2/19/13


Tuesday Feb. 5 Mr. Cullings

Very very light crew tonight. But that meant more of the food that Faith's mom made for everyone! I loved the dumplings!! Thanks Mrs. Chung.

The delay in parts has definitely slowed us down. Hopefully a lot of stuff will arrive today.

The climbing mechanism is definitely taking form and the action seems really smooth. I am looking at getting the flange nuts on the lead screw machined from aluminum for us.
Shooter team didn't really seem to make a lot of progress today because of the BaneBot motor leads breaking. We have three that now have to be fixed. So the shooter team began working on the usual bane of the Ursa Major existence- the bumpers. Sherri continued to CAD away and seems to be close to a choice on a final pneumatic cylinder that will be used to adjust the angle of the shooter. Programming team did what the programming team does best- developing difficult problems that had easy solutions. Cameras need power too guys!
Not much assembled on the chassis but alot of parts were cut. Faith finished assembling the guide wheels to help us climb the pyramid.

Alex Quinter and Mrs. Green worked for a while on the Chairman's Award and the Business plan. Thanks for showing up!

Mentors present: Bobby Nanan, Reggie Counts, and Jeff Meyers
Also thanks to JJ Pirtle for his help with the pyramid and the great stories about explosives!


Jan. 31, 2013
Posted by David DesPortes
Lots of progress in many different aspects of the robot building. The climber is really beginning to take shape. The drive team is experimenting with different wheels, trying to get more traction on the front wheels. The shooter team tried out the new wheels to spin the flying disks out of a chute without success. They could not get the disks to fly very far. May be a motor speed problem or may need to spin from above the disk rather than the side. The programming group was working on code for the cycling of the climber motion. The subsystems were unavailable for integration with the electronics and, therefore, the programming.
Many design details remain to be finalized. We still need a clamp for the upright pyramid pole to keep the robot from falling off backwards. We need a guide mechanism to help us get started up the corner of the pyramid. We need a guide to get the disks from the supply chute to the hopper. We need to locate sensors on the various parts of the robot to help with the overall control.

Jan. 22, 2013
Posted by David DesPortes
I am encouraging the team to conduct Failure Mode and Effects Analyses on each of the subsystems. A good general description of the process of conducting an FMEA is here:
http://asq.org/learn-about-quality/process-analysis-tools/overview/fmea.html
Just substitute "competition" wherever you see the word "customer".
Wikipedia also has a decent explanation:
http://en.wikipedia.org/wiki/Failure_mode_and_effects_analysis

The technique I would like us to use to identify the cause of a perceived problem is the fishbone or Ishikawa diagram:
http://asq.org/learn-about-quality/cause-analysis-tools/overview/fishbone.html

These techniques used now will help us avoid trouble after we have put the robot together.


Jan. 19, 2013
Posted by David DesPortes
See photos of prototypes here:
https://picasaweb.google.com/ddesportes/UrsaMajor2013?authkey=Gv1sRgCNi1jZ31q-XitgE
We have some good ideas that are proving out to be viable. We are in need of getting to final design quickly so that we can begin to build the real thing.


Jan. 14, 2013
Posted by David DesPortes
Want to give an update on the points I took away from the Mentor's Dinner tonight.
  • Two rule updates have been posted. We need to get and read these.
  • Non-round cross section pool noodles are permitted this year, e.g. hexagon or petal shaped.
  • Only motors approved in the rules will be allowed. Significantly the Fisher Price motors are not included this year.
  • The switch to turn off the robot must be available at the end of the match. So for us, this means at the height of the climb. The robot must be switched off before lowering it. We must also be able to connect the clips or ropes from the belaying system to lower the robot down. All this without climbing or using a ladder. We should have no trouble reaching the heights involved here but should consider where to place these items to make this reasonable for us and the event staff. We need to look into how we would get our robot down. We also need to be aware of how the belaying lines may damage the robot while lowering. The specifics of the belaying system are not evident, yet.
  • The 54" right cylinder is always assessed vertically, i.e. at right angles to the floor. Bumpers count against this limitation. This is a tighter constraint than I have previously considered. We need to check this closely. It will be assessed in the pre-match inspection.
  • Another concern for us is that we are not allowed to mar the disks. This affects us particularly in the shooter. We may need to look at a different wheel.
Other mentors that participated are welcome to add their thoughts and insights.

Jan. 14, 2013
Posted by Charlie Crews
Lots of good work was done tonight. The mechanism for loading frisbees was programmed and tested. With a preloaded tank, they were able to extend and retract the arm 17 times. I believe they were shooting for 14 times, so that's good. Faith presented the climbing mechanism again to make sure everyone was up to date on what was going on. Since I'm mostly involved with the programming group, my suggestions are skewed towards that, but I have a couple of thoughts. I'm trying to push towards starting the vision tracking, and it may be helpful as a team to decide how, or if, they want to use the camera to track the goals. Along those lines it seems like everything is far enough along that the team can start making decisions on how they want each part programmed. For instance, will one joystick button shoot all frisbees that are loaded? Or will it be pulled once per frisbee? Will there be any sensors to tell how many frisbees are loaded? How does the team want the climbing to be programmed (arms activated by individual buttons, one button combining multiple steps, any additional sensors)? Etc. etc. Most are minor details, but it will help the programming team to start making decisions on that now, and it probably wouldn't hurt to think about the best way to drive the robot in competition. Also, they need to install some sort of versioning software and have a system for backing up code. I've mentioned TortoiseSVN (free, and can be installed locally on a laptop), and there are also several free online alternatives if they would rather have that.
It sounds like they are trying to have a working prototype of a climber by Saturday. So I'm excited to see that in action.

