Cedar Creek Mine Ride to operate three trains (?)
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As reported on rec.roller-coaster, the Cedar Creek Mine Ride will have a new PLC/safety system installed this off-season making it able to run three trains again safely. Remember, this is off RRC so take it for what it's worth. The post also mentioned that they were going to retrack some of CCMR, making the lifts higher. This one I don't quite believe, but the computer story I do. Now only if they can get back to the golden days of five train operation :)
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Scott W. Short
sshort@mediaone.net
http://welcome.to/midwestcoastercentral
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Scott W. Short
sshort@mediaone.net
http://welcome.to/midwestcoastercentral
I was shocked this season that there were actually times that three trains would have been nice. I actually waited twenty minutes for a ride this summer, something I wouldn't normally do if it wasn't for out-of-town friends.
Now if they could just do something about the lap bars that hurt my precious gems!
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Jeff
Webmaster/Guide to The Point
Now if they could just do something about the lap bars that hurt my precious gems!
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Jeff
Webmaster/Guide to The Point
i kinda like the Mine Ride..it's so QUIET when it runs the course of the track...it's just a neat little ride and we never miss it when we're there. we also ride Cedar Downs about eight times, the bumper cars at least twice, CPLE railroad a lot(mostly to get to the back of the park without having to walk) and the GEEKIEST thing we do is this...big coaster, drive the little cars...big caoster, drive the little cars. they're so SCENIC on some of those courses. but i guess that explains a little better WHY i like Mine Ride..it would be nice to see some improvements on it, but wouldn't that jeapordize any chance it has/had of becoming listed as a classic coaster?
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"I think I scrambled my brain!!"
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"I think I scrambled my brain!!"
Never be fooled by a short line.
Even though there was never any wait for it when it was running three trains, Mine Ride was usually running with full trains, or mostly full trains. Put another way...
3 trains, full: 1,543 pph
3 trains, last car empty: 1,234 pph
2 trains, full: 1,028 pph
It's a difference of more than 500 pph between two- and three trains. The short line merely means that people are arriving at the ride entrance about as quickly as they are boarding the trains. A ride could be doing better than 2,000 PPH and still have no appreciable wait at all. Well, look at Gemini...with six trains running it moves close to 3,400 PPH. Remove a train from the Mine Ride, and if people still approach the ride at a rate of 1,500 PPH but only get dispatched at 1,000 PPH, then you're going to built a significant queue.
Last season one of the CCMR crew members argued that they really didn't need the third train "because they were only getting 14,000 people a day." I had to point out that obviously they needed the third train because at 1,028 PPH they couldn't possibly take more than 14,000 riders. The long line and full trains indicated that they were running at maximum capacity for that number of trains. With another train, their numbers would probably increase.
One of the best demonstrations of the disconnection between length of line and ride throughput was at Darien Lake on the Viper during my first visit. Every time the train went out, there were 25-28 people aboard, and every time the train went out, the station was almost completely empty. With two trains running, people were arriving on the platform just in time to board the ready-to-go train. The passenger arrival rate and the train throughput were almost perfectly matched.
--Dave Althoff, Jr.
Even though there was never any wait for it when it was running three trains, Mine Ride was usually running with full trains, or mostly full trains. Put another way...
3 trains, full: 1,543 pph
3 trains, last car empty: 1,234 pph
2 trains, full: 1,028 pph
It's a difference of more than 500 pph between two- and three trains. The short line merely means that people are arriving at the ride entrance about as quickly as they are boarding the trains. A ride could be doing better than 2,000 PPH and still have no appreciable wait at all. Well, look at Gemini...with six trains running it moves close to 3,400 PPH. Remove a train from the Mine Ride, and if people still approach the ride at a rate of 1,500 PPH but only get dispatched at 1,000 PPH, then you're going to built a significant queue.
Last season one of the CCMR crew members argued that they really didn't need the third train "because they were only getting 14,000 people a day." I had to point out that obviously they needed the third train because at 1,028 PPH they couldn't possibly take more than 14,000 riders. The long line and full trains indicated that they were running at maximum capacity for that number of trains. With another train, their numbers would probably increase.
One of the best demonstrations of the disconnection between length of line and ride throughput was at Darien Lake on the Viper during my first visit. Every time the train went out, there were 25-28 people aboard, and every time the train went out, the station was almost completely empty. With two trains running, people were arriving on the platform just in time to board the ready-to-go train. The passenger arrival rate and the train throughput were almost perfectly matched.
--Dave Althoff, Jr.
First, a question: what is PLC? I assume proximity location something. Has this ride ever been "safety controlled" by computers? I remember in the late 70s or early 80s, I think I remember when the ride ran 4 trains simultaneously.
Regardless, by that time, it did -not- use the separate unloading area. On occasion, the operator had to stop an incoming train on the holding (?) breaks right before the station building.
