Here are minutes of our telecon Thursday June 23, apologies for the delay! -- please just reply with (or let me know) any corrections -- thanks! And looking forward to talking with those of you who can make it at the Skype-telecon today in an hour from now:
Attendees: Just Arnold (NRC) and me this time.
First, the present situation here in New Hampshire: Yorke and I have decided that I should work on setting up a launch and recovery site back in Victoria, to complement James Forbes's site in Montreal, as Yorke is currently right in the midst of constructing a new house here in New Hampshire, and he is also currently completely committed with other (fortunately related, but separate from ALTAIR) Dartmouth work, and thus he very justifiably feels he needs to take a break from ALTAIR launches and recoveries. In support of this, Yorke has extremely kindly given me instructions on the myriad parts of ALTAIR that he designed and constructed himself, including, as just a few examples, the telemetry, the cutdown system, the gondola skeleton and foam superstructure, etc etc, so that I'll do my very best to reproduce them in Victoria. I will be here in New Hampshire as planned until the 27th of this month, and will be sending some of the necessary UVic-owned equipment (as well as doing work on software, on simulation, and on the propelled dummy payload, with more on those below) back to Victoria during this time, in order to further that goal.
The motorized, propelled version of a dummy payload for flight tests via drops from a tethered balloon is now assembled and functioning! -- a video can be found at
https://particle.phys.uvic.ca/~jalbert/MotorAndPropTests/MotorizedDummyPayload_6jul16.MOV
and some photos of the assembly are attached in the links at the bottom of this message. The propulsion and axle rotation are functioning, however I still do need to make the parachute/parafoil cutdown system for it (per Yorke's ALTAIR cutdown and parafoil steering system design), which I will do back in Victoria.
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) as well as the white "Avian-B" Lambertian reflective paint for its interior -- is currently back in the machine shop at UVic for machining and painting. This will be a field photometry check device to, in the field immediately before launch, and right after recovery, cross-check photometry information from the ALTAIR gondola (to an accuracy and precision of about 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.) Some renderings (of the upcoming device) are also attached in the attachment links at the bottom of the message. UVic machinists say that they will have it ready in approximately a month or two.
We also now have the hardware for (a completely separate) survey-tripod-mounted device to cross-check yaw-pitch-roll information from the gondola (e.g., on days before/after flights) -- a photo of this hardware is in a link at the bottom. That hardware 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) and two adjustable angle mounts (http://www.thorlabs.com/thorproduct.cfm?partnumber=AP180). We'll make the fittings to attach the adjustable angle mounts to the tripod, and to the payload, back in Victoria.
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.
Back at UVic, Karun is working with a sample microcontroller board (with Microchip PIC18F87J50 microcontroller) from the UVic electronics shop, 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 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
and now the setup is all together, and just waiting for monitoring sensors (motor RPM, current, temperature) and microcontroller control:
https://particle.phys.uvic.ca/~jalbert/MotorAndPropTests/IMG_2198.MOV
As a backup / cross-check, we are simultaneously trying an Arduino-based control system (which uses an Atmel ATMega 2560 microcontroller). 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. Separate propulsion battery will of course be carried.) A screenshot of a propulsion system slow-control and monitoring program which I've been working on is attached.
Regarding simulation of the above, James Hartwick (senior undergrad here at UVic, who has done an enormous amount for ALTAIR, including much of the current projectaltair.org website, light source work, etc) has now written an ALTAIR flight propulsion control and simulation program, which includes GFS (global forecast system) file input, for both forecast and real-time information of winds at all points in Earth's atmosphere. We'll have plots, images, and data from his software coming up very soon. I am developing a visualization interface for this control and simulation program, which will be based on Google Earth, but display the real-time (as well as forecasted) winds within Google Earth in a way that is somewhat similar to this site:
https://earth.nullschool.net
I'm working on a streak-vector display of winds within Google Earth that is reminiscent of the above site, and you can see a first attempt (with a single streak) here:
https://particle.phys.uvic.ca/~jalbert/GoogleEarthWindMovie.mov
and an attempt with multiple streaks here:
https://particle.phys.uvic.ca/~jalbert/GoogleEarthMultiStreakWindMovie.mov
Google Earth, while wonderful, is not open source, and does not presently have a programming interface (it can only be scripted with .kml files, which cannot, for example, loop over multiple lines of code in the way a programming interface could). I am thus working on versions of the above using NASA World Wind, which is an open source and programmable Google Earth alternative.
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 *today* (July 7), at the new 6 pm Eastern time (an hour from now).
cheers, thanks very much all! justin
On Thu, 23 Jun 2016 20:03:37 GMT, Justin Albert wrote:
> Hi all! > > Telecon today (June 23 in North America, June 24 if east of the prime > meridian & west of the international date line) trying the *new* time > two hours from now: 6:00 pm Eastern North America (3:00 pm Pacific, noon > Hawaii, midnight central Europe, and 8 am Eastern Australia). Discussion > items include: Meade telescope status and tests; flight planning; 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) Telescope tests and current status > II) Flight planning > 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 in two hours, thanks all!!! > justin
Attachments:
http://projectaltair.org/HyperNews/get/AUX/2016/07/07/13.52-96622-dDummyPayload1_6jul16.jpg
http://projectaltair.org/HyperNews/get/AUX/2016/07/07/13.52-91301-dDummyPayload3_6jul16.jpg
http://projectaltair.org/HyperNews/get/AUX/2016/07/07/13.52-22712-dDummyPayload5_6jul16.jpg
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/2016/05/22/18.23-93827-tch-roll_calibTripod2.jpg
http://projectaltair.org/HyperNews/get/AUX/2016/06/08/18.04-17780-asseminternal3jun16.jpg
http://projectaltair.org/HyperNews/get/AUX/2016/06/08/18.04-71442-assemexternal3jun16.jpg
http://projectaltair.org/HyperNews/get/AUX/2016/05/04/17.45-92797-opulsionMonitoringNew.jpg
