Rippin' Rocket -> Impulse

(the "WT with knex" thread was a bit polluted, so I started a new one...)

Jeff inquired about using the Rippin' Rocket launch motors to go both ways with an Impulse-type coaster.

As someone else noted, it wouldn't take much to reverse the motors on cue. But it occurs to me, just based on the similar-design Six Flags Cool Coaster launcher, that while the reversing controls would be dead-easy, I doubt that the launcher could spin down, stop, reverse direction, and accelerate to full speed quickly enough to do an Impulse coaster.

But perhaps it would be possible to modify the launcher. Split the launcher in half, and attach a hinge to the bottom of the unit to hold it together, and use a spring or two to hold the halves together. Then add a solenoid to push the unit apart just enough to totally miss the train as the train passes through.

Instead of reversing the launchers, run one launcher in each direction, and use the solenoids to engage and disengage each launcher on command. That way the launchers can run continuously at full speed, only engaging with the train when the train is running in the proper direction.

Any thoughts from the engineers out there?

--Dave Althoff, Jr.

Rideman, you are wicked smart, but I still need a few engineering degrees to catch up with your ideas lol.

Why? I don't have any engineering degrees...

--Dave Althoff, Jr.

I thought a little about putting the two launchers on a rocker just as an experiment. When it would launch one way I think it would cause it to kick and drop the other motor down. Just silly speculation on my part, I don't have the patience to try.

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Jeff - Webmaster - GTTP - Sillynonsense.com
DELETED! What time does the water show start?

The problem I see with that, Jeff, is that while the basic idea makes sense (you're capitalizing on Newton's 3rd Law), by expending some of the energy provided by the launcher in order to move the launcher, you're reducing the amount of force you can put on the train. You're also running the risk of having it kick down before the train gets through, which might actually slow the train down...or worse.

Depending on the design of the launcher, using a rocker might be the way to go, but I think you'd need some kind of external power unit to actually move the unit and to lock it in place as it powers the train. A counterweight on one side and some kind of linear actuator on the other would probably do the trick...

--Dave Althoff, Jr.
Where does one get a solenoid with a 6" throw? :)

One other thing that might interest you, Dave, is that the motors have a jack for an external power supply, so altering the control (and speed) of the motors might not actually require taking them apart.

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Jeff - Webmaster - GTTP - Sillynonsense.com
DELETED! What time does the water show start?

I'm reminded of a toy train set I had when I was a kid - to control it, you plugged in this control box with a lever. Push the lever 90* one direction and it went full speed forward, pull it back 90* and it went full speed reverse, but more importantly you could control the speed to half-throttle, to barely crawling.

If you went to a hobby shop you could probably pick up a box like that and make the proper connections with the motors. That could take some electrical engineering work, though.

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Tommy Penner - YoYoBaybeeMan
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Yes, but you still get back to the basic problem...

It takes the launcher some time to reach full speed. If it is running at full speed and you reverse the polarity on the motor, it isn't going to instantly reverse direction and start running at full speed. Newton's First Law still applies.

At least that's what I think would happen. I know that if my ceiling fan is running slow and I reverse the direction switch, it takes ten seconds of the motor coil running in reverse before the rotor stops...and several seconds more before it gets up to speed. Now these launchers have considerably less mass, but still...

--Dave Althoff, Jr.

It could work, I believe. I haven't seen the size/mass of the motors, but if they're similar to the motors on r/c cars, they should reverse nearly instantly.

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Tommy Penner - YoYoBaybeeMan
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