Spin up turrets?

Why do people keep talking about making turrets, I understand the benefits of having one but for vex it just seems unnecessary. lining up with x drive would take the same amount of time in my mind.

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joke probably
(20 char)

Pros:

  • Can point at goal while driving and intaking discs. X-drive wouldn’t really be able to point, shoot and intake all at the same time without some difficulty. Not impossible very possible acutely but challenging
  • Its a really cool challenge as there is not much stuff in the vex world that is related to turrets.
  • Would be very fun.

Cons

  • Going to be difficult to build.
  • Code might be difficult (not really sure, but seems like it could be)
  • if using GPS sensor for anything cool like pointing at target the whole time the field needs the GPS which is up to the EPs desertion.

These are the ones that I have been think of. The fun and challenge of building something new and exciting is 100% wins it over for me to at least think about and maybe try.

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it is not a joke actually.

think maybe you can just go to youtube and take a look at the amount of pushing around during nbn and tp? This will give you a better idea of what to expect in a shooting game :slight_smile:

and here you go - All About The Robot - VEX Nothing But Net 323Z Pre-Competition Reveal - YouTube

turret for nbn.

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Imagine you are racing for the discs, intaking them and shooting them into your goal.

Without a turret, the cycle time for disc picked up and shot into goal would be relatively great. You would intake, turn the robot using the drive, shoot, and turn back around to intake more discs.

A more seamless solution would to use a turret. The robot can intake discs by driving forward, while the turret would shoot the discs in another direction. This would allow for the intake of discs while simultaneously shooting, allowing for much faster cycle times. Disc in, disc out. No turning the drive to reposition. An example of this situation is crudely drawn out below. image

As mentioned by @meng , there will likely be some pushing occurring during the match. A turret would be able to adjust to most of the collisions that non-turret shooters would be thrown off by.

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People are just excited to think about building new mechanisms for the new game. Similarly to how everyone was taking about pneumatic transmissions last year and barely anyone ended up implementing them.

Realistically, only incredible designers/builders with access to precision machines to make custom gears and bearings would be able to make an effective turret. Teams would also have to have pinpoint accurate odometry with barely any drift to have the turret constantly aiming at the right area.

Even so, I believe most high level teams will avoid turrets anyways because the time spent designing and tuning a turret could be better spent practicing driving and tuning other more essential subsystems(flywheel, indexer, intake, endgame mech).

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new sensors? GPS sensor kinda removes odom to some degree and vision sensor you could just point at the target.(you wouldn’t know the power that you need to launch at)

But gps is only in skills so you’d still have to rely on odometry to be accurate in match play. Odometry is also arguably one of the easier parts of making a turret work as plenty of documentation exists on odometry, while there’s next to no documentation for making a turret in the context of vex parts.

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just have a 2nd controller and have them point the joystick in the direction the robots facing, then the robot can use that data to aim the turret

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In my experience, the GPS sensor has been EXTREMELY inconsistent in giving accurate position readings. It could be that I set up my GPS strips weirdly, but the x and y coordinate reading ranged plus or minus 200 millmeters from my location (1000 to 1400 at 1200, for example) The heading (or rotation around 360 degrees) was accurate though, with inconsistencies starting at around the hundredth place (eg 25.55 could be 25.54… so extremely accurate)
I can get a video of this happening (the controller, brain, or SD card spitting out readings constantly) if you’d like me to, as well as how I have it set up

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This could be a really useful resource to teams like me who don’t have a GPS sensor yet and are thinking about getting one. The accurate angle is really appealing to me as I have alway been thrown off by the gyro drift and such. A thought that I had would be to use possibly 2 GPS sensors and average their position one for the angle of the robot and one for a turret.

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And there was also 1826 who used odometers and complex sensor usage to dynamically change the turret position and flywheel rpm as the robot moved around the field. And I bet now with the vision sensor (and other, non-VEX sensors like the Limelight for VEXU) teams could leverage both that and odometery to have an auto-aiming turret. But honestly with the amount of defense in this season’s game, I’m not sure how viable they are going to be.

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Impressive. Bet there must quite a few odometry wheels running below.
But the cycle time will need to be faster in order to match up all those dome-going teams.

That said, and as mentioned by you, this approach might be more viable for the VEXU teams (that have access to faster respond time sensors, etc). It will be difficult for HS teams.

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I don’t see a turret being a widespread feature of robots this season, it seems very difficult and the benefits aren’t super important I think.

There are 60 discs on the field, and I am skeptical if even half of them will be able to fit in any one goal. So I don’t see disc shortages being too much of an issue actually. If your opponents are that much faster than you at intaking, they could begin to put discs in the low goal and protect them before you have come close to filling up your goal, but if it gets to that point in a match, your opponents are just simply better than you and will likely win.

perhaps teams will continue shooting at the goal even when it has begun to overflow, just playing the odds and hoping that their shots will stick when half the time they’ll just slide off the full goal. But I think once teams have filled the goal to the brim, they will begin camping out the rollers to prevent opponents from being able to change them.

at any rate though, I don’t see shooting efficiency actually being all that important for matches. To me it seems like as long as it’s good enough to fill the goal in the first minute or so of the match, which I believe a non-turret bot alliance is fully capable of, then it will probably be good enough. Similar to ring scoring this year, you had like a minute to fill an alliance goal, and so even if your ring conveyor wasn’t the pinnacle of efficiency, as long as you could fill that goal in the time you had, it was good enough.

But I would love to see some of the top teams attempt a turret bot and have success with it, I can definitely see the merit of having one, even if it probably will not be necessary.

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Something I did to make the reading more accurate was to take a lot of readings (100 or so) and averaged them all. This generally got within 30mm of my position
As for the results, I can see if i can get those sometime soon

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It appears @RoboCatz beat me to the fuze, but here are two turret bots that were built in NBN

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or vision

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Turrets do seem like a over complicated, waste of time, but I could see them being extremely useful mainly in skills. The ability to drive and pick up disks while shoot presents a huge advantage in time savings.

My main motive for making a turret is it would be really cool, and I would love to take on the challenge of designing it. But practically I think it could really improve accuracy.

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Building a turret with code that actually lets u shoot on the move is hard >> only a few teams in frc rapid react did it i think

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Here’s the innovate award winner form that season as well:

They also won their divisional create award as well.

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