Category Archives: 1-Ground

Satellite Tracker

Tracking satellites can be fun (where is the ISS now?) … and complicated. Fortunately there are some algorithms that can help like the SGP4.

I’ve used an available php implementation of the SGP4 algorithm and made a simple satellite tracker application showing the ISS, but really it can show any satellite as long I feed the proper Two Line Element from CelesTrack.

Check the link and you’ll see where the ISS is hovering now: www.spacemig.com/satellite-tracker

 

Satellite Tracker

And you can check how accurate this is by going to this link:

http://www.n2yo.com/?s=25544

References

  • http://en.wikipedia.org/wiki/Simplified_perturbations_models
  • http://en.wikipedia.org/wiki/Two-line_element_set
  • http://www.celestrak.com/NORAD/elements/

Starting with Python

python logo
Python logo

For about a year I have been programming in Python as a Matlab alternative. I love Matlab but I can’t afford being tied to a licence. Python is free, open source, and so far I have been able to do everything I did with Matlab. I am fairly impressed!

Python is becoming, or it may be already, a main stream programming language, specially for open source software. Since it’s a scripting language a lot of programs use it for scripting in that app. A few examples are Blender for 3D modeling and animation, FreeCad for 3D mechanical modeling, Fenics for solving differential equations by finite element methods, etc. Many universities have adopted Python in their class work, MIT, Georgia Tech, UC Davis, etc.

If you want to start with Python let me recommend the following:

  1. Use Enthought! Yes, I know … there is also a licence attached if you really want full support and all the packages. But it’s free if you have a .edu email and even if you don’t have one there is a totally free version of Enhtought: Canopy Express! By the way, the Enthought distro works on Mac, Linux and Windows. It’s perfect!
  2. If you really… really don’t want to be attached to a licence (I made my peace with Enthought since they have a free version) you can use Spyderlib. It’s also an Integrated Development Environment (IDE) like Enthought but has a few less python libraries… but you can install them separately with a bit of pain.

If you want to lear more about Python and how to get started check these references:

Starting with EAGLE

The FREE version of  CadSoft EAGLE PCB Design Software is great to do PCB design for simple boards, up to 10×8 cm area, up to 2 layers. Here are some steps to get started:

1. Download the free version of Eagle (Mac, Linux, Win) just go to: http://www.cadsoftusa.com/download-eagle/

2. Go through the 3 tutorials made available on the Sparkfun website:

as an extra it’s good to go through this article as well:

3. Check these videos

If you don’t want to deal with size or layer limits then try KiCad: http://www.kicad-pcb.org/