Launchers VS Arms

Inspired by this post - I’m curious what others think about the advantages/disadvantages of either design. Strategy wise , physically or whatever. And who’s just going to flat out score the most?

This thread might help you out, Dan.:slight_smile:

I think the best alliances in the finals will consist of 2 arms bots and 1 launcher bot.

As good as launchers can be, they are still dependent (in most cases) on arm bots to remove the trackball as well as place the trackball during the endgame.

I do think launchers though will be the high scoring bots of the regional. However, they may also receive more defense.

Bah! Thanks, didn’t see that…

I personally think it is way better to have a launcher although it is not the best solution in terms of safety.

Therefore, my team initiated a ‘Safe Shooter’ campaign to make sure all the teams which compete in Tel Aviv regional, as well as all the other regionals worldwide, comply with FIRST safety rules.

We have copied the rules and organized them into a small and simple presentation.

You can access and download it at:

http://www.chiefdelphi.com/media/papers/2082?
‘Safe Shooter’ courtesy of team 2669 KY Bots, Kiryat Yam, Israel.

I don’t know about that, the only two mostly finished shooters I’ve seen (ours and pictures of 842) can knock the ball down (and catch it as it falls), scoop it up, and place it on the overpass, as well as hurdle.

I do think launchers though will be the high scoring bots of the regional. However, they may also receive more defense.

I agree…defense has me concerned!

The best strategy that I’ve come up with in my head (for an all out scorer robot) is a launcher. I think select few really amazing teams will realize that if you launch the ball with enough backspin and at the proper trajectory, it could bounce once and then land back in your robot as you drive under it. Do this consistently, and you could concieveably run 10 second laps with a hurdle every time around.

We have a shooter and I think that launchers will actually have less problems with defense. I stood 1.5 ft in front of our bot (I’m about 5’ 8") and the ball went clear over my head! So I know that we can arc over most little “pusher” bots. Launches can shoot on the run, while arms need to slow down a little and get in possition. With good aim, we they can every place the TB on the overpass at the end. Getting the ball off is a little harder though. Also launchers are far less top heavy. As for the back spin mentioned, 1726 is a perfect example.

Ok, well that was extremly bias, but heres my opinion.

The one potential downfall of a shooter bot is it’s heavy reliance on the state of the ball. These balls are going to be going through a pretty big beating on the field, and it’s likely that the inflation pressure isn’t going to be anywhere near a constant… i predict that a lot of shooter bots will have trouble with consistency between the matches - one ball might clear the rack when shot, but another might not be as inflated and fall short…

Actually, I would think that it would be the other way around. Our launch can shoot the ball no matter the same ( we even shot a '06 poof ball for fun:D ). While some gripper designs I have seen use wheels and clamps that would be affected by different ball psi.

Just so peolpe don’t think I’m stubern, I still expect to see some really good arms in compedtion.

That’s true, and the state of the game piece can also affect arm robots (as we learned last year with the varying inflation of the rings)

I think either an arm or a shooter robot can be very competitive, and each does have some downsides. We figured out how to make a shooter instead of an arm…so that’s what we did…kudos to those teams who make effective arms!

What about a launching arm?

It will be all about the speed that you can grab and then launch the ball.
I have seen some arms that can do that fast too.
We plan to raise our arm and the shoot the ball on the fly (cross your fingers.)

I think this will be a great game to watch with the different designs all doing the same thing all the while avoiding speed bots racing around the track and defensive bots hording balls and getting in the way of hurdlers.

Squirrel add 397 to your list we finished or robot last night and it has the ability to pick it up knock it down and when we shoot at an angle we can place it back on 80% of the time.
I agree that a launcher bot has a disadvantage with the consistency of the ball inflation. BUT if the launcher bot is good it will most likely be given the ball of its choice.
Squirrel be careful catching the ball as it falls is not considered scored. It needs to touch the ground or an opposing robot.
A student posted a picture a while back and we had it removed because we feel that a week 3 picture showing how we were shooting was a bit early.
We have a few pictures up on our website now and better ones to come in the upcoming week.
http://www.firstteam397.com/

Yes, that’s true…but I was talking about catching the ball immediately after knocking it down off the overpass in hybrid mode, not when hurdling, so catching it does not (as far as I can tell) affect the score in this case.

I agree that launching seems to be the most efficient way to do this. Also I think blocking a launch will be hard and can get ugly. I see no reason why a launcher can’t get balls down (with a simple extending post or whatever), back up at the end is another story (not that important in my opinion). I think many of us went the conventional route with the arm. Which can get the job done almost as good, but I’m thinking this is a launchers game. 2 or even 3 good launchers that have a good hybrid mode will totaly dominate. Offense will win the championship, defense against 3 offensive bots will lose consistently. So if you can get the attention off your good launcher, with another launcher, or even 2 of them you’re set. I don’t think these feeding strategies are going to work well. I think they’ll take too much time handing off the balls. So picking up well is just as important. Maybe a muscular ball grabber like 1902 and a couple launchers could put a good system together.

Launcher (118, our own design, etc)

  • From what I’ve seen this is faster
  • Less COG movement, less vulnerable to tipping
  • More complicated pick up and delivery system (I think we will see more 2 step processes to launch than to use an arm)
  • Can shoot from multiple positions on the field
  • Less vulnerable to “clothesline”
  • Can place ball on overpass if very careful

**Arm **(121, 179, 1902, etc)

  • From what I’ve seen, this is slower
  • Able to knock the ball off with little extra machinery
  • Can place ball on overpass easily
  • Moving COG may lead to tips or tough control spots
  • More complex software to manage joints and mechanisms

I think an efficient launcher that can “clip” the ball off the overpass and pass 2 lines in Hybrid mode will win most of their qualifying matches. From there an alliance of 2 launchers and a fast and powerful arm bot (defense) will be a good alliance, so long as the launchers are efficient at picking up the balls.

I agree with tom here. I think launchers are going to be the faster of the robots, not necessarily the “dominators”. I think teams getting their launchers in order is going to be a bigger task than many of them estimate. Arms have been done many a time in FIRST, not too many catapults have been built here before.

Two threads on this subject, the other one came first… so, this one’s locked. Go to the other one: