt 1000
• additional requirements
• telemetry link to ground control(for remote
  control)
• real-time video link
• range 10 km
• cruising speed 50 km/h
• endurance 20 min - 60 min

Black Widow, Aerovironment Inc.
Entomopter, GeorgiaTec
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Introduction - The Project Carolo
Goal development of an autonomously operating
Micro Aerial Vehicle with dimensions as small
as possible
wing span 0.40 m mass 390 g cruising speed 18
m/s endurance 40 min range 45 km
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Theoretical Work
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Theoretical Work Overall Control Structure

• modeling of
• non-linear flight mechanics
• turbulent atmosphere

• sensor dynamics
• actuator dynamics

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Theoretical Work - Database
5 - dimensional parameter field
Wind Tunnel Readings
CX, CY, CZ, CL, CM, CN f(a, b, h, x, k)
Angle of Attack -10 lt a lt 40 Sideslip
-32 lt b lt 32 Elevator -15 lt h lt
15 Aileron -15 lt x lt 15 Flaps
-8 lt k lt 12
Calculated Damping Derivatives
Wind tunel test april 2002 at the Institute of
Fluid Dynamics, Technical University of
Braunschweig
Roll Damping CLp Pitch Damping CMq Yaw
Damping CNr
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Theoretical Work - Results
Simulation of the autopilot

• stable behavior, stationary accuracy
• oscillations due to
• sensor deadtime,
• GPS update rate
• missing curved flight compensation

• simulation with
• actuator dynamics
• sensor error models
• carolos control algorithms

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The Hardware of Carolo
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The Hardware of Carolo - Anatomy
telemetry
payload
on-board computer
sensors
propulsion system
actuators
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The Hardware of Carolo - Sensors

• receiver for Global Positioning System (GPS)
• atmospheric pressure sensor
• Inertial Measurement Unit (IMU)
• Micro-Electro-Mechanical Systems
• 3 angular rate sensors
• 3 linear acceleration sensors
• commercial-off-the-shelf components (COTS)
• in-flight sensor data fusion

MEMS-based 6-dof IMU
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The Hardware of Carolo - Sensor Calibration
comparison of MAV IMU data with Honeywell
LaserNav,test flight with the universitys
research aircraft DO128
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The Hardware of Carolo - Onboard Electronics
current autopilot hardware dimensions
75mm40mm38 mm mass 85
gr. including on-board computer gps
antenna 3 accelerometers 3 gyros
3-axis magnetometer 2 pressure sensors
GPRS
GPS
GPS
ACTUATORS
ACTUATORS
IMU
IMU
PROPULSION
PROPULSION
video camera 25 gr. (analog) telemetry
50 gr. (future)
PAYLOAD
PAYLOAD
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Applications
The MAV Carolo, wingspan 40 cm, mass 390 g
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Applications

• possible applications
• meteorology
• vertical profiles of temperature and humidity
• increase of spatial resolution by using multiple
  MAVs
• Live video transmission
• Police, border patrol, military applications
• Civil protection
• Ground traffic surveilance

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Ground Traffic Surveillance - Concept
Carolo
mission control
I n t e r n e t
GPRS / UMTS

• data analysis
• police, fire department
• ambulance
• accident investigation
• highway board department

mobile access of information
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Ground Traffic Surveillance - Image Sensor

• current analog video camera
• mass 25 g
• dedicated radio downlink
• live video stream
• short range 200 m
• under progress digital CMOS camera
• mass 30 g
• resolution 1.3 megapixel
• image transmission via telemetry link
• frame rate depends on telemetry data rate
• on-board image compression possible

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Ground Traffic Surveillance - Telemetry

• mobile cellular phone network
• infrastructure already available
• virtually unlimited range
• comparably low data rate requires image
  compression (e.g. JPEG2000)

type data rate
GSM 9.6 kbps
GPRS 28.8 kbps
UMTS 384 kbps
comparison of different standards for mobile
communication
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Ground Traffic Surveillance - Aerial Image Quality

• no compression
• field of view 510 m x 380 m
• image size 1024 x 768 pixel
• data size 2304 kbyte

high-resolution aerial picture, no compression
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Ground Traffic Surveillance - Aerial Image Quality

• JPEG2000 (rate 140)
• field of view 510 m x 380 m
• image size 1024 x 768 pixel
• data size 60 kbyte

high-resolution aerial picture, compression rate
140
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Ground Traffic Surveillance - Aerial Image Quality

• JPEG2000 (rate 140)
• field of view 160 m x 120 m
• image size 320 x 240 pixel
• data size 5.5 kbyte

low-resolution aerial picture, compression rate
140
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Ground Traffic Surveillance - Telemetry
type data rate time per hi-res. image time per lo-res. image
GSM 9.6 kbps 62.5 s 5.7 s
GPRS 28.8 kbps 20.8 s 1.9 s
UMTS 384 kbps 1.6 s 0.2 s
comparison of different standards for mobile
communication
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Ground Traffic Surveillance - Ground Control
ground control PC software, server-client-based
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Current Status Outlook
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Current Status - Towards Autonomous Flight
Altitude Controller - August 2003 -
Waypoint Navigation - September 2003 -

• circling during strong thermal activity
• DH lt 2m
• no optimized feedback gains

• succesful test of complete autopilot
• test platform model plane, span 1.5 m

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Outlook - Field Test

• cooperation with the German automobile club
  ADAC Niedersachsen/Sachsen-Anhalt
• agreement with local and federal authorities
• scheduled for Spring 2004

Carolo XL, wingspan 100 cm, mass 940 g
MAV Carolo, wingspan 40 cm, mass 390 g
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Carolos Flight, December 2002
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1st autonomous Flight, September 5th, 2003
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First European Micro Air Vehicle Conference and
Flight Competition     EMAV 2004 Braunschweig,
Germany  13 14 Juli 2004 organised by
the  German Institute of Navigation