There was quite a bit of discussion a few weeks ago about what kind of traction KOP wheels would have on ‘diamond plate’. We drove a robot on our ramp this past week and here’s the video http://www.youtube.com/watch?v=qyTBvyRluOs. As you can see from the video there is more than adequate traction to slowly drive a robot up our 20 deg ramp. Since traction is coefficient of friction times normal force, robot weight is not a factor, that is if you’ve got enough power to do it in the first place. Btw, the ramp robot is a rookie team’s that our team is mentoring
Is that This years Bot
And center of mass has no real bearing on traction either, unless the center of mass is arranged such that no real downward force is put on the wheels… but if that is true, you have other things to be worrying about right now.
I guess I just don’t see what you were tying to say…
That is the robot of rookie team 2250, Lancerbotics, here in Denver. They came up with a unique design. Their concept is to be a lite robot ( it currently weighs about 30 LBS) that can drive up any ramp. Being lite they are optimistic some robot may be able to lift them with their arms. Being small their game strategy is to just drive around and get in the opposing alliances way. It looks a lot like a kitchen sink and is made out of 7075 aircraft aluminum.
Thanks for the plug for our Bot. We are almost finished having just the wiring and the lid to complete. We will have pictures posted soon of our bot in its completed formation. Good luck to everyone and don’t be afraid to pick-up the kitchen sink AKA “MINI-ME” 
Err… normal force is the robot’s weight. Weight has everything to do with force of friction, but, if you mean that weight has no bearing on the ability of a robot to get up a ramp, you’d be correct. Force of friction decreases linearly with weight, but so does force required to move you up the ramp.
Nice job though guys. Any issues regarding robots falling off the sides, with no guards? A bit of excitement during the matches can mean a dropped robot for teams sometimes.
They should strap an inner-tube shaped construct onto their robot so that grippers have a better chance at being able to lift them.
How much clearance does a robot need to make it over the corner of your ramp onto the platform?
That robot has 2 1/2 inches of ground clearance on a 27 inch wheelbase. They’re working on a lift fixture to try at our regional scrimage this coming weekend. Is any team thinking of trying to lift another robot with their arm?
We are in the process of installing a lift ring so that we can be lifted by robots that have a lifting arm. We should be light enough that any arm can lift us. we are guessing less than 50 pounds.
Umm… how much 7075 does this robot have?
That’s still a hefty weight for most arms. Considering a game object weighs only about 1 lb. this year, most arms arn’t going to be designed to lift 50.
i would recommend that you put a stop on the far side of the ramp, as many robot may fall off the edge if they go too far
The complete tub was formed out of .050 7075 t-6 in 5 pieces with .750 Radius at the bends and it is very light assambly. The material could not be formed by conventinal process due to fracturing. We used a modified DOM process to reach the 90 deg angles without cracking.
During the testing and in the video clip http://www.youtube.com/watch?v=qyTBvyRluOs we only had 2 drivers go over the edge none of them went off they just droped the wheels over the side. How ever we are going to install a angle to act as a wheel chalk to prevent over runs on the ramp it may not stop a robot at full throttle but should let the driver know there at the end of the ramp…