Telecon tomorrow (Thursday) @ 5 pm Eastern time

Hi all,

Telecon tomorrow (Aug. 15 in North America, Aug. 16 in Australia) at the regular time: 5 pm Eastern (2 pm Pacific, 11 am Hawaii, 23.00 European, 7 am Eastern Australia). The ALTAIR SHX144 telemetry is now working and integrated with the default DNT900 and second backup RFM23BP telemetry, we have updates on testing of the OSI and Hamamatsu photodiodes with the new amplifier boards, and also some more 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 gondola/payload; 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 an update with some recent photos, etc, 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 - 2019-08-15

Hi all!

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

I've been working (finally) on integrating the SHX1-144 144 MHz telemetry with the present ALTAIR telemetry that has only been using the DNT900 (910 MHz) as default and RFM23BP (440 MHz) as the single backup. The SHX1-144 is intended to be the first backup (the DNT900 will still be the default) and the RFM23BP will be demoted to second backup. This update of the telemetry is now sort of working, but I still most definitely have more to do: One issue is that (unlike the other two boards) the SHX board always reports that it is "busy" (even when there doesn't seem to be anything in its buffer, and it is perfectly willing to receive new commands), so I've had to at least temporarily bypass its busy check. Another issue (the one I'm currently working on) is that command-like strings mysteriously appear in the SHX buffer, even when I haven't sent them to it, and often these ghost-commands have deleterious effects (such as automatically switching the primary radio back to the DNT, after I've manually switched the primary status over to the SHX). Anyway I'm hoping that two weeks from now I'll be able to report that we have a bulletproof, doubly-backed-up telemetry system that can smoothly switch primary radio between any one of the three radios, and will smoothly and automatically failover to the backup radios if commands and keep-alives are not received on the primary, etc etc.

Student Peter Ogilvie continues to work on testing the OSI UV-015 photodiodes, that show the worrying nonlinearity at high optical power, when using a blue laser diode source rather than the red and NIR ones we've been using, and also testing them when they have their windows knocked out. Assuming the problem of the UV-015 nonlinearity at high optical power is not some sort of artifact -- which it shows no signs of being -- I've asked Hamamatsu for a quote for windowless S12698-01 photodiodes (which could perhaps be an alternative to the OSI UV-015), and Hamamatsu is working on a quote for those (it is probably taking Hamamatsu longer than expected because it requires them to make a new custom part number for it -- I'll check again with Hamamatsu in a week if they haven't sent it by then). Note that here we also still need to test the windowless Hamamatsu S2386-8K photodiodes that we presently have.

I'm also finally working with student Zejia Xu 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". We're developing some actual station keeping algorithms and will implement them in the code.

We're waiting for our lawyer to get back from vacation so that we can send the notification to the local municipality (Saanich, the Victoria suburb in which both my backyard and half of the UVic campus are located) regarding outdoor drop testing in my backyard, which has been bureaucratically held up because of the local height restriction bylaw issues mentioned in previous minutes ( https://wiki.heprc.uvic.ca/twiki/bin/view/Forum/ForumGeneral0032 ) -- we're hoping that this notification to Saanich will finally resolve that.

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 a new CSA FAST (due Oct. 18), a "New Frontiers in Research Fund" (NFRF -- LoI due Sept. 4, then application due Dec. 10), and a NATO "Science for Peace and Security" application, together with Australian colleague partners.

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

Cheers, talk in an hour from now! -- thanks all!

justin

-- jalbert - 2019-08-15