High Altitude Balloon Payload Design Project

Mission Objective "To collect data from a custom radiation sensor in a high altitude environment." -Detects location of ionizing radiation strikes -Tested with variety of radiation sources -Ready for testing in representative environment

Design Team:  Laurie Smoot (EE)  Tiffany Heetderks (EE)  Stephani Schielke (CS)  Rachael Luhr (CS)  Lizi Clem (MET)  Katie Schipf (ME) Advisors:  Dr. Brock J. LaMeres - Electrical & Computer Engineering  Dr. Angela Des Jardins - Montana Space Grant Consortium  Hunter Lloyd - Computer Science  Robb Larson - Mechanical & Industrial Engineering Sponsor :  NASA Budget: $450 Schedule: 8 Weeks 6/6/11 - 7/29/11

Level 1 Requirements Functional Requirements:  Log and store data from a custom radiation sensor while the sensor is flown on a high altitude balloon.  Power the sensor and computer system  Protect the system from environmental elements during flight  Protect the system from impact upon landing  Self-monitor power system

Level 1 Requirements Continued Performance Requirements:  Log data from sensor to provide sufficient information about the radiation environment  Provide power for the duration of mission  Store data on non-volatile memory that can be retrieved regardless of power failure  Preserve data in the worst-case landing scenario (100k feet free fall, water, fire, animal)  Be able to log power failures for sufficient analysis

Level 1 Requirements Continued Physical Requirements: Must not exceed 2.72 kg Must fit in a 15 cm x 15 cm x 30 cm box. Must mechanically and electrically interface to BOREALIS system with HASP considerations Must be able to withstand temperatures from -60°C to +40°C (-60°C to 60°C for HASP)

Level 1 Requirements Continued Reliability Requirements:  Must be able to be launched one time

System Architecture Computer Subsystem Electrical Subsystem Mechanical Subsystem

-Log Data  Log once every microsecond  Log for a duration of 4 hours -Specifications  Number of channels >32 digital 1 analog Computer Design Criteria

Concept Generation Idea #1 Arduino Mega 2560  54 digital GPIOs  16 MHz clock speed  Operating Voltage: 5V  x x 15.29mm  SRAM: 8KB; Flash: 256KB  Weight: 34.9g  Total Cost: $69.00 Computer System

Concept Generation Idea #2 Emartee Nano Mega 2560  70 digital GPIOs  16 MHz clock speed  Operating Voltage: 5V  71 x 53 x 11.3mm  SRAM: 8KB; Flash: 256KB  Total Cost: $55.00 Computer System

Concept Generation Idea #3 LeafLabs Maple  39 digital GPIOs  72 MHz clock speed  Operating Voltage: 3.3V  x x 14mm  SRAM: 20KB; Flash: 64KB  Weight: 17g  Total Cost: $59.00 Computer System

Preliminary Analysis  Number of digital I/O pins > 32 for radiation sensor interface  Non-volatile Storage o SD Card Write Speed: 17.8 MB/s o USB Flash Drive Write Speed: 5.5 MB/s  Data Logger Shield o Independent power supply to monitor electrical subsystem with time stamps  Voltage 3.3V o More compatible with power system, radiation sensor and Data Logger  72MHz clock speed allows more Write instructions per cycle Computer System

Design Selection: Decision Matrix Final Selection: LeafLabs Maple Adafruit Data Logging Shield Industrial-Grade Wide Temperature SD Card Computer System Importance Scale: 1-5 Rating Scale: 1-10 (One being the lowest Score)

-Provide Power  Computer System (~0.5 W)  Sensor (~2 W) -Specifications  Voltage (+/- 3.3V and/or +5V)  Lifetime (4 hours)  Temperature (-40 to +40 C) Electrical Design Criteria

Concept Generation Idea #1- DC/DC Converter SUS10123R3/SUS  Input Voltage Range: 9-18V  Output Voltage: 3.3V or 5V  Maximum Output Current: 2.6A or 2 A  Efficiency: 82% or 85%  Temperature Range: -40 ° C to – 85 ° C  Price: $29 Electrical System

