Construction, programming and testing of measurement equipment for microbe culturing in space : Contribution to the MOREBAC experiment, part of the MIST-project

Sammanfattning: Many different bacteria have essential roles in the process ofrecycling organic waste, making them useful tools when it comes toestablishing artificial ecosystems, a key technology to master inthe expansion of human space travel.In order to further investigate bacteria growth conditions duringspace travel, the MOREBAC experiment was formulated. The objectivewas to design an experimental setup and develop measurementequipment with the capability of confirming successfulresuscitation of freeze-dried bacteria in space by measuringbacteria growth, on-board the student-built MIST-satellite.The experimental setup prototype consisted of an acrylic chipwherein the bacteria would be placed during experiments and anoptical measurements configuration using a photosensor with thepurpose of detecting bacteria cell growth. For experimentalenvironment monitoring, a temperature sensor and a pressure sensorwere calibrated.An Arduino Nano microcontroller was programmed to control allelectrical components during measurements. During the opticaldensity measurements blue dyed water and E.coli bacteria innutrition media were used as test samples.Provided varying blue dye or bacteria cell concentrations, in theform of dilution series and growth-over-time-series, the equipmentproved capable of producing measurements that indicate the opticaldensity of the test sample.Furthermore, a prototype experiment protocol simulating eventsthat will occur in the final experiment design, was implementedand was able to produce real-time monitoring graphs of optical,temperature and pressure measurements, as well as documentation ofall events and measurement data.