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(Nová stránka: Following text will show You a basic connection and operation of the digital compass module. Obrázok:Parallax_HM55B.jpg Product page: [http://www.parallax.com/Store/Sensors/C...) |
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| Riadok 26: | Riadok 26: | ||
Arduino page about HM: http://www.arduino.cc/playground/Main/HM55B | Arduino page about HM: http://www.arduino.cc/playground/Main/HM55B | ||
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| + | == Theory behind == | ||
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| + | What actually measures magnetic sensor? Yes, the strength of the magnetic field. It is just random | ||
| + | coincidence, that current north magnetic pole is near the geographic one. | ||
| + | Also, the Earth magnetic field is very unhomogenous. See picture: | ||
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| + | http://netdaw.com/wp-content/uploads/2010/10/solar_wind1.jpg | ||
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| + | Also beware of the magnetic inclination and declination... | ||
| + | More: | ||
| + | * http://www.compassdude.com/compass-declination.shtml | ||
| + | * http://earthsci.org/education/fieldsk/declin.htm | ||
| + | * http://www.nationalatlas.gov/articles/geology/a_geomag.html | ||
| + | * Inclination and Declination calculator: http://www.ngdc.noaa.gov/geomagmodels/struts/calcIGRFWMM | ||
| + | You will need Your home coordinations. STU is located at the N48.xxxxx E17.xxxxx (TODO) | ||
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| + | Tip: how to find lat and lon without the GPS: http://astro.unl.edu/naap/motion1/tc_finding.html | ||
Verzia zo dňa a času 22:36, 25. február 2011
Following text will show You a basic connection and operation of the digital compass module.
Product page: #29123 Hitachi HM55B Compass Module
- Documentation (.pdf)
- Chip datasheet (.pdf)
Schematic diagram:
Demo program:
Demo software:
Arduino page about HM: http://www.arduino.cc/playground/Main/HM55B
Theory behind
What actually measures magnetic sensor? Yes, the strength of the magnetic field. It is just random coincidence, that current north magnetic pole is near the geographic one. Also, the Earth magnetic field is very unhomogenous. See picture:
http://netdaw.com/wp-content/uploads/2010/10/solar_wind1.jpg
Also beware of the magnetic inclination and declination... More:
- http://www.compassdude.com/compass-declination.shtml
- http://earthsci.org/education/fieldsk/declin.htm
- http://www.nationalatlas.gov/articles/geology/a_geomag.html
- Inclination and Declination calculator: http://www.ngdc.noaa.gov/geomagmodels/struts/calcIGRFWMM
You will need Your home coordinations. STU is located at the N48.xxxxx E17.xxxxx (TODO)
Tip: how to find lat and lon without the GPS: http://astro.unl.edu/naap/motion1/tc_finding.html