Maverick

MichaelB said:
Depends on what is being done and who is doing it. I don't know too many engineers that actually like doing extra work.

Yeah, I'm with you, but personality and skill level have everything to do with the outcome. I'm not saying engineers start with Rube Goldberg machines, but I have to wonder how much design iteration Intamin goes through. I'm thinking not enough.

For example, if I remember correctly, Dragster has two switches to detect the position of every last brake fin. How many hundreds (thousands?) of switches does that make? I can't imagine that any self-respecting engineer would let that stand and not find a more efficient way to solve the problem. Or if you want a really fantastic example, compare the Vekoma flying coaster trains to the B&M model. The Vekoma rides were needlessly complex with a ton of electronics, a desire to recline the trains on the lift (which never worked) since they didn't start inverted... they were a total disaster.

I get that design is a constant process of evaluating the tradeoffs and return for the work. You don't spend a lot of time and money on making a machine cheaper, more simple or more efficient if it's used by one person a few times a year. Heck, I imagine that Intamin's design culture is, "Who else is going to build this? We'll charge the customer whatever it takes, and we don't have to maintain it anyway."

Your last sentence sums up the mentality of many engineering firms in any industry these days.

Coasterkyle said:

The ride will stop in the tunnel depending on how quickly we can dispatch trains. It will stop in the tunnel if the train has not cleared the set of breaks before the turn behind the station. We do not have control over the trims in the tunnel.

That makes sense. So slower dispatch times make it stop to keep trains from coming too close. I prefer it to stop before it launches because it really makes the launch better. People will probably hate me but I hope they are dispatched like this everytime I ride it, :P

I believe it's the opposite. The faster trains are dispatched, the more likely it is to set up in the nearest block. Same goes for Millennium Force and the anti rollbacks on the lift hill. When it's dispatched too early, the train will stop at the top of the lift.

TwistedWicker77 said:

I believe it's the opposite. The faster trains are dispatched, the more likely it is to set up in the nearest block. Same goes for Millennium Force and the anti rollbacks on the lift hill. When it's dispatched too early, the train will stop at the top of the lift.

Oh, ok. I was thinking there were trains after the tunnel trying to finish the coarse so it would stall you at the beginning of tunnel to let them finish. I guess that would be dispatching quickly then. I cant figure things out in my head without seeing it LOL! Im a practical person not theoretical I guess :)

^^yes, from as far as I know, if the second train is dispatched too early that wouldn't allow the first train to make it far enough before the second train gets to the tunnel.

Times I've been there, Maverick either has to long of a line or its broke down. Remember on my last visit September 5, got a ride in during early ride time. Got back on with little wait and our train was about to head out, then they unlocked the restraints and both trains got back in line. At first didn't know what was going on, then we figured out that the six train stopped in the tunnel. Noticed on our first ride, the train slowed down more than usual going into the tunnel. They were able to get the sixth train launched out, and it completed the rest of the course. Next they ran two empty, first one launched out with no problem. Then the second came to stop in the tunnel. We then decided to leave the line and head over to Millennium Force.

Coasterkyle sums up the Maverick situation nicely. As to the brake blades on MF needing prox switches for both the up and down condition: there really is not another weather resistant, vibration resistant, temperature insensitive choice.

When the train launches all the blades must go down for there to be enough energy left to get over the hill. This was a problem earlier in this season with the last launch section not properly retracting brakes. So, the train waits at the tree waiting for the proxes to indicate the block is clear (brakes down and prior train in station) before allowing launch.

Yes, there are a lot of proximity switches.

After the launch and as the train clears each launch section the command is issued to raise the brakes, if a blade does not indicate up, then the next train is held in the station. Otherwise if the launched train rolls back and the brakes are not up... paperwork...

So, will a single blade not retracting or extending cause the train to fail to launch or to safely brake from a roll-back? No.

But, like Picard says: "how many is too many?" There is a critical number of blades in each direction. I will not disclose that here. But, the idea is that the machine needs to be at 100% to be safe with a margin. Could the ride be operated with some blades unsat? Sure. But why would we risk it?

No one is arguing that. The argument is that designing the ride with two switches per blade is awful. The fact that they're moved in groups alone would imply that putting them together on a single rail and then using switches to indicate that larger piece's position would be the first obvious change. (Not my idea... I've seen this on someone else's ride, where a lever is pulled by a horizontal pneumatic piston to raise the series of blades.) Think about it, if you grouped even five of them together you've reduced the number of switches by 80%, and that's assuming you didn't come up with a way to indicate state with one switch for up and down.

But, hypothetically speaking, what if the linkage to the lever that operates a group of brakes fails which in turn causes a group of brakes to malfunction. So now, as the train passes, an entire group of brakes do not raise. That could possibly put the ride in an unsafe condition. As it is now, with each blade operated independantly, you are making the failure of group of brakes extremely unlikely. In spite of the complexity, I think the way it is done on Dragster is the safest way to do it.

Where I think some prox switch savings can come from is the advancing setup in the station. Maverick seems to have less prox switches and moves two trains at the same time just fine. Being a newer design, it seems they learned some things when designing Maverick and that could possibly be retro fitted to Dragster.

No, like the current setup, the default position is up. The piston pulls them down (I know, I phrased it in the opposite fashion). The Millennium Force brakes essentially work this way today, but instead of pulling them down, they're pulled out. And there's still no reason you can't group them together.

I get that default is up. I'm assuming that each brake is spring loaded to default to up, although I'm not 100% sure of that. In any case, if a linkage were to connect a group of brakes, I would assume the spring to default to up would also be part of the linkage. I'm not sure how reliable it would be to have each brake individually spring loaded and have them drag the linkage along every time they go up. If there is a common spring for the linkage, you still have the group failure potential that I mentioned originally.

Are we even sure that most TDD downtime is caused by prox switches? There are a multitude of other reasons the ride can go down. Prox switches seem to be very reliable since there are no moving parts.

There are SO MANY switches, that probability allows for one of them to "miss" when tripped. Look at how quickly they cycle trains when there are no issues, multiply that by how many times those switches cycle. Also, each car triggers a switch, not each train. This adds up to a good chance of a cycle reset.

Explain why you think it is possible to miss a switch? Seems consistent: metal object, switch closes. If you ever watch the status light on the switch, the light changes immediately. I don't see the opportunity to miss.

They are magnetic. Random electromagnetic fields can interrupt one of those triggers. Again, probability over many trains and many switches allows something to miss.

Choosing the correct switch can virtually eliminate those types of problems, which I assume would happen as part of the coaster control system design. Here is an interesting article on prox switch selection, it seems like the biggest potential problem is a false positive, not a miss.

I consider the same either way. Either a double read, a non-read, or a false read will all lead to faults.

Are you sure you're not talking about Dragster? That thing had such unreliable up time this season. I was in line for it as my last ride on closing day, and sure enough it went down 20 minutes to 8. To be in that line more than 15 minutes is almost a guarantee it will go down. Although, it going down just before my ride the previous week resulted in my first rollback.

On the contrary, I rarely noticed Maverick down much at all this year. I rode it countless times, though mostly as my first stop during early entry. But it still seemed to be up and running as I walk by the extra long line throughout the day.

The latter part of this discussion has been about dragster as an example of reliability trouble plaguing intamin rides.

The title of this thread should be "dragster"