The PEGASUS System - Aristotle University of Thessalonikinewton.ee.auth.gr/aerial_space/docs/IS_3.pdf · April 28, 2008-- A new Defense Advanced Research Projects Agency (DARPA) initiative,

1New Orleans, December 4th 2008 Confidential – © 2007, VITO NV – All rights reserved

The PEGASUS System :

using a HALE UAV to provide very high resolution images in real time

N. Lewyckyj – VITONew Orleans, December 4th 2008


VITO in a nutshell


• Autonomous public research company (shares 100 % owned by Flemish government)

• > 540 highly qualified researchers and technicians

• Bridge between scientific knowledge and industrial applications or government policy

• 3 main research fields : energy-materials-environment• Research projects on behalf of European (EC, ESA) and

National authorities (policy support)• Technology development in cooperation with industry • Annual budget : 101 M U$ (2007)

VITO : Flemish Institute for Technological Research



Remote sensing and earth observation processes

Remote sensing and image processing– Space- and airborne sensors – Advanced research and image processing– Production & distribution of derived products– Use of new technologies (UAVs)


Unmanned Aerial Vehicles (UAVs)

From EURO UVS report

Micro Flying Robot - Japan

Helios (Aerovironment/NASA, USA)

Sanswire (USA)

TU Delft de Delfly Micro PEGASUS


UAVs are complementary to conventional RS systems

• Complementary to satellites:– No orbital constraints -> very flexible trajectory ->higher update

rate– Higher spatial resolution and precision possible– Much cheaper -> easier to use more systems (constellations)– Requires less heavy infrastructure in operation– Can be very rapidly deployed– Easier change of the payload

• Complementary to manned aircrafts– Real time possible– Less constraints from air traffic control– Can be used in not optimal weather– Can hover above a limited ROI– Offer equivalent performances– Mostly much cheaper– No risk for pilots


UAV = Technology in evolution

1st W.W. RQ-5 Hunter > 3,000 hours(Iraq - 2003)


HALE UAV: the missing link in EO and DM

0.1-5 km Airborne sensors,

600-800 km Polar orbiting satellites

35400 km Geostationary satellites

Ground levelObs

erva

tion

altit

udes

5-10 km

12-30 km Stratospheric platforms, HALE-UAV

Medium altitude UAV

UAV


Pegasus is ProjectVery high resolution camera

Stratospheric UAV

Mobile GCS with satellite communication

Powerfull CDPC (grid computing)


The MERCATOR platform


– 32 kg, 18 m wingspan– Solar cells (day) + batteries (night)– Flying attitude : day 18 km - night 15 km– Rapid deployement possible– No need for important infrastructure– Ground launch (propellors) or using balloon– Operationnal speed ~ 20 m/s– Endurance: weeks to months– Data downlink (170 Km LoS)

Constraint: – max. 2kg payload– 50W over day– clearance

Mercator-1 principal characteristics



Zephyr in White Sands

http://www.newscientist.com/blog/technology/labels/UAVs.html


Zephyr : endurance WR (> 80 hours)


Performances of HAP increase continuously

2008

2007

2006

2005

0

10000

20000

30000

40000

50000

60000

70000

0 20 40 60 80 100

endurance (hours)Fly

ing

alt

itu

de (

ft)


The MEDUSA camera


MEDUSA instrument: specifications

• Ground sampling distance: 30 cm (@ 18 km )• Wavelength range: 400 – 650 nm (RGB)• 2 CMOS sensor 10.000 x 1.200 pixels• Swath width: 3000 m• SNR = 100 @ 8:00 am equinox• 60% forward overlap between images• Near-realtime data delivery


Constraints• Mounted on front of UAV fuselage• Mass: 2-3 kg• Available power: 50 W (during daytime)• Pressure down to 60 mbar• Base temperature down to -70°C• Large temperature variations• Volume: 1m length, 12 cm diameter• Attitude behavior of the platform (motion blurring)


baffles

Passive compensator

4 lens tube

Mirror Entrance window

http://medusa.vgt.vito.be/

• Focal Plane assembly• Data Command & handling Unit• IMU• S-band transmitter• GPS receiver• Power regulator

MEDUSA instrument: layout


First geometric calibration tests(panchrom. COTS sensor)

Calibration target at ~ 100 feet• Point diameter 2 mm• Spacing 2.2 cm


First outdoor tests

Object MEDUSA image

Distance camera target ~ 230 feet


The Mobile Ground Control station


• Mobile (fits in standard size container)• Control of UAV + • Reception telemetry (GPS, IMU)• Reception payload data • Data archiving (2TB)• Transmission to VITO via satellite comm.• Control range up to 170 km• Autonomous (power generators)• Includes an autonomous µ-PAF

