Development and Testing

The best way to set up a PITS board on your desk (e.g. to test that it all works and that you can receive data) is to connect the Pi to a wired network and to connect to it via ssh.

A wired network is best as you don't have to worry about setting up the details of your wireless LAN.  You do of course need a model B or B+ or V2 B Pi, which means you'll be testing on a different Pi to the one you fly (which will be an A or A+) but that's not an issue at all.

To ssh into the Pi you need to use an ssh client.  putty is a very good one, and is a free download.  You will need to know the IP address of the Pi, and the easiest way to find that is to boot the Pi with a screen connected - the IP address is shown at the last stage of the boot process.  Another method is to use something like "Advanced IP Scanner" to find the Pi's IP address.

To power the Pi and PITS during development, just connect the Pi to USB power as normal.  Do not use USB power and battery power at the same time (you won't do any harm but you will drain the batteries for no reason).

Batteries

Only use Energizer Lithium cells - they are specified for use in cold environments (down to -40C which is much colder than the inside of your payload will get).  We recommend the use of 4 AA cells in the supplied holder.  We also recommend taping the batteries down with duct tape so that they don't disconnect on landing.  Tape down the the battery connector for the same reason.

AA cells will give you 20 hours run time on the original PITS with a model A, and slightly less on the current board with an A+.  AAA cells will give 6-7 hours. Since a typical flight is about 3 hours you may feel that the latter is plenty, however it doesn't leave a lot of time for you to find the payload after landing.  Remember also that any delays in launching will eat into that time.  So, unless you've done this before and are confident in your launch and chase abilities, please use AAs.

Photography

We recommend sticking with the default image sizes.  Larger images can take a long time to download, and it's good to get plenty of relatively small images throughout the flight rather than a few large ones.  Remember that, alll being well, you will recover the payload anyway so you will then have all of the full-size images.

Remember that, as with any camera, you should delete saved images from the SD card before you fly, otherwise you risk the card filling up during the flight!  The images are in /home/pi/pits/images.

The camera would normally be positioned to aim horizontally from the payload, though of course it's up to you what view you want.

 

Published on 1st June 2015