Pitching Style Or Catapult???
 

Which one is your team using?

Josh

Re: Pitching Style Or Catapult???
 

We found that a pitching machine would be much faster than a catapult. Plus it is easier to do unless you’re doing a one shot deal and it’s done.

Re: Pitching Style Or Catapult???
 

We prototyped both types and were actually leaning toward a double actuated catapult design, but because of a rule clarification we had to scrap it due to size restraints. We are now using a one wheel shooter that is on a turret and can change the angle that the ball will come out.

Re: Pitching Style Or Catapult???
 

Sorry, I can't answer the poll until after the robot is shipped due to confidentiality agreements.

I recall four distinct proposals made by the first-week design subgroups. Two were for a straightforward one-wheel pitcher. One was a catapult. One was a monster spinning cylinder that could fling multiple balls at once. Of the prototypes, the catapult's aim was the most repeatable, but it was also the slowest by far, and there was no obvious mechanism for reloading it. Though there were no working pitcher prototypes, a softball-shooter derivative seemed the easiest to implement. When it came time to decide what we were going to build, even the person who designed the catapult mechanism voted against it. :cool:

(Note that I have fulfilled my commitment to secrecy, and haven't actually revealed what we ended up choosing.)

Re: Pitching Style Or Catapult???
 

Well by the sounds of it we might have one of the only catapult designs. I can't speak for it's accuracy as it is not assembled yet, but we had 90% accuracy on the prototype made out of spare conduit and bike parts :cool: .

The latest picture we have (rather outdated - now robot is painted black and has wheels on) be seen at: http://marsbot.org/gallery/?g2_itemId=3069

Our inventor renderings (being completed as we build the bot :yikes: ): http://marsbot.org/files/images/bot_iso.gif

Hope you think it's decent! We will post a video of the speed of the throwing arm soon but let me assure you its impressive!

Re: Pitching Style Or Catapult???
 

about how fast can you shoot? In terms of balls per second?

Josh

Re: Pitching Style Or Catapult???
 

It isn't assembled yet so I can't tell you the true speed. We had the motor mounted on briefly to make sure everything was working (turns out it wasn't: shaft wasn't hardened and it did damage to it in just a few minutes [our new hardend shaft arrived today :)]).

Heres a link to the video I took (MP4): http://marsbot.org/files/arm_demo.zip

EDIT: All though it is mentioned in the video if you listen closely, the medical tubing we are using is weak compared to what we are expecting to use.

Also, if anyone knows of a good MP4 to WMV converter I would love to have it :p . Feel free to pm me if you know of a good one; thanks!

Re: Pitching Style Or Catapult???
 

What are you planning on using?

Josh

Re: Pitching Style Or Catapult???
 

We're going with a launcher wheel, but one idea that came up AFTER we'd finalized the design was the posibility of using a paddlewheel style launcher (Drop a ball on a paddle, spin it around, ZING!) it would've been interesting, but not very easy to load and probably prone to jamming

Re: Pitching Style Or Catapult???
 

Plan on using? What do you mean by that? We are going with the repeatable/revolving catapult design (no time to do anything else even if we wanted to!). If you are asking about the motors I have no idea. I work on the team's website (http://marsbot.org) and am currently working on the hopper but I try not too touch too much of the core stuff in fear of breaking it ;)

Re: Pitching Style Or Catapult???
 

we have a pneumatic shooter that shoots just under 1 ball/sec (limited by loader) with repeatability of a few inches.

Re: Pitching Style Or Catapult???
 

do you have any pics of it?

josh

Re: Pitching Style Or Catapult???
 

We have a pitcher type shooter its fairly accurate and fairly fast, i think that most teams will be using the pitcher type of shooter, but mars did a very good job designing that catapult type of shooter, There bot looks very well designed cant wait to see it at UCF.

Re: Pitching Style Or Catapult???
 

:yikes: Hey im with M.A.R.S 2 with robosapien
We just got our bot done and actually it is amazing.
the ball speed is about 25 miles per hour and about a ball a second. From what weve heard we will keep up with the cannons and pitching machines.
We all were amazed at how it worked. I admit i had my doubts but man has my mind changed. C u at nationals and at FL regionals.

Re: Pitching Style Or Catapult???
 

However, almost everyone else on the team voted for it, so that's what we designed and built. :)

Re: Pitching Style Or Catapult???
 

Your a sly man Mr. Anderson...a sly man... ;)

Re: Pitching Style Or Catapult???
 

We have a pitching machine that i slifted by a catapult-like mechanism.

Re: Pitching Style Or Catapult???
 

Pitching style, mainly because we could easily convert it to a hand held version to use in our dodgeball games.

What? It seemed like a good idea at the time.

Re: Pitching Style Or Catapult???
 

Three wheels driven pitcher. Testing showed very consistent shooting, final assembly and wiring still to be completed.

Re: Pitching Style Or Catapult???
 

We chose to forego the idea of a throwing mechanism for an extremely tough drive train. The only way our robot expels balls is by the reel that loads the hopper, when it is reversed to unload.

Re: Pitching Style Or Catapult???
 

Our team is using a pitching style unit with a guide system.

Re: Pitching Style Or Catapult???
 

our engineer prototyped a sling sot mechanism that would have shot 2 balls at a time and it was actually not that bad but the students came up with another style and prototyped it and made a believer out of him so we kind of are like a pitching mechanism in some ways but really can't explain what it really is. it is more like gravity/pitching all together

Re: Pitching Style Or Catapult???
 

We use a pitching-style shooter.
The only thing is that it seems to generate a lot of static electricity. Then you can tell the freshman kid to touch it and he gets shocked.

No but seriously, does anyone else experience this type of static?

Re: Pitching Style Or Catapult???
 

Hmm, I would like to ask how much does a guiding mechanism (aka, barrel or something similar) help the aim of your robot? When we were practicing with our prototype, we determined that such a guide would slow down our muzzle velocity and the precision of the mechanism did not change to any significant degree. So, we did not include any barrel into our final design as was originally planned. So how was your team's experience with aiming mechanisms?

Re: Pitching Style Or Catapult???
 

My teamnever even gave the catapult style a thought...we instantly went with the pitching style