Review data sheets for all components in thermal control subsystem to confirm that they can survive in temperatures from -20C to +50C while non operational.
All thermal components meet the worst-case hot and cold temperature limits. https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
Review data sheets and design documents for all components to calculate the total weight of components and confirm that it does not exceed 100 g.
Total mass for thermal components is 70.1 g https://docs.google.com/spreadsheets/d/1xTSUuH5_orqI86fC1yxH_xGrJsvVEi-rlDF5wRiUS_g/edit#gid=1301516532
Review data sheets and design documents for all components to confirm all components are the correct size to fit within a 3U cubesat.
The power working volume can be seen here: https://sites.google.com/site/manitobasat1/subsystems/mechanical-structural/structural-icd-overview#h.p_quRgGKIEcfiu
All components are smaller than 10 x 10 cm https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG, which fits into the working volume outlined in the Power Modula Working Volume-UMS 0080 section.
Review data sheets to ensure no vibration sensitive components are included in the design
No vibration concerns for any thermal parts- all components will be epoxied in place with space and vibration proven epoxy. Heaters and thermistors have no moving parts. Thermostats selected are bimetallic disk thermostats (disc moves within the cavity). Thermostats selected are high-reliability, meant for extreme environments and therefore not expected to be sensitive to vibration.
A vibration test was also performed on the thermostat to verify is is not vibration sensitive. https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-testing-phase-c#h.eypxb3w0x523
Perform simulations in NX SST to confirm temperature during the 30 minute hold period is not low enough to require an internal heater waiver.
Simulations show that temperature remains above -12 degrees C.
Results of 30-minute hold simulations: https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_X5lCYqnNRx1C
Increase accuracy of simulations in NX SST of worst case cold conditions to calculate max heater power required.
In worst-case cold conditions the heater is on with a constant power of 1.5 W
https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-analysis#h.p_4-WkyTY-Vbwy.
Review component data sheets to confirm that all units can operate in -15C to +50C.
Components meet the temperature specifications. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Tm-glNlFP63I
Perform simplified nodal analysis of spacecraft temperatures through a number of orbits until a stabilized temperature profile is established to estimate to estimate maximum and minimum temperatures of each spacecraft panel.
Nodal analysis results can be found here: https://docs.google.com/spreadsheets/d/16k-HVmqxj5R6XViiHKzW9K9Ke4O7SOul/edit#gid=1578752074
Simulations in NX SST of all worst case (hot and cold) conditions to evaluate component temperatures.
Results can be found here: https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-analysis#h.p_A5smhln57WJu
Evaluate results of worst case simulations to determine expected and worst case heater power required.
In worst-case cold conditions the heater is on with a constant power of 1.5 W.
https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-analysis#h.p_pPQQ7Zl47csk
Review component data sheets to ensure that humidity requirement is met by all thermal subsystem components/materials.
No components have functions that are likely to be affected by humidity. https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
Review design to confirm that it includes heaters.
The Design includes two heaters. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
Test prototype primary (Datec) heater installed in battery pack to verify sufficient heat flow is occurring (gradient less than 5 degrees C from heater surface to batteries).
Results show that gradient is less than 5 degrees C. https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-testing-phase-c#h.p_J1AQT-u9w3vy
Review design to confirm that it includes redundant heaters.
The Design includes a minco redundant heater. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
Test heaters can turn on and off during FlatSat testing.
See Testing Heater Operation.
Test operation of all spacecraft internal thermistors during FlatSat testing by a touch test.
Test results: https://sites.google.com/site/manitobasat1/subsystems/thermal/functional-tests-and-inspection-activities#h.57erxiccaalm
Review design to confirm that overtemperature sensors are included.
Temperature sensors are included, temperature readings will be used to cut current to heater if overtemperature. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_dnY2KFLAKiVa
Perform thermal simulations in an orbit with the same orbital parameters as the ISS.
Thermal simulation were performed using the orbital parameters of the ISS https://docs.google.com/spreadsheets/d/1tSQV8xy6o8ccCF606SOcvLWVoQ9qI0ffTZTKSeyn8Vk/edit#gid=0
Review bill of materials to confirm all procured components follow import conditions
Parts list & BoM: https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Tm-glNlFP63I
Review thermal design to confirm it complies with NASA space debris mitigation guidelines as documented in NASA Technical Standard NASA-STD-8719.14A.
No components have removable parts or FOD-generating coatings of any kind. https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
No risk of explosions (no batteries in thermal components).
