Go Down

Topic: Outlaw Pinewood Derby Car (Read 1 time) previous topic - next topic


I am a total newbie to Arudino but I am looking to dominate the first ever open class / outlaw pinewood derby and I want to use an arduino controller so it can be a teaching project later.

I want the car to have a ducted fan unit that will turn on when the starting gate opens and then turns off when it hits the stopper at the bottom.

I'm guessing I just need an accelorometer activated switch, a motor control, and a main board and the patience to figure out the programming. Am I oversimplifying or is there more to it than that.



An accelerometer is one way. But I think you can do it without an Arduino at all. Have a button on the front bumper which is presses against the starting pin. Have this button connect to a relay that activates the fan. So as soon as the pin drops, the fan starts. Then when the car hits the end of the track the same button will stop the fan.


Having just done the Pinewood Derby (1st grade version) a couple months ago, I have a couple questions about this Outlaw bracket.

Do you still have to hand it to one of the volunteers to actually place it at the start?  If so, you may not be able to "arm" the trigger, or push any buttons.  I think the accelerometer might be the best option (unless they allow remote control starts).  Maybe a proximity detector, where if something is right up against the nose, then it "arms" and when it is no longer there, the engine starts.

Also, rather than an accelerometer, maybe a gyro?  If the engine kicks on when the car moves forward, I wonder if it might actually jump forward off the track a bit, maybe getting airborne.  But, with a gyro, when the pitch goes nose-down past... maybe 30 degrees from level, then maybe light the fires (metaphorically speaking).

The track is a defined length, right?  You will only need the fan to run for a couple seconds. You can figure out about how long you will need it on, and just program it to run for that amount of time.

Just spitballing some ideas.



You could save yourself over 40 dollars and just use a wheel speed sensor and a 555 timer acting as a 'one shot' triggered by the wheel turning. The wheel will need to turn a bit before the system switches on, so it's not as immediate as the suggestion for a switch on the nose, but it's not dependent on any set up so will work again even if mis fired and will cost less than five dollars to build.

On my cars the wheels are turning 70 times a second, and I have a resolution of once per second. I will increase this to two or four times a second by adding more strips, you might go higher so that you can start the fan after 1/8 or 1/16 of a turn.


Duane B

Read this
then watch this



I had the same idea for a outlaw pinewood derby entry and was wondering what your ultimately solution was?

Go Up