24C 2.0 "The Vacuum" Build Reveal

[ifticar2]

Great robot, but I would suggest covering the conveyor belt with anti-slip mat since sacks tend to slide down on the regular plastic treads.

[LegoMindstormsmaniac]

@ifticar2

Great robot, but I would suggest covering the conveyor belt with anti-slip mat since sacks tend to slide down on the regular plastic treads.

Yes, you are correct. I think I failed to mention that we were planning on most likely putting a bunch of the high traction tread links on the conveyor, to add some grip.

Thanks for the post!

~Jordan

[DracoTheDragon]

We’re hoping to hold nearly 20 sacks at once, but the robot will not have to drive very far to score them, and it will collect that many almost instantly, without having to move around while getting them.

Also, we determined that since last year we had a 2:5 ratio with small wheels last year, which was powered by four 3-wire motors and two 393 motors. It was very reliable and never had issues, even when we got into pushing matches. Now VEX has posted specs that say the 393 motors have more than two times the torque of the 3-wire motors, but if they were only double, we would have 1.5 times the torque we had last year. Going from 1:2.5 to 1:3 will only be 1.166667 times the speed we had last year. Looking at those kind of numbers, it’s pretty obvious that we should be okay with a 1:3 ratio this year.

where’s that not bad meme. . .
i don’t think i could of made a better robot for this type of strategy:)

[john01]

Would it be possible to see a video of this robot? I am very curious to see how this intake picks up and descores sacks, as well as how helpful the tank tread conveyor belt is.

[mbrunn]

well thats probably the best idea ive seen this year. simple. efficient. cleanly built. good job!

[LegoMindstormsmaniac]

@DracoTheDragon

where’s that not bad meme. . .
i don’t think i could of made a better robot for this type of strategy:)

@mbrunn

well thats probably the best idea ive seen this year. simple. efficient. cleanly built. good job!

Thank you both so much! I hope that us posting this here may help “Spark” (;)) some ideas for some other teams.

@john01

Would it be possible to see a video of this robot? I am very curious to see how this intake picks up and descores sacks, as well as how helpful the tank tread conveyor belt is.

Okay, update on the robot. Monday night, unfortunately not a whole lot physically was done on the robot. Mostly it was “hidden” stuff. For example, there were two tabs of metal which we knew were going to have to be cut off the drive so that the conveyor’s tread didn’t hit them. We also had to add support to the 4-bar mounts, so that the weight of the intake didn’t cause them to bend forward. We also added rubber links to the conveyor, although after testing it for a minute or two yesterday, I think we may need some more (we were running low, but I think 24A has found a way to use fewer than they had been… ;)), and then finally we simply added a limit for the top-roller so it would be kept at the correct height.

Still no video, guys. Sorry. I’ll try to get some as soon as I get a chance to try it out again.

~Jordan

[ClockWorkKnights]

eagerly waiting to see this beast in action.

[LegoMindstormsmaniac]

Videos at last!

Intake 8, 1 at a time
Intake Pile of 5 & 8
Intake Pushing Sacks Out

Sorry that they aren’t very good quality, and don’t show very much.

Anyway, enjoy!

~Jordan

[JesseCRN]

Looks like your intake works pretty good.

Why did you use the standoffs? Did Tank Tread not work?

Have you had any tipping problems? It looks like you intake/hopper would be VERY heavy.

[banditofernando]

@Jesse323Z

Looks like your intake works pretty good.

Why did you use the standoffs? Did Tank Tread not work?

Have you had any tipping problems? It looks like you intake/hopper would be VERY heavy.

The stand offs (I’m pretty sure this is why he used them, its why our team used them too) prevent the flaps from bending back, so when intaking they are almost straight out like Wheel legs, but they don’t have as much of a chance of throwing the sacks out of the robot.
(Sorry for answering jordan >.<)

[JesseCRN]

@banditofernando

The stand offs (I’m pretty sure this is why he used them, its why our team used them too) prevent the flaps from bending back, so when intaking they are almost straight out like Wheel legs, but they don’t have as much of a chance of throwing the sacks out of the robot.
(Sorry for answering jordan >.<)

Hmm… OK. They would be to heavy for our bot… We only have the short flaps on our intake, so it wouldn’t help that much.

[LegoMindstormsmaniac]

@banditofernando

@Jesse323Z

Looks like your intake works pretty good.

