Long time no post: Nov Competition, Review, Jan Improvement

So, last I posted in the VRC1414 blog Casey, Mitch, Bryan, Jonas, Justin, and Ben were all prepared for our first event in November.  As reported via facebook and twitter, our rookie team performed very well for the first time out at the Haverford Stampede on Nov 19.  We were the number two overall seed losing only one qualifying match, were event champs with 3057, and 169B as alliance partners, and also won the Build Award.  All six team members were very good in their roles the first time out for sure!  Below is a photo at the conclusion of the event together with our partners and the rest of the photos from the day can be seen here: http://www.flickr.com/photos/uprobotics/sets/72157628058398433/

Even though our performance exceeded expectations, we certainly were able to identify places we could improve.  So, during a nice break from meetings all the way through the new year we compiled our list for improvement via email, video review, etc to plan our next steps.  That list included:
1. Improve ground speed by swapping the 2.5" omni wheels for 4" omni wheels. We were defended pretty heavily once we proved to be a consistent scorer and feel the approximately 40% improvement in ground speed to go along with our agility could help up be more a proficient scorer in the future,
2. Tighter motor fastening by swapping out all motor screws for screws with thread locker. While we like a busy pit crew, we were tightening motor screws way too much at the Stampede.
3.  Exchange our eight "spliced" threaded beams in our drive modules for single 2.5" beams.  Dealing with the "extra parts" nearly cost us making match time once when we had to make a pre-match adjustment and this easy switch out is a no-brainer.
4.  Improve control over our arm and robot position in autonomous as well as adding selectable options for autonomous sub-routines through use of sensors.  Although we performed well in autonomous at the Stampede, we were entirely dependent upon human positioning of the robot and battery voltage - which led to a few misses we'd rather eliminate.

From that list we ordered some additional parts, took some needed time with family for the holidays, toured the team trophies around to everyone's house, the head coach did some sensor/programming learning, and we added three January meetings and one Feb meeting to our schedule to prepare for our next event on Feb 18.

So, thus far we've had two of our Jan meetings and Kwelaha 1.5 is coming along with improvements. 
1. All motor screws, threaded beams, and wheels are switched out.  This proved to be more tedious than we had planned as a few of the motor screws were really difficult to place (but we got em!) and the new wheels elevated our robot 3/4" and messed up our intake geometry - jamming barrels way too frequently.  So after several iterations and tests at and between meetings (thanks to Jake who will be joining VRC1414 in the spring for the extra help) we settled on moving our chassis cross members that serve as a hard stop for the accumulator one hole toward the rear of the robot to grab the barrels a little lower and just before today's meeting ended (thanks for the idea, Mitch!) we swapped out 2.5" threaded beams for 3" threaded beams that support the top of our polycarbonate sandwich to improve clearance. 
2. Sensors are mounted (4 bumper switches and one quad encoder) along with a new length of shaft we cut to accommodate the encoder.  Test programming for the bumper switches shows promise, the encoder still needs some work.  Stay tuned for next week's update on our autonomous improvements when we'll give detail to our plan.
3. We spent about an hour doing 2:00 at a time driver practice with varied drive teams today to get a good feel for our improved robot mechanically.  We're on our way to learning how to handle our changes and I'm excited by the quick progress after the long layoff in addition to having a faster machine. 

Photos from our Jan meetings (thus far) are here:
http://www.flickr.com/photos/uprobotics/sets/72157628904216381/
Looking forward to our two remaining meetings and the Feb event!

Final preparations ... Nov 2 and 7 meetings

We're in the last stages of getting ready for our first event, which means we spent the last two meetings tuning in autonomous routines, driver practice, and getting all of our documentation and display items together for our Nov 19 event.

Three items of note during these meetings:
1. We completely replaced our intake foam and rubber bands.  They were still performing, but were degrading, and we want to ensure no intake issues.
2. 11 is not equal to 10 ... OOPS!!! Somehow we missed that the max number of motors allowed on the robot was 10 - we had 11.  Fortunately we have plenty "under the hood" on our lift joint (see our critical design testing/iterations (and video) in this post: http://robobraves.blogspot.com/2011/08/iterating-optimizing-dog-days-aug-9-12.html . All we needed to do was remove one motor from the lift (reducing from 4 to 3).  The three motor lift with latex tubing spring assist is still plenty of oomph - all we needed after motor removal was a slight bit of autonomous routine testing.
3.  We shot video of our autonomous routines.  While we'd like to add sensor to improve reliability, we've run out of time for that right now and we're pretty good at managing beginning battery voltage and robot placement, Here's a quick look at our four routines:
http://www.youtube.com/uprobotics#p/u/2/MrAwPYNtpX0

Generally, we're pretty excited about things with only one more meeting - on 11/18, which will be used as a team celebration and pack up - before the event on the 19th.  See you on the field!!!

