Re: Team 2363 turret actution
 

Is 1718 able to accurately shoot into a hoop while driving away from it? I'd love to see the video, if you're willing to show it.

I never said it wasn't possible, however it's unlikely, and easy to mess up.

Re: Team 2363 turret actution
 

Understood, however I don't understand your logic behind the no front/back thing. You can't just drive your car backwards on a freeway and say it's forwards. For the most part, robots are going to have a designated "front" and a designated "back". That means when you go forward on your controller, your robot will go forwards.

I agree. Your robot itself is capable in moving every which direction it wants. So why have a totally separate part of the robot that turns independently of your robot when you can turn your robot just as easily in any way it wants? Unless your robot can hardly turn, or you haven't considered the robot's orientation a factor during the match, turning a robot 180 degrees is the same as turning a turret 180 degrees, if not faster since most drives are powered by 4 CIMs, whereas most turrets are going to be powered by one of the weaker motors. I've seen robots turn 180 degrees pretty fast.

As for limiting actions, isn't that what engineering is all about? Tradeoffs. Torque vs speed is my favorite one. And sometimes you end up limiting things you don't really need anyways.

As for your Murphy's law example (My favorite law :D), there are so many ways to engineer your robot so that doesn't happen, and good driver training will easily be able to fix a ball in an awkward position.

I'm not at all saying turrets are bad, and love all of the videos that are being posted. Just that there are ways to make an effective robot without turrets.

Re: Team 2363 turret actution
 

How did you cut your teeth?

Re: Team 2363 turret actution
 

Precision. To make an accurate long distance shot, the yaw angle must be controlled very precisely. During concepting, we knew we could design and fabricate a turret which could mechanically aim very precisely. We suspected that control of the shooter yaw angle via the drivetrain might not be very precise. The software can be written so the vision system can set shooter yaw angle by controlling either the drive train or the turret. We decided to go ahead and built a turret as a reasonable response to reducing technical risk. If it turns out that yaw control of the robot gives us everything we need, we'll keep the turret locked and only use the drive train. On the other hand, if the drive train is unable to position the shooter precisely enough, we have the turret actuator to fall back on, even if it doesn't rotate a full 360 degrees.

If, by some miracle, the computer runs fast enough, and the software is good enough, it is conceivable that we could keep the shooter locked on the target with an accurate "firing solution" such that we just drive around picking up balls and firing them continuously through the hoop, on the move. Can't do that without a turret.

As a mechanical guy, I always want to say, "The robot would be so much cooler if only the software could do ..." I never want to hear, "The robot would be so much cooler of only it was mechanically able to do ..." Of course, both software and mechanical people will always say, "If only the drivers were better, the robot could do ..." and the drivers will say, "If only we had the robot sooner to practice with, we could have done ..." Such is life when asked to do the impossible with too little time and not enough money.

Re: Team 2363 turret actution
 

Please do that! I wanna see that so badly!

Re: Team 2363 turret actution
 

You and me both. I've been harping on the software folks to stick a laser pointer on a pan/tilt, mount it on last year's robot, and show they can hold the red dot in the center of the vision square while the robot drives around. If they can do that, we can make baskets on the fly. That's the video I want to see posted on youtube.

Re: Team 2363 turret actution
 

One of our sponsors is a sheet metal fabrication shop. So we drew it in SolidWorks and they made it for us. They make several and we sandwich them together with rivets to yield cheap aluminum gears of any size or shape. We "borrowed" this technique from the RoboWranglers.

HTH