MR. SCHUETZE'S WEEKLY UPDATE
Another long week:
Weight!!!
A very lively discussion ensued this morning at the called meeting for all team
members and mentors present. Some mass measurements where made afterwards and we
are moving forward with a few items. The plywood sides to the ball cascade each
weigh over 3 lbs. The same size aluminum sheets each weigh 2 lbs. We are going
to stencil in our team name and number into those pieces which will be on the
side and cut out the letters. If we put a mylar backing which has been painted a
high contrast color that will satisfy a rule requirement of having our team name
and number on the robot. The lexan side panels for the same device also each
weigh 4 lbs. We are going to remove at least 1/4 of each panel in the unused
void beneath the bottom rails. Working from memory, the steel sprockets on the
wheels each weigh 1 pound and my calculations from the AndyMark cad file using
2.7 g/cm^3 for Al - I generously estimate that each new sprocket will weigh 0.3
lbs. That works out to likely be a 3 lb reduction in mass. We are also going to
replace the steel shaft on the wheels with Aluminum shaft. The wheels are driven
and not the shaft so that should not be an issue unless we add a hydraulic lift
system and start entering the robot in some low-rider shows and bounce or hop
the robot:) We may look at replacing either one or both pieces of lexan on the
ball cascade as a last resort with wire window screen since the lexan is not
providing much structural support at this point. I did get frowns all the way
around on that suggestion. The aluminum for the ball cascade
came in at 11 lbs
and the lexan at 8 for a combined mass of 19 lbs.
We did make one final mass measurement this afternoon. We put the whole robot,
electrical board, pieces of the ball cascade, a mini-bike cim motor (will be the
motor for the ball cannon), the Con-Vader fabric and the robot comes in at 9 lbs
under weight. Still to add will be some #25 roller chain for the sweeper bars
and the entire structure for the ball cannon.
Here I go again, Next week is now the most critical week of the build. We have
13 days until the robot ships and 12 until we crate the robot. Tasks for the
programming team are now getting the camera system to find the goal and orient
the robot for a shot and to script out our autonomous commands.
Mechanical team targets -
1) Mount the fabric for the Con-Vader. It was cut to width today and contact
cement was tested and almost held. Next test is to sew velcro onto the belt and
test. I am fairly certain that velcro will hold.
2) Chain up the ball sweepers for a test.
3) Replace the wheel axles with longer shaft and of Aluminum. We need longer
shafts with the collar locks on the outside to pin the entire bottom assembly
together.
4)Complete the design and mount the ball cascade
5) The electronics board has found a home on the side of the ball Con-Vader. The
components placements were worked out and being installed this weekend. A very
sturdy lexan cage needs to be built to protect them from errant poof balls and
possible falls off the ramp.
6) A shelf is being built to mount the ball cascade and the ball cannon.
7) BALL CANNON
We are now working on the Autonomous mode. We first want to shoot 10 balls. 1.Pre-match setup. A.Face robot forward toward the goal. B.Load 10 balls. 2.Execute. A.move right x sec. B.move forward x sec. C.find target. D. Fire. thats what we want. Timing (# msec), Speed(% max), Direction (4 directions). Set PWM simpifys maintaining the code which motors we are connecting to.
-Jack
Today we got the robot driven! The code worked. We
just made some minor change with reversing the direction so it wasn't backwards
anymore. We also changed the deadband numbers so the rotation wasn't so fast.
Now we're getting the autonomus fixed up.
-Exempt
Wooooo today we actually drove the robot. We got all
our code for which directions it would turn and we put in the code for it to
rotate. After all the excitement of seeing the robot drive we came up to work on
our code for the autonomous mode.
-Phoenix
Well because i forgot to post on monday i'm doing it
right now. Well on monday we worked some more on the code for the autonomous
mode. Right now what we have is a state machine. The different states we have
now are wait, move, find, and fire. Yesterday we added a few more things to the
code.
-Phoenix
OK, today we worked some more on the autonomous code.
We have the WAIT down. 
and now we have the RIGHT direction. Lauren and my task is to fix up the code
including the gyro for later use to tell us what angle the robot is in and where
we want to be. We're hoping to later go at an angle to the goal instead of RIGHT
then FORWARD.
-EXempt
Gyro Stuff:
Our gyro returns the number of milliradians that it has turned. So, our task is
to be able to calculate the number of miliradians we need to turn to rotote X
number of degrees. For example:
ROTATE, 45, CLOCKWISE
ROTATE, 90, COUNTER
The formula for degrees to radian is:
theta * (PI/180)
where theta is the angle.
So, given this how many millradians do we need to turn to be able accomplish the
above robot commands?
Sat Feb 04, 2006 12:43 pm
me and lucian
mounted 8 igus pillow block bearings for the four 3/4 inch pvc pipe for belt
....also lucian made some very cool support braces for the con-vader? yea.... At
this point the robot looks so ------ sexy! lucian is going to post up some pics
later.
-Gilbert
Posted on: 02-04-2006
Well today I
edited the audio files (interviews) Alex and I had done last Saturday. I also
took pictures of the robot when it was moving. Plus I added some content on to
the interview page. I was trying to figure out how to put the audio files on to
the page but couldn't. I'm probably going to keep on trying next time. Yeah well
that's what I did today.
-Evelyn