Chief Delphi - Angled Bumpers

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Re: Angled Bumpers, concave design

Quote:

Originally Posted by jjb.bailey (Post 1635937)

We at Team TNT2404 think we can use a concave design. Please check our image link above. It's a quick drawing to show "the maw"; we will have bumpers around perimeter as required. See Figure 8-1 in the 2017 Manual and description of Example following R01. Based on those figures and examples, we would like to know which rule the attached "concave" design might be breaking.

jjb.bailey
Mentor-rookie year
Parent-third year

Definitely not legal. You're not defining your frame perimeter properly. See R01. Take your frame, wrap a string around it, and that's the frame perimeter. I've taken the image you posted and drawn the frame perimeter in red, and the necessary bumpers in front in green.

http://i.imgur.com/8HqBrGM.png

Re: Angled Bumpers, concave design

Quote:

Originally Posted by jjb.bailey (Post 1635937)

link

We at Team TNT2404 think we can use a concave design. Please check our image link above. It's a quick drawing to show "the maw"; we will have bumpers around perimeter as required. See Figure 8-1 in the 2017 Manual and description of Example following R01. Based on those figures and examples, we would like to know which rule the attached "concave" design might be breaking.

jjb.bailey
Mentor-rookie year
Parent-third year

It took a bit of work to find the link, but the word link above links to what I think you're interested in. I'm not completely sure what I'm supposed to be looking at, but trying to figure it out, this is my best guess:

The blue polygon is your chassis frame, and the grey rectangles are segments of bumpers.

If this is the case, your design is right out. The FRAME PERIMETER is the smallest CONVEX polygon which includes all of your robot, excluding bumpers and bolt heads. In your case, the FRAME PERIMETER is a rectangle which includes all of your "maw". This rectangle is the one which requires 6" of bumper support at each corner. Most of the grey rectangles are inside the FRAME PERIMETER, and are not BUMPERS.

Re: Angled Bumpers

Just a word of caution:

I happen to know that a fair number of inspectors and Lead Robot Inspectors are on CD. Posting designs that have previously been posted and identified as not being legal may invite extra scrutiny at events.

Something like the proposed design might even get you an early inspection--at least long enough for the random passing inspector who happens to spot it to point you in the right direction to make the necessary changes before pits close on the first day!

Re: Angled Bumpers

Solution to avoid all of this: use an intake that extends beyond your frame perimeter and has mecanum wheels or some other way to center balls that are being pulled in. I don't know your whole robot design, obs, but just removing those awkward angles (which definitely aren't going to be 6 inches, and then you need another 6 inches on either side of the gap in the center there) and using a flat front for your robot with a flip out intake, you could fix this whole problem easily.

Re: Angled Bumpers

Quote:

Originally Posted by pmattin5459 (Post 1636157)

Solution to avoid all of this: use an intake that extends beyond your frame perimeter and has mecanum wheels or some other way to center balls that are being pulled in.

...and give up 3 to 4" of hopper size because you have to pull the frame perimeter back to fit in the maximum volume. That is, unless you do an expanding hopper design like Big Bad Bob, but now you have a pretty critical part of the robot sticking out that you can't retract away from a collision - so it's a foul and damage risk.

Re: Angled Bumpers

As a general rule of thumb, I'd like to summarize a few points.

If you place your robot in the smallest box possible that it can fit in, and the box has NO concave faces, that box is your frame perimeter. Your bumpers MUST be around that box (the frame perimeter), NOT your robot frame. This is explicitly defined in the game manual and has been a rule for as long as I can remember. do NOT have any concave bumpers, as you will not pass inspection and will need to do major modifications to pass.