Simplified Femto-satellite Operations

for Disaster Mangement Missions

Joshua Tristancho

UPC Barcelona Tech - SPAIN

tristancho@gmail.com

Jordi L. Gutiérrez

Applied Physics department (UPC)

Jordi.gutierrez@upc.edu

October 3rd, 201263rd International Astronautical Congress, Naples, Italy. 10IAC-12-B4.3.12

2

Index

1. Introduction

2. Task analysis for DM

3. Simplified method for femtosat

4. Simulation of a mission

5. Conclusions

License:

Team FREDNET

Creative Commons

http://creativecommons.org/licenses/by-nc-sa/2.5/es/deed.en

Inde

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Introduction (I) – Space Payload Paradigm

Femto-Satellite: New technological limit (<100 grams) The lower the satellite mass, the lower the launcher size

and so, the lower the cost. Swarms. Constellations Very-Low Earth Orbit, short mission life (few weeks) and

more reusable orbits

1. I

ntro

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Introduction (II) – Femto-satellite specs.

Minimal number of subsystems:High gain and sensitivity modem Microstrip antenna

Attitude control (Magnetorquers) High resolution payload camera

Passive thermal control Electrical power management

Payload separated from the satellite LiPoly battery source

High accuracy attitude and position determination

Optimized on-board computer (Arduino like)

TECHNOLOGIES

- Use of MEMS

- SMD technology

- High G load tolerant

Femto-satellite protoype without

battery.(Less than 8 grams)

Source: www.wikisat.org

1. I

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Introduction (III)

Types of disasters that a femto-satellite can address:– Earthquake Changes in the first week– Tsunami Short duration (Except Drought)– Drought Tens of meters per pixel– Cyclone Not very high resolution– Fire– Flood– Landslide– Volcano

1. I

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Introduction (IV)

The emergency cycle by Lew Sian Many launch stations aruound the world in the

Preparedness phase Femto-satellites will be used mainly in the Response

phase. First hours are critical for the first responders

1. I

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LEO satellite tasks for Disaster Management

Earth Observation– Acquire images from the Disaster Area– Send this images to Decision Makers

Data Relay– Provide basic communications to First Responders

2. T

ask

anal

ysis

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DM

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Initial hypotheses (I)

Use of femto-satellite swarm dedicated a single mission

Each femto-satellite will perform a revisit every day

Aerodynamic drag - Femto-satellite life 1 or 2 weeks

Femto-satellite horizon is about 2,000 km (Very-LEO)

Femto-satellite transit could have an angle (Corrections)

2. T

ask

anal

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DM

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Initial hypotheses (II)

Limited energy – Only use energy when– Recording– Communications– Attitude corrections

No solar panels to recharge the battery – Energy budget

2. T

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anal

ysis

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DM

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Initial hypotheses (III)

High power wireless modem. No huge ground station required

Two download modes:– Slow long range:

200 km footprint– Fast short range:

50 km footprint

Information is not

encrypted (Global interest)2. T

ask

anal

ysis

for

DM

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Agents

Interest Point = First Responders Ground Stations = Decision Makers

Simplified List:– First coordinate point is the Disaster Area Epicenter– The rest of coordinate points are Ground Stations

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DM

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Ground Station policy (I)

No priority between Ground Stations

Nearest Ground Station will be kept until it is lost

A change between station is a waste of time

Ground Stations closer than 1,000 km between them are useless

Ground Stations near the Disaster area are useless. The priority is for the First Responders2.

Tas

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Ground Station policy (II)

The less number of Ground Stations the higher life due to both– Battery duration (No solar panels) and– in-orbit time (Aerodynamic drag)

Share the info through a single agency– i.e. UN-SPIDER– Less femto-satellite consumption– Larger life

2. T

ask

anal

ysis

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DM

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The Simplified Method (I)

List of coordinates (Up to eight coordinates)

First coordinate is the Interest Point and it has absolute priority. First Responder are there by definition

The rest of coordinates are ground stations without priority. Decision Makers or other agents3.

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The Simplified Method (II)

Aerodynamic attitude only

abandoned when a coordinate

should be follow

The femto-satellite broadcast the information when there is a coordinate to follow (200 km footprint)

It tries to establish a fast download (50 km footprint)

If succeeds, a new coordinate list could be uploaded by the Ground Station if password is provided3.

Sim

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The Simplified Method (III)

The femto-satellite always follows the same Ground Station until it is not in view, then follows the nearest Ground Station if not, aerodynamic attitude is kept

The only exception to the previous statement is when the Interest Point coordinate appears; then aerodynamic attitude or previous coordinate is abandoned

It is possible to acquire and establish a link at the same time when First Responder has a Wireless equipment that works as a Ground Station (Optimum case)

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The case of Sri Lanka – Tsunami impact (I)

00:58:53, 26 Dec 2004 (UTC) Magnitude 9.1 to 9.3 Mw Epicenter 3.316 N, 95.854 E Depth 30 km (19 mi) 250,000 deaths

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The case of Sri Lanka – Tsunami impact (II)4.

Sim

ulat

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of a

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The case of Sri Lanka – Tsunami impact (II)4.

Sim

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of a

mis

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The case of Sri Lanka – Tsunami impact (II)4.

Sim

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of a

mis

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The case of Sri Lanka – Tsunami impact (III)

A single femto-satellite launched few hours after the disaster

Coordinate List based on two points– Matara

(Sri Lanka)– Mas Palomas

(Spain)

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http://4.bp.blogspot.com/-T3kYiRiDed0/TyZmUR5zlJI/AAAAAAAAG7w/P90Nene0IcY/s1600/tsunami_sri_lanka.gif

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The case of Sri Lanka – Tsunami impact (IV)

Femto-satellite provides coverage during 8 days

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The case of Sri Lanka – Tsunami impact (V)

2 h and 24 minutes after, First Responders have images

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The case of Sri Lanka – Tsunami impact (VI)

8 contacts with First Responders (One every day) 30 contacts with Mas Palomas Ground Station

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Conclusions

Following the Space Payload Paradigm, swarm of femto-satellites will be sent with a low-cost. It will be feasible thanks to a huge reduction of mass through a simple design and operation

Space responsive femto-satellites will be dedicated to Disaster Management (DM) mainly in the Responsive phase. First hours are critical for the First Responders

Real-time pictures are sent to the First Responders via wireless. No large infrastructure is required

The operation of each femto-satellite is simplified using a List of Coordinates. The first is the Interest Point. The rest are scheduled downloads for Decision Makers or others agents

5. C

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Thanks for your attention!

tristancho@gmail.com

This work has been supported by the MITYC under the contract reference TSI-020100-2010-138 as a part of the grant AVANZA competitividad I+D+I 2010