Posts Tagged ‘ frcbuild

Day 4: Field Construction, Whole Team Meeting

Field Construction

The field construction team made huge progress today.  A large group of students worked hard all day to complete both the minibot pole and one grid of scoring pegs.

Team members assemble the scoring pegs.

Team members assemble the minibot pole.

The completed scoring grid.

Whole-Team Meeting

We had a whole-team meeting at the lab today.  We discussed the progress thus far in the season and decided on distinct mechanism groups that will work on prototyping and designing each mechanism.  The slides are shown below.

Mechanism #0: Drivebase
Mechanism #1: Elevator/Arm to lift tubes to scoring height
Mechanism #2: Tube Grabber
Mechanism #3: Minibot

Design

The design team did not work very much today.  After the whole team meeting and the field was completed, we met to discuss the benefits of elevators and arms for mechanism 1.  Although no decision was made, the group seems to be leaning towards elevators for several reasons.

  • We are very familiar with elevator design.
  • Elevators can be extremely fast
  • Precise height positioning is easier with elevators.

Here is a video of our 2007 robot and its clone, team 968, and their elevators.  Although our grabbers for this year may very drastically from their grabbers, the video gives a sense for how fast these elevators can move.  The elevators are able to easily move to any position in less than a second where most arms would take more time to raise a game piece.

FRC Season Day #1

Today was an extremely productive day at the lab.  We built a significant part of the field, tested the game elements, began design, started manufacturing and continued to work on programming.

Field Construction

As soon as we got to the lab, a large group of team members got started building a replica of the most essential field elements – a rack and a tower.  We intend to build enough of a low-cost field for testing and the NASA Robotics Alliance Project will purchase a complete field for the west coast in the coming weeks.  The field will stay at our lab during the build season but will travel around the state for various off-season competitions afterwards.

Several team members cut parts for the field.

The structure to hold the rack starts to come together.

One of the vertical poles of the rack is assembled.

Game Element Testing

After we had a basic understanding of what the rack was going to look like, we moved forward with game piece testing.  We experimented with how far the tubes could be thrown and discovered that a well-trained human player could likely throw tubes across the entire field.

Ryan tests a game piece.

Programming

The programming team was working hard all day.  They began the day by installing the new versioins of the programming software and then spent the day getting Onslaught to drive under driver control.  The simulator group was working on data logging, 3d modeling and collision detection.

The programming team working hard.

Design

After dinner, a group of team members met to discuss robot design.  We immediately decided on a wheeled robot and decided that at least 6 wheels would be best for maneuverability.  To save weight, we all agreed that it was not practical to consider building a robot with more than 8 wheels.  We also decided that we would like a two-speed drivetrain with a high gear to quickly traverse the field and a low gear to push other robots out of the way if necessary.

When looking at the game field, we were very worried by a 1/4″ tall plate under the carpet surrounding each tower.  The concept of a 6 wheel drive or 8 wheel drive drivertrain with dropped center wheels relies on the fact that not all of the wheels will be on the ground at all times to improve turning.  We were worried that when in proximity to the plate under the field, more wheels would be in contact with the carpet which could inhibit turning.  We thought that this might be a greater issue with the six wheel drive robots than with eight wheel drive robots, but decided to test to make sure.

We put down a metal plate under carpet and tested it with both 8 wheel drive and 6 wheel drive robots.  It was determined that the 8 wheel drive robots drove considerably better when in proximity with the plate when in high gear.  However, in low gear, both robots had great performance as if the small bump wasn’t even there.

Testing robot maneuverability on a bump covered by carpet.

We took the data from our tests and moved on to discuss how important turning near the towers would be in high gear.  It was determined that the only time turning near towers would be very necessary is when lining up to deploy the Minibot.  We decided that this is only for about 5 seconds of the match and that there is no reason to not just use low gear during this time.

