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Ginger Power 13-01-2017 12:07

Value of a Turret in STEAMWORKS
 
Is a turret worth it in STEAMWORKS? It would allow for quick and fine side to side adjustments on a shooting mechanism that would be more accurate than turning your drivetrain. You can continue to shoot even while pinned at awkward angles as well as many other benefits.

Some cons are that turrets add complexity, it would be hard to use a turret in combination with a wide drum shooter, and there is a perfectly good wall to park against in the key.

When considering shooting volume is far more important than shooting accuracy, is a turret worth it?

GreyingJay 13-01-2017 12:19

Re: Value of a Turret in STEAMWORKS
 
1241 had a great turret based high goal shooter for Stronghold. At first they would stop anywhere on the field in front of the batter to line up the shot, but teams playing defense quickly learned to disrupt them. So, they started driving up to a wall before lining up their shot, to reduce the impact of defense.

It took a second or two for their camera to acquire its target and align the shooter. For Stronghold this was fine, and rather necessary since if you missed your shot, you had to start all over again. But if the intent is to unload a hopper full of 50-100 balls at high speed, then I question whether it's worth it. In the time it takes to aim the turret you could just as easily start firing and adjust the robot itself.

BAB the Builder 13-01-2017 12:28

Re: Value of a Turret in STEAMWORKS
 
If you are infact using a high speed shooter to unload 50+ fuel in just a few seconds, by the time you have fired, realigned, and continued firing you could have just as easily lined up using a vision tracking/turret, or just have a specific place on the field to shoot from. If you adjust while shooting you would have only a few fuel left in your bot to make much of an impact once lined up.
In 2016 teams would slam into the tower to have a physical lineup or in 2013 when teams would lineup with the pyramid. although not the most elegant strategy, its quick and effective.

Im assuming you are wanting the most points/time spent shooting so although volume is more important than accuracy, there is still a benefit to making the shots count.

Cothron Theiss 13-01-2017 12:41

Re: Value of a Turret in STEAMWORKS
 
I think the biggest problem with using a turret shooter is the packaging issue. As we've already seen from Ri3D, one of the best ways of packaging a single shooter wheel with a big hopper is to place the wheel beside the hopper along the width of the robot. But if you want a turreted shooter, you're either taking up a lot of space from your available hopper, putting both the shooter and the hopper on the turret together, or doing something even crazier like using the turret inside of the hopper as an integrated agitator. Frankly, I think all of those options are far more trouble that it's worth. Also, I think it'll be very worthwhile for dedicated Fuel bots to be able to catch and recycle their missed shots, and a turret design makes that much more difficult.

Lil' Lavery 13-01-2017 12:54

Re: Value of a Turret in STEAMWORKS
 
Are you attempting to build a single stream flywheel shooter with the capability of hitting shots from range while another team is parked in front of the boiler? In that case, I could buy an argument for a turret.

onenerdyguy 13-01-2017 13:16

Re: Value of a Turret in STEAMWORKS
 
5929 has a functional turret prototype at the moment, and are finding that while it's nice, it isn't worth the hassle. It's currently taking approx 3x longer to get a solid aim and empty the hopper from range as it does to just drive up to the low goal, and unload to the high goal from there.

We're deciding today which way to go. I have a feeling we'll have 2 groups both developing them independently.

euhlmann 13-01-2017 13:37

Re: Value of a Turret in STEAMWORKS
 
It's a lot of robot real estate taken up for not a lot of benefit. You have only 1/3 of the field to shoot from, and most of it is blocked by the airship after all. I see much more benefit in using the space for 2 shooters

GreyingJay 13-01-2017 13:39

Re: Value of a Turret in STEAMWORKS
 
Quote:

Originally Posted by euhlmann (Post 1630577)
It's a lot of robot real estate taken up for not a lot of benefit. You have only 1/3 of the field to shoot from, and most of it is blocked by the airship after all. I see much more benefit in using the space for 2 shooters

Or a larger on board hopper.

NathanStro 13-01-2017 13:41

Re: Value of a Turret in STEAMWORKS
 
I would think it is too big a solution for the problem. Just my opinion though.