A mobile GCS offers high flexibility


Reprogrammable flight planning

• Flight planning up to 1000 way points• Meteorological data on line => flight envelop• Warning system “out of range”• Possible on-line reprogramming of the flight pattern


The Central Data Processing Center


Central Data Processing Center

– Archiving of all data (database)– Actually ~60 TB available– HDF5 self describing forma– Automatic processing data– Up to level 4 products on request– Parallel processing (real time)– Web services and applications


The PEGASUS project



R ~ swath

GSD = 0.3 m

R ~ 3 km

Update ~ 8.2 min

Coverage ~ 28.3 km²

R ~ 0.5 swath

GSD = 0.3 m

R ~ 2.7 km

Update ~ 1.6 min

Coverage ~ 5.7 km²

Coverage using M1+ Medusa


R ~ 0.5 swath

Update ~ 1 min

Coverage ~ 72 km²

Update ~ 25 min

Coverage ~ 314 km²

R ~ swath

Pegasus with GSD = 1 m Swath = 10 km

Update ~ 4.7 hours

Coverage ~ 2500 km²

50

km

50 km


Pegasus is dedicated to local and regional applications

• Low speed (~ 20 m / s) = > limited coverage

• Control from the GCS limited to 170 km radius (mobile CGS only between events )

• Very high resolution = > limited swath (3 km @ 30 cm GSD)

• No storage on board


Coverage of Europe

• Annual coverage for research at 20 cm ~ 30 HAPs• Operationnal annual coverage at 30 cm ~ 52 HAPs

(including dedicated HAPs, max. coverage 150.000 km²)• 30-50 fixed GCS + some ‘mobile’ GCSs• One GCS can command more than one HAP• Command of one HAP can be passed from one CGS to

another• DPC : One central unit (one per country ?)• Different instruments (VIS, IR, SAR,…)


The PEGASUS advantages• Low speed => very flexible trajectories• Autonomous mobile GCS with rapid deployment• Long Endurance : days to weeks continuously• No need for airport infrastructure• Automatic flight planning with possible update• Equipped with a high resolution RGB digital camera• Instrument recovery (test/maintenance/upgrade)• Data in near real-time available via protected internet• Flying above ATC• Large part of automatic image processing (QA/QC)• Continu acquisition (database) + dedicated missions


• Limited in payload weight (2 kg => 5-10 kg)

• Limited in available power (50 W, day time)

• Limited speed

• Regulatory problems (clerance e.g. OSIRIS project)

The PEGASUS drawbacks


How expensive are RS systems?

• Satellite imagery:IKONOS “prioritary” : ~ € 20.000 for orthorectified image of 17 x17 km²

• Airborne systems: ~ € 30.000 to € 50.000 (incl. stand-by)

• Prototype Pegasus (HAP + GCS + payload + software) : 16 M€

• Production Pegasus : estimated to ~ 8-10 M€(Global observer – Aerovironment USA: ~ 20 MU$, including 2 GCS)

• Small low altitude UAVsAirplane : up to 20 k€Helicopters (incl. autonomous flight system) ~ 50 - 1000 k€


Some conclusionsand trends


Satellites

Manned systems

Flying Altitude

Global coverageLow-Medium resolution

HAPsLocal-Regional coverage

High resolution

Local coverageHigh resolution

New sensors (hyper)

Small UAVs Local coverageVery high resolution


The “perfect” sensor system do not exist

• Only combination of systems provides adequate information, especially for real-time issues

• Interoperability is therefore a key issue

• Selection of information is crucial (avoid data overflow)


Some trends are

• Standardization (e.g. OGC for geographic information)• Development of smart sensors• Miniaturization and cost lowering• Development of sensor networks/constellations• Higher resolution => more data• Data fusion (all type) will get more and more important• Processing will be more and more automated• Data processing in limited specialized centers

-> communication is very important• Concerning RS, UAV’s will play a major role during the

next decade


Pegasus :a revolution or just a normal evolution ?


The Vulture program From http://dsc.discovery.com/news/2008/04/28/vulture-plane.html

Extra Wide Plane to Stay Aloft for Five Years Eric Bland, Discovery News April 28, 2008 -- A new Defense Advanced Research Projects Agency (DARPA) initiative, codenamed Vulture, aims to create a plane that can fly continuously for five years.


http://news.bbc.co.uk/2/hi/science/nature/6916309.stm

Mercator scale model (2003)


Thank you for your attention

http://www.vito.behttp://www.pegasus4europe.com

Documents

The PEGASUS System - Aristotle University of Thessalonikinewton.ee.auth.gr/aerial_space/docs/IS_3.pdf · April 28, 2008-- A new Defense Advanced Research Projects Agency (DARPA) initiative,