LIM's versus LSM's

Does anyone know the acceleration differences of linear synchrounis(spelling?)versus linear induction motors. I think Superman the Escape at MM uses LSM's versus Mr.Freeze(SFSTL) using LIM's. Are they basically out of the question when it comes to giant hills like Top Thrill Dragster because of the length of track that would be required to reach 100+ m.p.h.?
What do the impulse coasters use? Do they use ab "impulse" motor or is that just a name?

Kennywood Team Member Since 2003 Kennywood is CLOSED
Basically a LSM (Linear Synchronous Motor) uses electromagnets to repel each other and move the trains.

A LIM (Linear Induction Motor) doesn't use magnets at all. Inductors (which are basically a coil of wire) are used to create an electric field that moves a fin of conductive material (usually aluminum).

That's LIM v. LSM in a nutshell. Somebody else can bother with the EE jargon.

isn't that similar practice though, even though it doesn't use magnets, it uses conduction and repulsion?

Also, the last RollerCoaster! magazine I received from ACE had a nice little article about the history of LIM's on rides and the difference.

Hill size is all a matter of what you're willing to spend on what propulsion system. Intamin seems to feel that their hydraulic design represents the best compromise for very tall coasters, and they have a lot of experience with LIM's. I don't see any technical issues with using LIM's for very tall hills, but I suspect that the cost could become quite high.
Wasnt the initial problem with the LSM's the timing factor...each stator must be fired a fraction of a second after the one before it?

It seems that most magnet/electric field launching systems have gotten the basic kinks worked out so its only a matter of time before the hydraulic systems will become more reliable.

What was the first use of magnet/electric field launching system anyway? I thought it was Space Mountain and Big Thunder Mtn. at Disney.


...and such

Big Thunder Mtn. at Disneyland I believe. Its uses LIM to move trains in and out of the stations. They are also in the transfer tracks.

Strange how Vekoma got it right and perfect the first with LSM and Intamin got major problems with them.

The first "LIM launched coaster" was PKI's FoF.

The first "LSM launched coaster" was SFMM's S:TE.

If other rides used LIMs to move trains around previous to that I don't know.

If I'm correct, TTA (aka WEDway People Mover) at Magic Kingdom uses a LIM system and opened 1975. Obviously it's not a coaster, but it's interesting to see that the technology had been used in a ride application far before coasters.

WEDway uses a system most like a maglev train according to everything I've read... so I'd guess that's most like LSM, not LIM.

Regardless, it does use magnets to move the vehicles around and maintains it's cool factor to this day.


Absimilliard said:Strange how Vekoma got it right and perfect the first with LSM and Intamin got major problems with them.

Ummm...Vekoma...only uses them to transfer trains out of the station and on the transfer tracks...Intamin...uses them to launch trains at over 100 mph...now think about it for a second...which is bound to have more problems? Duh!


Haha no I'm not giving Patrick the finger

Ummm...Vekoma...also uses them to launch trains 0-57mph in 2.8 seconds on rides such as Rock 'n' Roller Coaster. Duh!

-Lusty Lil 2004 Millennium Force crew
Rctycoon2k's avatar
LustyLil, Vekoma used them for launches after Intamin perfected it, if you are going to be an ass, be a correct ass.

*** Edited 10/20/2004 2:24:32 PM UTC by Rctycoon2k***


Shaun Rajewski
Founder, Lead Developer
Epic Web Studios, LLC


BigJim4Life said:
Intamin...uses them to launch trains at over 100 mph...Duh!

Since we're correcting each other here... what Intamin coasters use LIMs to go that fast, BigJim?

Also, RnRC uses LSM, not LIM- two totally different technologies. To my knowledge there are no Vekoma LIM-launched coasters (somebody correct me if I'm wrong).

Rctycoon2k's avatar

BigJim4Life said:

Absimilliard said:Strange how Vekoma got it right and perfect the first with LSM and Intamin got major problems with them.

Ummm...Vekoma...only uses them to transfer trains out of the station and on the transfer tracks...Intamin...uses them to launch trains at over 100 mph...now think about it for a second...which is bound to have more problems? Duh!


He is talking about LSMs, not LIMs.


Shaun Rajewski
Founder, Lead Developer
Epic Web Studios, LLC

There certainly is a difference between using linear motors for launches and using them for low speed motion. The use for low speeds was orginially perfected I believe for people movers such as WEDway and the shuttle trains in airports.
If you all want to correct each other, then why has nobody mentioned that for Superman: The Escape, Intamin licensed the LSM technology from Vekoma?

(Assuming, of course, that the information in the Rollercoaster! article is correct)

--Dave Althoff, Jr.


Michael Darling said:
The first "LIM launched coaster" was PKI's FoF.

They tested PKD's first so technically it would be the first LIM launched coaster.

Both PKI's & PKD's were technically the first as they both opened to the GP the same year back in 96.
no,,,PKI's tested first, based on my info Hmmmmm.

"If you are going to be an ass, be a correct ass"

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