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Telecon tomorrow (Thursday) @ 5 pm Eastern time

Hi all!

Telecon tomorrow (Sept. 6 in North America, Sept. 7 in Australia) at the regular time: 5 pm Eastern (2 pm Pacific, noon Hawaii, 23.00 European, 7 am Eastern Australia). More progress on the photodiode precision amplifier board construction, updates on station-keeping prediction and simulation software, on the pre- and post-flight cross-calibration integrating sphere, and on the windowless photodiode orders from Hamamatsu and OSI Optoelectronics -- I'll post a summary shortly. 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 forms of tests of the new gondolas and payloads here in Victoria

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 - 2018-09-06

Hi all!

Here's a quick progress report on ALTAIR balloon work done over the past two weeks, plus the minutes of our last telecon (attended by Arnold Gaertner (NRC) and me) -- my apologies for the delay! -- please just reply with (or let me know) any corrections -- thanks! :

We're sending out version 5 of the design of our inflight precision photodiode amplifier board, from Andrew Macdonald in the UVic phys & astro electronics shop, for fabrication (of 3 small boards containing this schematic -- one little board for each of the 2 photodiodes on the integrating sphere, and a third little board for the photodiode on the diffusive LED light source). We got some useful comments from the NIST folks on last week's v.4 design, and this version 5 for fabrication is the update in response to them:

Our 11 windowless Hamamatsu S2386-8K photodiodes should be arriving at the Stubbs Lab at Harvard in late September, and then I'll carry our share of them up to Canada at the end of the year. Last week, OSI Optoelectronics promised to send us a quote for our windowless UV-015 photodiodes (as the secondary cross-check photodiode on the integrating sphere) ASAP, so we are hoping for that from them within a week or so.

With the modifications to the ALTAIR legs it is now easier to remove and re-install the shock-absorbing wheels for the pre- and post-flight photometry cross-check with the integrating sphere:

however the easiest and best thing would just be to rest the payload on top of the sphere without having to take off the wheels beforehand and replace them afterwards. Thus, we are modifying the sphere, via making some cuts to the lip of the sphere, to be able to do exactly that:

The cuts that Chris Secord will be making this afternoon to allow the payload to just be rested on top of the sphere are shown in black pen on the black upper surface of the mating flange lip on the integrating sphere in the above photo. Right after that, I will use a long Q-tip to add some Avian-B white coating to the internal seam in the integrating sphere (which you can see in the below image):

just in order to white-out that seam, and then install the photodiodes after that.

Software-wise, we are working on the very time- and testing-intensive task of taking the spaghetti code that is the current firmware loaded onto the ALTAIR main board, and turning that into a proper object-oriented structure, so that we can then flexibly adjust (and add to!) the telemetry information that ALTAIR sends down to the ground station(s). That is presently being updated in https://github.com/ProjectALTAIR/ALTAIROnboardArduinoSoftware/tree/master/libraries .

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.

Another next step, software-wise, is to add a bunch of additional data information to the telemetry communication between ALTAIR-Victoria:

and the Capella ground station:

and to update the control and monitoring software to incorporate the telemetered info, and also implement onboard SD card data storage, as well as storage of the telemetered info.

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.

That's all I remember, please send things that I forgot. Next telecon * NOW!!! *, at our usual 5:00 pm Eastern time.

Cheers, talk to you all now -- thanks all!!!!!


-- jalbert - 2018-09-06

Title Telecon tomorrow (Thursday) @ 5 pm Eastern time
Forum ForumGeneral
Topic attachments
I Attachment History Action Size Date Who Comment
JPEGjpg ALTAIR_IntegratingSphereLipCutsToMake.jpg r1 manage 1957.0 K 2018-09-06 - 21:14 JustinAlbert ALTAIR integrating sphere lip saw cuts to make
PDFpdf PDAnalogFrontendV5.pdf r1 manage 74.0 K 2018-09-06 - 20:15 JustinAlbert Version 5 of the photodiode frontend amplifier board schematic
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Topic revision: r3 - 2018-09-07 - JustinAlbert
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