Concept Generation Idea #2 – DC/DC Converter 1003S12HN/1005S12HN  Input Voltage Range: 9-18 V  Output Voltage: 3.3 V or 5 V  Maximum Output Current: 2.4 A or 2 A  Weight: 16g  Efficiency: 78% or 82%  Temperature Range:- 40 ° C to +105 ° C  Price: $27 Electrical System

Concept Generation Idea #3 – DC/DC Converter MJWI10-24S033/MJWI10-24S05  Input Voltage Range: 9-36 V  Output Voltage: 3.3 V or 5 V  Maximum Output Current: 2.2 A or 2 A  Weight: 15g  Efficiency: 86% or 84%  Temperature Range: -40 ° C to +60 ° C  Price: $21 Electrical System

Concept Generation Electrical System Idea #4 – DC/DC Converter CC6-0503SF-E  Input Voltage Range: 4.5V – 9V  Output Voltage: 3.3V  Maximum Output Current: 1.2A  Weight: 15g  Efficiency: 76%  Temperature Range: -40 ° C to +85 ° C  Price: $16

Idea #1 --- Battery Selection Energizer Ultimate Lithium  Output Voltage – 1.5V  Max Output Current – 2 A  Temperature Range – -40C to 60C  Weight – 14.5 g  Cost – ~$3/battery Concept Generation Electrical System

Idea #2 --- Battery Selection Energizer Advanced Lithium  Output Voltage – 1.5V  Max Output Current – 1.5A  Temperature Range – -40C to 60C  Weight – 14.5 g  Cost – ~$2/battery Concept Generation Electrical System

Idea #3 --- Battery Selection UltraFire Li-Ion Rechargeable  Ouput Voltage – 3.6V  Max Ouput Current – 0.9A  Temperature Range – -40C to 60C  Weight – 44.5 g  Cost – ~$7/battery and ~ $17/charger Concept Generation Electrical System

Preliminary Analysis Power = IV [W] Power = (I in )(V in ) = (I out )(V out )/(Efficiency) Output Voltage: -3.3V/+3.3V Output Current: Sensor: +3.3V A -3.3V A Computer: 0.15A Input Voltage: -12V/+12V Electrical System

Design Selection: Decision Matrix Electrical System Design Selection: Decision Matrix Electrical System Importance Scale: 1-5 Rating Scale: 1-10 (One being the lowest Score) Final Selection:  Energizer Advanced Lithium

Design Selection: Decision Matrix Final Selection:  CC6-0503SF-E DC\DC Converter Electrical System Importance Scale: 1-5 Rating Scale: 1-10 (One being the lowest Score)

Mechanical Design Criteria -Protection Temperature (-60°C to +60°C) Wind Impact (protect SD card) -Fit to HASP constraints -Packaging (everything fits in the box) -Specifications Weight (2.72 kg) Dimensions (15x15x30 cm)

Concept Generation Materials evaluated to meet thermal requirements:  Polystyrene - Extended  Polystyrene - Extruded  Polyisocyanurate (Foam board used by BOREALIS)  Thermasheath 3 Insulation Materials evaluated for added durability:  Plexiglass shell  Fiberglass cloth with resin Mechanical System MSU!

Concept Generation Cont. Mechanical System Material Properties Table: Thickness, Thermal Resistance, Mass, and Cost

Preliminary Analysis: Thermal 2D Heat Transfer Analysis Concepts: Conductive Heat Transfer: Q (W) = kA Δ T/X k = thermal conductivity (W/mK) A = cross sectional area (m 2 ) dT = change in temperature (K) X = thickness of the material (m) Thermal Resistance (R) = X/k therefore; Q = Δ T/R Mechanical System

Preliminary Analysis Cont: Thermal 3D heat transfer analysis: For a rough estimate, a shape factor (S) is used to estimate the heat transfer through all sides of the payload. Resulting in the equation: For internal temperature (Ti): Mechanical System Shape factor for square channel of length L* *Table 4.1in Intro to Heat Transfer by Incropera

