Battery Buggy B

[andrewwski]

you could just put two nuts on the winged axle.
as they spin, they should travel in towards each other.
eventually, the nuts will get so tightly wound, that the threaded axle won't be able to move anymore, and the vehicle will stop.

Are you saying two wingnuts on the same axle? They'll both travel in the same direction. Unless you mean one nut on each axle? Which would be useless, as unless you adjusted them perfectly, one would not actually do the stopping.

or here's an even easier idea.
wound a rubber band tightly around a part of the threaded axle.
then get the nut on the threaded axle (position depends on distance that should be traveled)
and then have the axle spin until the nut is blocked by the rubber band.

i hope someone understood that.

Somehow I don't think you'll get accuracy from a rubber band. It's going to move around and the wingnut will move a different distance each time. Much better to use something solid. Generally the frame of the vehicle, where the axle passes through, is a good stopping point.

Either way, you're going to be mechanically stopped but the motor will still be running, or attempting to run. That's not going to be good for the motor or any attachments, as it's still going to be trying to turn.

[robotman]

you could just put two nuts on the winged axle.
as they spin, they should travel in towards each other.
eventually, the nuts will get so tightly wound, that the threaded axle won't be able to move anymore, and the vehicle will stop.

or here's an even easier idea.
wound a rubber band tightly around a part of the threaded axle.
then get the nut on the threaded axle (position depends on distance that should be traveled)
and then have the axle spin until the nut is blocked by the rubber band.

i hope someone understood that.

i usually use a wingnut on my axle with two nuts that are locked together so that the wingnut spins toward and when it hits the locked nuts it locks the axle stoping motion

if you do it that way it is somewhat easy to attach a limit switch

Somehow I don't think you'll get accuracy from a rubber band. It's going to move around and the wingnut will move a different distance each time. Much better to use something solid. Generally the frame of the vehicle, where the axle passes through, is a good stopping point.

Either way, you're going to be mechanically stopped but the motor will still be running, or attempting to run. That's not going to be good for the motor or any attachments, as it's still going to be trying to turn.

i agree i think the rubber band would be fairly inaccurate and if you are using any type of axle brake you will need to incorporate a switch that will shut off the motor when the brakes lock this will prevent wear on the engine and gears and also can create more accurate stopping if you adjust it right

[bob3443]

i'm kind of lost in this so can someone give me a crash course? What are the NO, NC, P or any other things i may see? What's Volts Alternating Current? whats the point of a connector in the picture? The connector in the picture is just to connect the battery pack to the wires right? also how would the NO from the micro switch be connected to another wire? Everything else is basically like scrambler right? wing nut, winding the wheels back, etc.? Also do you advise using a scope to line up the buggy? Can anyone give me the basic rules because my coach hasn't given them out yet and I want to get a head start. Thanks in advance.

[robotman]

the NO you are hooking it to the negative wire from the motor going to the battery

the P goes to the posititve terminal of the motor a

the NC has no function except to hook up the positive wire from the batter/switch to complete a circuit

the opjective is to make a car that can go between 5-10 meters as fast as possible

and the car will be fairly similar to a scrambler you just place the micro switch so that it gets activated when the brake stops the car

[fleet130]

What are the NO, NC, P

These are the conventional labels used for the terminals on a switch.
NO – Normally Open
NC – Normally Closed
C – Common

The “C” (or “P” in the diagram in the post above) is connected to either the NC or NO terminal, depending on whether the switch is actuated.

The Normally Closed (NC) terminal is connected to the Common (C) before the switch is actuated. When the switch is actuated, the Common (C) terminal is disconnected from The Normally Closed (NC) terminal and connected to the Normally Open (NO) terminal

What's Volts

Volts are the units of measurement for Electromotive Force. Electromotive Force is a force that causes electricity to flow in a circuit.

Whats the point of a connector in the picture?

This allows for easily replacing the batteries. If a battery holder is used, it may not be necessary.

Can anyone give me the basic rules because my coach hasn't given them out yet and I want to get a head start.

