Kit of Parts Frame
 

Is your team going to use the KOP fram this year? If so why if not why not. Our team is split on the issue and im wondering what everyone else thinks.


Personaly i would rather have the satisfaction of building and designing the frame using the premade one just ruins alot of the fun.

Re: Kit of Parts Frame
 

not sure yet. the way i see it is that it is not worthy enough for the amount of competitions we will be going to. i see the amount of holes and light weight of it getting destroyed by the amount of ramming and hitting, as i calculated before you have around 3-5 "shoving" competitions during one match multiply that by 10 then by 3.5, since if int he elimination rounds you have to play every match unlike previous years.

my 2.01 cents, hope it helps!

Re: Kit of Parts Frame
 

Doesn't meet up to our specs, if we try and modify it, it probably would be more convenient if we just built an entirely new one.

Re: Kit of Parts Frame
 

We will probably use this one, with minimal customizations. Its better than what we've built before, so why not.

Re: Kit of Parts Frame
 

We're thinking of using it for the competition. It is VERY well designed and the cross sections/channel provides a good amount of stiffness, along with the relatively light weight. Some additional strengthening might be in order - our current thought is to replace the fasteners with welding after we finalize the configuration.

Re: Kit of Parts Frame
 

Has anyone weighed the frame yet?

Re: Kit of Parts Frame
 

FIRST lists it, and the two transmissions at 13.4 lbs

Re: Kit of Parts Frame
 

ya positively sure? i believe we weighed in around 9lbs for just one tranny

Re: Kit of Parts Frame
 

Documentation on IFI web site says 13.4 pounds (INCLUDING fasteners).

http://www.ifirobotics.com/kitbot.shtml

... but that DOES NOT include the transmissions.

Re: Kit of Parts Frame
 

My bad, I figured they included the transmissions in there... that's still pretty light though.

Re: Kit of Parts Frame
 

It simply does not offer the customization as other frame options such as 1010 and 1020 from 80/20. It also does not provide the rigidity that we need.

Re: Kit of Parts Frame
 

So have any of you preformed any tests on the frame to prove to your team that its not sturdy enough ? i can tell by looking at its going to get smashed up and bent, but our head mentor insists its "amazing" What other materials have teams been using? and how long does it usually take you to build a rolling chasis. (it took us 4 weeks last year because of lack of supplies and hes holding that over us.)

Again thanks for all your input

Re: Kit of Parts Frame
 

Some people might be jumping the gun on this framing. It really comes down to how you design your chassis. When you start making strong structural shapes with adequate support, (Just like you'd do with 80/20, box aluminum, pick your flavor) you'll see this holds up.

I don't have a piece of it in front of me, but it appears to be roughly an inch in size and U shaped. This means that you're having excellent structural design in terms of increasing your moment of inertia. When you look at how little material is at the edges of slotted extrusion, I think you'll find that this stuff will have a comparable (dare I even say better?) moment of inertia than your extrusion, and since they're both made out of aluminum, I'd say this will be just as strong, if not stronger than you 1010 80/20.

That's my 32 cents.

Matt

Re: Kit of Parts Frame
 

You are absolutely, 100% wrong.

I can tell you this frame went through EXTENSIVE destructive testing (vs. a concrete wall, among other things) and passed with flying colors.

When utilized correctly, it is more than adequate for the aggresive play of the FRC.

The only "weakness" is in torsional rigidity (cross corner twist). This can easily be eliminated through the design of an upper chassis (assuming you bother to mount a mechanism on it).


Don't believe me?
Play with it. It speaks for itself.

John

Re: Kit of Parts Frame
 

Our kitbot, with the chassis, motors, and trannies, weighed in at about 30 pounds.

Re: Kit of Parts Frame
 

Was this testing done with 120 pounds on the frame?

Also what is the material that the frame is made from?

Re: Kit of Parts Frame
 

Testing was done with 130 lbs on the frame.

Material is 5052 H34 Aluminum.
For more information refer to the documents found here::
http://www.ifirobotics.com/kitbot.shtml

Re: Kit of Parts Frame
 

That HAD to have been a lot of fun.

-Joel

Re: Kit of Parts Frame
 

Welding may be more complicated. As I read the specs for the frame material it is 5052 alloy of aluminum in the half hard state designated by the H34 designator. 5052 is weldable but tends to cracking on cooling. The aluminum once welded needs to be heat treated to relieve internal stresses induced by the weld and this is a complex process. If you have it welded by pros they will know what to do and should inform you of this.

You might look into some heavy duty aircraft style rivets as they can be quite strong, lighter than bolts and not subject to the complexity of welding this alloy.

I know there are probably teams out there that have welded frames in the past but it is usually 6061 alloy and not so subject to the cracking problem. Just a few thoughts and best wishes for the competition! LRU.

Re: Kit of Parts Frame
 

Wow, I want to comment anyone who spent atleast an hour making/designing these transmissions and frames.

If you get a chance to look at all the documentation on http://www.ifirobotics.com/kitbot.shtml
you will be suprised at the amount of work put into this project.

This will be great for rookies! :)

I think these will spur much more competition than normal!

Re: Kit of Parts Frame
 

Wow, some of you guys must do a lot of smash em up because I thought they may be a little over kill for a frame. We are using it to test the sensors and camera but as a frame for us it is just a little beefy. I do have to say that it is one of the most convenient items FIRST has released since the little plastic hubs for the skyway wheels. For rookie teams this is an incredible advantage to have a dual motor transmissions and a frame to put it on. When we were rookies it wouldn't have been a question whether we were going to use them or not.

Re: Kit of Parts Frame
 

AND Veterans Alike!

Re: Kit of Parts Frame
 

The kitbot provided really is the best thing that FIRST has given in the kit for a while. It is not only well designed, but easy to use. While the transmissions are large and by some evaluations heavy, they are well designed, robust, and very easy to use. I think many people are falling into the classic trap of pride when they dismiss using these components. As a poor team with limited machining facilities, these kit components are simply amazing. We are simply switching to different wheels in order to get better traction.

As far as robustness, the frame is quite tough. As long as you put some thought into how you mount other devices and components to it, it will be more than able to withstand the rigors of "appropriate robot interation". The hole pattern on all of the frame rails make it easy to customize and mount systems to. I think that many teams may end up designing their own frames that are just as strong and more heavy, as well as their own transmissions that provide simmilar reduction but have less efficiency or robustness.

Whatever components you decide to use or not use, you should put some real thought into the reasoning behind the decision. One of the most important things to making a good design decision is to have a rationale for making the decision. Many people depend far too much on intuition and pre judging designs rather than on calculations and testing.

I want to extend my thanks and congradualtions to Paul and John, the creators of the kitbot. You guys did a tremendous job. We might have our best drivetrain ever this year.

Good luck to everyone

Rob