Here are minutes of our meetings on Thursdays Nov. 19 and Dec. 3 -- apologies for the long delay and combined minutes, 'tis finals season -- please just reply with (or let me know) any corrections -- thanks!:
Attendees: Yorke Brown (Dartmouth), Arnold Gaertner (NRC), Karun Thanjavur (UVic)
On Dec. 3, Yorke gave us an update on the ALTAIR Meade 12" telescope -- owned by Harvard -- for which the computer control and display (which controls, and monitors, the slewing and tracking motors on its alt-az mount), completely stopped functioning -- wouldn't boot -- a few days prior. Yorke had talked with Chris Stubbs, who said to talk to Meade, and send it in if necessary, and he would pay for its repair and shipping. Here's Yorke's summary of the Meade issue:
"I called Meade and the rep first wanted me to try to flash the firmware. That didn't work; I couldn't get the uploader software to talk to itsserver. Also, the rep convinced me to try swapping the handbox. So I borrowed a handbox from the observatory and, voila, it worked. So I tried our handbox. That worked, too. So I returned the borrowed one and went back to work figuring it was just a cable issue. It failed again Monday. Messed with the cable; no luck. Borrowed the handbox again. Still not working. So I'm back to the original diagnosis that the computer has some intermittent--but fatal--hardware problem. And that's where it stands today. I've been off campus the last couple of days working on other things. It does look like I'm going to need to ship the mount to Meade. The rep said they could send a new board, but he really thought I should ship it to them to work on."
Yorke has made very useful updates to his flight control software in the meantime.
While analyzing the data from the A15 flight late last month, I found the electronic gain information in the FITS headers of images from both that and previous observed flights, including A11 (my apologies for having missed that info before), which very likely explains the longstanding issue with the factor of 2 difference between the observed and the expected photometry in A11 -- that O(200%) discrepancy appears to now be just an O(20%) one (also with improvements of that order having been made between the 2013 A11 flight and now, which certainly bodes very well for future images) -- http://projectaltair.org/HyperNews/get/balloon/15/1.html If this were Moore's Law, then we'll be getting 0.2% photometry four years from now. ;) We can certainly hope ... and work very hard. As for photometry from the stars on the A15 images themselves (as well as on images from a followup "A15A" outing done by Yorke and Asher to take more stellar images) -- I'm still analyzing those.
We now have a few more little pieces of hardware in Hanover: 1) a new (second) SPOT Trace device -- which next week (on Dec. 17) Yorke and I will try flying "bare," just using a bunch of party balloons -- to test out the possibility of school classes (in U.S./Canada and/or in the developing world) doing the same in the future, in order to learn about winds at different atmospheric altitudes; 2) a new "dew shield" for the Meade telescope: http://www.amazon.com/gp/product/B001I3XF64?psc=1&redirect=true&ref_=oh_aui_detailpage_o04_s00 , to discourage condensation on the telescope of course ; and 3) some silver epoxy, for thermal connections. I will get there next week, on the evening of the 16th, and bring along with me to Hanover, a transmitter, receiver, and servo, so that we can test parafoil steering functionality on future dummy payload tethered balloon drop tests (likely this coming spring).
Karun has a copy of the diffusive light source which Yorke sent up from Hanover -- Karun is leading the development here at UVic of tripod-mounted devices to, in the field immediately before launch, and right after recovery, cross-check both photometry information, and yaw-pitch-roll information, from the ALTAIR gondola -- and having a copy of the diffusive light source is needed for the former. He is working with the machine shop (and the electronics shop) here to develop and construct those devices, which will be accurate & precise to 1% or so (note that photometry checks which will be more precise than that will be done in the lab, most precisely at NRC, and/or NIST -- however we want to have the ability to do quick cross-checks in the field immediately before and after flight). Karun is also now working with a sample microcontroller board (with Microchip PIC18F87J50 microcontroller -- circuit diagram attached) from the electronic shop here, to use for testing motor control for an ALTAIR motor and propulsion control microcontroller board we will be designing this term. He has now gotten the pulse width modulation code for it up and running -- video at
https://particle.phys.uvic.ca/~jalbert/MotorAndPropTests/IMG_2136.MOV
and now Karun has also solved the problem of simultaneous control of two propulsion motors, and of controlling a servo as well as propulsion motors. He's now working on monitoring the input from the on-chip A/D converters (which will be monitoring temperatures, motor RPM rates, and current flow). We just purchased a second little PIC microcontroller board: http://www.digikey.ca/product-search/en/programmers-development-systems/accessories/2621524?k=PIC18F97J94 with a more advanced version of the PIC18F87J50 -- the PIC18F97J94 -- so that we can test out that new one as well before we make our custom board with it. We also have the beginnings of a little mechanical test rig, the internals and externals of which can be found in the four attached photos, and in the following movie showing the lightweight but strong servo gearbox for rotation of the propulsion support axle:
https://particle.phys.uvic.ca/~jalbert/MotorAndPropTests/IMG_2145.MOV
When within ALTAIR, the motor and propulsion control microcontroller board will logic interface with Yorke's main board (in a similar way to how the present cutdown-motor control board interfaces with the main board. A separate propulsion battery will of course be carried.)
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.
We sent in our CSA FAST 2015 application in October, and the next one will be a NATO "Science for Peace and Security" application which will be due at the end of _January_.
That's all I remember, please send things that I forgot. Next telecon next week, on Thursday, Dec. 17, at 4 pm Eastern time.
cheers, thanks all! justin
On Thu, 03 Dec 2015 02:19:04 GMT, Justin Albert wrote:
> Hi! > > Telecon tomorrow (Dec. 3) at the usual time: 4:00 pm Eastern (1:00 pm > Pacific, 10:00 am Hawaii, 22.00 European). Discussion items include: > status and planning for flights in NH; telescope tests, and the Harvard > Meade telescope's failure to function over the past couple of days -- > tracking, alignment, calibration, and observation; 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) Status and flight planning > II) Telescope tests, and its current functionality (and lack thereof) -- tracking, alignment, calibration, and observation > III) Diffused light source, and its modelling, pre- and post-flight calibration, and goniometric calibrations > IV) Propulsion & motor control work > V) Nanosat solid models & Houman's thesis > VI) Computing/website > VII) Grant applications > VIII)AOB > > Talk to you all tomorrow, thanks! > justin
Attachments:
http://projectaltair.org/HyperNews/get/AUX/2015/11/02/17.58-64210-asseminternal.jpg
http://projectaltair.org/HyperNews/get/AUX/2015/11/02/17.58-182-assemexternal.jpg
http://projectaltair.org/HyperNews/get/AUX/2012/11/12/18.02-43361-Schedule-20120702_hqp.pdf
http://projectaltair.org/HyperNews/get/AUX/2015/10/04/14.03-62663-GPBoard.pdf
http://projectaltair.org/HyperNews/get/AUX/2015/08/18/08.29-60788-ionDeadlines_Fall2015.pdf
