How can we drive on this new floor?

[Zyck_titan]

Originally Posted by thefro526

That's an easy assumption to make.

But what about momentum? Changing directions with a heavier bot it's going be be a bit harder I think... Or maybe not, I'd like to get some input on this.

Well what if you could control how much you wanted, you know actively change from a heavier bot to a lighter bot in the middle of a match, you could start moving by being light, "make" yourself heavy if you don't want to be pushed etc.

I do have an idea for this, but I'm trying to stimulate the thinktank, see what else people come up with

[gorrilla]

car steering might make a comeback this year......seeing as how tank drive wouldent turnas well,(drifting around with the trailer would take some getting use to though)

[dmlawrence]

In theory, one could construct giant omniwheels using each Rover Wheel as one of the horizontal rollers...

<R06>
...The ROVER WHEELS must be used in a “normal” orientation (i.e. with the tread of the wheel in contact with the ground, with the axis of rotation parallel to the ground and penetrating the wheel hub)...

Originally posted by Branden Ghena

I think...R06 might disallow that, along with the general logistics of building giant omniwheels.

I believe R06 would only apply to the wheels being "used" - that is, the ones touching the ground. The configuration would then be legal, since the wheels not satisfying R06 would not be in use.

Such an omniwheel would have nearly triple the traction of a single Rover Wheel.

[Mike8519]

Originally Posted by darkpheonix

In response to adding weight without adding weight, you could add fans to the bottom of the robot to draw in air from the bottom, just like those cars that can climb walls. Don't know how much it would increase the normal force though.

Reading R06... It says to me that no devices at all (making contact or not) may be used as a "traction device". The intent is that all robots have similiar traction on the surface. Increasing your force via suction would be a "traction device" in my mind

[DanL]

Some quick suggestions off the top of my head:

Giant Flywheel. For resistance to bumps and bruises, spin up a giant flywheel to help you conserve momentum.

Traction Control. This was mentioned before, but I'll summarize the idea of a traction control system. In a car, you compare the speed of the powered wheels to the unpowered wheels. If there is a difference, that means one set is slipping while the other isn't. The computer cuts a bit of power to the driven wheels until both spin at the same rate. For a 4-wheel vehicle, you can use an accelerometer to get the differential measurement.

Mariocart for Driver Training. Mariocart invented drifting. Blue sparks may be a safety hazard, though.

Pneumatics as Thrusters. Satellites use gas thrusters to control direction. If the surface is low enough friction, this could act as a nice stability augmentation.

Antilock Brakes. Antilock brakes don't necessary cut down on braking distance, but rather they give you control WHILE braking. If you slam on a car that doesn't have antilock brakes and you lock the wheels, the car basically keeps moving in the direction of its momentum vector, regardless of which direction the steering wheel is pointing (conservation of momentum). With antilock brakes, you're switching between static friction and dynamic friction, and in a nut shell, this gives you some control (ie allows you to swerve around the object you're braking for).

Physics 101. Actually, Physics 8.01. For the truly adventurous, check out Walter Lewin's physics videos on MIT's OCW, specifically the lecture dealing with friction. http://ocw.mit.edu/OcwWeb/Physics/8-...il/embed08.htm. This is roughly equivalent to an AP Physics class.

[mray1031]

zyck I think you and I are on the same train of thought. Still wondering about how to implement it though. Lets see if anyone else comes up with it.

Btw. Has anyone thought of just hanging out in the carpet and speeding around everyone? you'd have to be a great shot with those balls but it would be tough to score on you

[gorrilla]

Originally Posted by DanL

Some quick suggestions off the top of my head:

Traction Control. This was mentioned before, but I'll summarize the idea of a traction control system. In a car, you compare the speed of the powered wheels to the unpowered wheels. If there is a difference, that means one set is slipping while the other isn't. The computer cuts a bit of power to the driven wheels until both spin at the same rate. For a 4-wheel vehicle, you can use an accelerometer to get the differential measurement.

Antilock Brakes. Antilock brakes don't necessary cut down on braking distance, but rather they give you control WHILE braking. If you slam on a car that doesn't have antilock brakes and you lock the wheels, the car basically keeps moving in the direction of its momentum vector, regardless of which direction the steering wheel is pointing (conservation of momentum). With antilock brakes, you're switching between static friction and dynamic friction, and in a nut shell, this gives you some control (ie allows you to swerve around the object you're braking for).

ive seen bakes before....would be tricky to get anti-lock brakes,although i dont think they would help that much, maybe if you had traction control and anti-lock brakes?

[waialua359]

All this talk about effectively driving in these low-friction conditions. I would instead think of how the other parts in your kit can help you score DESPITE the poor driving controllability conditions.
Two things off the bat I saw in the kit and my concrete memory of team 25 in 2006. The lazy susan turet (or equivalent) and the camera.

[Dracco1993]

Yes, we thought about staying on the carpet but we decided it would be a bad idea because like he said, you would be an easy target and you will only be able to have at most 1/2 of your robot on the carpet.


P.S. How do you guy get thebluealliance name thing on there?

[Zyck_titan]

Mray

We thought of this, but our team decided not to do it Because;
A.) too much fabrication (time money etc)
B.) too much tuning to get it right (time)

But basically Thrust downward, with it you could dynamically control weight throughout the match, getting advantages of heavier btos and lighter bots, whenever you needed it.

[Dracco1993]

I dont think they will allow anti-lock brakes. They said at the kick-off that the only thing that can control the speed of the tires are the new jaguars and the old things. (I forgot what they are called.)

[DarkFlame145]

Originally Posted by sPod

We cant use OMNI's or traction wheels, only the KOP wheels. any ideas of how to drive?

Very carefully

[Dracco1993]

I still need help on thebluealliance thing please.

[Mike8519]

You can pulse "brakes" electronically. Plus you can control the coast/brake setting on the jaguars with the Digital outputs

[Alan Anderson]

Originally Posted by Dracco1993

I dont think they will allow anti-lock brakes. They said at the kick-off that the only thing that can control the speed of the tires are the new jaguars and the old things. (I forgot what they are called.)

The "old things" are Victor 884 speed controllers from IFI.

Antilock brakes and traction control are implemented using software and sensors. The Victors or Jaguars are still used to control the motors.