Science and Engineering » Hönnun » Skyward Sword

h1. Research and Design

* [[FRDPRC Analysis]]

* [[Debrief Notes for Test Launch]]

h2. Balloons

Types of high altitude balloons

* Latex weather balloon - http://en.wikipedia.org/wiki/Weather_balloon

* -Valved latex balloon-

* -Superpressure balloon - http://en.wikipedia.org/wiki/Superpressure_balloon-

* -Zero pressure balloon - http://www.eoss.org/faq/zero_pressure.htm-

h2. Testing

* Impact test

** The name of house guard in Höfðatorg is Albert S:6618467

He said it will be no problem if we want to drop something of the roof for testing. The height of building is 74 m. Contact him one day before we want to do the test.

* Freezer test

* Water test

** We need to ask about dropping things into the pool at RU.

h2. Release Mechanism from Seglagerðin

* -We got offer from Seglagerðin Ægir for the release mechanism. Which is two fabrics under and over the balloon with two zip on the top fabric to release the balloon 94440kr with tax, 75251kr with out tax. We are looking for lower price.-

h2. Release Mechanism Test

Bogi, Örvar and Vikar made a test on the release mechanism.

The results from test:

* If it is windy the fabrics flap a lot and can damage the balloon.

* The coses did not fit together as we expected so we could not zip two fabric together.

* Have to find another way, f.x find large house and fill the balloon inside.

h2. Electronics

We may want to consider replacing the SPOT device because of it's 24h limitation and track frequency.

Alternative devices

* http://www.cybergraphy.com/English/gps_satellite.htm

* http://www.spidertracks.com/store/spiders/spider-s3-lite

** Uses Iridium

** Max tracking height is 18km

* http://www.yellowbrick-tracking.com/?page_id=1555

** Uses Irridium

** Max height unknown - inquiry sent via email

* Comparison of GPS recievers regarding maximum height

** http://showcase.netins.net/web/wallio/GPSrcvrsvs60kft.htm

h3.  Control system

Niklas (with guidance from Joe)  is working on the Arduino control system.

* Failsafe (cut string)

** ni-chrome wire heater via a MOSFET

** Simple: timer that cuts after some predicted time

** GPS: cuts when farther than the boundary of Iceland

* Sensors

** GPS

*** http://inventeksys.accountsupport.com/store/ISM300F2-C5-V0004.html  <-- special high altitude chip/firmware

*** Arduino Logger shield http://www.adafruit.com/products/98 USD19.50

*** EM-406A GPS Module http://www.adafruit.com/products/99  USD60.00

** Temperature

*** Light and temperature logger shield http://www.adafruit.com/products/249 USD37.50

** Pressure (altitude)

* Wireless

** Most seem to be limited to 500M

** Dirt Cheap Wireless http://www.dcdwireless.com/overv.htm