Review component/material data sheets to confirm no hazardous materials are used.
No hazardous materials are used in the datasheets. https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
or parts list: https://docs.google.com/spreadsheets/d/12Y_8pywxbQ1IlvDqgZUz0z_I3wOYiH_7X_EVq5Xo-hM/edit
A waiver was previously filled for the use of silver in the thermostat.
Nanoracks has approved the BoM.
Review component/material data sheets to confirm outgassing requirement is met. Outgassing requirment is met if Total Mass Loss (TML) is greater than 1.0 percent or a Collected Volatile Condensable Material (CVCM) value of greater than 0.1 percent.
Outgassing requiremets are met for all thermal components. https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
Review design to confirm only fastners with thread size of 2-56, 4-40, or 6-32 are used.
No fasteners integral to thermal components- if fasteners are required, they will be selected by structure subsystem.
Review component data sheets to confirm the following pressures can be survived: airock Pressure: 0 to 104.8 kPa and airlock pressure depressurization/re-pressurization rate: 1.0 kPra/sec.
No parts are likely to be affected by pressures. https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
Review design to confirm there are no intentional detachable parts.
No parts have detachable components. https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
Thermal ICD with visuals of components: https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-icd#h.p_HTrJ-va9VWDF
Review design to confirm that any hazards present are controlled.
Only hazard in thermal subsystem is thermal runaway of batteries. Unlikely as satellite runs cold.
Risk of heater being stuck on is mitigated by mechanical thermostat in line with heater.
Risk registry & mitigations: https://sites.google.com/site/manitobasat1/subsystems/thermal#h.peeg87qa4772
Review component data sheets to confirm on orbit acceleartions of 2.0m/s^2 can be survived.
Unlikely for any components to be affected by accelerations as no movable parts except thermostat, which is high reliability (meant for extreme environments). https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
Review design to confirm components do not extend past volume limits of the NRCSD.
The solar panel thermistors are the only external thermal components. The solar panel does not extend past the NRCSD volume limits.
Review design to confirm all external components have a secondary locking feature.
All thermistors secured by both wires and epoxy.
Review design to ensure three-axis orientation system is used.
Simulations were performed based on a three axis orientation
See the figure just above results: https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-analysis#h.p_8QJrkf_dX4m9
Review design to ensure all components have a mounting path to the structure.
All thermal subsystem components are mounted to components from other subsystems.
Thermal ICD provides Mechancial interface information for all components https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-icd#h.p_HTrJ-va9VWDF
Review design to ensure thermal subsystem does not use ITAR controlled components.
Thermal system does not use ITAR controlled components. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Tm-glNlFP63I
Review design to ensure that selected hazard control methods are appropriate.
Design: https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
Risk & control methods: https://sites.google.com/site/manitobasat1/subsystems/thermal#h.peeg87qa4772
Review design to ensure all components have a minimum operational lifetime of 3 months.
All components are automotive grade or higher. https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
Review design to ensure thermal management subsystem does not contain pyrotechnics.
Thermal design does not contain any pyrotechnics. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
Review design to confirm thermostat does not contain a pressure vessel.
Only "sealed" part is the mechanical thermostat. This component is hermetically sealed with a very minimal internal volume (<1.8E-5 m^3). A sealed volume of this size poses minimal to no risk.
Thermostat datasheet: https://docs.google.com/document/d/1iUzgk7wSC9HAue9tmdm5WhFWZqvLEpOa4o-hD2LIzCE/edit
Review design to ensure all components are passive and self contained from integration to deployment.
No thermal subsystem components will be activated without power being activated (no batteries or energy storage).
Inspect thermal components to confirm no sharp edges are present.
No sharp edges are present for the thermostat, minco heater or thermistors.
Additional machining was done on the Datec heater but it is internal to the satellite.
Review design to confirm no components are used that have sharp edges.
Thermal components do not have any sharp edges.
Link to ICD with visuals of components: https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-icd#h.p_HTrJ-va9VWDF
Review work assignments to confirm student participation.
Iris is led by students. https://sites.google.com/site/manitobasat1/mission-objectives-1/team#h.p_U2VGhluD6JQS
Review thermal design to confirm failure of any thermal subsystem component shall not create detachable parts.
No components have any small parts on the outside that could come loose.
Datasheets https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
& ICD https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-icd#h.p_HTrJ-va9VWDF
Review design to confirm thermal subsystem does not require operation of any components for a minimum of 30 minutes where hazard potential exists.
