Editorial – 1/06/2014 – Great expectations

In the flurry of brainstorming and researching that comes with a new season’s complicated game, it’s pretty easy to forget what a Chairman’s Award is. Even after we finish a robot, we still see Chairman’s as nothing more than a dream, seeing as we haven’t established world peace, developed time travel, or started FIRST teams in any alternate universes.

This year, however, I must raise a radical proposition. This year, Team 696 has a serious chance at winning Chairman’s. We didn’t just do well last year– we excelled at both our regionals, our off-season events, and even brought our Lego robotics teams to the LA Finals. This improvement, this steady upward climb, is what Chairman’s is all about. We have every prerequisite to grab a Chairman’s Award and tickets to the St. Louis finals– all we have to do is keep it up.

For these next six weeks, business team and our glorious President Saikiran will be working behind the scenes to make Chairman’s happen. This may be the most grueling essay we will ever write in high school, but darned if it isn’t worth it.

Keep it up, everybody. St. Louis or bust.
-Jerry

Day #2 – 1/5/2014 – Manufacturing Progress

The day started at about 10AM with me taking the Canyonero, err, Suburban to Ghanal Lumber in Pasadena, where a nice gentleman cut all the pieces of plywood for the high goal for a modest fee.  Total cost, approximately $100 for the two sheets of plywood, a dozen 2x4s, and about 26 cuts.  It was a big time saver to have them cut it on the panel saw at the store.  Hopefully the field crew can get this together soon.  I brought in an air nailer, but this tool will be for adult use only (for now).

In the CNC router room, special thanks to Mr. Hoard and Mr. Widholm for finishing the awesome new dust collection system.  Check it out when you get a chance.

On the CAM/CNC side of things, I got the 1st operation of the bearing blocks programmed, which took an hour.  I decided to make the two bearing blocks in one go out of a single piece of 1×2 barstock, 5.9″ long.  There are 7 tools in all, but it’s a rather straightforward part.  Programming took about an hour, and machine setup took about an hour.  Big thanks to Mr. Widholm and Julien C. for setting up the two vises on the HAAS!

I decided to use a thread-forming tap, which is different from a thread-cutting tap.  It’s supposed to not create chips, which is what causes a tap to bind and break.  Good idea right?  So on the first part, Tap goes 0.3 down into a 0.45 deep hole, and promptly proceeds to pull the part out of the vise, and shear itself off.  Well, there went about $15.  Need to get more taps.  I knew the speeds and feeds were correct.  10-32 tap, 800RPM, 25 IPM.  What gives?

After further investigation, I found OneCNC XR5 CAM software did not post a proper G84 tapping cycle code!  It was feeding with a G01! So, we had non-synchronous motion between the spindle RPM and the feedrate.  This is a dangerous bug in OneCNC that I’ll be reporting to Patrick Matthews at OneCNCWest.  When setting up a tapping operation in OneCNC, you MUST select “Machine Cycle -> G84” NOT “Automatic cycle”.  If you select Automatic cycle, it treats the tap like a drill.

After resolving that, and a few other minor adjustments to feedrates and cutting depths, we were back in business.  I had to tweak the countersink and corner rounder tool length offsets for a good fit and finish.  1/2″ endmill roughs it out at about 100 IPM, and finishes at about 50 IPM, all at 5500 RPM. Single-flute HSS Countersink is good SLOW at about 450 RPM and 8 IPM.  Drills are drilling at 6k RPM and about 30 IPM.  Tapping at 1440 RPM and 45 IPM.  I’m still not really sold on the form-tapping, as I’m not sure if we have the same thread depth/engagement.  It may just be an optical illusion when looking in the thread.  A screw seems to fit in okay.  Total part run time is about 5 minutes for the pair.  9 good sets of two bearing blocks were completed;  enough for two robots plus one demo set. A picture of today’s progress on the bearing blocks is shown below.

bearing_block_1stop

I consider this progress to be one full day behind.

In the morning, I’ll wake up at 6:00 AM to call Fry Steel to try to get some metal on the truck for delivery for the next set of parts.

Tomorrow, I will bore softjaws to flip these over, and program and machine the backside to make the coaxial joining tube features.  Then we’ll do the 5 bearing blocks for the gearboxes out of 2×3 bar stock on-hand, then we’ll get to sprockets from 7075, wheels from 4″ round 6061, and wheel axles from 7075 PG 1/2″ round rod.

We need more loc-line and fittings and nozzles.  Two just isn’t enough for tools of all different lengths.  Also, I ordered two more ER-25 3/16″ collets, because we have a lot of 3/16″ tools we use often.

Shop closing time today: 10:30 PM.

 

Day #1 – 1/4/2014 – Kickoff Day!

Today was the first official meeting day for the 2014 FRC season!

After the morning kickoff meeting and reading the rules, we immediately started strategizing and discussed functionalities and qualities we would like to see in our robot (as discussed by Karthik Kanagasabapathy in his FRC Strategic Design Presentations).

image

We ultimately decided that we want our robot to

  1. Driving (fast and with torque)
  2. Ground Intake
  3. High Goal Shooter /Truss Thrower
  4.  Vertical Aim
  5. Passing / Herding
  6. Low Goal Shooter
  7. “Hitting Arm” (to knock stuck balls out of alliance robots)
  8. Defense Capabilities

We also want to integrate a “Dead Man’s” ball release mechanism, to allow our alliance to retrieve a ball in our possession in the event that we become disabled. We could not decide where on the list we wanted to put that, so be wrote it right next to the top four items on the list.

As for important robot qualities, we have decided to design for

  • Easy Battery Placement (We had a problem with this in 2013)
  • Protected, But Accessible, Circuit Breaker (We don’t want to break our own circuits like we did twice at IRI in 2013)
  • Strong Outer Structure
  • Quick Ball Cycles
  • Easy Serviceability

We also had the opportunity to begin prototyping yesterday. We are beginning the process with one of the most famous mechanisms from 2008, Simbot S.S.’s shooter claw.

proto-1

proto-2

proto-3

 

So far, we have been successful at shooting…. a few feet. At the next meeting we plan to add more surgical tubing and increase the travel distance for actuator.