Preliminary Analysis Cont: Thermal Analysis to determine insulating material for payload Computer and Electrical operating range: -40 ° C to 85 ° C (Inside temperature) Atmosphere temperature conditions: -60 ° C to 40 ° C (Outside temperature) Mechanical System

Alternative Evaluation Alternative #1: To meet temperature AND durability Polyisocyanurate Rigid Foam Insulated Sheathing  Standard insulating foam used for BOREALIS flights  R-value of K*m2/W o Capable of maintaining internal operation temp  Cost: $11.00  Weight: 0.23 kg Mechanical System

Alternative Evaluation Cont. Alternative #2: To meet temperature AND durability Polyisocyanurate Foam with Plexiglass casing  Increased durability  R-value of 1.15 K*m2/W o Capable of maintaining internal operation temp  Cost: $20.00  Weight: 0.761kg Mechanical System

Alternative Evaluation Cont. Alternative #3: To meet temperature AND durability Polyisocyanurate Rigid Foam Insulated Sheathing with Fiberglass Fabric and Resin  Increased durability protects foam from damage and able to reuse payload.  Waterproof  R-value of K*m2/W o Capable of maintaining internal operation temp  Cost: $33.00  Weight: kg Mechanical System

Design Selection Final Section: Polyisocyanurate Rigid Foam Insulated Sheathing Fiberglass Fabric and Resin Mechanical System Importance Scale: 1-5 Rating Scale: 1-10 (One being the lowest Score)

Selection of the Best Idea LeafLabs Maple Adafruit Data Logging Shield Industrial-Grade Wide-Temperature SD Card CC6-0503SF-E DC/DC Converter Energizer Advanced Lithium Batteries Polyisocyanurate Rigid Foam Fiberglass fabric and Resin MechanicalElectricalComputer

Final Design Selection Total Mass of the Payload Sensor = 83.5 grams Computer System:  Data Logging Shield = 22 grams  LeafLabs Maple = 17 grams Electrical System:  Battery Box (2) = 72 grams  Batteries (16) = 232 grams  DC-DC Converter (2) = 32 grams  Protoboard (1) = 37.2 grams Mechanical System:  Payload = grams  Inner materials = 150 grams  Assembly materials = 200 grams TOTAL: grams kg

Click to edit the outline text format Second Outline Level  Third Outline Level Fourth Outline Level  Fifth Outline Level  Sixth Outline Level  Seventh Outline Level  Eighth Outline Level  Ninth Outline LevelClick to edit Master text styles  Second level  Third level  Fourth level » Fifth level Budget ($450) Computer System:  Data Logger Shield: $24  LeafLabs Maple:$60  Rugged SD Card: $53  Total: $137 Electrical System:  DC/DC Converter: $40  Lithium Batteries: $70  Battery Box: $6  Protoboard: $3  Wires: $7  Total: $126 Mechanical System:  Box Material: $33  Extra Inner Insulation: $15  Assembly Materials: $20  Total: $68 Grand Total $ $331 Approximately $119 Under Budget (for preliminary design considerations)

Schedule

HASP vs. BOREALIS HASPBOREALIS Altitude126,000 ft100,000 ft Flight Time15-20 hours (stays at altitude) 100 min. Power SupplySupplied by HASP-payload plugs into their main supply Self-Powered Temperature Range-60 to +60°C *Absorbs more heat from sun while sitting at altitude -60 to +40°C

HASP Design Considerations: Electrical System:  Would need to consider and design for a 30V input.  Design a circuit that would produce a positive and a negative input voltage.  Choose a DC to DC switched-mode converter that would operate for new input voltage. Mechanical System:  Overheating in the sun may cause damage to the electronics since the balloon will be at altitude for an extended period of time. o Add heat sink to actively cool electronic system o Change color and reflectivity of the payload to decrease the absorbance and change emissivity in order to deflect some of the sun's rays.

Questions? Thank you!