Tuesday, February 20, 2007

Our nameless robot has been shipped!!!

Around 5:00 today, as we were wrapping plastic around the outside of our awesome crate, FedEx arrived to collect our robot! Enjoy your day off tomorrow, and get excited for packing stuff for portland on Thursday...

THINGS WE HAVE TO PACK FOR PORTLAND (in addition to tools, etc.)

-the radio for the robot that we accidentally forgot to pack into the crate after taking it off the
-chain tensioning delrin rod system
-grip tape
-emergency ramp kit: rivets, punch (for holes in surgical tubing), surgical tubing (about 3/8" outer diameter, 1/8" ID), box cutters, drill bit (in rivets bag), back-up plates (washers for pop rivets), cable and crimps...
-slides for bottom or ramp supports
-extra signs with school name, sponser, etc. (already printed)
-and more...think about what we need!

other:
-strategy
-figure out what to do about indicator light for which we're missing the relay...

good night--go catch up on all that lost sleep!

Monday, February 19, 2007

We're 121 lbs!!!...

...with a 12V battery.

After a moment of freaking out about needing to lose 11 lbs, we realized we hadn't removed the battery. The arm wasn't on the robot, however, so as far as we can tell, we're right at 110 lbs. At least we don't have to go through the extreme weight loss program as last year!

Oh yeah, did I mention we have sweet ramps that get released by a nifty flipper?! Ok, so maybe I shouldn't be so excited given we're shipping in less than 48 hrs, but I have to say I feel a lot less stressed than last year or the year before. We also have a gripper that's done, save maybe a few simple improvements tomorrow as we test.

I took some detail photos of the robot tonight, so if any of you readers want to build a copy of our robot...the pictures say it all, so I'll end my post with short list of things we might consider doing before we ship (should we have the time, that is, in some cases):

-color code for different allen key sizes
-spray paint 1700 on bumpers
-signage (sponsers,
-cart (at least get dimensions so we can do after ship, if it comes to that)
-stuff i can't remember because it's too late and my memory is going...

other:
-strategy

Sunday, February 18, 2007

2 days left (plus a little...)

ACK!

And (surprise surprise) weight is an issue, though not as bad as last year. We're at about 107 lb without the ramp release mechanism or dampers or a few smaller things. Hmmm...

Ramps are almost done, meaning they're dampened, hinged, and supported; they just need some stronger springs. We made do with bungee cords tonight (to open up the secondary ramp), and it was pretty sweet. We did note the problem of getting the cable (connected to the ramp frame and the ramp support) caught around the ramp support...

A gripper idea in the works (suction-y), and we have a working design already.

To do:
ramp release mechanism
wheels/slides/whatever for end of ramp
finish putting grip tape on second ramp
cross-bracing for tower
(test ramps with paly?)
drill last mounting holes for bumpers

See pictures ;)

Thursday, February 15, 2007

We're getting there

Somehow Jim and being at IDEO make everything work out. We're now done with the secondary ramps and have mounted a main ramp on hinges connected to the chassis (and removed it, so electronics could flip the chassis and drill a couple holes). Our next plan for action is to figure out how to mount the vertical ramp supports and the dampers on the ramps. I think we're sticking to the cable idea for aligning the supports. We also have somewhat of an idea to mount the dampers (we did all of this on our prototype!), but this needs some reworking because the top back chassis rail isn't one piece straight acros the width of the frame. Rather, there's a gap in the middle, leaving no room to mount a damper.

The gap is, however, a perfect fit (as it was intended to be) for the new gripper design that is similar to our previous design, except it has two prongs spaced >10" (the diameter of the spider arm circular plate). We need to finalize this tomorrow and fabricate it, too...and test it on THE RACK! Once this design is set, we also need to add cross bracing to the tower at heights that're appropriate for mounting touch sensors (to prevent the arm from rotating too much in either direction).

The battery mount is also in progress and will hopefully be done by the end of tomorrow.

On top of all the stuff already listed above, PLEASE READ THE LAST FEW BLOGS FOR OTHER THINGS THAT STILL NEED TO BE DONE.

[OI board? (currently we're using last year's--is this even legal?)
bumpers, signage, flag holder, etc.
crate! contact mr. reichling... (Kersten?)]

Little stuff that I don't want to be doing the night before/the day of ship...


A big thanks to Jim for staying with Chrissy and me these past few days until AFTER 10:00!!

Tuesday, February 13, 2007

Ramps (cont.)

