Electric Vehicle C

[MontyBuilder]

It just means that you're connecting that pin to ground (negative). Doesn't matter where you physically connect it to, as it's going to be a negative-ground system. Theoretically you don't need that wire though as you only need to break the circuit.

so it isn't necessary
i can take it out
hb

[Dark Sabre]

Right, you don't actually need it unless you are wanting to try the eddy-current brake.

"A simple application of Lenz's law can be seen in the eddy current brake. A simple eddy current brake can be easily made by connecting the two terminals of a DC motor."

The motor stopping and the wingnut jamming against the switch will probably be enough, but try it the other way if it isn't.

[MontyBuilder]

i thought exactly the same thing

thanks that's great

ive designed it on the paper,
and I've found the best way to fit it on a car

the only other thing to do before starting to build is trying to equalize the mass on both sides of the car so it goes striaght, is that actually necessary since the car is going at a very low velocity?

[MontyBuilder]

oh
how much $ is a momentary switch?

[andrewwski]

Probably $3-$5 retail.

[MontyBuilder]

what's wrong with using one battery instead of 4?

if you have an extremely fast motor, isn't the slower the better because your results are more consistent and easier to calculate?

after those, im done with questions so i can stop bugging everyone

[gh]

There is no advantage. Use what power source you should use/want to use for your motors. I guess battery voltages vary between cells. If you use more than one, they end up averaging out the voltage variation. Still, use a battery configuration that suits your motors.

If you use electronics, you may be required to provide a certain voltage to the circuitry, and that may not be fulfilled by a single alkaline cell.

In general, motors should be geared down to provide higher torque and lower speeds.
This will let them negotiate changes in friction, etc. so that acceleration remains similar across different conditions.

Aim for 45 second runs; if your absolute time error is constant no matter how long the run takes, then having a long run reduces relative error (which is what your score is based on).

[andrew418]

Hey guys

I was going to post some pictures of my EV, but it looks like someone did it for me here:

http://gallery.scioly.org/details.php?image_id=1304
http://gallery.scioly.org/details.php?image_id=1306
http://gallery.scioly.org/details.php?image_id=1305
http://gallery.scioly.org/details.php?image_id=1286
http://gallery.scioly.org/details.php?image_id=1285
http://gallery.scioly.org/details.php?image_id=1283

If you have any questions or want a better pictures of anything, just let me know, and I'll see what I can do

It didn't do all that well at nationals, I made some pretty stupid operator error mistakes, but what can you say...

[fullofit]

I don't like to complain about how events are run because I know how hard the volunteers work to make SO Nationals happen, so I will call this a suggestion rather then a complaint. If you are going to run an event you should carefully look over the rules. In this case the rules specifically state that if the floor has boards running in one direction, the track shoudl be set up across the boards not parrallel to them. If we had known that we were going to have to deal with large cracks parallel to the track we could have designed our EV to deal with that issue but the rules told us that we would not have to deal with that issue. It would have been easy to run the scrambler and EV tracks across the boards rather then parrallel to them. Perhaps next time these events are run the coordinator can take the track surface into account.

[Dark Sabre]

I don't like to complain about how events are run because I know how hard the volunteers work to make SO Nationals happen, so I will call this a suggestion rather then a complaint. If you are going to run an event you should carefully look over the rules. In this case the rules specifically state that if the floor has boards running in one direction, the track shoudl be set up across the boards not parrallel to them. If we had known that we were going to have to deal with large cracks parallel to the track we could have designed our EV to deal with that issue but the rules told us that we would not have to deal with that issue. It would have been easy to run the scrambler and EV tracks across the boards rather then parrallel to them. Perhaps next time these events are run the coordinator can take the track surface into account.

Could you point to the section and number where it specifies the direction of the track, I'm not seeing it