After we decided that it was not important to be able to turn in high gear near the towers, we all decided to move forward with a six-wheel drive robot.  Everyone in attendance voted that the benefits of saving up to 3 pounds outweighed the drawbacks of potential limited turning in high gear when in close proximity to the towers and agreed that a six-wheel robot would be best.

The next topic that was discussed was traction.  Although with ideal physics, contact area with the ground does not affect traction, it was determined through observation that due to the tread material interlocking with the carpet fibers, more contact area does indeed result in greater traction.  Because of this, we discussed moving to slightly wider wheels in order to increase the contact area with the ground.  We were worried that wider wheels could negatively affect turning so we decided that the robot should be designed with thin wheels (similar to what we have used before) but should be compatible with wider wheels if necessary.

Finally, we discussed speed.  The consensus was that we want to be able to drive fast.  However, no decision was made on exact robot gear ratios or speed.  Both will be discussed and finalized tomorrow.

Manufacturing

As soon as it was finalized that we would be building a wheeled robot, manufacturing began on the bearing blocks to support the wheels.  All of the stock for the bearing blocks was cut and the first operation began on the outside bearing blocks.  We expect to complete the first operations on all of the bearing blocks tomorrow.

Deburring the stock for the bearing blocks.

Bearing blocks being milled.

FRC Kickoff Meeting Review

The 2011 FIRST Robotics Game Has been Announced: Logomotion

Team 254 met at Bellarmine in the morning to discuss the game.

Here are the notes from the FRC Kickoff Meeting.

Robot Attributes for Successful Gameplay:

  • Minibot
  • Score on Top/Middle/Low Pegs
  • Blocking
  • Uber Rings
  • Traverse Field Quickly
  • Logo
  • Rearrange Tubes
  • Pickup from Floor
  • Rings from Human Player
  • Follow Lines

Obstacles to Successful Gameplay:

  • Broken Partner
  • Minibot Fall
  • Opponents Block (Goals and Pickup Stations)
  • Popped Tubes
  • Wrong Logo
  • Partners in Way
  • Bad Visibility

Methods of Scoring and Defense:

  • Minibot *
  • Scoring Tubes  Everywhere *
  • Ubertube *
  • Blocking
  • Wall
  • Fast/Maneuverable *
  • Pick from Ground *
  • Pick from Human Player

* means that the method was determined to be Essential.

The Day Before Kickoff

It’s the night before kickoff and what  a productive day it’s been.

The day started out with us ordering over 250lbs of Aluminum from Coast Aluminum in Hayward.  The metal will be used to construct the robots for Team 254 and Team 1868.  Although we don’t yet know the game and don’t know what the robots will look at, we are predicting that they will have metal frames, so we bought the material to build frames.  After it was ordered, EJ and Sunshine drove up to Hayward in a NASA truck to pick up the material.

At the lab, other team members worked to put together a final list of consumable lab supplies that NASA will purchase.  Most of the items on the list were ordered today and the remainder will be ordered over the weekend.

Also at NASA, several programmers from both the simulator group and the robot group were working on various tasks in preparation for the busy robot build period.

Finally, several students worked hard to put the finishing touches on the NASA lab to prepare it for build.  The couches were cleaned and brought back upstairs and the welding table was polished to remove rust.  The field was vacuumed and shelves were organized.

9 Hours Till Kickoff
Go Poofs!

FRC Build Update

Friday the 10th marked our third and final CAD Friday and our final FRC Friday of the semester.  We had a great time and started to explore some of the more advanced assembly and sketch features of SolidWorks.  Although it would have been nice to have more time so that we could have gone into more depth and gone over more features of SolidWorks, we had a great opportunity to give many students a broad overview of the program.  Overall, I think that the FRC Friday program this semester was very successful and I hope we try something similar again in future years.

Today, we had our second Machine Tools Training of the semester with two more students getting trained on how to use the machine tools at the lab.  For reference, I’ve put up a list of the students who are trained here.  If you would like to sign up for machine tools training in the coming weeks, sign ups are here.

