Acrob030: Rozdiel medzi revíziami
Z SensorWiki
(→Theory behind) |
|||
| Riadok 43: | Riadok 43: | ||
* http://earthsci.org/education/fieldsk/declin.htm | * http://earthsci.org/education/fieldsk/declin.htm | ||
* http://www.nationalatlas.gov/articles/geology/a_geomag.html | * http://www.nationalatlas.gov/articles/geology/a_geomag.html | ||
| − | * Inclination and Declination calculator: http:// | + | * Inclination and Declination calculator: <BR> http://ngdc.noaa.gov/geomag/magfield.shtml |
| − | You will need Your home coordinations. | + | |
| + | You will need Your home coordinations. Determine Your location using Google Maps or GPS. | ||
Tip: how to find lat and lon without the GPS: http://astro.unl.edu/naap/motion1/tc_finding.html | Tip: how to find lat and lon without the GPS: http://astro.unl.edu/naap/motion1/tc_finding.html | ||
Verzia zo dňa a času 12:52, 26. 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://ngdc.noaa.gov/geomag/magfield.shtml
You will need Your home coordinations. Determine Your location using Google Maps or GPS.
Tip: how to find lat and lon without the GPS: http://astro.unl.edu/naap/motion1/tc_finding.html