I _distinctly_ remember that the operator's station had a mirror that looked at the lift hill, and on one of the support beams on the lift (about 7/8 of the way up), there was a strip of orange paint. When the _front_ of the train on the lift reached that paint stripe, the operator released the train in the station (if it was ready for dispatch).
Regardless, by that time, it did -not- use the separate unloading area. On occasion, the operator had to stop an incoming train on the holding (?) breaks right before the station building.
I _distinctly_ remember that the operator's station had a mirror that looked at the lift hill, and on one of the support beams on the lift (about 7/8 of the way up), there was a strip of orange paint. When the _front_ of the train on the lift reached that paint stripe, the operator released the train in the station (if it was ready for dispatch).
At the moment, I think the safety system on CCMR is all relay logic.
A PLC is a Programmable Logic Controller, which is a special purpose computer. Basically, you feed all the sensor outputs to the PLC, and you feed the PLC's outputs to the things you want to control...brakes and lifts, for instance...and program the PLC to emulate a cabinet full of relays: when this happens, do that. It's mostly event-driven. The major benefit of a PLC over relays and timers is that the PLC can be programmed to deal with more signals, the program can be flexible (when this happens, do that, unless something else is true...).
The CCMR has a safety system on it, and it even has some simple automation. For instance, the safety/trim brake outside the tunnel has two reservoir tanks on it, and two regulators...one pressure to stop the train, a lower pressure to trim the train, depending on whether there is a train on the unload brake or not. The trouble is, while the CCMR has a safety system on it, said safety system is not entirely fault tolerant. It is *possible* to override the system in such a way that one can make Bad Things happen. This is, of course, the reason the ride needs a new control system: to make it fault-tolerant so that it will always fail to safe when something goes wrong.
I think the ride has always had some kind of safety system on it, but the present (as of 1999) system is not the original.
--Dave Althoff, Jr. *** This post was edited by RideMan on 1/16/00. ***
A PLC is a Programmable Logic Controller, which is a special purpose computer. Basically, you feed all the sensor outputs to the PLC, and you feed the PLC's outputs to the things you want to control...brakes and lifts, for instance...and program the PLC to emulate a cabinet full of relays: when this happens, do that. It's mostly event-driven. The major benefit of a PLC over relays and timers is that the PLC can be programmed to deal with more signals, the program can be flexible (when this happens, do that, unless something else is true...).
The CCMR has a safety system on it, and it even has some simple automation. For instance, the safety/trim brake outside the tunnel has two reservoir tanks on it, and two regulators...one pressure to stop the train, a lower pressure to trim the train, depending on whether there is a train on the unload brake or not. The trouble is, while the CCMR has a safety system on it, said safety system is not entirely fault tolerant. It is *possible* to override the system in such a way that one can make Bad Things happen. This is, of course, the reason the ride needs a new control system: to make it fault-tolerant so that it will always fail to safe when something goes wrong.
I think the ride has always had some kind of safety system on it, but the present (as of 1999) system is not the original.
--Dave Althoff, Jr. *** This post was edited by RideMan on 1/16/00. ***
Dave,
Thanks for your (as always) lucid explanation of the PLC. I teach computer science at the college level, and I do know what a PLC is, but I must admit I'm sometimes in the dark ages when it comes to how coasters are automated. I never put 2-and-2 together!
Thanks again; I know there are many of us here on CP Place who appreciate the time and thought you often put into explaining things in a clear manner.
Thanks for your (as always) lucid explanation of the PLC. I teach computer science at the college level, and I do know what a PLC is, but I must admit I'm sometimes in the dark ages when it comes to how coasters are automated. I never put 2-and-2 together!
Thanks again; I know there are many of us here on CP Place who appreciate the time and thought you often put into explaining things in a clear manner.
...Not to mention that to run five trains (heck, even to run four...) would require a full crew for the trains in the station. Remember that they tend to use two people on the platform to let everyone out of the train, not five. Those trains have manual lap bars, remember!
Actually, in the year that they had the incident, they moved a couple of block brakes and installed a new optical detector so that they could theoretically run four trains, but I don't think they ever got the chance to try it out.
--Dave Althoff, Jr.
I usually always ride CCMR when I am there-basically cause it is really a fun little ride-
I have found like most that for the most part it is only running 1 train and only allowing 1/2 the trains to be filled.
3 trains is going to be interesting-only because if mind serves correctly the lap bar locks are done manually-alot of extra work for the ride ops!Of course it will be interesting for this year to see if one (unnamed) CCMR ride op kept his promise and got himself another CP tattoo????
Is it Spring yet?????
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Welcome back Raptor riders-how was your flight??
I have found like most that for the most part it is only running 1 train and only allowing 1/2 the trains to be filled.
3 trains is going to be interesting-only because if mind serves correctly the lap bar locks are done manually-alot of extra work for the ride ops!Of course it will be interesting for this year to see if one (unnamed) CCMR ride op kept his promise and got himself another CP tattoo????
Is it Spring yet?????
-------------
Welcome back Raptor riders-how was your flight??
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