High speed Drivetrains

[RyanCahoon]

Originally Posted by IndySam

A real fast robot is difficult to drive. Our driver Nick made it look easy because he has many hours of practice driving a fast robot.

Pushing match, what pushing match? If they can't catch you they can't push you around. It's difficult to play effective defense against a real fast robot.

Did you do any "drills" that you found particularly effective, especially in teaching your driver to avoid and react well to defense, or did you just run practice matches?

[thefro526]

Originally Posted by MICHAELABICK

You can't stall a traction limited drive

Just because you can't stall a traction limited drive doesn't mean that it won't draw near-stall current.

We've popped at least one main breaker this season due to an aggressive pushing match, and I wouldn't be surprised if a handful of other teams have as well.

[karomata]

The more experienced teams tend to better understand the large advantage that can be had when you drivetrain is fast yet maneuverable. Take 148 for example, although they do not always have the best scoring mechanism in FIRST, they continue to do exceedingly well partly because of their amazing nona drivetrains.

[PayneTrain]

Originally Posted by thefro526

Just because you can't stall a traction limited drive doesn't mean that it won't draw near-stall current.

We've popped at least one main breaker this season due to an aggressive pushing match, and I wouldn't be surprised if a handful of other teams have as well.

422 built a friction-limited 6CIM drive and popped the breaker twice at their first event after getting in an intense pushing match with the feeder station wall thanks to a miscommunication with the drive encoders.

[efoote868]

Originally Posted by PayneTrain

422 built a friction-limited 6CIM drive and popped the breaker twice at their first event after getting in an intense pushing match with the feeder station wall thanks to a miscommunication with the drive encoders.

Any idea how long you were stalling the motors? I wonder what went first, some of the 40a's or the 160a.

[fb39ca4]

Originally Posted by RyanCahoon

Did you do any "drills" that you found particularly effective, especially in teaching your driver to avoid and react well to defense, or did you just run practice matches?

Our team used our logomotion robot with our practice bot to practice playing and avoiding defense.

[AlecMataloni]

Originally Posted by Jibri Wright

I know that Team 111 had Super Shifters as well but instead of two speeds, they had three! They customly designed a third gear shift that was at a really low gear making them faster than us.

We actually used 2 speed VexPro Shifters with a 3rd stage provided by WCP which matched our desired speeds for 6in wheels. Sorry if you were misinformed.

[its da PAT!!!]

Originally Posted by RyanCahoon

Did you do any "drills" that you found particularly effective, especially in teaching your driver to avoid and react well to defense, or did you just run practice matches?

We don't really focus on defensive drills. But our driver knows the robot and I simply tell him whats going on with other robots. Then in his crafty mind, he'll decided where to go. But to tell you the truth, he'll sike me out a lot....

[pmangels17]

This year 271 went with the most intense custom transmission we have ever done. 6 cims, on a two speed shifter, geared for roughly 16 fps in high speed and 6 fps in low speed. Also, we have a Power Take Off for our climber, but our drive is ridiculous. We push robots sideways with all our torque, and we can race around the pyramid in high speed. Also, we went up against a bot with mecanum wheels, and pushed them twice all the way around the pyramid. Simple 6 wheel dropped center, with double wide center wheels, all 6 with roughtop tread. We peaked at 314 amps one match, but it was only for a split second, so we were fine. We have ammeters on two of our drive motors, so just multiply by three to find total amps. Oh, the pushing. I'd say that for any team that even just wants to upgrade from the kitbase, add a two speed shifter, the versatility lets your robot do so much more, and if used right, it gives you a lot more options. We have used two speed drives many years. We didn't in 2012, but for the years that I participated in so far, 2011, 2012, and 2013, we had 2 speed drives. We haven't had many problems at all.

[TheMadCADer]

Originally Posted by karomata

The more experienced teams tend to better understand the large advantage that can be had when you drivetrain is fast yet maneuverable. Take 148 for example, although they do not always have the best scoring mechanism in FIRST, they continue to do exceedingly well partly because of their amazing nona drivetrains.

I should point out that 148 has been using a slightly different version of that style of drivetrain in 2011 and 2013 (in 2012 they used a fairly standard tank drive), which they call a butterfly drive. It's pretty much the same as a nona-drive, but there is no perpendicular omni-wheel. It allows for similarly 'drifty' driving, but no strafing. In 2011 they also liked being able to toggle their traction wheels down in order to drive in a very straight line during autonomous.