PowerPoint Presentation

Colorado Space Grant ConsortiumDemoSat-BColorado State UniversityMatthew Jui, Ian Patterson, Mark Spowart, Todd WallisJune 8 2011Critical Design Review

12The payload for the CSU DemoSat-B 2011 project is a CO2 mapping with respect to altitude System, C-MAS. This payload will measure concentrations of carbon dioxide in the atmosphere throughout its flight and then will be matched with corresponding altitudes upon recovery. Although weather balloons with similar measuring equipment are launched daily, what makes C-MAS unique is that the data that is taken is done so at a much higher altitude and at a lower cost, while still maintaining a high level of accuracy.

OverviewObjectivesPayload will measure concentration of CO2 ,RH, temperature and pressure at intermittent altitudesPayload will operate by itself for 200 minutes and take data for both ascent and descent

Optional ObjectivesPayload will visually record weather conditions through an attached camera or video camera

Topic BackgroundMultiple organizations have conducted similar research but with different techniques. (sample from aircraft, and Space observation)3

CO2 concentrations are cyclical but are increasing by about 2 ppm/yr.Current CO2 concentration at sea level is 394.4ppmAlthough this is a relatively small overall concentration, it is an important component of the earths atmosphere because it emits and absorbs infrared radiation at wavelengths that play a significant role in the greenhouse gas effectA peak in annual concentration levels happens in Spring when plants are in full bloomIn July we expect to see relatively constant concentrations throughout the atmosphereCO2 concentrations in our atmosphere

4Schematic of major Internal Components

Concept of OperationPump provides volumetric sample air flow through systemHeater brings sample air temp to w/ in sensor operating tempCO2 meter measures CO2 concentrations, RH, TempData logger saves all data including external pressure sensor

5Mission Requirements Matrix

RequirementMethodStatusThe payload must not exceed a weight of 1.5 kg.Design, TestThe payload must operate on 9V or less.Design, TestThe payloads center of gravity (CG) shall be as close to the geometric central axis as possible. Design, AnalysisThe inlet air must be heated to approximately 0 C before interacting with the CO2 sensor.Design,AnalysisThe payload will record CO2, temp, RH, pressure values every 30 seconds for a minimum of 200 minutes.Design, AnalysisThe payloads shell will protect the internal components against a load of 15 gs.Design, AnalysisThe internal components will remain secured to the mounting plate when exposed to a load of 15 gs.Design, AnalysisCompleted project must cost under $1000.Plan The spacecraft must be capable of meeting all mission objectives.Design, Test667

Electronics Schematics

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Flow Chart Block DiagramStructural Drawings

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10Subsystems OverviewPower SubsystemBattery must stay between 32 and 140 F during all operationVoltage must be regulated from 7.4 to 5V depending on the circuit element

Air Flow SubsystemFlow rate minimum of .3 liters per minuteNo detectable leaking may occur between inlet and exitAir must be maintained above 0 C

Heating SubsystemMust maintain both air flow and power subsystem heat requirements

Sensor SubsystemMust take accurate measurements of both CO2 concentration and internal pressure

Parts List

Test PlansTestStatusResultNotesdropcompletesuccessStair pitchcompletesuccesswhipcompletesuccesscoolerpendingLiquid NitrogenVacuum chamberScheduled for 7/1Must be flight ready14

Bubble TestUsed to measure volumetric flow rate15