Why did you use the standoffs? Did Tank Tread not work?

Have you had any tipping problems? It looks like you intake/hopper would be VERY heavy.

The stand offs (I’m pretty sure this is why he used them, its why our team used them too) prevent the flaps from bending back, so when intaking they are almost straight out like Wheel legs, but they don’t have as much of a chance of throwing the sacks out of the robot.
(Sorry for answering jordan >.<)

Thanks! And that’s perfectly okay; thank you for answering!

Yes, we used the standoffs to add some rigidity to the intake. The flaps were a bit too flexible.

Also, we haven’t wired everything up yet, so we can’t really test driving it around. We’re hoping to have most of the team over here at my house this Saturday, so hopefully we’ll have it wired up and driving around by the end of the day! More videos out once we get that far.

~Jordan

[934B]

@LegoMindstormsmaniac

We’re hoping to hold nearly 20 sacks at once, but the robot will not have to drive very far to score them, and it will collect that many almost instantly, without having to move around while getting them.

Also, we determined that since last year we had a 2:5 ratio with small wheels last year, which was powered by four 3-wire motors and two 393 motors. It was very reliable and never had issues, even when we got into pushing matches. Now VEX has posted specs that say the 393 motors have more than two times the torque of the 3-wire motors, but if they were only double, we would have 1.5 times the torque we had last year. Going from 1:2.5 to 1:3 will only be 1.166667 times the speed we had last year. Looking at those kind of numbers, it’s pretty obvious that we should be okay with a 1:3 ratio this year.

Unfortunately, no. That tournament is not on our schedule. We are planning to be at the PA State Championship again this year, but that isn’t going to be for months.

Thank you!

~Jordan

you should definitely be able to move 20 sacks with a 1:3 ratio our robot at towson has a 1:1 gearing ratio with 4 inch wheels and we can move 24+ sacks on a field with 2 269s, and 2 393s geared to 6 wheels the only problem i can see is lack of ground contact causing to much friction on 4 tiny wheels

[934B]

also it might work on a floor or a table but once you test it on the mat materials it might not work we had a robot that was flawless until it hit the mat

[X-Factor]

@934B

also it might work on a floor or a table but once you test it on the mat materials it might not work we had a robot that was flawless until it hit the mat

Yes this happened to us, I would suggest maybe adding a couple more free spinning wheels to give better support.

[ClockWorkKnights]

I can’t wait to see video of this design in action.

[Warrior5]

@LegoMindstormsmaniac

24C was planning on attending the HZR September Scrimmage this past Thursday, and afterwards we were planning on revealing our new robot design. However, that event was canceled. But we decided to reveal our new design anyway. So, here it is. Enjoy!

After the REX tournament, we decided to modify our robot to be a design similar to what 24A had built. The concept was to have an intake with a wide vertical wheel roller (no longer the “chainsaw” type of intake we used on the first robot), to pull the sacks in from above, and have a bed of tank-tread running the opposite way underneath, to help pull them in. The tank-tread would keep the sacks from collecting at the front of the intake while we were picking them up, preventing the “in, up, over, and out” problem with vertical wheel roller intakes.

Now, this was not the only change we made to our robot. In fact, since the REX tournament, 95% of the robot has been completely rebuilt. The drive is brand new, which is now using four 2.75" omni-directional wheels, at a 1:3 gear ratio (still using six 393 motors). We were able to use each of the 4-bar systems we had on our old robot, but they were moved much further apart, and still had to be modified.

Okay! Now for pictures! (Probably the only thing many of you want to see, anyway. :P) Click them to see full-size.

This Monday night, we are hoping to finish up the robot, so we can begin programming, and test-driving. If I can get a video of it, I will try to post one as soon as possible.

We hope that you like our reveal, and would like to thank you for viewing it! If you have any questions about our new robot design, please feel free to ask; I will try my best to answer.

~Jordan

Hmm, I think I know the answer, but how is the long tank tread in the hopper powered? It looks like it would have to be the two motors up in the front but I couldn’t tell for sure…

[JesseCRN]

@Warrior5

Hmm, I think I know the answer, but how is the long tank tread in the hopper powered? It looks like it would have to be the two motors up in the front but I couldn’t tell for sure…

The answer to what?

[tabor473]

His own question about how the tread is powered.

[JesseCRN]

@tabor473

His own question about how the tread is powered.

Oh, I see

Thanks!