Apparently everyone was rushing to get other end-of-term-type things done during our telecon time on Apr. 18 -- as I was the only one on Skype then! -- but a bunch of stuff was done in the past 2 weeks, so below is a run-down on that:
A large chunk of the past two weeks was spent remaking the helium bleed valve that will close off the balloon neck (plus support the rigging and gondola). The bleed valve that was made and tested last year:
http://projectaltair.org/HyperNews/get/AUX/2016/12/05/17.35-76064-HeliumBleedValve.jpg
still had urethane foam around its fitting (from when a leak check was done using water from a hose), and did not have a seal to mate with a balloon neck. To fix that, I got a new Valterra valve (they are only $15), re-installed the servo, and installed a seal to mate with balloon necks. One significant issue is that our balloon necks have dramatically different sizes: Kaymont balloons have fairly large necks (about 4" or 5" diameter), whereas the Chinese-made / Hwoyee / scientificsales.com balloons have much smaller necks (about 2" diameter). Fittings/seals that work for one type, do not work well at all for the other. I made a device that could stretch the necks of the small-neck balloons around a larger fitting:
http://projectaltair.org/HyperNews/get/AUX/2017/05/01/18.03-71833-MrPinchy.jpg
but I did not like the result at all -- the device (named "Mr. Pinchy") could potentially snap right down like a rat trap upon one's fingers, just as one was working to stretch the very small balloon neck around the very large valve fitting. Not a good thing to have happen in the field before a launch. Thus, I consigned Mr. Pinchy to the recycle bin, and made two different valve fittings, one for smaller necks and one for larger necks:
http://projectaltair.org/HyperNews/get/AUX/2017/05/01/18.03-86563-ValveNeckFittings.jpg
Each fitting needs to have its own pressure+temp+humidity sensor and feedthrough, but that is OK -- those sensors are only $30.
The ALTAIR-Victoria payload is now 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
Here it is upstairs (together with ground station Capella, and text box Betelgeuse) for testing in my office:
http://projectaltair.org/HyperNews/get/AUX/2017/04/17/18.41-49980-assembledpayload2.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 even seriously thinking about a flight ...
The AIFCOMSS monitoring and control software now has altitude and time sliders for winds at different altitudes, and wind forecast and recent history, respectively, thanks to Layth Holubeshen. The latest screenshot can be seen at:
http://projectaltair.org/HyperNews/get/AUX/2017/04/17/18.41-79055-MSSScreenshot_17apr17.png
The next step for that software is to get wind speed and direction text (at ALTAIR's altitude) into the Windytv window text box. And, after that, to work on adding ALTAIR flight path predictions.
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 8" 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). It should be coated and completed in approximately another month.
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.
Regarding the simulation part of AIFCOMSS, we'll be working on adding flight path prediction information to the Windytv and Cesium windows of AIFCOMSS, using GFS (global forecast system) file input for both forecast and real-time information of winds. 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, 17 Apr 2017 22:48:55 GMT, Justin Albert wrote:
> Hi all, > > Happy Easter and Passover, and hope you enjoyed your weekend. Telecon > tomorrow (Apr. 18 in North America, Apr. 19 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