As the semester wraps to a close, we have very little time left to get everything ready for the FRC season.  We have scheduled Open Lab time for December 20-23.  Please sign up for this time here and come in if you are interested in working on Programming, CAD or just helping get the lab ready for build.  There are no space limitations but if nobody signs up, we will likely cancel the session and the lab won’t be open 🙁  There are still numerous items on the lab to-do list that need to get done and we need as much help as we can get.  Let me know if you have any questions for this.

Remember, students interested in CAD and programming: Coming to the workshops alone is not enough to become a CAD or Programming master.  To gain all the skills neccesary for the robot work, you will have to put in some extra time outside of the workshops.  Coming to the open lab days (mentioned above) is an excellent opportunity to get the much-needed experience with CAD or Programming.

26 Days Until The 2011 FRC Season Begins!
Happy Holidays and Go Poofs!
Nick Eyre

First CAD Friday

Today was Team 254’s first of three CAD Fridays. After a fun team lunch, we had over twenty team members come together at the NASA lab to learn CAD skills.

We started out with an introduction to SolidWorks and went into some of the skills used in basic extruded features and sketches. We discussed sketch relations and dimensioning and made several simple parts.

Later, Travis gave a presentation on the Fundamentals of Graphic Communication, which can be found here. The presentation was long, but went very well and was extremely informative. All who attended were able to learn about expressing three dimensional objects in two dimensions through engineering drawings as well as other valuable graphic communcation skills. Travis even showed the team one of his parts from his work and showed how many drawing views needed to be used to effectively communicate the part’s design.

After the presentation and dinner, we worked to develop our CAD skills by analyzing a pre-made engineering drawings and creating 3D CAD models of the parts based on the drawings. It was a good excercise for using the graphic communication skills we learned and applying them to actual design.

After the CAD was wrapped up, several team members stayed late at the lab and built shelves upstairs that can be used by our team and by team 1868 for storing and displaying our trophies and awards.

At the next CAD Friday (12/3), we will split into two teams and work on a design project, using SolidWorks to model our different solutions to the design challenge which will be announced. It should be a great way to continue to learn CAD skills through practice and problem solving.

Catapults, T-Shirt Cannon Underglow, CAD Seminar & More

Catapults

Today, at the NASA Lab, we had a large group of students meeting for FRC Friday.  This week, to apply some of the tools usage and mechanical skills that were learned in previous workshops, we split into two mini-teams and had a catapult-building competition, which was to be judged on distance launched and awesomeness (measured on a scale from one to awesome).

The two teams took radically different approaches to the challenge.  One team decided to build their catapult entirely out of metal and constructed it mostly out Kitbot parts from previous FRC Kits of Parts.  The other team decided to use Wood and PVC.  After a bit of tweaking, the metal catapult was functional and was flinging Orbit Balls across the lab.  The wooden catapult, on the other hand, did not have a stable base, and broke after being stressed heavily by the surgical tubing which powered it.  After the team made modifications and strengthened their design, they had several successful launches.

Underglow

On another note, we installed Blue LED strips to the bottom of the T-Shirt cannon to give it an underglow effect.  The strips were chosen over neon tubes for budgetary reasons.  After installed and wired, the lights looked great!

CAD Seminar

As a reminder, next week will be the beginning of our three week long CAD seminar.  We will be meeting for three FRC Fridays (no FRC friday during Thanksgiving week) to learn CAD and work on a project (you’ll find out the project if you participate).  Remember to sign up on the team website.

This Week in FRC: More Workshops

On Friday, numerous Cheesy Poofs met for our second week of the 2010 FRC workshops.  We had a huge turnout of people from 254 and 1868.  All three workshops went great.

Next Friday will mark the start of our 3-week long CAD Seminar, where we will be working in groups to learn CAD skills while working on a super awesome project (to be announced) =D.

Also, we’re starting to organize machine tools training.  Be sure to fill out the form on the event signups page if you’re interested.  More details will come ASAP.

-Nick