Here are minutes of our telecon on Tuesday Aug. 22, my apologies for the delay! -- as well as work done since then -- please just reply with (or let me know) any corrections -- thanks! :
Attendees: Arnold Gaertner (NRC) & me
The cutdown servo motor is now properly controlled by the main board, and one can now command the cutdown servo remotely via a ground station. The navigation mast (with GPS, orientation [accel+gyro+mag], and environmental [temp+pres+hum] sensors) that sits on top of the gondola is also now successfully transmitting all its data to the ALTAIR-Victoria main board, via the 100 kHz I2C bus, as can be seen in the following photo:
http://projectaltair.org/HyperNews/get/AUX/2017/09/04/21.31-15826-ndowGettingGPSreading.jpg
and brief movie:
https://particle.phys.uvic.ca/~jalbert/ALTAIRtransmittingGPSdata.MOV
Much time was spent debugging some mysterious I2C bus lockup freezes, which only occur when ALTAIR-Victoria is self-controlled (i.e., when it does not have its USB port cable-connected to a computer), and that go away when debugging info is added to its serial output. Thus, I have "permanently" added the debugging info to the serial output in the main loop, and (until/unless they happen again) meanwhile moved on to the next step, which is to utilize the remote cutdown servo transmission to release the rigging (rather than it just moving the servo motor itself), and to use the rigging release to properly/permanently place the navigation mast in a very good location on the top of the gondola -- currently the mast is just affixed there via a tiny C-clamp -- because we definitely don't want the placement of the navigation mast to interfere with the cutdown rigging release (i.e., to have that rigging catch on the mast during cutdown, and thus have the gondola remain attached to the balloon after cutdown, via hanging on to the rigging from its navigation mast). So we should definitely put the mast in a good spot. (And yes, it should also break away if the rigging were to catch on it, however then we would lose all of those sensors on the mast, so that's not the most wonderful fallback.) Thus, here is a photo of ALTAIR-Victoria (at bottom of photo) in its current location below the cutdown setup down in the lab:
http://projectaltair.org/HyperNews/get/AUX/2017/09/04/21.31-73365-paringForCutdownSetup.jpg ,
ready for its ground station-controlled cutdown testing (and mast placement).
Students Alexy Decrooq and Kyle Jordan, as well as software expert Layth Holubeshen, are all working on getting the code that runs the balloon flight path predictor running inside of AIFCOMSS:
http://projectaltair.org/HyperNews/get/AUX/2017/07/10/18.55-39312-IFCOMSSwithPredictor1.png http://projectaltair.org/HyperNews/get/AUX/2017/07/10/18.55-56749-IFCOMSSwithPredictor2.png
into good shape such that it is easier to install, and additionally working on relatively easy and reproducible instructions on how to install it (on Windows, Mac, and Linux platforms). We're greatly looking forward to adding those instructions as a README at https://github.com/ProjectALTAIR/AIFCOMSSwithCUPredictorTest, as well as making any changes to the code itself to make it easier to install. After that's done, we will work on updating and improving the flight prediction code itself -- and also, after that, seeing 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 been very busy welding 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:
http://projectaltair.org/HyperNews/get/AUX/2017/08/21/19.38-86577-WeldedSphere.jpg
He still needs to tack-weld the bottom support ring onto the bottom half of the sphere. When he finishes this weld job, we'll then prime the interior with white powder coat, and then 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 be coated and completed in the next couple of weeks. ALTAIR-Victoria is fully assembled, and its light sources are functioning nominally:
http://projectaltair.org/HyperNews/get/AUX/2017/06/26/19.25-55880-ALTAIRwithGear.JPG
however: only the light sources themselves, plus the basic telemetry, have been tested so far -- they both need to be tested in concert with the photodiode readout; with the orientation, GPS, and environmental monitoring; with the onboard data storage; with the propulsion and its monitoring data; etc., etc., etc. Much of the software to combine all that functionality, and resultantly _very_ large number of possible error conditions, still needs to be written. Thus, there remains an enormous amount to do -- including, of course, drop testing, more long-range telemetry testing, etc. -- before seriously thinking about a flight ...
Mark Lenckowski has completed the stabilized pole for the new 10-meter-high drop test setup at Victoria:
http://projectaltair.org/HyperNews/get/AUX/2016/12/19/15.28-91194-MeterStabilizedPole_1.jpg http://projectaltair.org/HyperNews/get/AUX/2016/12/19/15.28-81425-MeterStabilizedPole_2.jpg
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:
http://projectaltair.org/HyperNews/get/AUX/2016/08/31/18.15-24048-wPitchRollCalibDevice.jpg
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 feet 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 more data information to the telemetry communication between ALTAIR-Victoria:
http://projectaltair.org/HyperNews/get/AUX/2017/04/17/18.41-75359-assembledpayload1.JPG
and the Capella ground station:
http://projectaltair.org/HyperNews/get/AUX/2017/01/23/21.17-37945-Capella.jpg
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 tomorrow, at the usual 4:00 pm Eastern time.
Cheers, talk to you all tomorrow! justin
On Mon, 21 Aug 2017 23:10:23 GMT, Justin Albert wrote:
> Hi! > > Hope those of you who were able had a chance to see the eclipse today! > Telecon tomorrow (Aug. 22 in North America, Aug. 23 in Australia) at the > regular time: 4:00 pm Eastern (1:00 pm Pacific, 10 am Hawaii, 22.00 > European, 6 am Eastern Australia). 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; 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 (4 pm Eastern, 1 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) Nanosat solid models & Houman's thesis > V) Computing/website, including new flight control and simulation progress. > VI) Grant applications > VII) AOB > > Talk to you all tomorrow, thanks! > justin
Attachments:
http://projectaltair.org/HyperNews/get/AUX/2016/05/22/18.23-24702-12inAlSphere.jpg
http://projectaltair.org/HyperNews/get/AUX/2016/04/06/16.53-58615-SideView.pdf
http://projectaltair.org/HyperNews/get/AUX/2016/04/06/16.53-48539-TopView.pdf
http://projectaltair.org/HyperNews/get/AUX/2017/06/26/19.25-55880-ALTAIRwithGear.JPG
http://projectaltair.org/HyperNews/get/AUX/2016/08/17/20.30-99000-AvianBTestHemisphere.jpg
http://projectaltair.org/HyperNews/get/AUX/2016/08/17/20.30-68004-Betelgeuse1.jpg
http://projectaltair.org/HyperNews/get/AUX/2016/08/17/20.30-53104-Betelgeuse2.jpg
