May06-17 – StratoLink Spacecraft Bus Design Review StratoLink Spacecraft Bus Senior Design Project May06-17 Adam Allison Robert Bond Hai Duong Alan Johnson David Johnson Client: Spacecraft Systems and Operations Lab Faculty Advisor: Prof. Mani Mina

May06-17 – StratoLink Spacecraft Bus Design Review Agenda Background Information Adam Allison Lithium Ion Batteries Robert Bond Battery Charger Hai Duong GPS Receiver David Johnson Communications Alan Johnson Conclusion Adam Allison

May06-17 – StratoLink Spacecraft Bus Design Review Definitions FAA – Federal Aviation Administration HABET – High Altitude Balloon Experiments in Technology NMEA – National Marine Electronics Association OEM – Original Equipment Manufacturer SSOL – Spacecraft Systems and Operations Laboratory

May06-17 – StratoLink Spacecraft Bus Design Review Background Project of Iowa State University SSOL Designed to reach near space altitudes Provides platform for high altitude experiments Highly successful HABET Project

May06-17 – StratoLink Spacecraft Bus Design Review Background What needs to be changed to accommodate those needs? Created as a variation of HABET Designed for informal educational groups and institutions Will collect temperature, position, and visual data Stores data on pre-existing data logger from HABET program Provides opportunity for students to learn about the flight procedures of a basic spacecraft More restrictive design constraints StratoLink Project

May06-17 – StratoLink Spacecraft Bus Design Review Background HABET StratoLink Uses amateur radio comm.  Satellite-based comm. Requires amateur radio license Capable of transmission after landing Payload limited by balloon restraints  Payload limited to 4 lbs FAA regulation Highest Altitude recorded ≈ 100,000 ft  Approx. up to 120,000 ft

May06-17 – StratoLink Spacecraft Bus Design Review System Overview Note: HOBO Data Logger and digital camera use present design from HABET

May06-17 – StratoLink Spacecraft Bus Design Review Lithium Ion Batteries 3.7 Volt Each 1200 mAh Rechargeable 34.2mm x 8.5mm x 48mm Built in Shutdown Separator Soldier Tabs included

May06-17 – StratoLink Spacecraft Bus Design Review Technical Specs Operating voltage: V Individual Weight: 38g per battery 4V cell weight: 152g +1g for soldier tabs Max Discharge Rate: 2.0A Rec. discharge voltage: V (avoid discharge below 2.5V) Recommended Temp: – º C

May06-17 – StratoLink Spacecraft Bus Design Review Charging info for Batteries Max Charge Current: 2.0A Charge time: 80% cap. in 1h 100% cap. in 2h Charge at const. voltage of 4.2V with current limited to A Rec. charging temp: 0-40 º C

May06-17 – StratoLink Spacecraft Bus Design Review Battery Charger Auto-off External from system Rechargeable 34.2mm x 8.5mm x 48mm Built in Shutdown Separator Soldier Tabs included

May06-17 – StratoLink Spacecraft Bus Design Review Battery Charger Input: AC V 50/60Hz Output: VDC Charging Current: 500mA Supported Types: Li-Ion larger than 400mAh

May06-17 – StratoLink Spacecraft Bus Design Review Battery Charger

May06-17 – StratoLink Spacecraft Bus Design Review Transceiver Purpose: Communicate with base without using amateur radio Services considered: Iridium Global satellite network Used for voice communication ORBCOMM US coverage Used for low data-rate data communications Overview

May06-17 – StratoLink Spacecraft Bus Design Review Transceiver Choosing a provider Considerations: Equipment needed Cost Weight Functionality Subscription/data costs Communication latency Reports of usage in the field ORBCOMM selected as the best solution

May06-17 – StratoLink Spacecraft Bus Design Review Transceiver Selected Transceiver Model: Stellar ST2500 Bought without case to reduce weight GPS Receiver – Garmin GPS-15H Antennas for each Tasks to be done: Program ST2500 Devise a shielding system for ST2500

May06-17 – StratoLink Spacecraft Bus Design Review Transceiver Technical Details System will be controlled by the ST2500’s onboard processor ST2500 will periodically take readings from the GPS and send data to the satellite ORBCOMM will forward the information via

May06-17 – StratoLink Spacecraft Bus Design Review GPS Receiver Design requirements: Lightweight Low Cost Functionality at 120,000 Ft. Operability at -85°C Purpose: To capture position from GPS satellites and relay it to spacecraft bus. Overview

May06-17 – StratoLink Spacecraft Bus Design Review Models considered: Input (VDC)Weight (g) Garmin GPS-15H Garmin GPS-15L Garmin GPS-18PC Garmin GPS-18LVC Researched Garmin, Thales, and Magellan OEM units GPS Receiver Receiver Selection

May06-17 – StratoLink Spacecraft Bus Design Review Garmin GPS-15H Receiver (courtesy Garmin International) Model: Garmin GPS-15H Technical Specifications: 12 Channel GPS Receiver Power Usage: 12VDC Input 8-40 VDC Output: RS232 NMEA 0183 and ASCII Antenna Connector: MCX Male Cost: $45.75 GPS Receiver Receiver Selection

May06-17 – StratoLink Spacecraft Bus Design Review Model: Garmin GA-27C Technical specifications: Connector: MCX Female Impedance: 50Ω Power gain: 28dB Cost: $47.14 GPS Receiver Antenna Selection

May06-17 – StratoLink Spacecraft Bus Design Review Current issues and risks Issues Communication with transceiver provider Finding proper antenna Risks Satellite transceiver may not be effective without shielding provided by the case Transceiver may not work at peak altitude ORBCOMM may not be reliable or quick enough to provide timely communication Temperature related equipment failure

May06-17 – StratoLink Spacecraft Bus Design Review Summary What we changed to meet the new Requirements HABET StratoLink Uses Radio Communication  New Satellite Package Amateur Radio license GPS, ORBCOMM Payload limited by balloon restrains  Payload limited to 4 lbs New Batteries requiring Charger