Pitching Style Or Catapult???

[sgsdragons]

Which one is your team using?

Josh

[DjAlamose]

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.

[KuhnDog]

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.

[Alan Anderson]

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.

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

[Tim Arnold]

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 .

The latest picture we have (rather outdated - now robot is painted black and has wheels on) be seen at: http://marsbot.org/gallery/?g2_itemId=3069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

[sgsdragons]

Originally Posted by robosapien

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 .

The latest picture we have (rather outdated - now robot is painted black and has wheels on) be seen at: http://marsbot.org/gallery/?g2_itemId=3069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

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

Josh

[Tim Arnold]

Originally Posted by sgsdragons

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

Josh

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 . Feel free to pm me if you know of a good one; thanks!

[sgsdragons]

Originally Posted by robosapien

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 . Feel free to pm me if you know of a good one; thanks!

What are you planning on using?

Josh

[Nuttyman54]

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

[Tim Arnold]

Originally Posted by sgsdragons

What are you planning on using?

Josh

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

[Rickertsen2]

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

[sgsdragons]

Originally Posted by Rickertsen2

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

do you have any pics of it?

josh

[CaseyKasem_1251]

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.

[MarsBOtkid]

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.

[Alan Anderson]

Originally Posted by Alan Anderson

When it came time to decide what we were going to build, even the person who designed the catapult mechanism voted against it.

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