Driving is arguably one of the most influential factors in how well you perform. There are many techniques, tricks, and mistakes that we all use and make on a pretty much daily basis. Some of these would have been great to know when marginally starting in vex, like not switching directions from -127 to +127 on turbo motors too often, or making arced turns as opposed to angles turns.
What are some of your favorite techniques when driving? Some of your worst driving failures and mistakes?
Worst mistake is driving forward at full speed, then reversing suddenly. I still remember the cracking sound…
I do this all the time with my current robot. No cracks here except for maybe the loose chain. You just have to make sure all the gears in your base motors are not shredded and properly set in place.
Oh, just wait for it it can take a while, put it can come back to bite you:)
We had to replace one motor on our drive because the clicking sound turned out to actually be a crack in the gear. Then I realized that on top of that, half our drive axles weren’t actually in the motors, which would explain why it was so slow during testing.
One thing I’ve found helped is not always hitting walls, the low goal, or other robots at full speed. It starts to wear down on your robot over time.
The sheer amount of vex net keys that come loose in collisions hurts me physically. Then teams just stand there wondering what the heck just happened.
I should probably tie mine down so we lose connection less. You guys would shoot me if you saw where my vexnet key was.
You mean with a ball, right? That being said, I’ve seen some upside down vex-net keys that make me cringe far more.
Driving techniques will differ hugely based on the type of robot you are driving, and the way the controls are programmed. I was (the U.S. Open was our last competition) our team’s main driver, and we had a 6 motor turbo drive, and could shoot from midfield and full court, with our specialty being preloads. One thing that I found amazingly useful was a way to “shift gears” on the robot. We did this through programming, with one setting making our drive base move at full speed, and the other at approximately half speed. This let me be far more exact when lining up to shoot, especially with preloads. Having important buttons be close together is also helpful, so you can reposition, and hold the button to (for example) start up your flywheel at the same time.
Pinning is also a technique that should be used tactically. Especially in matches where you are trying to prevent an elevation attempt, pinning can be essential. Typically, when and if I go for a pin, I usually hold for about 3 of the ref’s counts before i start to ease off, thus giving me some time to get back. Obviously, you have to be careful with this, so as to avoid a DQ. However, if you do it right, you can either delay them for long enough to prevent them from shooting some balls, or achieving a lift.
Also, one thing I’ve noticed is that many teams this year have somewhat weak drive bases. I’ve encountered a number of teams whose drive bases will burn out, especially after a pushing contest against my team’s 6 motor drive bot. This can also be used tactically, as if you can cause your opponents to burn out (without doing anything illegal) then you now have the upper hand.
You can achieve this same result by using mapping the inputs from your joystick to your controller in a non-linear way. If someone from Exothermic Robotics sees this, considering posting your exponentially-smoothed driving code. EXO’s been using it since 2007 and it works really well.
I have been a long time fan of Jordan’s joystick remapping. I would recommend everyone read
https://vexforum.com/t/24cs-motor-control-value-remapping/23959/1
I agree
Also works well for position or velocity control applications, not just driving.