Shooters vs Arms

[t-raum]

A shooter I think is the best way to go even during end game. As long as you have a device that can knock the ball off the overpass at the end. The shooter can hurdle and then knock te opponents ball off the overpass to create a 22 point gain for the alliance who can do this. If a team can pull this off end game would be very interesting.

[Captain Sugar]

our shooter is almost like an arm in its attributes. it can pick up the balls really easily, using a set of rings on the front. however, when it shoots, the pneumatics contraption pushes out too far and actually pushes the robot off the ground, so we can't shoot on the go. it shoots the ball really far, though.

[Bomberofdoom]

What about an arm that can kind of act like a shooter?

Our robot has a claw system that grabs the ball from the floor and then the arm goes up about 70-80 degrees while the claws themselves rotate to be horizontal. We can drop the ball onto the overpass but we're not sure it can go over the overpass easly.
That's why we're trying to implment a function in the programming area that will bring the arm back 135 degrees(!) and once the robot is in position and the button has been pressed, the claws will rotate at full speed and will release the ball in the midst of the whole action which will cause the ball to fly over the overpass.

Now, I'd call that a thrower, which can count as a combination of an arm and a shooter.

pros?
- Doesn't have to position itself specificly in order to make the ball pass the overpass.
- Cannot be blocked.
- Can put the ball on the overpass.
(- can catch the ball on the run.) - to be tested.

Cons?
- it can take about 6-5 seondes to get the arm and claws in shooting position, might be some disadvantage.


There's probablly more that I just can't point them out 'cause I haven't went through them yet...

Your opinions about this?

[ALIBI]

Shooters have the advantage. Most arm bots will have to stop moving before they can hurdle the trackball and they are limited as to where they must be in the home zone (close to the overpass) when they lift and hurdle the trackball. A good shooter will be able to hurdle the trackball on the fly from at least a third of the floor space in the home zone. Several people have talked about a shooter not being able to pick up a trackball as fast as an arm bot. I believe that you will have shooters that can pick up a trackball just as fast as any arm bot out there. Placing the trackball is way over rated. Given the speed of a shooter vs an arm bot that places. The shooter should be easily able to get more hurdles than an arm bot to make up for a single 12 point placement. Also, you will never see a shooter get clothes lined by the overpass.

IMPEDING: Preventing or obstructing an opposing ROBOT’S ability to proceed around the TRACK in the direction of traffic.

As for blocking a shooter, all a shooter has to do is head directly towards the blocker, just before it gets to the blocker, veer left or right and launch, if the blocker moves to get back in front of the shooter, the shooter just earned negative points for impeading.

[Eye-gor]

Originally Posted by ggoldman

Here are some pros and cons I see of both:

Shooters

Pros:
Quick release
Can hurdle "on the run"

Cons:
Cannot Place on Overpass at end
Can be "Blocked" easily
Cannot (on their own) knock down balls off overpass

Arm lifters

Pros:
Can knock balls off overpass
Can place on overpass at end of game
Cannot be "Blocked" while hurdling

Cons:
Slightly slower than shooters
Possible High Center of Gravity

But you haven't gone through all the possibilities. the hardest part of this year's game (design-wise) was choosing a direction to take, whether we'd catapult the ball, or use an arm...or a combination of both.

[jimbot]

You can't really block the ball. unless Im mistaken there is a rule prevnting oppossing robots to be over 5 feet in your home stretch.
As for shooter vs. arm, please watch lower video. If 118 can remove over head ball, then they will be amazing using that SHOOTER!

http://ca.youtube.com/watch?v=CAJBC-DDL9w

[EricH]

Originally Posted by jimbot

You can't really block the ball. unless Im mistaken there is a rule prevnting oppossing robots to be over 5 feet in your home stretch.

You are mistaken. Please read the current edition of Section 7 and Updates 1 and 2.

There is now no height restriction, other than the physical limits of the Overpass.

[hipsterjr]

I think the biggest con with shooters will be air usage (assuming most are using pneumatics). Ours has 2x 2" and 2x 1.5" by 10" cylinders. After a launch our air tanks loss a lot of air, but can still operate at 50+ psi. 1726 has has provided some great advice on air conservation in a couple threads. As long as teams can keep air in their tanks (and a little in the cylinders ) Shooters will dominate the field.

side note: even if some teams have air problems, strategy could compensate for their recharge time.

[XXShadowXX]

I personally like the arm bot for the reason that our robot was designed with plug and play in mind, we wanted to in case of mistake or error be able to remove that whole 'arm' assembly, and replace that with a bumper/herding device. To answer your next question, yes we are that far under wieght, 835 holes pre cut, 95 lbs W00t!

[Doug Leppard]

In the scrimmages, has anyone seen how shooters did especially as related to arms?

[Chris]

In my humble opinion the entire game is ball acquisition...it doesn't matter what your method of getting the ball over the overpass is....The teams that are best at grabbing it quickly will be the best teams hands down...

[waialua359]

I agree with this. Effectively grabbing the ball quickly and moving around the field to get in position to score is important.
The one thing I keep hearing from all these threads is that, if you lose autonomous by 15-20+ points, its too hard to overcome if both alliances can fairly hurdle, herd, and do laps.
I'm not so sure if even the best hurdler on an alliance can overcome 20+ points, when everyone else can score, there will be traffic, and only 2 balls per alliance.

[martin417]

A well designed shooter (IMHO) can outscore most arm designs. It should be able to:

Acquire quickly.
Shoot on the run.
Avoid legal blocking maneuvers.
Place the ball on the overpass.

I know of at least one such arm.


http://www.youtube.com/watch?v=QeQSGmFnKAE

One big problem with arms is the CG. While lifting the 8+ pound ball 6 1/2 feet off the floor, the CG is very high. I saw several arm bots go turtle at the scrimmages.

[PhilBot]

Originally Posted by s_forbes

Who says a shooter robot can't take a ball down and put it back?

You mean like this: http://www.youtube.com/watch?v=T5d34yZrSH0

[waialua359]

Originally Posted by martin417

A well designed shooter (IMHO) can outscore most arm designs. It should be able to:

Acquire quickly.
Shoot on the run.
Avoid legal blocking maneuvers.
Place the ball on the overpass.

I know of at least one such arm.


http://www.youtube.com/watch?v=QeQSGmFnKAE

One big problem with arms is the CG. While lifting the 8+ pound ball 6 1/2 feet off the floor, the CG is very high. I saw several arm bots go turtle at the scrimmages.

I think it depends on the bot. I'm pretty sure some bots will be very stable while lifting and scoring. We throttled full speed from dead rest with our ball straight up in the air (and vice versa), and our robot does not tip at all.
I'd be more scared of a shooter launching a ball dead square on our bot, although I think we would survive. Some of the bots that I have seen have ball grabbers that look so flimsy like they'll break with a little impact.