Switching Launch Directions...

I never really followed the first Impulse's construction so I'm not entirely sure how the ride changes directions. I first though that there were two sets on LIM's with half facing one direction and half facing the other. Recently in Physics, we have been going over current flow in relation to magnetic fields.

I assume that this is how it works. There are two different current flows to the LIM's in order to launch the train forward, electric current is run backwards trough the LIM's which creates a magnetic field to propel the train forward, and then the computer switches the electric current flow to generate a reverse magnetic field to propel the train backwards. Then this is repeated.

Am I correct in how the train is launched in relation to the current flow and magnetic field?

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IU shocks the world!

(and screws up 99% of people's brackets. :))

The LIMs use 3-phase alternating current. So current flows both ways through the LIM coils all the time they're powered up.

In order to get launch force in both directions, logically they would have to switch the #1 and #3 phases...so to launch in one direction, the LIM coils should fire "1-2-3-1-2-3" and to go the other direction they should fire "3-2-1-3-2-1". That could be easily done with a double-pole contactor, or it can be done with a bi-directional motor controller that drives each phase independently of the input power phase.

My page about LIMs is as much about 3-phase power as it is about LIMs.

--Dave Althoff, Jr.
(cleaned up the URL)

*** This post was edited by RideMan on 4/4/2002. ***

I would say an easy way to think of the LIM's is to think of magnets... Hold the North end to the North end, you'll feel the propelling. And imagining the braking being Applying the North end to the south end like normal magnet attractions.

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- Chris -
http://www.thepointol.com/~simplycp
Computer Science - Ashland University
Witches' Wheel/Monster - 2002
3rd Shift Trash Removal - 2001

This may be a little random but I didn't want to start a new thread... Why are they launching toward DT? All your going to see is beige walls and parking lot. Why not the other way with more of a "veiw" of the park?

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"Your obssesed w/ that place aren't you?"

I was about to do the same...

Also notice the big wall to your left blocking the view of the lake. So when you launch you get a nice view of a brick wall and a warehouse.

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*** This post was edited by Joe E. on 4/4/2002. ***

The view vertically would be basicly the same facing the opposite direction. There would only be about a second to see the park versus DT.

Would you rather have the power shed on the lake side were it blocks the riders from possibly being hit with sand at extreme speeds and where people on the midway can see the ride, or on the midway side blocking some of the ride and leaving the launch area exposed to getting sand blasted? Besides the shed doesn't even block most of the straightaway.

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MF count: 23

I'd rather have the shed below like on S:UE so it doesn't block anything ;)

Like CP_bound said, the shed is not that long, probably only 3/4 of the staightaway.

Besides...who is to say you couldn't turn the ride around and leave the shed in the same place? I always thought the ride seemed like it was "backwards." Seems to me like the rear spike should be by DT.

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James Draeger
http://draegs.livejournal.com
"Whose bright idea was it to get him talking about Cedar Point?!"

I think since the ride is basically symmetrical it might be a little bit easier to turn the train around ;) I'm assuming it would be easy to turn the train around with no problems.

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- Chris -
http://www.thepointol.com/~simplycp
Computer Science - Ashland University
Witches' Wheel/Monster - 2002
3rd Shift Trash Removal - 2001

ACEerCG said:
I always thought the ride seemed like it was "backwards." Seems to me like the rear spike should be by DT.

Yeah, when I first saw the footers I imagined blasting off towards Maggie and breakers with the sun getting low, casting shadows down from the old tree's under sky of purple hew, and the waves on the lake touched with gold from the dying sun. But noooo! ;)

I wondered the same thing, and I can't think of a single reason not have pointed it the other way, other than positioning of the station.

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Jeff
Webmaster/GTTP, Sillynonsense.com
"As far as I can tell it doesn't matter who you are. If you can believe, there's something worth fighting for..." - Garbage, "Parade"

I think the position of the station must be key here. If I remember correctly, isn't the launch track tucked in behind the Disaster Transport little helix thingy sticky-outy bit? :)

On one of these Impulse rides you want the launch out of the station to be forward so as to push riders back in their seats. Would there have been enough room to switch the launch straightaway and the station and go the other way with it? And if they had done that, would the entrance interfere with the Disaster Transport entrance and the queue that forms there?

--Dave Althoff, Jr.

RideMan said:
little helix thingy sticky-outy bit?

With that and "cage thingy," no one can beat our dedication to technical terminology. ^_^ Hee hee! I love this site!!!

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~Lee~

Group Sales ATL '01
Park Admissions TL '02
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Who's afraid of the big bad... sea gull?

It's not as easy as "turnign the train around". Software would have to be re-written and the communications interface with the train would have to be re-done.

And considering last I heard, the comm system between train and controls is a new system that's only been used on one other ride so far. Could be more but I know of at least one VERY recent ride using the same system that had some comm problems.

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June 11th, 2001 - Gemini 100
VertiGo Rides - 82 Farewell my good friend..

How close to the DT sticky-outy helix whatchamacallit tubed tunnel does the up side of the WT track go? Could it be a "danger" effect thinking you're going to crash into DT and then suddenly twist away from it? Or am I just way off base here?

It's not very close if you ask me.

A bigger issue in "reversing" the ride is that the LIM's are more dense in the station than the rest of the run, presumably to get it moving from a dead stop.

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Jeff
Webmaster/GTTP, Sillynonsense.com
"As far as I can tell it doesn't matter who you are. If you can believe, there's something worth fighting for..." - Garbage, "Parade"

Ok Makes sense. Thanks Red Garter I would never have guessed there being communication stuff with the train too. It just looked to me like there was a metal plate or something that went up into the LIMS. I figured it would be easy for them to turn the train around for a backwards launch but I guess not :) You learn something new everyday on this site.

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- Chris -
http://www.thepointol.com/~simplycp
Computer Science - Ashland University
Witches' Wheel/Monster - 2002
3rd Shift Trash Removal - 2001

Interesting...

The train has the timing comb on it (first used on Volcano) and I think I remember seeing three electrical contacts...I figure that's "open bars", "bars OK" and "ground." That's as sophisticated as the train needs to be unless they're getting fancy so as to identify which row isn't "OK" when there is no OK signal...

What more communication would be needed with the ride control?

--Dave Althoff, Jr.

None that I can see! And since every car has its own contact, you can at the very least narrow it down to the right car.

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Jeff
Webmaster/GTTP, Sillynonsense.com
"As far as I can tell it doesn't matter who you are. If you can believe, there's something worth fighting for..." - Garbage, "Parade"