IronicDeadBird 13-01-2017 14:50

Re: Value of a Turret in STEAMWORKS
 
Turret is too much real Estate taken up, you could alway just use an omnidirectional drive base.

Jarren Harkema 13-01-2017 15:58

Re: Value of a Turret in STEAMWORKS
 
Quote:

Originally Posted by IronicDeadBird (Post 1630656)
Turret is too much real Estate taken up, you could alway just use an omnidirectional drive base.

Arguably an omindirectional drivetrain provides many disadvantages without addressing the advantage of a turret. Good luck trying to align your omni or mechanum drive while being shoved sideways.

Evaluate all of your needs to play the game, and then find the best way to address those needs by weighing the pros and cons of a design.

bt20304 13-01-2017 16:08

Re: Value of a Turret in STEAMWORKS
 
Quote:

Originally Posted by Jarren Harkema (Post 1630703)
Arguably an omindirectional drivetrain provides many disadvantages without addressing the advantage of a turret. Good luck trying to align your omni or mechanum drive while being shoved sideways.

Evaluate all of your needs to play the game, and then find the best way to address those needs by weighing the pros and cons of a design.

While i agree that an Omni drive train allows better lateral movement, you should think about defendability of a robot on all omni's. That's gonna take a lot to stay put, eventually your battery will dip due to continual load, and when it dips, your shooter could stall as our shooter did in Stronghold!!! :ahh:

How you package the turret depends on your design and intake, but they can be quite small. As for aiming, our team student captains thought about keeping turret aimed at boiler the duration of match, and using vision only when line of sight and when readying shooter. wouldn't take much. Just a thought though, haven't investigated too much.

GreyingJay 13-01-2017 16:28

Re: Value of a Turret in STEAMWORKS
 
Quote:

Originally Posted by bt20304 (Post 1630715)
How you package the turret depends on your design and intake, but they can be quite small. As for aiming, our team student captains thought about keeping turret aimed at boiler the duration of match, and using vision only when line of sight and when readying shooter. wouldn't take much. Just a thought though, haven't investigated too much.

One idea that we had for Stronghold but never fully pursued was the ability to keep a turret always aimed toward its intended target no matter what the rest of the robot is doing. If you've got a gyro on board then you know what your heading is, and if you know what your starting position was relative to the boiler, then you can move the turret accordingly. Encoders should provide a "good enough" direction such that a vision system could take over when you need to fine tune the aim.

We had our camera mounted on a servo pan/tilt unit and the working idea was that the camera (instead of a turret) would always try to face the tower, so that when we were ready to aim, it would be reasonably easy to find the vision target. Ultimately we opted for a fixed camera angle to keep the code simple as we ran out of integration time.

IronicDeadBird 13-01-2017 21:09

Re: Value of a Turret in STEAMWORKS
 
Quote:

Originally Posted by Jarren Harkema (Post 1630703)
Arguably an omindirectional drivetrain provides many disadvantages without addressing the advantage of a turret. Good luck trying to align your omni or mechanum drive while being shoved sideways.

Evaluate all of your needs to play the game, and then find the best way to address those needs by weighing the pros and cons of a design.

Omnis and mechs aren't the only thing that can be pushed around. While a more traditional drivebase might be pushed around less I have yet to see a robot that couldn't be pushed.

From the information I read it tackled the following issues.
1. Turrets add complexity
2. It would be hard to use a turret in combination with a wide drum shooter
Going omni does directly contradict the following part.
"It would allow for quick and fine side to side adjustments on a shooting mechanism that would be more accurate than turning your drivetrain"
Which I completely agree is a real issue but with drive practice that can be minimized (not eliminated but minimized).
Due to the nature of bumpers your ability to shoot "when being pinned" is completely up to the two robots geometry so omnidirectionality does not tackle that issue the way a turret does. That being said re-positioning is a lot quicker when you can strafe.
The final statement that is made does contradict the whole quick and fine side to side adjustments.
"When considering shooting volume is far more important than shooting accuracy, is a turret worth it?"
If you don't care about accuracy as much as volume then don't worry about the turret anyway.

dirtbikerxz 13-01-2017 23:40

Re: Value of a Turret in STEAMWORKS
 
Quote:

Originally Posted by IronicDeadBird (Post 1630880)
Omnis and mechs aren't the only thing that can be pushed around. While a more traditional drivebase might be pushed around less I have yet to see a robot that couldn't be pushed.

