CDIO-3 Product Concept

Requirements TeamOscar MurilloLeah SofferMaggie Sullivan

February 21, 2002

Mission Statement

Project Mission: Demonstrate the feasibility of electromagnetic control for formation flying satellites.Implications:

Demonstrate EM ControlFormation maneuvering vehicles

Functional Requirements 1:the Customer

Formation flyingStability in formationInterchangeable/replaceable modulesBoth autonomy and command response

EM control“Use magnets to generate the … restoring forces”“… will allow between 3 and 6 DoF EMFF”

Architectural notesHigh-permeability lightweight solenoid coresNecessary heat dissipationReaction wheels

Functional Requirements 2:the System

Top-Level: “The system shall…”Have interchangeable system modules Be tested on a realistic facilityMaintain relative separation/attitudeFollow steady course, predetermined or MC

SubsystemsPower Flight computerADS – Sensing ACS - ControlCommunication ProtectionTesting Integration

EM Trades

cc

w

PPmρα

µπ

β 00

43

=cc

w

s pPm

B ρπρα

ππµχω 3

6/50

50

23

=

slm ρπα 230 =

4

22

0)(

23

BniaF χπµ=

Angular Rate vs. Seperation Distance

0.00E+00

1.00E+01

2.00E+01

3.00E+01

4.00E+01

5.00E+01

6.00E+01

1 2 3 4 5

Seperation Distance (m)

An

gu

lar

Ra

te (

rad

/s

ec

)

Angular Rate

B-Field vs Core RadiusAngular Rate vs Core Radius

0.00E+00

1.00E-03

2.00E-03

3.00E-03

4.00E-03

5.00E-03

6.00E-03

7.00E-03

8.00E-03

9.00E-03

1.00E-02

0.01 0.02 0.03 0.04 0.05

Core Radius (m)

B-F

ield

(T

esa

)

0.00E+00

5.00E-01

1.00E+00

1.50E+00

2.00E+00

2.50E+00

3.00E+00

3.50E+00

4.00E+00

4.50E+00

An

gu

lar

Ra

te (

rad/

sec)

B-Field (Tesa)Angular Rate

Final Design

Inside spheres:•Reaction Wheels•Computer•Battery•Coil and Core•Transmitter/Receiver

Steel Core/Copper CoilMass = 5.26 kg

Separation =5mLength of core = 0.3mRadius of core =0.03mAngular Rate = 0.959

rad/secB-field = 3.20E-03

Force = 58.12 N

Operations Concept

Programmed response onlyGround-to-vehicle communication

User-initiated autonomous testsRealtime telemetry recording and storageEmergency interrupt sequence

Inter-vehicle communicationAutomated depth control

Pros and Cons

Advantages3D flightSimpler test carriageReduces danger of crash

DisadvantagesInstability of water environment

PolarityCurrents

Increased drag due to high density of test medium