pic: 1885 Drive Train 2010

[Travis Hoffman]

Originally Posted by hipsterjr

My, that frame looks familar

Indeed....

[Valkyries_698]

we are doing something similar but with a slick wheel at the front,

We have been researching a system called Rocker-bogie

[fordchrist675]

I think you should ship the robot as is! I am sold on the wood chassis haha!

Looks like a ingenious idea.

[hyperdude]

Originally Posted by Valkyries_698

we are doing something similar but with a slick wheel at the front,

We have been researching a system called Rocker-bogie

Mars rovers, right? Funny thing, I came up with something almost exactly the same (prototype design).

Originally Posted by hyperdude

Mars rovers, right? Funny thing, I came up with something almost exactly the same (prototype design).

Tanks have been using a Rocker Bogie system since long before the rovers. Go take a look at the old Shermans, those are neat pieces of rolling coffins!

[Valkyries_698]

Originally Posted by CraigHickman

Tanks have been using a Rocker Bogie system since long before the rovers. Go take a look at the old Shermans, those are neat pieces of rolling coffins!

well this rocker-bogie was worked on by someone that is on the game design team

[Raul]

I believe the main advantage to articulating the wheel pods is to maintain a more level chassis while going over the bump.

Look at the wooden model in the picture Jason provided. If the rear wheel pods are articulated (rotated) so that only the rear-most wheels are touching, the angle of the main frame will be at a lesser incline and provide a greater safety factor to prevent the center of mass from getting close to the tipping point.

[JesseK]

Originally Posted by Raul

I believe the main advantage to articulating the wheel pods is to maintain a more level chassis while going over the bump.

Look at the wooden model in the picture Jason provided. If the rear wheel pods are articulated (rotated) so that only the rear-most wheels are touching, the angle of the main frame will be at a lesser incline and provide a greater safety factor to prevent the center of mass from getting close to the tipping point.

Interesting point, especially considering that the bumper zone rules aren't as strict while on the bump. Our primary goal with the conforming articulation (not sure what to specifically call it) was simply to maintain a controlled climb, peak, and descent. Doing so, we believe, will reduce the risk of tipping over. If anything, the heightened clearance requirements of this natural articulation may elevate the c.g., yet we are doing some very careful calculations (one of the mentors understands them ... I don't, heh...) to ensure we're under the tipping threshold.

For those interested, the actual drive train weighs in at 45lbs. Yet that's also with a subframe capable of withstanding some pretty high stresses due to high tension. We feel the extra weight is a good trade-off for stability & reliability.

[waghalter]

jesseK is right,

as the student leader of the design team building this, along with our mentor's help, we found that the pivot has some extremely strong forces acting on it. the potential for the pivot axel to get bent or damaged is high if the robot's design does not build in enough support to stiffin the axel.

so please consider this if you are doing a similar design. best wishes team 698. Good luck !

[Daniel_LaFleur]

Originally Posted by Tom Line

A word of caution. If, during a pushing match etc, the torque of your wheels causes them to rotate the assembly and lift your bot up an inch or two, your bumpers will be out of the legal zone. This may be deemed illegal and you may be DSQ'd (if someone decides to protest). You may want to look at some sort of active actuation to prevent it.

Incorrect. The bumperzone is defined with your wheels touching the ground.

If you are pushed in such a way that your wheels are not touching the ground (like being pushed up a ramp) then the bumperzone no longer applies.

If it were as you stated, then any time a robot went over the bump they would gather a penalty.