Telecon tomorrow (Thursday) @ 5 pm Eastern time

Hi all,

Telecon tomorrow (Aug. 19 in North America, Aug. 20 in Australia) at the regular time: 5 pm Eastern (2 pm Pacific, 11 am Hawaii, 23.00 European, 7 am Eastern Australia). Continued progress from Andrew Macdonald on layout for the new ALTAIR form-factor version of the ORCASat transimpedance amp board (plus a new little clock board); and we also have further updates to AIFCOMSS. Progress also continues to be made on optical simulation and on measuring electrical characteristics of the photodiode readout. 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 - 2021-08-19

Hi all,

My apologies for the delay! -- here's an update on recent ALTAIR balloon work, minutes of the last meeting on August 5 (attendees Arnold Gaertner [NRC] and me), and a reminder of the telecon in 15 minutes(!) from now:

Andrew Macdonald has made more progress on the layout of the ALTAIR version of the photodiode readout / transimpedance amplifier board -- and is also now designing a small separate clock signal distribution board, for producing and distributing the clock signal to the three photodiode readout / transimpedance amplifier boards. Here is the most recent version of his schematic for the photodiode readout / transimpedance amplifier boards:

The clock signal comes in from the clock signal distribution board through the MMCX connector shown in the lower part of the first page of the schematic, and is also passed through onto the stacking connector shown on the right-hand side of the first page of the schematic. Hopefully Andrew will have completed layout files for us for the next telecon, and we can finally make these boards (and then he can test them)!

Summer students Colton Broughton, Sarah Alshamaily, and Will Stokes have completed installing AIFCOMSS ( https://github.com/ProjectALTAIR/AIFCOMSSwithCUPredictorTest ) on their laptops. I've updated AIFCOMSS to work with the recent Cesium v1.83, as well as the instructions, and they all report success with this update and those instructions. The next two things that we know most definitely will need updating (or, rather, creating) are the station-keeping software for AIFCOMSS, and the online command-handling within the onboard Arduino software -- and I'll be working on those over the next 2 weeks.

I still need to test out out Radiometrix SHX1 144 MHz transceiver modules that were returned to us from Radiometrix (following their firmware update to fix the BUSY output):

as well as our two 144 MHz Raveon M8S data modem transceivers:

Once we get our 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.)

And we also still need to test out our new DFRobot SEN0177 payload aerosol monitors that we have here:

I've begun to look some more at MEEP (https://meep.readthedocs.io/en/latest/) for finite-difference time domain (FDTD) simulation of integrating sphere output, but I haven't yet had time to make any significant progress there -- I'm hoping to do that in the next couple of weeks. It will be interesting to compare that with ray tracing simulations, when I can get a chance to do that!

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 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 15 minutes from now -- see below for Skype instructions.

Cheers, talk in 15 mins (!) from now -- thanks all!

justin

-- jalbert - 2021-08-19