Jan. 11, 2013
Posted by David DesPortes
Been rethinking the walking beam idea. Would like to incorporate a couple of ideas from other mentors. Rob suggested using the rung locks like are used on an extension ladder. See http://louisvilleladder.us.com/replacement-parts/extension-ladders-en/rung-locks.html. Eric A. suggests using screws for the extension mechanism. The combination of these two ideas is very appealing for several reasons. The rung locks are both forgiving and secure. The use of a threaded rod inside a threaded tube can provide significant distance of movement without any requirement to move away from the pyramid. There may be a way to use this to help us get started onto the pyramid rather than try to drive up onto it.

Jan. 9, 2013
I'm impressed with the Team's collaborative methods and teamwork. Don't lose that sense of urgency... there's not a lot of time!
This blog [http://mdfirst.org/blog/?p=553] is written by Anne Shade, a head inspector for Chesapeake FIRST and contains lots of good information and pointers.
Jeff

Jan. 9, 2013
Posted by David DesPortes
Light crew today. More work on the design of the walking beam. Resolved some issues with spacing around the corners of the horizontal bars. Started into more specific CAD work. Did not get the structural framework figured out. Decided to work on the CAD from the standpoint of the parts that touch the pyramid first and then create a structure around these parts. Electrical/Programming group got the bridge working, a very necessary step. Started an effort to mock up the pyramid in 1/4 scale using oak dowels. Keon and Sammy were working on this using the hand mitre saw I brought in. Will bring this back with me tomorrow. Intend to follow through and mock up the robot in 1/4 scale, too. Did not see what the shooter team accomplished today. Great food from Ameer's family tonight. Thanks!

Jan. 8, 2013
Posted 1/9/2013
by Mr. Cullings
Whew! For me it was a 13 1/2 hour day! It is so easy though when you work with such great students and mentors! Thanks to Bev and Jeff Meyers for the wonderful meal!
The drawings for the robot are pretty much drawn to full scale and the parts for the vital beam walker can now be CADD'ed. I am really impressed with this much more analytical approach that is being taken by the team. A Frisbee deployment system was mocked up and the team members had about 2 hours worth of fun throwing Frisbees down the hall at Rob O. Hopefully we can get some of the pictures and videos posted for you. The drive team was stymied by the lack of knowledge and the lack of parts for the timing belt-style drive.
I spent a great deal of time on Chief Delphi researching the belt drives and read a whitepaper comparing the pros and cons between chain and belt drives. I will post the white paper to the Robotics resources. I have my own concerns about the choice in drive but nonetheless I ordered some parts from AndyMark that will allow us to develop a belt-drive so that hopefully those fears can be assuaged.
http://www.chiefdelphi.com/forums/showthread.php?t=110724
Electronics team seems to have finished placing the electronics on the board but now need to begin wiring. Charlie and company also were finally able to update the Driver Station software.




Jan. 07, 2013
Posted by David DesPortes
The UltimAte Ascent is off to a great start in Team Ursa Major. The team has chosen a strategy which is to score in Auto mode in whatever method the shooter design permits, then in Teleop go to the feeder station and get four alliance colored discs, go to the pyramid and climb to the third level and then dump the disks into the pyramid goal. This should generate at least 56 points; a minimum of six in Auto, 30 for climbing to the third level and 20 for four disks in the 5-point pyramid goal.
Design concepts are well underway. The climber is expected to be a walking beam that will wrap around the corner post and climb up to the third level. The chassis will support the walking beam in an A-frame configuration. It will be four pneumatic wheels driven by two motors with a belt drive. The shooter will handle the disks in a horizontal orientation and use a spinning wheel to eject them towards the goals. This will reside above the A-frame. The electronics will sit on the outside of the A-frame.
Chassis designers are working on getting their plans into CAD. The shooter group is working on creating prototypes of two possible designs and have a solid concept for the hopper and feed from the hopper to the shooter. The climber group is mocking up the walking beam with cardboard cutouts.


Notes from Mentor meeting, Sept. 08, 2012:
Posted by David DesPortes

Confirmed that mentors can support the training session schedule proposed by the team. Will plan to provide make-up sessions on the Monday following the Saturday that has been planned. Mentors will generate an outline for their sessions and distribute to all other mentors for comment before presenting to the students.

The Sept. 29 training session will be held as a round robin for the Safety (by Mr. Cullings) and Intro to Programming (by Mr. Crews and Mr. Adler) sections. Then the Design section (by all Mentors) will be held for everyone.

Mr. Rosenberg will be teaching proper wiring and soldering techniques on Mondays until 4 PM.

Mr. Cullings will ask the school photography group to take on the project of videotaping of our training sessions for inclusion on the website and for future reference.

Joel Roth, the Hammond H.S. Psychologist will help with mentoring the animation efforts of the team.

Mr. Adler suggests checking out the FRCMastery website for ideas related to training.

The difficulty the team is facing in getting the LabView software installed and available to the students is related to the delays in getting new computers and/or new system images installed on the computers for the school year. This delay will be resolved by the end of the month. In the meantime, Mr. Adler will bring a laptop with the LabView software to the Sept. 29 training session.