Discussion Forum » General »

Telecon tomorrow (Thursday) @ 5 pm Eastern time

Hi all,

Telecon tomorrow (July 9 in North America, July 10 in Australia) at the regular time: 5 pm Eastern (2 pm Pacific, 11 am Hawaii, 23.00 European, 7 am Eastern Australia). Success (finally!) on the update of AIFCOMSS for Python 3 (and the resulting updated Pydap library), more news on tests of new laser diodes and photodiodes by engineering students Evan Moore and Josh Gage, and on the 144 MHz transcevers (Raveon and Radiometrix). UVic has now signed the FAST grant forms from CSA, and sent them back to CSA for finalization. More discussion items for tomorrow's telecon include: flight/telescope plans and tests; construction and lab 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. I'll send a progress report before the telecon tomorrow.

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 - 2020-07-09

Hi all,

Apologies for the delay! -- here's an update on recent ALTAIR balloon work, and a reminder of the telecon in 45 minutes(!) from now:

We finally reached success on updating AIFCOMSS (https://github.com/ProjectALTAIR/AIFCOMSSwithCUPredictorTest) from the old Python 2.7 to Python 3 (specifically Python 3.7.6, within the most recent 2020 version of Anaconda 3) -- it now works well and gives a good flight path prediction on both MacOS and Linux, and two students (Spencer Plovie and Helio Huet) are presently testing out this update on Windows. Once Windows functionality is also confirmed, I will update the AIFCOMSS GitHub repository with the new code. (It requires the most recent tag of the Pydap library, which is only available on the Pydap GitHub repository, not in PyPI (the Python package index), so one needs the special command pip install git+https://github.com/pydap/pydap.git@fc0dd0e6f180e455dbb68a06a85f84b1eca6754f rather than a usual pip install of a package version from PyPI, in order to install that particular package.)

Engineering student Evan Moore is working on an updated version of the low-noise transimpedance amplifier circuit for both ALTAIR and ORCASat (to further reduce noise in that circuit). You can see a recent version of Evan's schematic here:

Evan is now working on the new board layout (and on new RF shielding for the board).

Radiometrix has our four SHX1-144 transceiver modules (they arrived there on Apr. 6) and is doing their firmware update that solves the BUSY output issue. They'll then test them out and send them back to us. Due to the COVID-19 situation in the UK, they've been taking a while. Very fortunately, the COVID situation is slowly starting to improve in the UK (although everyone is of course very wary of a likely second wave), and thus I'll ask them about this again soon. We've also been doing more connecting up and testing out of our two new 144 MHz Raveon M8S data modem transceivers here in Victoria:

After checking them out with Raveon's Windows-based Radio Manager software, I've started to connect the radios up to Arduino Megas -- in the next few weeks I'm planning to get them talking to one another, and then I'll check out their effective ranges.

Once we get those 144 MHz transceivers settled and back into the ALTAIR gondola, we'll do some outdoor drop testing of the actual gondola. (We've done all the outdoor drop tests I can think of doing with our dummy gondola.)

Since there exist a couple of miniature lightweight low-cost atmospheric aerosol particle size sensors that one can purchase and that could easily fit within our balloon gondola, for example the Alphasense OPC-R1: http://www.alphasense.com/WEB1213/wp-content/uploads/2019/08/OPC-R1.pdf and the DFRobot SEN0177: https://www.dfrobot.com/product-1272.html , I asked Liviu Ivanescu at Sherbrooke which of those sensors he would suggest we might possibly add to our payload, as having the additional info from such a sensor could potentially be quite useful to us. Liviu suggested we might try the DFRobot SEN0177, thus I'll purchase one of those -- they are nice and cheap, only $46.90 USD -- and test this aerosol particle size distribution sensor out here on the ground. That sensor is now ordered from DFRobot and is on the way here from China, and should be arriving around the end of next week.

UVic has completed signing the FAST grant forms from CSA, and the forms have been sent back to CSA for their finalization.

Engineering students Josh Gage and Evan Moore found that the "wings" that Josh had found in the laser diode light output distributions:

were due to how the diode was mounted in the heat sink. When the diode is mounted properly and carefully, the wings go away.

We also have our 10 Hamamatsu S12698-01 photodiodes and 3 Thorlabs FDS100-NOCAN photodiodes (those Thorlabs ones have their windows removed) here in Victoria:

I've given them to Evan Moore to try out -- he's taking a few weeks to ramp up, and will produce some linearity, etc., plots from them soon.

The survey-tripod-mounted device to cross-check yaw-pitch-roll information from the gondola (e.g., on days before/after flights) is also 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.

Next grant application will be a NATO "Science for Peace and Security" application (together with Australian colleague partners).

Our next telecon is in 45 minutes from now -- see below for Skype instructions.

Cheers, talk in 45 mins from now -- thanks all!


-- jalbert - 2020-07-09

Title Telecon tomorrow (Thursday) @ 5 pm Eastern time
Forum ForumGeneral
Topic attachments
I Attachment History Action Size Date Who Comment
PDFpdf EvanMooreTIAmplifier_RevA1.PDF r1 manage 7509.0 K 2020-07-09 - 21:59 JustinAlbert Draft schematic of a new update of the ORCASat (and ALTAIR) transimpedence amplifier circuit from engineering student Evan Moore
Edit | Attach | Watch | Print version | History: r1 | Backlinks | Raw View | WYSIWYG | More topic actions
Topic revision: r1 - 2020-07-09 - JustinAlbert
    • Cern Search Icon Cern Search
    • TWiki Search Icon TWiki Search
    • Google Search Icon Google Search

    Altair/Forum All webs login

This site is powered by the TWiki collaboration platform Powered by PerlCopyright & 2008-2023 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
or Ideas, requests, problems regarding TWiki? use Discourse or Send feedback