We're almost done with mounting the surfaces on one whole ramp (the main ramp is done, and we need to mount one more aluminum sheet, which has already been punched out, on the secondary ramp). Once that is done, we can work out how to mount the two pieces together, incorporate the support, and mount it all onto the chassis.

Along with the list of stuff in my previous blog, these things also have to get done:

Ramp release mechanism--I think we're at a point where we should be able to have it all ready to mount on the tower of power. Let's try to get that done within the next two days.

Gripper redesign--it turns out the design we've been planning to use doesn't work. Chrissy and I stayed really late trying to work something out, but this needs more thought.


We're going to IDEO tomorrow and getting there AT FIVE-THIRTY (5:30!!!! NO LATER PLEASE!!!). Maybe you've noticed we've been getting there a half hour late every time, which is bad because we HAVE TONS TO DO (and we're wasting Jim's time if we're not there)!!!


When we go, we need to take:

-The chassis and arm (if programming is ok with this...if not, maybe they can follow)
-A battery (so we can weld a mount onto the chassis)
-Notebooks
-That bag with safety glasses and that 1.5' piece of pvc
-and probably other stuff, too...

Ramping it up...

oh dang. i just lost my post because my internet hung. here's a quick version of it.

main ramps = DONE!
secondary ramps = started! aluminum sheet surface cut to correct size and shape.

to do tomorrow (sounds like lots to easy stuff-but will take time!!! only a week left!!):

-draw grid on ramp material and mark points with the punch (borrowed from ideo. don't lose it)
-arm: determine desired length and angle of gripper
-bumpers
-signage--read the rules
-pvc flag holder
-joystick board--place to put joysticks, oi...
-think about hinges/dampers for ramps

other stuff:
-crate? kersten, are you in touch with mr. reichling? HOW IS THE ROBOT GETTING SECURED INSIDE?
-electronics cover
-battery mount (orientation? placement?)
-cross bracing on tower of power

other other:
-chairman's?

Sunday, February 11, 2007

Sunday, Jan 7

A lot of punching went on today.
First, we all arrived at Castilleja and worked on some stuff (like moving tables, sending emails, and making bumpers) and then Monta Vista arrived to use the rack and then Allie and Anne worked on the crate and Jimmy woke up so we went to IDEO, but not before Bud dropped by and we all had a chat, which was great because Bud is awesome. And then he came to IDEO with us and stuck around for a while, and then programming came to IDEO, so there was a big programming/electronics and ramp design party in the shop, and we punched a lot of stuff and the upshot of all of that is that we have a main ramp that holds more than we need it to and that weighs 7.4 lbs! YES!
Weight check:
-4 ramp frames = 15 lbs
-chassis and arm and tower = 65 lbs
-electronics board = really light because thy remounted stuff on a sort of corrugated plastic sheet.
Also, we need an optical potentiometer.
Also also we need to put together (that is, clamp, drill, rivet, punch) the rest of the ramps, and then we need to support them, and then do hinges, and then dampers. So keep cracking, guys! Keep up the good work for the next 9 days (AAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!!!)

Tuesday, February 06, 2007

monday

Today we wrote letters for a while (which are due TODAY, btw) and then, once we figured out our transportation, headed over to IDEO. Jim has machined us some wonderful stuff, like transmission mounts and the motor mount for Chrissy's arm. We also had him drill holes in the new chassis and we can put wheels and (almost) transmissions on the actual robot. We still don't know what ramp material we're going to use. We still (consequently) don't know whether we'll use a flipper (Free Willy) or some latch and cable device to keep the ramps in (does anyone else think that latches and cables might be a bit iffy if we get run into?). We still might end up buying the Andymark transmissions. We need to go to Alan Steel to buy some stuff (there's a list somewhere... Julia?). If anyone knows anything about where to buy structural bamboo, post a comment here or talk to me or Julia or Chrissy about it.
Thanks to Ms Doerr for the sushi.
Good work on the crate, freshman.

Saturday, February 03, 2007

Saturday

Today we:
-worked on the crate with our wonderful parent volunteer, Mr Reichling. It's now at the painting stage, and we should be finished very soon (which is good, because the robot needs to ship very soon).
-worked on the whole ramp system
-sent Kersten to Ace and IDEO for hinges, allen keys, and advice
-skyped emily
-ate lunch
-drank tea
-made a mess/ work in progress
-cleaned it up
-tested the now complete (if somewhat flawed in the hinge and damper category) ramp system to see that it (mostly) WORKS! So that was cool. It looks like all our effort to design it has worked out.

