Discussion Forum » General »

Telecon tomorrow (Thursday) @ 5 pm Eastern time

Hi all,

Telecon tomorrow (Dec. 5 in North America, Dec. 6 in Australia) at the regular time: 5 pm Eastern (2 pm Pacific, 11 am Hawaii, 23.00 European, 9 am Eastern Australia). New (and successful) drop test results with test spars added to the parafoil (and real spars ordered), updates on telemetry, on testing of the windowless Hamamatsu photodiodes with the new amplifier boards and new equipment received from Thorlabs, and on progress on AIFCOMSS station-keeping prediction/simulation software. 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
VII) AOB

Talk to you all tomorrow, thanks!!!
justin

-- jalbert - 2019-12-04

Hi all!

Apologies for the delay! -- here's a quick update on ALTAIR balloon work over the past 2 weeks, minutes of the telecon 2 weeks ago (attendees Arnold Gaertner [NRC] and me), and a reminder of the telecon in 25 minutes(!!!) from now:

Last Wednesday I picked the parafoil up from Nahid Tailoring Services, who had sewn the fabric "belt loops" and "end stops" for spar attachment onto it, and they did a decent job -- here are a couple of photos (with the test spars inserted through the loops):

So, it was ready for new drop tests with the test spars in place. I did three such new drop tests with these test spars (one on Sunday and two on Monday). Here are the videos of the three new drop tests:

These spars are definitely an improvement, in that the parafoil doesn't fail to open when these test spars are in place, but as you can see, there is still lots of room for more improvement in that the test spars on the two far ends of the parafoil are not connected with the main spar that runs the length of the parafoil -- and that fact tends to cause the ends of the parafoil to flop inward.

I think we can fix that problem by, instead of having 3 separate spars, having a single spar that arcs through all the belt loops, and thus keeps the ends of the parafoil pushed outward. The parafoil is 120" x 39" in size, so a single 16-foot-long thin fiberglass spar might be a hard thing to find. But we can get around that issue -- by inserting the ends of the 10-foot-long thin (1/8" diam.) fiberglass spars that I ordered on Tuesday: https://www.mcmaster.com/8543k31 -- into two 3' lengths of the 1/4" diam nylon test spar material that I have so far been using for the main test spar. (I ordered 4 of those 10-foot-long 1/8" diam fiberglass spars from McMaster-Carr for $5.83 each = $23.32, and McMaster-Carr then added over $200 in shipping charges to the order!!!) Those fiberglass rods should arrive this coming Tuesday, and then I'll install them and do more drop testing on non-rainy day(s) later next week.

Radiometrix finally got back to me (after over 10 weeks of waiting for any sort of reply from them!!!) regarding the missing BUSY signal from their claimed BUSY output pin on the SHX1. They confirmed at indeed, at present, the BUSY output is not implemented in the board's firmware (so indeed it always reading 4 volts is the expected response, given that lack of implementation). They asked me "Can you please let us know what would you like the SHX1 BUSY function to be? 1) To indicate Modem is busy or its Transmit Buffer is full? 2) Receive Buffer full with Valid Data?" and I responded that "1) To indicate Modem is busy or its Transmit Buffer is full" is preferable, so hopefully sometime in the future they will reply with new firmware that would implement that option, and we can then upload that new firmware and try it out. But, in the meantime, the two new 144 MHz RV-M8S radio modem boards from Raveon (https://www.raveon.com/m8s-oem-data-radio-modem) have arrived in New Hampshire, and I'll pick them up over xmas, and then test them out first thing in the new year.

Student Peter Ogilvie is still working with the new Thorlabs equipment (12 extra standard FDS-100 photodiodes [with windows; and we will see if we can cleanly take a couple of the windows off with our WR1 can opener that we got this summer], three new laser diodes [a 980 nm wavelength L980P200, an 840 nm wavelength L840P200, and an extra 660 nm L660P120 laser diode], and some new laser diode driver ICs [MLD203P1, MLD203P2, MLD203CLN, MLD203P1E, and MLD203CLNE]).

We're working on the New Frontiers for Research (NFRF) application that is due on Dec. 10. Other applications, such as CSA FAST and NSERC, have been submitted and are under review (with results on those expected in March or April of 2020).

I'm also working with a new undergraduate student on the actual station-keeping algorithm for AIFCOMSS. Presently the "station keeping" code in AIFCOMSS just turns on the propellers in the simulation at full power, and propels the gondola in a single direction until the battery runs out (it's presently most certainly not actual "station keeping"). I added some hooks for adding actual station keeping algorithms into the code, and we're developing the algorithms and will implement them.

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 applications will be the NFRF application mentioned above (due Dec. 10!) and a NATO "Science for Peace and Security" application, the latter together with Australian colleague partners.

Our next telecon is in 25 minutes (!) from now (see below for Skype instructions).

Cheers, talk in 25 minutes(!!!) from now -- thanks all!

justin

-- jalbert - 2019-12-05

DiscussionTopicForm
Title Telecon tomorrow (Thursday) @ 5 pm Eastern time
Forum ForumGeneral
Topic attachments
I Attachment History Action Size Date Who Comment
Unknown file formatm4v ALTAIRDropTest2WithTestSparsCorrRigging2Dec19at145pm.m4v r1 manage 35026.9 K 2019-12-04 - 23:52 JustinAlbert Second drop test with (nylon+wood) test spars added to the parafoil (and first with rigging un-skewed). ~1:45 pm on Mon. Dec. 2, 2019.
Unknown file formatm4v ALTAIRDropTest3WithTestSparsReverRigging2Dec19at215pm.m4v r1 manage 40747.4 K 2019-12-04 - 23:53 JustinAlbert Third drop test with (nylon+wood) test spars added to the parafoil (done with rigging un-skewed, but reversed). ~2:15 pm on Mon. Dec. 2, 2019.
Unknown file formatm4v ALTAIRFirstDropTestWithTestSparsSun1Dec19at3pm.m4v r1 manage 21170.8 K 2019-12-04 - 23:51 JustinAlbert First drop test with (nylon+wood) test spars added to the parafoil. ~3 pm on Sun. Dec. 1. The rigging setup was slightly skewed in this drop test.
JPEGjpg ALTAIRParafoilNahidTailoringBeltLoops.JPG r1 manage 2660.1 K 2019-12-04 - 23:57 JustinAlbert "Belt loops" and "end stops" sewn on to the parafoil (by Nahid Tailoring Services here in Victoria) for addition of spars to the parafoil. Test spars (nylon & wood) inserted in this photo.
JPEGjpg ALTAIRParafoilNahidTailoringBeltLoopsDetail.JPG r1 manage 2479.9 K 2019-12-04 - 23:59 JustinAlbert Detail of "belt loops" sewn on to the parafoil (by Nahid Tailoring Services here in Victoria) for addition of spars to the parafoil.
Edit | Attach | Watch | Print version | History: r2 < r1 | Backlinks | Raw View | WYSIWYG | More topic actions
Topic revision: r2 - 2019-12-05 - 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