Getting Pointing Information from gpredict for use in an External Program
Special thanks to KN4UU’s post on:
https://community.libre.space/t/gpredict-python-rotator-control/1972/6
Thought it might be more helpful to go in a bit more detail (also so I won’t forget).
One day, when I get time (yea right) I want to make a custom satellite tracker. The thought is to use inexpensive Raspberry Pi and an Arduino to do the stepper control. I would run gpredict on the Pi, and write a serial string containing the azimuth and elevation data to the Arduino. I would ssh/vnc into the Pi to select the satellite I wanted to point to. The Arduino would have a cheap inclinometer and compass connected and would simply use a control loop to move the device via stepper motors until the the position data matches the target. The first step is to compute the pointing data.
Gpredict does a good job of this. So, we now need to get the pointing data out of gpredict in a fashion we can send to an Arudino. This method basically uses rotctld as a pass-thru and only uses a small fraction of its functionality (not really how it was intended to be used).
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