30-minute hold simulations show that the batteries temperature does not fall below -12 degrees C
Review thermal design to confirm no thermal components require any electrical or data interfaces between the thermal management subsystem and the NRCSD.
There are no electrical or data interfaces between the thermal system and the NRCSD. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
Review design to confirm that no combination of two failures, two operator errors (or one of each), can cause a disabling or fatal personnel injury or loss of one of the following: loss of ISS, loss of a crew-carrying vehicle, or loss of major ground facility
No failures that could occur while unpowered (on ISS) that would cause any harm.
Perform analysis to assess and quantify the risk of battery overheating.
The spacecraft runs cold and the power is cut off by software to prevent overheating.
Thermal analysis https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-analysis#h.p_ESaHEZYj7awK
Cycle power to thermal components on and off to ensure system can recover from power shutdowns.
See Testing thermal components while cycling power.
Review design to confirm no components are used that are sensitive to power upsets.
No components are sensitive to power upsets. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
Analyze simulation data to confirm that components will not go out of acceptable temperature ranges if power to thermal subsystem is stopped for five minutes.
In worse case cold conditions, the heater duty cycle is at 65% keeping the components at an optimal temperature.
Temperature ranges for the different components are listed in the tables of result for worst case hot and cold simulations: https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-analysis#h.p_ESaHEZYj7awK
Review thermal design to confirm no batteries are used.
The thermal design does not use any batteries. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
Review design to confirm thermal subsystem does not contain enclosed containers.
The thermal design does not contain enclosed containers. https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Tm-glNlFP63I
Review design to confirm that thermal control subsystem has an approved secondary locking feature for all fasteners or subcomponents.
All thermistors are secured by both wires and epoxy.
Thermostat is secured by wires and fasteners
Datec heater is secured by fasteners, epoxy and wires.
Redundant heater is secured by adhesive, epoxy and wires.
Review design to confirm thermal components are capable of withstanding up to five (5) deg/sec/axis tip-off rate
No sensietive components. https://drive.google.com/drive/folders/1TwBD_-N01MpZCW0LGTAtrRFwpIcSFKZG
Review thermal subsystem design to confirm it is capable of withstanding the expected thermal environments for all mission phases, which are enveloped by the on-orbit, EVR phase prior to deployment.
All thermal subsystem components where selected to withstand expected thermal environment: https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
V-THE-0810
Vibration test engineering model thermostats to qualification levels to verify they can withstand the vibration environment of launch.
Thermostat tested and passed at qualification levels. https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-testing-phase-c#h.p_8KGj-s6GwbgT
Review thermal subsystem design to ensure it only uses fasteners with a hex head.
No fasteners integral to thermal subsystem design.
Review component data sheets to ensure all thermal subsystem electronics can withstand a radiation dose of 1.5k rad over the three year mission duration
Thermistors are the only electronic devices in the thermal subsystem that are outside of the spacecraft and most directly exposed to rediation. See reference from TE on thermistor stability in radiation environment (https://www.te.com/content/dam/te-com/documents/sensors/global/te-faqs-ntc-radiation-exposure.pdf) which indicates that they are minimally affected by radiation. TDK chip thermistors are made from electrical conductor materials (metals) not semiconductors, and electrical conductor materials are less sensitive to radiation effects.
Review thermal subsystem design to confirm all components can operate with an input voltage of 6.4 + - 0.4 V.
Datec heater operates at a nominal voltage of 3.3 V
Power consumption: https://sites.google.com/site/manitobasat1/subsystems/power/power-design#h.8gawm07jbtbx
Review results of thermal simulations and planned thermistor locations to confirm thermistors monitor temperatures locations of required telemetry.
Thermal Design: https://sites.google.com/site/manitobasat1/subsystems/thermal#h.p_Iv_8BzOvxBnS
Required telemetry https://sites.google.com/site/manitobasat1/subsystems/flight-software/flight-software-icd#h.p_p5GhwImKPqLG
Thermistor locations: https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-icd#h.p_fMvOBFCnpkjE
Simulation results: https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-analysis#h.p_A5smhln57WJu
Simulations show that thermistor locations are adequate to provide the thermal telemetry required by the thermal design.
Re-run worst case hot and cold orbital simulations with update thermal model of spacecraft, re-confirm all results still meet requirements.
All results still meet requirements: https://sites.google.com/site/manitobasat1/subsystems/thermal/thermal-analysis#h.251f44izow49