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Telecon tomorrow (Thursday) @ 5 pm Eastern time

Hi all!

Telecon tomorrow (Mar. 8 in North America, Mar. 9 in Australia) at the regular time: 5 pm Eastern (2 pm Pacific, noon Hawaii, 23.00 European, 9 am Eastern Australia). Lots more done in the past 2 weeks! -- I'll send a report this evening. Discussion items 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 / the new 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). 4) If there is any trouble, or if you don't get a Skype-call for some reason and would like to join, just send me an e-mail (jalbert@uvic.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 new flight control and simulation progress. VI) Grant applications VII) AOB

Talk to you all tomorrow, thanks!

justin

-- jalbert - 2018-03-07

Hi all!

Here's the minutes of our last telecon (attended by Arnold Gaertner (NRC) and me) and quick rundown of ALTAIR work done over the past 2 weeks -- my apologies for the delay! -- please just reply with (or let me know) any corrections -- thanks! :

Two weeks ago, I reassembled ALTAIR with its new epoxy-and-fibreglass-strengthened central axle ends:

and other needed improvements that were made and mentioned in the minutes from 2 weeks ago. Afzal Suleman happened to mention to me that our standard typical duct tape wrapping of ALTAIR post-assembly did not seem very professional, so it would be better to have a proper skin. (And additionally, it uses up nearly a whole roll of duct tape every time ALTAIR was wrapped, which is more than a bit wasteful and will get expensive.) So, I made a proper, reusable and easily removable, fabric-and-velcro outer covering for ALTAIR. (This was a somewhat interesting interlude of "dressmaking" from the typical sawing, drilling, and soldering of ALTAIR hardware work.) I think I ended up doing an OK job (considering that this was the first time that I had ever made a dress):

I then set up ALTAIR for another cutdown test yesterday:

and did the cutdown test last night. Unfortunately, the cutdown string snagged during the cutdown test, as can be seen in this 2-minute movie of this problematic cutdown:

https://wiki.heprc.uvic.ca/twiki/pub/Forum/ForumGeneral0005/ALTAIRFailedCutdownVideo_7mar18.MOV

and this followup movie of me tapping the string snag with a stick -- and thus getting the cutdown to complete:

https://wiki.heprc.uvic.ca/twiki/pub/Forum/ForumGeneral0005/ALTAIRFailedCutdownVideo2_7mar18.MOV

That string snag is most certainly and definitely a problem that we'd need to avoid happening in a real flight. I think that: a) I know how to set up the cutdown string to avoid such a snag happing in the future, and b) in a real flight, there would probably be enough motion of the payload to un-snag such a string snag during the flight itself, but I most certainly and definitely need to test a), and not depend on b) being the case. So I'll be doing another cutdown test tonight or tomorrow, to try to test a).

Students Alexy Decrooq and Kyle Jordan, as well as software expert Layth Holubeshen, have excellently completed getting the code that runs the balloon flight path predictor running inside of AIFCOMSS:

into better shape such that it is much easier to install, and they have also completed relatively easy and reproducible instructions on how to install it (on Windows and Linux platforms). We have now added those instructions as a README at https://github.com/ProjectALTAIR/AIFCOMSSwithCUPredictorTest. The next task is for me to add MacOS instructions to those excellent Linux and Windows instructions, and then to work on updating and improving the flight prediction code itself -- and also, after that, see if we can successfully simulate some form of station-keeping over a region of land, using the actual wind forecasts and data from NOAA, and also reasonable values for drag, propulsive thrust, battery power (as well as some battery recharging with future lightweight solar panels), etc etc.

Machinist Chris Secord has finally finished, and powder-coated, the 12" diameter aluminum sphere that will function as our pre- and post-flight photometry cross-check device, and here's the result of his work:

I then blackened the interior of the neck (and the interiors of each of the mini-necks for each of the four photodiode monitors):

It is now all ready for us to use our Avian-B paint to paint over the powder coat (Avian-B sticks far better over a powder coat than directly on aluminum, since Avian-B does not contain etch primer). The sphere should thus be coated and fully completed in the next couple of weeks!

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 application 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 new usual 5:00 pm Eastern time.

Cheers, talk to you all now!!!

justin

-- jalbert - 2018-03-08

Hi all!

Apologies for those late minutes that you just got about 30 minutes ago: they had been posted yesterday afternoon, but hadn't been e-mailed because of a small bug in the e-mailing cronjob, which our computing expert (Colin Leavett-Brown) just fixed.

Anyway, a small update from yesterday: this afternoon I did another cutdown test, with the revised cutdown string arrangement, which was successful (no caught cutdown string this time). Here's the 2-minute video:

https://wiki.heprc.uvic.ca/twiki/pub/Forum/ForumGeneral0005/ALTAIRSuccessCutdownVideo_9mar18.MOV

The important message is: the the cutdown string should always be arranged as in the following picture:

i.e. with the string pass-through loops nearby, but not ever butted-up against, the black plastic cutdown block. Doing that should prevent a snagged cutdown string during cutdown, such as occurred in the cutdown test the day before yesterday.

Thanks all!

justin

-- jalbert - 2018-03-10

DiscussionTopicForm
Title Telecon tomorrow (Thursday) @ 5 pm Eastern time
Forum ForumGeneral
Topic attachments
I Attachment History Action Size Date Who Comment
JPEGjpg ALTAIRCorrectCutdownStringArrangement.jpg r1 manage 1205.7 K 2018-03-10 - 01:39 UnknownUser Correct arrangement of ALTAIR cutdown string (string pass-through loops should be near, but not butted-up against, the black plastic cutdown block)
JPEGJPG ALTAIRDressmaking1.JPG r1 manage 1974.4 K 2018-03-08 - 05:59 UnknownUser making a fabric + velcro outer covering for ALTAIR, photo #1
JPEGjpg ALTAIRDressmaking2.jpg r1 manage 2223.0 K 2018-03-08 - 05:59 UnknownUser making a fabric + velcro outer covering for ALTAIR, photo #2
JPEGjpg ALTAIRDressmaking3.jpg r1 manage 2698.1 K 2018-03-08 - 06:00 UnknownUser making a fabric + velcro outer covering for ALTAIR, photo #3
JPEGjpg ALTAIRDressmaking4.jpg r1 manage 2676.0 K 2018-03-08 - 06:00 UnknownUser making a fabric + velcro outer covering for ALTAIR, photo #4
Quicktime movieMOV ALTAIRFailedCutdownVideo2_7mar18.MOV r1 manage 2630.4 K 2018-03-08 - 05:57 UnknownUser part 2 of video of problematic cutdown
Quicktime movieMOV ALTAIRFailedCutdownVideo_7mar18.MOV r1 manage 14168.6 K 2018-03-08 - 05:57 UnknownUser video of problematic cutdown
JPEGjpg ALTAIRPostDressmakingCutdownReady.jpg r1 manage 2093.0 K 2018-03-08 - 06:03 UnknownUser ALTAIR, in its new dress, ready for cutdown
Quicktime movieMOV ALTAIRSuccessCutdownVideo_9mar18.MOV r1 manage 10432.2 K 2018-03-10 - 01:34 UnknownUser video of successful cutdown (with correct arrangement of cutdown string)
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Topic revision: r7 - 2018-03-22 - jalbert
 
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