Robo-Cross B

[treeling]

What scores are you peoples getting?

[jander14indoor]

Not official forum, so not official answer, other opinions may differ, read the rules carefully yourself, if you want an official answer submit it through the FAQ process on the National webpage www.soinc.org, etc, etc...

If the rules don't say to tape the penny stack why would you expect them to be taped?

Jeff Anderson
Livonia, MI

[runslikeajohndeere]

Thanks for the chat...new to event and Science Olympiad. Showed team old bots we had. Homemade design pusher and homemade lift bucket were fun. Looking to upgrade. Any suggestions on where to find a gearbox to create effective lift and dump bucket?

[Toms_42]

Thanks for the chat...new to event and Science Olympiad. Showed team old bots we had. Homemade design pusher and homemade lift bucket were fun. Looking to upgrade. Any suggestions on where to find a gearbox to create effective lift and dump bucket?

Are you using a kit like vex/lego? I'm a little confused as to what you mean by creating effective lift to dump the bucket... If you are looking to lift the bucket vertically, you may want a belt for that, or an arm to take up less space.

For a belt lift, just do something like this:


If you want an arm lift without an elbow, you need a belt to keep the container level:


If you want an arm with an elbow, just use two servos. I don't know why you would need a gearbox, unless you are using ungeared dc motors. Most motors in kits are already geared way down.

For dumping, an elbow/wrist is helpful, just add another servo at the end to tilt the bucket. For the belt lift, running it all the way over will dump it. Keep in mind these are just a couple examples to try for a lift, you could also use linear slides, or carry the bucket itself so you don't have to lift or dump anything.

[dougleppard]

Update on our team.

Bot is built and have made several adjustments. Went a little crazy and used mecanum wheels which lets the bot go sideways as needed. The contest is hard. Knocking over both jugs takes time. I have told the kids to concentrate right now just getting the balls and legos first once they can do that in 3 minutes go for the pennies.

BTW the pennies are not taped, but can be picked up as a group, at least we have done it a few times.

Not much time left, only 5 weeks at this point.

I am dissapointed that there is only one run for contest, all that work for a 3 minute trial.

Doug

[jander14indoor]

Flipping jug up can be done quickly and relatively easily. Most teams I've seen do it just put a stick into it about half way and lift. Might take a little practice, but seemed to work pretty reliably. And the bonus you get on the high point items by having the jug upright in zone D is large enough to have a pretty significant impact on your scores and be worth some time. The way I read the bonus for splitting or sorting high value items it applies to all scorable items and is also worth some time.

Regards,
Jeff Anderson
Livonia, MI

[Toms_42]

Update on our team.

Bot is built and have made several adjustments. Went a little crazy and used mecanum wheels which lets the bot go sideways as needed. The contest is hard. Knocking over both jugs takes time. I have told the kids to concentrate right now just getting the balls and legos first once they can do that in 3 minutes go for the pennies.

BTW the pennies are not taped, but can be picked up as a group, at least we have done it a few times.

Not much time left, only 5 weeks at this point.

I am dissapointed that there is only one run for contest, all that work for a 3 minute trial.

Doug

We used meccanum's last year. Definitely a worthwhile choice. I wrote up some code to slow down diagonal movement at low speeds though, as meccanum's become VERY challenging to control at low speed. That and if you aren't using motor encoders, you should consider looking at this: http://www.vexforum.com/showthread.php?t=76943.
It's a matter of practice with meccanum's, my partner last year could barely grab anything when he started and a month of practicing later could clear the board in less than 1:30. Tell your driver(s) to just practice with them a lot, as they definitely can be a gamechanger. PM me if you are interested in the meccanum code I made, as making a good algorithm for the wheels is certainly helpful.

[runslikeajohndeere]

Thanks for the info. Kids compete in March, and we are in building phase. What position and where are the jugs in the competition?

[retired1]

Look at the diagram of the "field" in the rules.

[Trevor14]

I am planning on attempting Robo-Cross this year with my friend. I am new to the realm of robotics. We were talking about building it ourselves, no kit. Is that possible/affordable? Does anyone have any tips for getting started? Additionally, could someone tell me the approximate cost of supplies/tools I will need, where to get them etc.? Also would you need to program the robot? I know some code but I am not an expert so if you do, could someone explain? Thanks!