So now we need to:
-see what sort of surface we want on these ramps
-see if we want to change the ramp release mechanism (cable and latches?)
-go to allen steel for possible ramp material and the aluminum axle rod for the arm
-figure out what we're going to do about our transmissions. The options are to buy the Andy mark ones, use last years' (which may not be legal, so we need to see what the rule book says about that), see what the authorities are going to do about the ones from this year, or ask Jim if maybe he can help us modify them
-go to IDEO monday at 5:30 to talk stuff over with Jim
-WRITE OUR LETTERS
-build the robot and win regionals and nationals

so get to work, everybody! (and if that isn't motivation enough, talk to Julia and see what phrase she uses)

Mostly ramps

The coil springs definitely seem to be working at the joint b/w main and secondary on our 80-20 ramp! (note: depending on the final surface material for our ramp, mounting them may be a little more challenging, but doable, of course).

The dampers are also showing promise; we used some L-brackets to mount them onto our 80-20 chassis and ramp and slowed down the 20 lb ramp significantly (not necessarily enough, but the real ramp won't be 20 lb...). Unfortunately, even with a less significant crash into the floor, the end piece on one of the dampers (with a ball and socket joint) broke. It's still usuable, but this is a problem we have to address.

The mesh seems to be strong enough to hold a robot, provided there is no hole cut out for the ramp release mechanism. If we go with the mesh (possibly two layers of it?), we'll have to:
1) rework the release mechanism (not completely, but I don't think what we currently have will work since it requires a hole...)
2) consider the sag-factor: will the robot stay above 12"? will sag prevent robots from being able to climb up the secondary ramp and onto the main part of the ramp?


To Do:
•Sat Morning--PLACE A MCMASTER ORDER SO IT'LL ARRIVE MONDAY
•plot out location of transmissions and electronics board (keeping in mind the arm has to fit "inside the chassis" at the beginning of each round, before it flips "open" to be in front of the robot)
•consider whether our arm/gripper is going to work with/fit over the black flexible-ish tube on the spider arms
•calc exact distance on either side of robot in home zone when ramps are deployed, and possibly get a max secondary ramp length based on this number
•continue work on ramps: SUPPORTS (either buy hinges from mcmaster or pick some up from ACE; make supports from wood?; cable...possibly buy for crimps for when we need them eventually)
•buy more transmission sprockets if we decided to run two loops of chain from each transmission (one to the middle wheel, and one to the back wheel). (but we don't need any more chain! just possibly some master and half links)
•SKYPE EM AT THREE!
•Mr. Reichling will be here to help construct crate! maybe paint it, too....

see ya! (and don't forget your HOMEWORK :D )

Friday, February 02, 2007

JIm is a welding master

Duh. Ok, we all knew that. Still, he continues to amaze me! Tonight he welded the main platform for one of the ramps. In addition, he welded the two sides of our tower of power, complete with homemade L-brackets that will allow us to adjust the placement of the tower on our chassis. Our real robot is still looking pretty skeleton-like, but it's beginning to take form!!!

In other news, we got our 72 tooth sprocket today. Some funky stuff going on with a couple of teeth, but according to Jim, "the chain doesn't care," so we're ready to proceed on that front. Some folks also worked on prototyping with wire mesh on the ramp. Jim has also suggested a thin sheet of aluminum (for Kersten, preferably one that makes cool sounds).

To buy (this is also in my notebook, which isn't with me, so I may be forgetting something):

ALUMINUM ROD (to replace the steel one we're currently using for arm)-3/4" diameter, I have a part number (mcmaster)

Hinges for Ramp--Kersten and I started working on this, considering what kind we want at each joint on the ramps ("leaves lay flat" hinges, etc.)

Two 1/2" shaft collars (I think we may have some of these, so let's check first)

To find out:
-Do our current coil springs on ramp work without a pin in the spring hinges at that joint (in other words, would the coil springs with springless hinges provide sufficient ramp-unfolding action)?
-What's our status on weight? (the main platform of a ramp that Jim welded for us is 3.8 lb, so we're already at a total of about 40 lb for the welded frames of both ramps, the tower of power w/o the arm, and the chassis frame).


Lastly, DO YOUR ROBOTICS HOMEWORK!!!! IT'S *REALLY* IMPORTANT. We need a letter from EVERY one of you!

Here is the link to the specifics of the assignment, again, just in case:

http://www.usfirst.org/community/frc/content.aspx?id=4066

thanks!