project bellerophon april 17, 2008 avionics

AvionicsAAE 450 Spring 2008

Project BellerophonApril 17, 2008

Avionics

Overview AvionicsTelecommunicati

onsVehicle

Antennas

Data Chann

els

Tracking

Ground

Antennas

Data Chann

els

Data Proces

sing

Flight ControlData Processing

Inputs

Sensors

OutputsControls

Power Systems

Source

Supply

AvionicsAAE 450 Spring 2008 1

Electronic Parts: Component RatingCommercial

Class B

Class S

Commercial Requirements Class S RequirementsInfinite production lot size Built one at a time

No burn-in testing Extended burn-in time (up to 240 hours)

No detailed failure analysis Extended failure analysis

No life testing 1,000 hour life test on every lot

No traceability Traceable to the raw materials

> 1% failure per 1000 hours allowed 0.0001% failures per 1000 hours allowed

1 NASA Electronics Parts Assurance Group


Telecom Analysis: Doppler ShiftFrequency Shift due to Doppler Effect

0 2000 4000 6000 8000 10000 12000 14000 16000 180000

20

40

60

80

100

120

140

160

180

200

Vehicle Velocity (m/s)

Freq

uenc

y S

hift

(kH

z)

401 MHz1.45 GHz2.2 GHz3.0 GHz


Telecom Analysis: Data Rate

0 1 2 3 4 5 6 7 8 9

x 107

0

5

10

15

20

25

Data Rate (bps)

Link

Mar

gin

(dB

)

401 MHz1.45 GHz2.2 GHz3.0 GHz3 dB Margin

Change in Link Margin due to Data Rate


Telecom Analysis: Path Length

0 1000 2000 3000 4000 5000 6000 7000 80000

5

10

15

20

25

Path Length (km)

Link

Mar

gin

(dB

)

401 MHz1.45 GHz2.2 GHz3.0 GHz3 dB Margin

Change in Link Margin due to Signal Path Length


Telecom Design: Vehicle Link BudgetItem Value Units frequency 401 MHz transmitter power 5 Watts transmit antenna beamwidth 60 deg transmit antenna diameter 0.87 m equiv isotropic radiated power 12.3 dB-W propagation path length 5,000 km receive antenna diameter 10 m receive antenna beamwidth 5.24 deg data rate 9,600 bps signal to noise ratio 50.82 dB carrier to noise density ratio 90.64 dB-Hz bit error rate 0.00001 --- implementation loss -2 dB final margin 39.20 dB

Simplified Link Budget

Minimum Margin:3 dB

Vehicle Margin:39.2 dB


Range Safety Officer (RSO)– An individual who is responsible for the remote destruction and

consequent flight termination of the launch vehicle should it be deemed a hazard.

RSO Responsibilities– Evaluate the launch vehicle design as well as oversee the manufacturing

process. – Monitors the launch vehicle and environmental conditions prior to

launch. – Monitors and tracks the launch vehicle during flight.

Hiring– Budget $1,700 per launch, assuming a 5 day period.

Range Safety: Personnel


Flight Corridor– An imaginary zone that exists in a space above the launch range.

Application– Implemented so that if the launch vehicle where to experience a failure

during flight, the vehicle will fall to the ground in an uninhabited area.

Termination– The launch vehicle must be destroyed if it flies outside the

predetermined flight corridor.

Range Safety: Flight Corridor


Non-Space-Rated Sensors

Sensor Type Part Number Manufacturer Unit PriceThermal TS3-85 Cantherm $10.29

Pressure 2000260 Measurement Specialties Inc.

$104.06

Flow 26616 Gems Sensors, Inc. $154.95

Force FSS1500NSRHoneywell Sensing and Control $46.56


Space-Rated Sensors

Sensor Type Part Number ManufacturerUnit Price

Thermal S311-641/04Honeywell Sensing and Control

$800

Pressure PPTRHoneywell Sensing and Control

$970


Sensor Reliability Analysis: ThermalSensor Company Accuracy Reliability

270 Space Series Honeywell Aerospace

±2.8°C 100,000 Cycles

MCP9700/9700A (non-space-rated)

Microchip ±2°C none

AS-TE (space-rated)

Fluid Components International

± 0.3° C 200,000+ Hours

Various (space-rated)

Measurement Specialties

±0.01˚C 3500 cycles(can be specified)

This table details the reasons for differences in cost.


