Bumper Rule
 

Do the bumpers have to surround the frame/base of the robot completly, or can there be a gap? My team has looked at the rules, and everyone interprets it slightly differently. Anyone know??

Re: Bumper Rule
 

It has to cover 2/3, so you can have one side un-bumpered.

Re: Bumper Rule
 

this is a good question as we were wondering the same thing.
perhaps others can provide more insight.
Where is the 2/3 rule?

thanks

Re: Bumper Rule
 

There was another thread on it that actually called out the exact rule, I'm going to bed pretty soon here so I won't look it up but I do remember reading it earlier today.

Re: Bumper Rule
 

there u go!

Re: Bumper Rule
 

why so early? its only 9:15pm....

















Hawaii time.:D :D

Re: Bumper Rule
 

Because I'm in California. =p

Re: Bumper Rule
 

So basically, to be safe, 3 sides of your robot... assuming its a rectangular robot. :rolleyes:

Re: Bumper Rule
 

Another question and answer on bumpers just for clarification.

Rules say that bumpers need to 2 1/2 inches from floor and 5" tall. What if I do not want a chassis that is 7 1/2" tall from the chassis? I'm assuming that I can have the bumpers above the chassis walls/sides if I want. Is this correct?

I may have to go to Q&A on FIRST.

Re: Bumper Rule
 

That would be correct. As long as the bumpers are in the bumper-zone space, you can put your chassis and effectors wherever you please.
I think the reasoning behind the super-defined bumper zone is to keep all contact at the same level and create a "safe zone" for the more fragile components such as manipulators.

Re: Bumper Rule
 

This was the general rule last year. As long as you have 3 sides covered, you wont have any issues with the judges.

Re: Bumper Rule
 

There was no rule in place last year requiring teams to have bumpers.

Re: Bumper Rule
 

To answer your original question - yes, there can be gaps as long as you cover 2/3 of the perimeter, and no bumper segment can be less than 6" long.

Re: Bumper Rule
 

With a give maximum sized robot of 38" x 28" giving us:
((38*2) + (28*2)) = 132" perimeter

2/3 of 132" = 88"

Technically I guess you can only cover 88" worth of sides if you wanted to.

Some people tend to cover just 3 sides of their robots so using the 2 most basic configurations of robot design...

1) 38+38+28 = 104" of Bumper (38" Sides & 28" Rear)

or

2) 28+28+38 = 94" of Bumper (28" Sides & 38" Rear)

In configuration 1, you are good.

In configuration 2, you are good as well.

Re: Bumper Rule
 

Specifically, the rule states that a STANDARD bumper as defined in Fig. 8-1 must be no shorter than 6 inches. Since they also do not want "hard" bumpers in the corners, you must place a vertical pool noodle to soften the corners of the side or front bumpers such that it covers the corner.

The extra vertical pool noodle that isn't part of the STANDARD bumper cannot count toward the minimum 6 inches. Though it is unfortunate, this is the only interpretation of this rule I can come up with.

Re: Bumper Rule
 

Hey Elgin, try doing that math again on #2.

Re: Bumper Rule
 

Oops.. bad typo! LOL Thanks, I'll go back and edit that.

Re: Bumper Rule
 

Can you quote the rule stating that you "must" use a vertical pool noodle on the corners? I've looked and can't seem to find it anywhere...

Re: Bumper Rule
 

There is nothing requiring that a vertical pool noodle be used in the corner, but because the only thing that can be used in the corner is a pool noodle or cloth piece of bumper (and not wood, or other "hard" materials), most teams cut a pool noodle the height of a bumper and stand it up in the corner.

Figure 8-2 on page 10 of THE ROBOT shows exactly the scenario I am describing in the top left corner of the view of the robot on the left.

And lower left on the image....
Basically what this is saying is that you can not "miter joint" the wood going around your robot behind your bumpers.

I'll try and get a good picture of what we have done and has been accepted in the past with these rules (which have not changed much, if any over the years of bumpers - other than the REQUIREMENT to have them this year as opposed to previous years.

Re: Bumper Rule
 

Fixed your post.

The note in Figure 8.2 says, "if needed, a pool noodle corner can be wrapped into bumpers - bou only pool noodle and cloth may penetrate the corner space"

Re: Bumper Rule
 

Yea my bad. The point of the post was to clarify that the vertical pool noodle isn't part of a standard bumper by definition, therefore the vertical pool noodle should not be used in the 6" minimum dimension. I've thought about this several times due to the fact that our team this year is going with an open-front design and due to the nature of the bumper rules we unfortunately cannot have bumpers on the front, at all.

Re: Bumper Rule
 

Heres a quick question:

What if one were to put bumpers on their robot in such a way that they fit all regulations and made contact within the bumper zone, but also extended below the 2.5" mark??

Re: Bumper Rule
 

If it was below 2.5" it would not fit regulations.

Re: Bumper Rule
 

Here is something to keep in mind for mounting bumpers in general, but especially on shorter bots:

Make sure that your standard bumpers can simply and securely attach to your chassis in the bumper zone with reasonably sized fasteners. Incorporate the bumpers into your design, don't wait till the last minute to to find a way to attach them.

As an inspector last year, I saw 1 or 2 teams that needed some sort of metal bracket to fit the bumpers in the right place vertically. The teams thought these brackets would be counted in the weight of the bumper, but the brackets are part of the chassis and counted against the weight (and size) of the robot. Many other teams simply mounted the bumpers several inches outside of the bumper zone (between 2.5" and 8.5") because that was where it fit easily on their chassis.

With bumper requirement this year many teams will be building them for the first time. Don't make bumpers an afterthought because unlike last year you can't just take them off if they don't meet requirements.

Re: Bumper Rule
 

Our design calls for bumpers around the entire perimeter of a rectangular shaped robot and our design is such that the bumpers could be constructed (fastened together) as a single assembly with with either an overlap of the plywood in the corners and/or an angle bracket behind the plywood in the corners. If we did an overlap of the plywood in the corners would be be violating the no hard part of the bumpers may extend into the corners rule? If we rounded the outside corner of the plywood overlap so that no hard part of the bumper extends more than one inch beyond the robot frame would we be violating the rule? If we left the plywood completely out of the corners and fastened the segments together with an L bracket from behind would we be violating the rule?