675A Robot Reveal

So people… I know you have all been waiting for this. Here is our 2012-2013 robot:
https://vexforum.com/wiki/images/6/63/675A_RobotReveal_Picture1.jpg

The Drive Train
https://vexforum.com/wiki/images/d/dd/675A_RobotReveal_Picture8.jpg

The Arm
https://vexforum.com/wiki/images/f/f6/675A_RobotReveal_Picture2.jpg

The Scoop
https://vexforum.com/wiki/images/b/be/675A_RobotReveal_Picture10.jpg

Scoring
https://vexforum.com/wiki/images/f/fd/675A_RobotReveal_Picture9.jpg

Specs
Drive Train:

  • 4-393 Motors (Speed)
  • 4" Omnis are chained for optimal torque transfer
  • If chain breaks, robot can still drive (motors connected to wheels)
    Arm:
  • 4-393 Motors (Speed
  • 15:1 Compound Gear Ratio
  • Movement range about 270 degrees
  • Can unflip robot in case of flip
  • Lifts up to 10 sacks
    Scoop:
  • 1 solid piece of 1/16" polycarb
  • 17.5 inches wide to allow greatest area for picking up sacks
  • Can hold ~12 sacks
    Scoring/Descoring:
  • Can score in a trough in about 2 seconds
  • Can descore a full trough in less than 2 seconds
  • Can score anything in the highgoal (even robots)
  • Not limited to scoing forward or backward

We have had this robot built since October 17, 2012 and have therefore been able to take it to 3 competitions. Of those 3 competitions and 41 matches, we have only lost 5 times. 2 of these times was from IME glitches discussed in this thread: https://vexforum.com/t/possible-problem-with-robotc-3-54/22882/1 Our robot is a very fast, efficient robot that is able to lift close to 10 sacks and score them within a couple of seconds. Also, our ability to descore a whole trough in 1-2 seconds allows us to completely change a game’s momentum. We have a total of 6 autonomous which allows us to change and adapt to the situation as needed.

  • Our average score per match is 172 points whereas our opponents is 68.
  • We can score 280+ points in robot skills (number 1 in the US)
  • Our average autonomous score is 50 points
  • We have had close to 110 hours of driving practice (5 hours a week)
  • Had close to 30 hours in autonomous.

More pictures here: https://vexforum.com/wiki/Team_675A

Let me know what you guys think of our robot…

Looks great. Do you guys have any video of the robot in action?

We look forward to seeing you guys at Worlds!

Rik, there are plenty of videos on youtube of 675.

Ultra low COG, great reach, beautifully simple design. Like it :slight_smile: All your teams will go well.

Good luck, Paul

Thanks. Our whole goal for this robot was to make it simple and efficient. We didn’t need anything fancy that would just end up breaking later in the competition. We also wanted to make it super easy to drive. The driver doesn’t even have to take his thumbs off of the joystick to score anything. We believe that this has been what has made our team so successful.

Good luck to you as well.

Very nice robot! Does the lack of a left side encoder cause any problems in autonomous?

What we do is use our gyro to keep the robot straight. We used to have 2 encoders on the robot but discovered that it doubled our chances of one failing or static discharging through the power lines. Using the gyro, we believe, is more reliable because of wheel slip. It does however accumulate drift, although very slowly.

That makes sense. Thanks! I’m excited to see this robot at worlds (6 days left!)

Why did you chain up the drive when the motors are already directly driving the wheels.

We found that last year when we just direct drove, our front wheels were spinning a lot and we were stalling our back motors a little. However, if the chain was to break, our robot could still drive.

I love the strategy of a simple well designed robot that is efficient and has great programming and lots of driving experience.

I am very impressed with the programming that you guys have done.
look forward to seeing you at worlds!

I you haven’t seen it already, here is our scouting database. It can run completely offline and will show as many competitions as you want. https://vexforum.com/t/robodragons-scouting-database/23500/1