Power Supply: Power Budget

Vehicle Flight Time Balloon Rise Time

Vehicle System

Percent of Operating

PowerPower

(W)

Energy Consumption

(Wh)Mass

(kg)Power

(W)

Energy Consumption

(Wh)Mass

(kg)Payload 5 10 1.04 0.01 10 30.00 0.27Propulsion 35 70 7.25 0.07 0 0.00 0.00Attitude Control 15 30 3.11 0.03 0 0.00 0.00Communications 10 20 2.07 0.02 20 60.00 0.55Command and Data Handling 5 10 1.04 0.01 10 30.00 0.27

Thermal 5 10 1.04 0.01 0 0.00 0.00Power Management 25 50 5.18 0.05 10 30.00 0.27

Total 100 200 20.72 0.19 50 150.00 1.361.5 Safety Factor 300 31.08 0.28 75 225 2.05

200g Payload Case, Silver Zinc Battery, Balloon Launch


Power Supply: Battery SelectionLiCF Li SOCl2 AgZn

Watt-Hours/Kilogram 130 185 110

Watt-Hours/Liter 160 240 200

Discharge Rate Low Moderate High

Failure Tolerance Low Low High

Cell Voltage 2.95V 3.1V 1.5V

Experience Level High Moderate High

Costs Low Low Low


Power Supply: AgZn BatteryAgZn Benefits

Can charge 4 to 6 times in case of scrub

Capable of controlling gimballing, ignition, and range safety subsystems

Silver Zinc (AgZn)Battery Property ValueWeight (kg) 2.3 - 4.5 Volts (V) 1.6 - 1.85 Rated Capacity (Ah) .8 - 800Specific Energy (Whr/kg) 55 - 286

Energy density (Whr/l) 55 - 262

1http://www.eaglepicher.com/


Power Supply: Batteries

Estimate Cost: < $10,000 Weight: 2.3-4.5 kg

Battery Weight Wh/kg CostSilver-Zinc (AgZn) 2.3-4.5 kg 110 ~$10,000

Lithium-Monofluoride (Li/CF)

2.3-4.5 kg 130 --------

Lithium/Thionyl Chloride (Li/SoCl2)

2.3-4.5 kg 185 --------


Installation CostPrimary Contractor: Aircraft Electrician

Median Salary1 $40,984.00Work Days per Year 240Income Per Day $170.77Income Per Hour $21.35Billing Rate Per Hour $32.02

At four weeks of billable workInstallation Cost: $7,172.20

1 Salary data from www.salary.com


Telecom: Failure AnalysisSources

ofFailure

Reliability FactorsFor a low complexity system with redundancy1:

Part Class ReliabilityClass B: 98.75%Class S: 99.87%

Assumptions - Simple system - Low radiation dose - Reliability based on a five year mission plan

1 Wertz, 404.


First Stage: 6.024 kg total (safety factor=1.2)-wiring: 2kg-sensors 1.02kg-battery 2kg

Second Stage: 30.2664 kg total (safety factor=1.2)

-Telecom: 10 kg -CPU: 0.85 kg-Sensors: 1.02 kg -Range Safety: 9.23 kg-Wiring: 2 kg -IMU: 0.122 kg

-Battery: 2kg Third Stage: 1.2 kg total (safety

factor=1.2)-Wiring: 1 kg

Mass Budget


Launch lock (US Patent 6508437) Motorized release Explosive Bolt/Spring sequence1 Explosive/Slingshot Sequence

1(Professor Filmer), (International Reference Guide to Space Launch Systems pg 296)

Payload: Launching Options


Assumptions Made– The Earth is spherical in shape.– The area where the signal intercepts the Earth is circular.– Neglect any antenna mounting errors or design issues.– Neglect any atmospheric anomalies which may refract the signal.– The signal propagation from a cluster of directional antennas can

be estimated using a omnidirectional antenna.– The signal propagation from an omnidirectional antenna is

spherical in shape.

Signal Projection: Assumptions


1Professor Filmer, Purdue University School of Aeronautics and Astronautics

Approximate Ground Equipment Costs1

Radio ($1,200)Antennas ($500)

Computer ($2,000)Misc ($500)

Total: $4,200

Example Case: Small Payload Launch Vehicle

LV Ground Track Balloon Ground Track236.09 km 120.74 km

Mean Propagation Radius4,995.4 km

Launch Vehicle Tracking


Avionics: Cost BudgetUnit Costs Wiring - Materials $ 500

- Installation $ 7,500 CPU $ 10,000 IMU $ 15,000 Sensors (500 each) $ 8,000 Battery $ 10,000 Range Safety $ 20,000 Ground Tracking $ 24,000 Total $ 95,000


project bellerophon april 17, 2008 avionics

Documents

launch range

launch vehicle design

terminationthe launch

telecom analysis

link margin

data rate avionicsaae

signal path length avionicsaae

flight corridoravionicsaae