Home of MagAO and MagAO-X.
Look what the wind blew in. We met some new LCO denizens this morning. When Laird left his room for breakfast he was surprised to find a horse standing just outside his door.
By the way this post is especially for horse lovers Emmeline and Annabel Close, who I hear are following along at home and requested some more animals.
The PI got hit with a rock this morning. That’s how hard the wind was blowing. He’s o.k., and the wind has died down tonight.
I’ll let Marco update us on progress with fixing the TSS. For now here are a couple of pictures of the work being done there:
Laird and I finalized the alignment of the W unit tonight. It looks like none of the components shifted during shipping so we don’t have to re-align anything on the board – a big relief. We also took a set of readout noise measurements, with decent results. Things are as good or better than they were at Arcetri. For the AO-nerds out there, the CCD 39 (our WFS camera) is turning in around 9 electrons RON at 1 kHz frame rate, and roughly 4.2 to 4.4 electrons on our slow (~100 fps) mode. We had both cameras running and were modulating during these measurements, so we fell pretty good about them.
A few pictures of the WFS in the NAS:
Some good quotes from the last 2 days:
“It’s pretty hard to keep VisAO down for more than an afternoon.” (Jared Males, spectacularly wrong)
“No! I want this to be a bonding ritual between us – and you know we’re going to do this every time we come up here.” (Laird Close, after Jared whinged about taking the same measurement for the 427th time in the last year).
“My attiude is when something is unknown, take the conservative choice, so fix it.” (Armando Riccardi, the ASM man)
Man, the ASM seemed to work really well and the AO group continue testing the system all the day BUT at a certain point the system started whistling!!! All the actuators were disabled, the system powered off and the shell was safe against the reference body but it was still whistling at about 2 Khz!!!!
Microgate people found the problem on the TSS (Thin shell Safety System): a single crate, after a while, was not applying constantly the wind safety current and caused the shell oscillation
That crate was oscillating with few [nm] RMS movements:
On the Unpacking day 10 Microgate people will address the problem.
Sadly, Microgate people were forced to delay their flights…
…but we are happy to work again with them!
The big story at LCO right now is the wind. It is strong enough that it’s hard to walk in a straight line. Here’s a plot of the last 24 hours:
It’s still nice and calm in the cleanroom though, and we’re getting lots done. ASM testing continues apace.
We finally mounted the W-Unit on the NAS today. Our wavefront sensor (WFS) is called the W-Unit because the light path makes a W. It is the instrument which actually measures atmospheric turbulence, and it also contains our visible wavelength camera, VisAO.
After a skype consultation with the W-Unit Master (Enrico Pinna), and with some help from Armando, we hoisted the board onto the X-Y-Z stage and bolted it down.
The boys from Microgate (Mario and Frederico) replaced a power supply in our “minicrate”, which provides high voltage power to our piezo-tip-tilt mirror and camera lens. We had developed a problem where those two components seemed to cross-talk, making a worrisome chatter under certain conditions. It’s fixed. Thanks guys.
The side attraction for the last 24 hours has been the VisAO computer. This computer operates the VisAO camera – it saves the data from the CCD and controls focusing and filter selection. Shortly after mounting the VisAO box (containing the computer) on the NAS, the motherboard failed, specifically the hard drive controller. It is a matter of some debate what caused this – it’s been shipped from Tucson to Florence to Las Campanas, and taken apart and put back together many many times over the last 2 years, but mounting could also have stressed the box enough to damage the board inside.
I knew this was going to happen, because motherboards suck. I even carried a spare with me in my luggage because I knew this was going to happen. The brand new spare didn’t boot. Disaster. On a project of this size you might think of a $200 motherboard as a nothin’ part. But as a great man once said “It’s nothing ’til you don’t got one. Then it appears to be everything.”
After trying everything else we could think of, we hacked together a solution out of a retired server and the PCI guts of VisAO. She’s limping along. The server used to be called “Vizcacha“, so I think VisAO now has a mascot.
We have now turned everything on that we can think of and the only casualty is the motherboard. All of our motors spin or step, our mirror modulates, and our cameras take good data. We’ll do a bunch of rigorous checks over the next few days, but the initial indications are great.
Yes we did! The last night the shell was re-clocked by Armando and Richard that imposed their hands so this morning the shell went again inside the clean tent and was installed by the AO team. The installation procedure took a bit but the TS1 successfully went up and was pulled by the bias magnets against the Reference Body in the standard safe position. After a relaxant trip to Magellan telescope with Laird and Tyson as Chair, Armando fixed the central membrane in the working position and the ASM was ready for slewing tests. No big issues so the system seems really to be on the road to go to the telescope!
Here’s a video of the last part of today’s shell mounting. Skip ahead to about 11:30 for the big moment.