Zeile 12: |
Zeile 12: |
| | | |
| ==Get the Time== | | ==Get the Time== |
− | [[Image:Arduino_DS1307.jpg|thumb|timer chip DS1307 with Arduino]] | + | [[Image:Arduino_DS1307_FritzingExport.jpg|thumb|timer chip DS1307 with Arduino]] |
| To get Greenwich Time (aka UT) I use a DS1307 chip. | | To get Greenwich Time (aka UT) I use a DS1307 chip. |
| Following the description of http://www.glacialwanderer.com/hobbyrobotics/?p=12 | | Following the description of http://www.glacialwanderer.com/hobbyrobotics/?p=12 |
Zeile 18: |
Zeile 18: |
| 4.7K ones are just as fine. | | 4.7K ones are just as fine. |
| I have taken the code from that site and tucked the complexity | | I have taken the code from that site and tucked the complexity |
− | into an Arduino libary (DS1307.h) | + | into an Arduino libary (DS1307H.h) |
| | | |
| ==Calculate Azimuth and Elevation== | | ==Calculate Azimuth and Elevation== |
Zeile 30: |
Zeile 30: |
| and you can download it [http://www.psa.es/sdg/sunpos.htm here] as C++ code. | | and you can download it [http://www.psa.es/sdg/sunpos.htm here] as C++ code. |
| There are adaptions neccessary for Arduino, though. | | There are adaptions neccessary for Arduino, though. |
− | The formulas for calculating the [http://en.wikipedia.org/wiki/Julian_day Juliand Day] | + | The formulas for calculating the [http://en.wikipedia.org/wiki/Julian_day Julian Day] |
| are not working properly on Arduino due to reduced double precision. | | are not working properly on Arduino due to reduced double precision. |
| Therefore, I have adapted them, expecting only Julians dates starting from 1.Jan. 2000. | | Therefore, I have adapted them, expecting only Julians dates starting from 1.Jan. 2000. |
| These calculations I have put into another library (Helios.h) | | These calculations I have put into another library (Helios.h) |
| + | |
| + | Use following program plus libraries for older Arduino IDE (0023 and older): |
| + | {{zip|SolarTracker4Arduino.zip|14KB|Version from 09.03.2011}} |
| + | |
| + | For newer Arduino IDE (1.0.1 and later) use instead the following package, |
| + | {{zip|SolarTracker4Arduino1.0.1.zip|17KB|Version from 16.01.2015}} |
| + | |
| + | Once you got it running, verify the calculated positions, for instance with |
| + | [http://www.sunearthtools.com/dp/tools/pos_sun.php solar position calculator] from |
| + | sunearthtools. (Attention: SolarTracker4Arduino does NOT account for daylight saving time (DST), |
| + | you have to determine UT (when you set your timer chip) as if there was no DST at all. On the other hand, sunearthtools allow using DST, |
| + | and this option is selected by default. |
| | | |
| ==SPA Algorithm== | | ==SPA Algorithm== |
Zeile 42: |
Zeile 54: |
| In this paper methods have been worked out according to the book from | | In this paper methods have been worked out according to the book from |
| ''Jean Meeus: Astronomical Algorithms, Willmann-Bell, Richmond 2000 (2nd ed., 2nd printing)'' | | ''Jean Meeus: Astronomical Algorithms, Willmann-Bell, Richmond 2000 (2nd ed., 2nd printing)'' |
− | a widely accepted text book for astronomic calculations. | + | a well known text book for astronomic calculations. |
| The calculations are, however, very extensive; for Arduino I chose the simpler PSA. | | The calculations are, however, very extensive; for Arduino I chose the simpler PSA. |
| Implementations and references for both algorithms I found thanks to the code from | | Implementations and references for both algorithms I found thanks to the code from |
| [http://klaus.e175.net/solarpositioning Klaus Brunner]. It was also a valuable help for debugging | | [http://klaus.e175.net/solarpositioning Klaus Brunner]. It was also a valuable help for debugging |
| the Arduino implementation. | | the Arduino implementation. |
| + | |
| --[[User:Hannes.hassler|Hannes.hassler]] 13:36, 3 March 2011 (CET) | | --[[User:Hannes.hassler|Hannes.hassler]] 13:36, 3 March 2011 (CET) |