While you’re waiting for the rules, get a head start by going to the library for information on basic electrical circuits and robotics (this is a robotic event). Use Google, Bing or your favorite internet search tool to find information on the internet. Start with terms you have heard about and use the results of those searches to broaden your search. A Google search for “NO NC C” returned the following page:

http://www.installalarm.com/nonc.htm

Depending on other people to feed you the knowledge is a losing proposition.

[andrewwski]

What's Volts Alternating Current?

Exactly what it sounds like, volts of alternating current.

Volts measure voltage, or electromotive force. One volt is equal to one joule of energy per coulomb. Coulombs measure charge transferred per second. One coulomb is equal to one ampere per second, or 6.241x10^18 elementary charges (transferred electrons). In essence, voltage is how hard the electricity is being "pushed." If one were to think of a hose with water flowing through it, the amount of water would be the current, and the pressure of the water would be the voltage.

Alternating current involves the charge regularly changing direction. Most alternating current, such as that delivered to your house, is transmitted in a sine wave. In the US, alternating current that you obtain from an outlet is 60 Hz, or 60 cycles per second.

AC voltage, therefore, is a tad more confusing to measure. The voltage is constantly changing, usually going from a positive voltage to a negative voltage. Peak voltage is the highest voltage that is reached. AC voltage is commonly measured as the root-mean-square (RMS). For a sine wave, the V(RMS) is found by dividing the V(Peak) by sqrt(2).

[bob3443]

Ok, thanks for the info. Now i basically get everything, BUT... in this image

whats the point of the NO on the microswitch to the negative wire? Also, whats the name of the power switch with the NC, NO, C/P? i can't seem to find it anywhere. In Electric vehicle, i see that to start the car they mostly push something down to start it like a stick. Should this concept be used because if you hit a switch it might shift the car or something? Do i really need to worry about Volts Alternating Current, even though i think i pretty much get it? i'm planning to start after i get the official rules.

[robotman]

i am not sure the specifics but the NO makes it a complete circuit when the switch is closed stopping energy flowing to the motor and sends it back to the battery

What are the NO, NC, P

These are the conventional labels used for the terminals on a switch.
NO – Normally Open
NC – Normally Closed
C – Common

The “C” (or “P” in the diagram in the post above) is connected to either the NC or NO terminal, depending on whether the switch is actuated.

The Normally Closed (NC) terminal is connected to the Common (C) before the switch is actuated. When the switch is actuated, the Common (C) terminal is disconnected from The Normally Closed (NC) terminal and connected to the Normally Open (NO) terminal

fleets post shows exactaly how it works

[andrewwski]

Ok, thanks for the info. Now i basically get everything, BUT... in this image

whats the point of the NO on the microswitch to the negative wire?

It forms an Eddy Current Brake. If you look through last year's Electric Vehicle thread there's some discussion on it - you don't necessarily need it, as the motor will stop running when it's no longer attached to the power supply, however the Eddy Current Brake will act as it sounds - as a brake, and slow the vehicle down faster and likely more consistently.

Also, whats the name of the power switch with the NC, NO, C/P? i can't seem to find it anywhere.

That would be a SPDT (Single-Pole, Double-Throw) switch. Radioshack will have them.

In Electric vehicle, i see that to start the car they mostly push something down to start it like a stick. Should this concept be used because if you hit a switch it might shift the car or something?

Electric Vehicle rules required the vehicle to be started by a pen, pencil, rod, stick, etc - it was against the rules to touch the vehicle to start it.

Do i really need to worry about Volts Alternating Current, even though i think i pretty much get it? i'm planning to start after i get the official rules.

Well, I don't think you're going to be using AC with a Battery Buggy, seeing as the power source is batteries. Unless there's some kind of written component to it (I doubt it, but I don't have the rules).

[Cyberdyne-850]

The soinc.org site says they won't start responding to questions for 2010 season until October, so I'm hoping that someone might respond to my question here.

In section 2d of the 2010 Rules Manual, it says: "Electric components shall be limited to batteries, wires, motors, switches, resistors, capacitors, and mechanical relays." Then we viewed the current Electric Vehicle DVD available from soinc.org, and it showed many entries from last year with microcontrollers. We are assuming this is a difference between E.V.'09 and B.B.'10.

Can someone confirm that microcontrollers are definitely NOT ALLOWED for "2010 Battery Buggy B"? Thanks.