Here are minutes of our telecon on Tuesday May 16, 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) and me
After a succession of failed attempts, I finally got the 8" Celestron telescopes on the roof of the Bob Wright building at UVic to receive tracking commands from my Mac laptop, so that we will be able to use one of them as a tracking astrograph for ALTAIR when we do a flight. Here's a video of me finally getting the telescope to move on my laptop's command:
https://particle.phys.uvic.ca/~jalbert/CelestronSerialControlMovie.MOV
The secret was that the input commands (per Celestron's format) must be via the telescope control handset input telephone jack port, but _not_ via unplugging the control handset and providing the required RS-232 signals through that telephone jack port, but rather by inputting them through the little hidden telephone jack plug on the bottom back of the control handset itself. Anyway, works now, very thankfully!
In order to implement that control, I've put a software hook into AIFCOMSS for turning on and off telescope tracking, which you can see in the "Start Telescope ALTAIR Tracking" button on the right-hand side of the lower panel of AIFCOMSS:
http://projectaltair.org/HyperNews/get/AUX/2017/05/30/00.21-49311-MSSScreenshot_29may17.png
Currently, when that button is pressed, it changes to read "Stop Telescope ALTAIR Tracking," and starts issuing a command once every 5 seconds to the telescope to go to an alt-az of 45 degrees - 0 degrees (and those commands can be stopped at any time by pushing the same button). Now I need to implement the algorithm for calculating the proper alt-az, given the GPS positions of the telescope and of ALTAIR, in the software. That just requires my translating Yorke et al's tracking code for the Meade telescope, which Yorke very kindly gave to me last year, into Javascript so that AIFCOMSS can interpret it. That's a software task that can fortunately be done while I'm here at CERN for the next couple weeks (as it doesn't require one to be next to the hardware).
The other next main step -- trying some long-range telemetry tests -- will need to wait until I get back to Victoria on June 15 (just btw, on the way back from CERN, I'll be stopping in New Hampshire from June 11 - 14 to pick up some new little bits of equipment). I've been making hardware and software fixes to the Capella ground station and Betelgeuse test box, as well as making a new second ground station (similar to Capella, but with our larger [~1.5 meter long, 14 dBi] Yagi antenna, rather than Capella's ~0.6 m, 9 dBi antenna) named Deneb. A photo of the Deneb transceiver box (attached to the Capella antenna, for testing purposes) and ALTAIR-Victoria hanging up in my office, with Betelgeuse and the Capella transceiver box on the windowsill in the background, is at:
http://projectaltair.org/HyperNews/get/AUX/2017/05/15/17.47-9252-etelgeuseCapellaDeneb.jpg
Deneb and Capella both appear to work well now, and we'll be able to do outdoor long-range tests just as soon as I get back to Victoria.
The ALTAIR-Victoria payload is fully assembled, and the light sources are functioning nominally:
http://projectaltair.org/HyperNews/get/AUX/2017/04/17/18.41-75359-assembledpayload1.JPG http://projectaltair.org/HyperNews/get/AUX/2017/04/17/18.41-60505-assembledpayload5.JPG http://projectaltair.org/HyperNews/get/AUX/2017/04/17/18.41-7025-assembledpayload6.JPG http://projectaltair.org/HyperNews/get/AUX/2017/04/17/18.41-70408-assembledpayload7.JPG
However: only the light sources themselves have been tested so far -- they need to be tested in concert with the photodiode readout; with the telemetry; 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, long-range telemetry testing, etc. -- before seriously thinking about a flight ...
We're also now starting to work on adding ALTAIR flight path predictions to AIFCOMSS. The code for that will be based on Cambridge University's balloon flight prediction code, which is open source -- see: https://github.com/jonsowman/cusf-standalone-predictor and http://predict.habhub.org . That CU code does not incorporate any propulsion, though, of course (nor an ability to bleed helium, nor of course is it integrated at all yet with AIFCOMSS, or Javascript for that matter).
Student Nick Hammar, Karun, and I successfully transmitted GPS data from the Betelgeuse test box on top of the roof of the Elliott Bldg. here, to the Capella ground station on top of the Bob Wright Bldg. about 100 m away, when transmitting at the default 10 mW output power of the DNT transceiver (i.e. 100 times lower power than the 1 W of which the DNT is capable). Transmission worked multiple times, but it did cut out occasionally (and require a radio reset each time): the connection was not nearly as rock-solid as I would have liked to see. We'll work on that issue and see if it is due to unavoidable multipath interference (perhaps from the metal parapets around the Bob Wright roof), or from something that is fixable. Following that, the next step is to transmit from the DAO (12 km away) to the Bob Wright roof, and GPS-track a terrestrial light source at the DAO using one of the Celestron telescopes on top of Bob Wright.
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. Mark is now working on some carabiner-type attachments for the end of the pole, and he should have those finished in about a week or so.
Recent progress also on the hardware for the pre- and post-flight photometry cross-check device -- the 12" aluminum sphere (a photo of it is attached in a link at the bottom of this message, http://www.sharpeproducts.com/store/aluminum-12-dia-sphere) is now been cut into two hemispheres, with holes for four measurement photodiodes:
http://projectaltair.org/HyperNews/get/AUX/2016/12/19/15.28-19075-Hemispheres1.jpg http://projectaltair.org/HyperNews/get/AUX/2016/12/19/15.28-5015-Hemispheres2.jpg
Machinist Chris Secord still needs to cut the large light-entrance port in the top of the first hemisphere, and then we need to paint the interior of both sides with Avian-B paint (after first priming the interior with white powder coat). He's finally gotten a chance to do that work, and it should be coated and completed when I get back to Victoria June 15.
The survey-tripod-mounted device to cross-check yaw-pitch-roll information from the gondola (e.g., on days before/after flights) is mostly 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 a 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 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 establish telemetry communication between ALTAIR-Victoria:
http://projectaltair.org/HyperNews/get/AUX/2017/04/17/18.41-75359-assembledpayload1.JPG
and the Betelgeuse test-box:
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
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 4 pm Eastern time **.
Cheers, talk to you all tomorrow! justin
On Mon, 15 May 2017 23:28:10 GMT, Justin Albert wrote:
> Hi! > > Telecon tomorrow (May 16 in North America, May 17 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/2016/08/17/20.30-32651-ectronicsBoard17aug16.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
