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Telecon tomorrow (Thursday) @ 5 pm Eastern time

Hi all!

Happy 2019! Telecon tomorrow (Jan. 10 in North America, Jan. 11 in Australia) at the regular time: 5 pm Eastern (2 pm Pacific, noon Hawaii, 23.00 European, 9 am Eastern Australia). One (of the 3) new photodiode precision amplifier boards is now populated with components and is presently being tested; and two new SHX144 transceiver boards are here, have been tested, and work well (I'll send a bunch of photos in a progress report I'll send tonight); and also lots of new updates on station-keeping prediction and simulation software. More discussion items for tomorrow's telecon include: flight/telescope plans and tests; construction, drop testing, and other tests of the new gondolas/payloads; light sources and light source modelling; goniometric and pre- and post-flight calibration; propulsion work; nanosat bus and payload solid models; computing / website / TWiki forums and e-mails; grant applications; and recap of schedules.

Here's how to connect:

1) Open Skype on your computer (note that of course, you should first install Skype, http://www.skype.com, on your machine if you haven't already).

2) In the "Contacts" menu, add me ( jalbertuvic ) as a contact, if you haven't already.

3) Just wait for me to Skype-call you at the usual time (5 pm Eastern, 2 pm Pacific, etc).

4) If there is any trouble, or if you don't get a Skype-call for some reason and would like to join, please just send me an e-mail (jalbert@uvicNOSPAMPLEASE.ca).

Here's the tentative agenda:

I) Flight & telescope plans, and upcoming tests

II) Construction, drop tests, and other tests of the new gondola and payload

III) Diffused light source and its modelling, pre- and post-flight calibration, and goniometric calibrations

IV) Solid modelling

V) Computing/website, including recent flight control and simulation progress

VI) Grant applications


Talk to you all tomorrow, thanks!!!


-- jalbert - 2019-01-09

Hi all!

My apologies for the delay! -- here are minutes on Thursday's telecon (attendees Arnold Gaertner [NRC] & me) plus a quick progress report on ALTAIR balloon work done over the holidays -- please just reply with (or let me know) any corrections -- thanks! :

One of our three new precision photodiode amplifier boards is presently being populated with components, and simultaneously being tested, by designer Andrew Macdonald. Here are photos of the present status of the front and back of that board:

After that board is finished being populated and tested by Andrew, he will turn that amplifier board over to me, for my own testing and installation into the ALTAIR payload, and then he will begin populating and testing the other two (identical) amplifier boards:

Our two new SHX1-144 transceivers arrived in late December, and we installed them into two new transceiver boards, and removed one of our two old ones from the payload for testing -- here are all 4 of them:

The bottom board with the cutouts was the SHX board that was in the payload: when I installed it in the payload (about a year ago), I had to cut a couple of bits out of that board so that it would fit. That board in the payload worked fine both just after those cutouts were made, as well as for over 6 months after that, until a couple of months ago. But now, it appears to be the one of the 4 boards that is not working. We've e-mailed Radiometrix to see if there might be any way we possibly might be able to recover its transceiver, but if not, I'll need to make cutouts in another board that will then become the SHX board that will fly in the payload (and our other two functional SHX boards will go into the Capella and Deneb ground stations respectively).

I'll be picking up our 12 OSI Optoelectronics UV-015 photodiodes and 11 windowless Hamamatsu S2386-8K photodiodes from the Stubbs lab at Harvard in the third week of February.

I updated the flight path prediction in AIFCOMSS to base ascent and descent rates, as well as predicted balloon burst altitude, on physical properties of ALTAIR (e.g., amount of helium in the balloon just prior to launch, the mass and the other physical properties of the balloon latex, mass and properties of the gondola, parafoil, and rigging, etc), rather than what they previously were, which were just ad hoc constants (e.g. ascent rate of 5 m/s, descent rate of 2 m/s, burst altitude of 30000 m) and, thus, to then properly calculate instantaneous ascent and descent rates from drag and gravity. That is all updated, uploaded, and working now -- and one decent test that it is properly working is that the flight path changes some with respect to the ad hoc constant flight path prediction, but most definitely not enormously or ridiculously, so that's one good sign. The flight path prediction of course uses wind information from real-time NOAA data and predictions, bur at present the prediction doesn't also use real-time values of atmospheric pressure and temptation at all latitudes, longitudes, and altitudes, so my next step is to update the prediction so that that real-time pressure and temperature info is properly included too. The code is all in the pred_src directory of the AIFCOMSS Github repository:


and our corresponding ALTAIR onboard software (as always) is in:


Mark Lenckowski has completed the stabilized pole for the new 10-meter-high drop test setup at Victoria:

As you can see (faintly), he affixed side-struts and guy wire to the PVC pole, to prevent it from bending in either of the two transverse directions, so it can now be raised to vertical, from horizontal, without bending or breaking.

The survey-tripod-mounted device to cross-check yaw-pitch-roll information from the gondola (e.g., on days before/after flights) is constructed now, thanks to Mark Lenckowski -- photo at:

and all that remains to be done is to finish the small fitting between the device and the bottom of the payload. The purchased hardware in it includes both the survey tripod (http://www.cpotools.com/cst-berger-60-alwi20-o-aluminum-tripod-with-quick-release--orange-/cstn60-alwi20-o,default,pd.html), two adjustable angle mounts (http://www.thorlabs.com/thorproduct.cfm?partnumber=AP180), and a rotation mount (https://www.thorlabs.com/thorproduct.cfm?partnumber=RP01). That last fitting to attach (temporarily, pre- or post-flight) the upper adjustable angle mount to the payload landing gear has been started and will be completed here in the next couple weeks.

We're currently revising the draft initial contractual agreement from our colleagues at Globalstar Canada regarding 2 initial SPOT Trace devices (and their service plans) for the educational side-project for the upcoming NATO SPS application, in which classrooms in elementary and high schools could launch company-donated SPOT Traces using party balloons (or a more environmentally-friendly version thereof), and track them to learn more about winds at different levels in Earth's atmosphere.

Houman will send Cordell and/or us updated sections of his master's thesis soon -- that information will be extremely useful to us going forward. Also, Susana and Nathan, it would be very helpful for us all to get the JHU students' final writeup when you have a chance.

Our next grant applications will be a NATO "Science for Peace and Security" application, together with Australian colleague partners.

Our next telecon is in two weeks from now on Thursday Jan. 24 (5 pm Eastern, 2 pm Pacific as usual).

Cheers, and talk to you again in 2 weeks on Jan. 24! -- thanks all!!!!!


-- jalbert - 2019-01-12

Title Telecon tomorrow (Thursday) @ 5 pm Eastern time
Forum ForumGeneral
Topic attachments
I Attachment History Action Size Date Who Comment
JPEGjpg ALTAIRMostlyPopulatedPrecisionPDAmpBoardBottom.JPG r1 manage 1571.3 K 2019-01-11 - 00:43 JustinAlbert Partially-populated photodiode amplifier board bottom view photograph
JPEGjpg ALTAIRMostlyPopulatedPrecisionPDAmpBoardTop.JPG r1 manage 2181.4 K 2019-01-11 - 00:42 JustinAlbert Partially-populated photodiode amplifier board top view photograph
JPEGjpg ALTAIRNewAndOldSHX1Boards.JPG r1 manage 2639.8 K 2019-01-11 - 00:44 JustinAlbert Two new, plus two old, SHX1 144 MHz transceiver boards top view photograph
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Topic revision: r3 - 2019-01-12 - JustinAlbert
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