There is a difference between being pushed around just by barely being touched, and having to have a robot ram you to be pushed. There is a HUGE difference in the force needed to push a omni wheel only bot sideways, and a bot with 8 - 4in diameter 2in thick colson's being pushed sideways.

EricH 14-01-2017 00:08

Re: Value of a Turret in STEAMWORKS
 
Quote:

Originally Posted by IronicDeadBird (Post 1630880)
While a more traditional drivebase might be pushed around less I have yet to see a robot that couldn't be pushed.

I have, in video if not in person.

Robots from the early 2000s could be very good at not being pushed if they didn't want to be. Admittedly, many of the tactics used at that time are no longer legal, but the fact remains that anybody trying to push 71 in 2002 lost.


One tactic that is still legal (if your bumpers won't violate the zone when you do this) is to have a plate on the bottom of your robot covered in, say, blue nitrile tread and actuated by something so that it drops below your wheels. You could also raise your wheels and put all that blue nitrile on the bottom of your frame instead--same result. I want to say I've heard of this strategy being used in shooting games, too. Line up, drop, empty, raise, reload, repeat.

gorrilla 14-01-2017 00:49

Re: Value of a Turret in STEAMWORKS
 
Quote:

Originally Posted by EricH (Post 1630936)
I have, in video if not in person.

Robots from the early 2000s could be very good at not being pushed if they didn't want to be. Admittedly, many of the tactics used at that time are no longer legal, but the fact remains that anybody trying to push 71 in 2002 lost.


One tactic that is still legal (if your bumpers won't violate the zone when you do this) is to have a plate on the bottom of your robot covered in, say, blue nitrile tread and actuated by something so that it drops below your wheels. You could also raise your wheels and put all that blue nitrile on the bottom of your frame instead--same result. I want to say I've heard of this strategy being used in shooting games, too. Line up, drop, empty, raise, reload, repeat.

I remember seeing a video or clip of a robot that achieved this concept with the pivoting Octo-drive modules that have been available for a few years, can't find it though.

IronicDeadBird 14-01-2017 01:43

Re: Value of a Turret in STEAMWORKS
 
Quote:

Originally Posted by EricH (Post 1630936)
...have a plate on the bottom of your robot covered in, say, blue nitrile tread and actuated by something so that it drops below your wheels. You could also raise your wheels and put all that blue nitrile on the bottom of your frame instead--same result...

I saw that once wasn't sure if it has an official name that is recognized on Chief Delphi, the team I saw doing it called "gastropod drive" was back on Aerial Assist, in the wild pits of a Utah regional. Does it have an official name?
Anyway those teams must have been really worried about being pushed around.

Ginger Power 14-01-2017 02:02

Re: Value of a Turret in STEAMWORKS
 
Very helpful thread, thank you. 4607 has decided against a turret for now which has helped to simplify many aspects of the robot.

ShIfTiNgBoT 14-01-2017 03:49

Re: Value of a Turret in STEAMWORKS
 
If you have faith in your team and its resources to be able to design and manufacture a turret, then yes, go for it. If you think that you can't control and tune it enough to be as accurate as a fixed shooter, don't.

bEdhEd 20-01-2017 22:50

Re: Value of a Turret in STEAMWORKS
 
Well, after 2 weeks of hard work prototyping two wildly different shooter designs, 701's students have decided to lock in on the turret idea that takes the best elements from both prototypes and puts them together into one design. We feel very ambitious this season, both in strategy and build execution. They have determined that the turret will be valuable for our strategy, and I have the confidence in our students to get it working as we want it...but you might have to wait for the reveal video to see how it goes. :yikes:


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