Autonomous Menu "complete" ... late October meetings

Only a few weeks until we compete for the first time ever.  We've spent almost all of our time lately on minor mechanical tweaks, a little bit of driver practice and really hammering away at our autonomous routines.  There are four of them - one to score in the isolation zone, another to score in the interaction zone, a third to scatter the stack, and a fourth just to sit still.  Special thanks to the KTOR crew for showing us a template we could use for routine selection using jumpers. 

After reading the vex forums (www.vexforum.com) we decided that using the jumper method would be best suited for our rookie endeavor.  While the routines aren't perfect, they all are highly functional, pretty much just using "wait" statements and paying close attention to starting battery voltage.  If time allows we may try to add some simple switches/sensors so we're less dependent upon voltage and wait time, but we feel pretty good about what we have as is. Here are a few photos of the mechanical setup that supports our routine selection:

Autonomy ... and settling into roles ... Oct 12 Meeting

Flurry of activity at our one-hour meeting today:
1. Bryan & Jonas concentrated on autonomous programming today, got one routine done, got a huge chunk of another one in the bag and tested as well.  Running an autonomous routine for the very first time and seeing it succeed was the highlight of the day for everyone for sure! Shout our to the KTOR crew for helping us with programming templates for EasyC.  That little help is going a long way, thanks! Bryan also brought a draft of our scouting form for review to the meeting.
2. Ben & Justin concentrated on a short mechanical tune up, then developed the start of a checklist for between match check ups to help ensure full functionality in all matches.  They then supported our driver practice.
3. Casey & Mitchell mounted, secured and labeled out pwm/jumper autonomous selector hardware and then spent the bulk of the time on interaction zone driver practice.  They are getting there!

We're certainly really coming together as a fully functioning team at the right time.  With a handful of meetings still to go before our Nov event, the anticipation is surely growing.

See you next week,
Kressly

Tuning Up/Getting Ready/Event Planning_ Sept 28 & Oct 6 meetings

One hour weekly meetings are flying by, but are productive. To those who have sent all the positive feedback, thanks!  As promised, but a little late, robot specs:
Drivetrain - 5 motor eight omni wheel drive.  4 motors driving 4 of six forward facing wheels with tank style control and one motor driving two middle sideways wheels controlled by joystick buttons.
Arm - 4 motor surgical tubing lift assist arm with a 60:12 (5:1) single-stage high strength gear reduction.  Y cables allow two channels to power all four motors.  Enough torque, rather quick, and shared load across motors with the surgical tubing help make it easy to operate smoothly.  Hard stops prevent arm from extending CoG to robot tipping point.
Accumulator - 3 object capacity, 2 motor powered tank tread covered with VEX foam intake.  Foam held in place by adhesive backing and woven #32 rubber bands.  Polycarbonate "sandwiches" objects securely and allows for flexible hold on different sized objects.  "Soft stop" keeps objects from falling out the accumulator top.

Accomplishments during these two meetings:
We've gotten in a little driver practice - mostly in the isolation zone, decided as a team to specialize jobs at the Nov event, divided up jobs, started developing a scouting information sheet, talked over tournament structure, and have an autonomous programming template built from a sample that will allow us to program our four desired autonomous programs.  The team is handling things in a very upbeat and professional manner and we're excited to watch things come into place.

Our goal between now and the Nov 19th event is simple - be as prepared as humanly possible in order to maximize the chances of success.

autonomous planning / promo shoot: Sept 19 meeting

Good to have the entire team at Monday's meeting.  We planned and prioritized our autonomous strategies (programming to begin next week), got some driver practice in, and shot a bunch of video and stills so we could put a 2011 promo video together.  Here it is:

Full robot specs are more to come next week!

-Kressly

Meet Kwelaha: Sept 14 Meeting

After a short hiatus to concentrate on the start of the school year, the Robobraves got back to work on 9/14 finishing off the punchlist items, tidying things up, and declaring Kwelaha (which is "Hope" in Lenape) mechanically complete.  After initial testing before the short hiatus, the decision was made to remove a stabilizing/connecting bar (this piece) from the underside of the accumulator.  This will allow for our bottom polycarbonate sheet edge to flex more freely, allowing for both balls and barrels to be collected in multiple orientations with equal proficiency.  Other than that one minor tweak, the design as previously discussed here looks to be very solid and we're thrilled at the results of our initial testing with a "complete" robot. Here's a short set of video clips from our testing:

From here we will be concentrating on autonomous strategy and programming, driver practice, and competition readiness.  The team is pretty excited to see it coming together and so am I.

Until next week,
Kressly