Braking Mechanism

[cheese]

As I've read through the forums, the only thing people have come up with is this:
A wingnut spins freely (not constrained by any channel therefore not moving side to side on the axle) on the long 8m stretch.
When turning back, the wingnut somehow catches a channel/passthrough and causes the wingnut to move toward a side and braking.

The only problem I see is, how do you let the wingnut spin freely in one direction but not in the other? If there is only 1 wing (one has been cut off), it still spins 360 degrees around the axle, covering all the possible area around the axle. So when you turn it the reverse direction, it won't hit anything because otherwise it would have hit it before.

Hopefully this makes sense, just trying to cause some more conversation about it.

[Alex-RCHS]

As I've read through the forums, the only thing people have come up with is this:
A wingnut spins freely (not constrained by any channel therefore not moving side to side on the axle) on the long 8m stretch.
When turning back, the wingnut somehow catches a channel/passthrough and causes the wingnut to move toward a side and braking.

The only problem I see is, how do you let the wingnut spin freely in one direction but not in the other? If there is only 1 wing (one has been cut off), it still spins 360 degrees around the axle, covering all the possible area around the axle. So when you turn it the reverse direction, it won't hit anything because otherwise it would have hit it before.

Hopefully this makes sense, just trying to cause some more conversation about it.

I believe another way was addressed, although I forget who said it. The idea was that a one-winged wingnut would be constrained by a bar or edge of some sort so it can't spin freely on the forward route, but will travel left/right as normal. Then one the reversal the wingnut will travel backward just as it normally would, except now there is some lip/object/edge on the bar/edge that the wingnut is sliding along that will stop it. This works because the wingnut will be touching different sides of the bar/edge that it slides along on the way forward vs. on the way backward, and the object that serves to stop the wingnut is only on the side of the bar/edge that the wingnut is touching when the car is reversing.

[cheese]

Ok that makes sense. I happened to come up with something just like that right after writing that question.

[joshyeram]

Can you clarify that with a diagram? I am still not sure how the vehicle will stop when it reverses after it travels the 8m. If there is a nut for an example on the threaded rod, the vehicle will stop before the 8m(since it can't go further than that with the restriction).

[sdececco]

Can you clarify that with a diagram? I am still not sure how the vehicle will stop when it reverses after it travels the 8m. If there is a nut for an example on the threaded rod, the vehicle will stop before the 8m(since it can't go further than that with the restriction).

The only problem with the wing nut breaking system is the car needs to go 8 m forward and 1-2 meters back. Meaning the wing nut breaking from last year wont work. If you have any 3d printing software i suggest creating a one way door to let the wing nut pass one way but not the other.

[petal]

Just curious. When the car brakes, is your drive arm all the way down (all the string has winded off the axle) or does the car stop with the drive arm still at an angle to the car (some of the string is still wrapped around the axle)?

[Dreamz]

Just curious. When the car brakes, is your drive arm all the way down (all the string has winded off the axle) or does the car stop with the drive arm still at an angle to the car (some of the string is still wrapped around the axle)?

For us, it really depends on VTP location.

[mnoga]

Just curious. When the car brakes, is your drive arm all the way down (all the string has winded off the axle) or does the car stop with the drive arm still at an angle to the car (some of the string is still wrapped around the axle)?

For us, it really depends on VTP location.

If running Regional rules most likely the arm would be still be up with some off the string still wrapped on one of the axles. State rules the arm would probably still be up at a decreased angle except for perhaps the longest distances. And for National Rules the string would fully detach from its axle and the arm would end up all the way down.

The previous paragraph describes a car designed to run all three rules with minimal modifications. You could, however, tune your car to use more energy on the forward leg and less on the backward leg for (say) Regional rules. You might be able to gain a second or two on the forward leg with this strategy.

[MTV<=>Operator]

Just curious. When the car brakes, is your drive arm all the way down (all the string has winded off the axle) or does the car stop with the drive arm still at an angle to the car (some of the string is still wrapped around the axle)?

For us, it really depends on VTP location.

If running Regional rules most likely the arm would be still be up with some off the string still wrapped on one of the axles. State rules the arm would probably still be up at a decreased angle except for perhaps the longest distances. And for National Rules the string would fully detach from its axle and the arm would end up all the way down.

The previous paragraph describes a car designed to run all three rules with minimal modifications. You could, however, tune your car to use more energy on the forward leg and less on the backward leg for (say) Regional rules. You might be able to gain a second or two on the forward leg with this strategy.

Can you elaborate on how one would do what you described in the last sentence