Hey All,<br><br> Good analysis. From what I found out about tracking;<br><ul><li>When the GPS device says it is at a specific location, due to position update delays, that could mean the position 15 minutes ago. So it is essential that you must not head towards the last position update, but wait for the payload position to become fixed before attempting recovery. It would also benefit us to have a GPS on the tracker and a GPS on the balloon so their positions are known to base station people. Altitude, speed and heading reporting is also helpful for determining the target's positions and what is happening to them.</li>
<li>Along with cell phones, ham radios will help with communication.<br></li><li>GPS is not 100% accurate. A reported position could mean the payload is within 100 feet of defined position. Also, the more cliffs/obstructions you have around you, there will be less GPS satellites recieved and GPS accuracy drops.<br>
</li><li>Recovery is not always ideal. The payload can land in rough terrain and require you to do tree-climbing, rock/mountain climbing and/or hiking. Be sure to wear/prepare gear for such an expedition. The trackers typically brought with them rope and ladders to reach such hard places.</li>
<li>Bring a driver's GPS (TomTom, etc.), a hand-held GPS and some kind of close-range tracking. They will comnplement each other for different phases of the search (driving there, homing in and looking around the brush). You can use these to home in to the position of the payload's reported GPS if you are using GPS tracking.</li>
<li>Not all roads to the payload show up on the GPS and offroading is sometimes a must. Use off-road capable vehicles and bring a detailed map of the region of terrain and roads so you can find a path.<br></li><li>The locals are really quite friendly and familiar with balloon tracking, but be sure to respect private property lines and ask permission before entering. Also, beware farm animals/dogs/bulls. You do not want to enter their territory during a search.</li>
<li>Bill Brown may allow us to piggy back again. We'll have to organize it with him.<br></li></ul>Otherwise, our payload mostly stayed on and functional. When I picked it up, the phone was still on, but the camera had shut off. (Batteries were okay and full for both). The software is the issue as the tracking application on the phone shut down in-flight and the camera script stopped working due to an inadvertent button trigger.<br>
<br> - Ethan<br><br>P.S. Good job guys. We may not have gotten everything, but we did learn a lot of valuable stuff about balloon flight. Let's speak more at the meeting.<br><br><div class="gmail_quote">
On Sat, Apr 10, 2010 at 5:34 PM, Satyam Nayak <span dir="ltr"><<a href="mailto:nayaksatyam@gmail.com">nayaksatyam@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Positives: Nothing lost.<br><br>Negatives: Nothing worked.<br><br>Camera: <br>Somehow stopped taking pics while still being packed. Need to determine if this was because of unintended button pushing or if it was because of too much flipping and turning while packing.<br>
The way it works with CHDK is that the shutter button starts and stops the script.<br> <br>For human convenience, the shutter buttons have a slightly higher profile, making them easy to click - and it is entirely possible that a zip tie dug into it once, and that caused it to pause the script.<br>
<br>We need to find a way to package the camera such that none of the elements are pressing into any buttons. <br><br>An ideal solution would be a foam enclosure of just the right size that we seal up after setting off the camera. I wonder if there is a way of doing this. <br>
<br><br>Tracking / Cell phone:<br>Stopped working even as we were packaging, but even if it had worked initially, we have no idea how it will hold up later on. I think everyone is in the favor of ditching the camera and going with radio chirpers. We need to investigate into this.<br>
<br>Another thing is we need to make sure that the tracker keeps going for several hours, in case something goes wrong and our payload gets towed to another place. Even if it chirps once every 30 mins after the first few hours, we will at least have a general idea of where it is going.<br>
<br>I am not exactly sure what the story for today was, I think Ethan can fill us in on the details.<br><br>Packaging:<br>The foam board backing is not a bad idea, but I think we need to pair it with something more structural for a standalone launch. We can even string them up separately like the way they did to the payloads today, that way we can use the best packaging for each module without compromising the other ones. <br>
<br>It would also be nice to work out a design such that we can pre-assemble parts and put them together with relative ease once we put in the main components - since there really is no way around having to activate components just before the launch. I guess we should aim for a build time less than what it takes to inflate the balloon, so we can start as the balloon is being inflated, and have everything ready to go as by the time the balloon is ready.<br>
<br>Component coupling:<br>After today's experience I'd say that we want any component to rely as little as possible on any other component, to avoid catastrophic failures. We were not planning on any nonessential coupling any way, but I figured it was worth repeating.<br>
<br><br>Overall, I think it was a good learning experience. It would have been nicer if at least the camera had worked, but this is at least much better than losing the payload without knowing that the camera had stopped working too. So all in all, given that both of our components failed, this is possibly the best outcome we could have had. We'll at least know much better when we send out our own standalone payload. Saved us a fair amount of money too. <br>
<br>
I am sure I am forgetting something, feel free to add your thoughts.<br>
<br>
Also Ethan probably has some observations from the tracking experience
as well.<br><font color="#888888"><br>-Satyam<br>
</font><br>_______________________________________________<br>
HSIS mailing list<br>
<a href="mailto:HSIS@lists.makerslocal.org">HSIS@lists.makerslocal.org</a><br>
<a href="http://lists.makerslocal.org/mailman/listinfo/hsis" target="_blank">http://lists.makerslocal.org/mailman/listinfo/hsis</a><br></blockquote></div><br>