7862Z Working Side-Roller Prototype (Reveal?)

FIRST THINGS FIRST: TAKE EVERYTHING YOU SEE IN THESE VIDEOS WITH A GRAIN OF SALT, THIS IS A PROTOTYPE AND NOT A FINAL, REFINED ROBOT. (also i suck at driving but that’s another topic entirely)

Videos:



I should also mention that for the Skills run, we were being limited to using red stuff only, and we had to score cones so that just made it way worse

Everything from here on down is comparing internals to internals, not these with externals for the sake of staying on topic and not straying to “external vs internal”.

Here’s a list of Pros and Cons of rollers in this fashion if done right, and a separate list of issues I personally have right now:

PROS

  • Fast, smooth Translation
  • Lighter Translation (ie. Compared to a Chainbar&Claw)
  • Simple to build
  • Simple to program
  • Multiple methods of intake and outake (ie. “The Passive Slam” and “Cone-Sucking”)
    CONS
  • Difficult to implement sensors with
  • Difficult to drive (Can be alleviated with practice, but not eliminated)
  • Doesn’t grant extra height as a part of translation (as opposed to chainbar/4bar on top)
  • Requires careful design of other mechanisms
  • Requires acute depth perception to accurately stack manually (though this could be eliminated through implementation of sensors and programming)
  • Roller Drift
    MY ISSUES
  • I drive worse than the people in the “Deja Vu” car montages
  • Lack of sensors
  • The rollers don’t go down far enough to consistently pick up cones outside of driver match loads, as the intaked mobile goal gets in the way
  • My spacing is SUUUPER tight, I had to gear my rollers down to high torque (6t sprockets, turbo motors) because I needed the room for internally stacked cones, though I still haven’t 100% fixed that as you see my bot descore a few cones here and there off of our stack by them catching at the back
  • Occasionally if a cone is improperly stacked it gets stuck on the bot and we can’t get it off
  • The current flip-out is super sketch and relies on tensioned rubber bands and two steel 1x2 bars to hold them in place
  • MY LIFT IS 20 LENGTH C-CHANNELS AAAAA TOO SMALL
  • I need more zipties to cover about 1/4 of the chain run rather than the like 1/7th that’s covered right now
  • My A+ wiring skills

So yeah, thoughts, comments, ideas, shoot. I’m all ears. If you think I said something wrong here, let me know but otherwise talk to you all in the following comment stream
IMG_3017.JPG
IMG_3016.JPG
IMG_3019.JPG
IMG_3020.JPG
IMG_3026.JPG
IMG_3027.JPG
IMG_3028.JPG
IMG_3029.JPG

Nice! I’ve seen that design from a couple teams but this is the first I’ve seen it work, it looks good for a prototype. We almost built something like that on the top of our scissor lift but we liked the the fact that using a four bar allowed is to stack three cones without using the scissor lift so we ended up scrapping the idea. I’d love to see more of this, best of luck!

Yeah, same. I’ve seen it work at a passable level, but I’ve yet to see another roller robot that covers as many of the issues they can have as well as this implementation did, but I still acknowledge that it could work way better with more work. A small disadvantage like you said is that rollers don’t gain you extra height, but I think it’s a trade-off between [Greater-Height] and [Faster-Translation] . Thanks for the compliment, by the way.

Great idea!
I was wondering if your problem of descoring cones would be solved if you made the back of your rollers wider than in the front. By doing this you can go around the stack and still be able to pick up cones at the front

You guys did well with this prototype so far, but this mostly just convinces me that side rollers won’t be better than 4-bars or chain bars for stacking. Maybe as good as, but not better.

This is only tangentially related, but I am so jealous of that robotics room! Two fields! More than 2 feet around the field to walk around! Doggo!

I am also SUPER jealous of the robotics room! Lol we only have room for half a field, sandwiched in between storage shelves in the back of our school’s engineering room. We have .125" clearance around the half field on all sides except one (where we get 2’ of clearance)

Yeah, that is a really nice room. We have half of a classroom for 6 teams and when we want to practice driving we have to set up the field in the hallway and take it down at the end of practice :stuck_out_tongue:

/ / / / /

Yeah, we got our second field second semester last school year! it’s pretty hype, but the reason we have so much space is because that’s the old A/V room we commandeered and conjoined with the woodshop room which is the one in the background of the skills run. 7862 currently has over 16 teams (mostly of 2 people, we have one 3 person and two 1 person teams. also it could be as many as 22 but i forget) so we actually really needed the extra field.
And yeah Stella (doggo) is a bit of a celebrity around 7862, she’s really nice (last year’s bots scared her, though…)

I just have 1 suggestion I know you already mentioned it but ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES ZIPTIES the base looks like the spaghetti I had for lunch last week :slight_smile: I am glad to see a different type of intake and a different though process. Couple people mentioned it but I wish our school had a Vex lab like that.

7862Ziptie

Mind Blown

:slight_smile: