OT But may be of interest to some.

[MartB]

I've been away from my desk for some time and upon my return discovered a nice little website for those interested in extreme thingys.
I particularly liked the X Scream, as I've worked on a couple of rides myself in the past.
I like the idea of the random movement combinations, very novel (and brave of the programmers), I was most surprised to learn that it used a Panelview plus operator interface!
Good luck to all who ride in her ! (not that I would mind having a go myself)

check it out at www.controleng.com/extreme

There's also more info at http://www.interactiverides.com/

Mart

 

[Peter Nachtwey]

I like the article about the press

However, the fact that our motion/force controllers were used was not mentioned. Also, I have not ever thought of our controllers a CNC even though the motion/force controller does most of the sequencing.

 

[MartB]

I didn't quite understand one thing I read though and I quote "The redundant controllers function in lockstep, allowing either to take over operation if an error in the other is detected"

What do you think they mean ? I've never heard the term Lockstep before.

 

[rgurin]

When I think of the term "lockstep," I think of events occurring at exactly the same time.

I'm not too familiar with amusement ride programming, but is it possible that the ride program can be running at the same time in both controllers, so that an instantaneous failover occurs if one controller faults?

Rick

 

[akreel]

I'm not too familiar with amusement ride programming, but is it possible that the ride program can be running at the same time in both controllers, so that an instantaneous failover occurs if one controller faults?

That's the idea, basically. But, there is a slight delay when the transition occurs. I don't know if it's long enough to notice on an application like this. But, I do know that the power engineering group that I used to work for thought the hand off took too long for power plant applications (this was around the time of V10 firmware).

For this application, I think I'd skip the redundant CPU. I'm only assuming this, but I'd bet they're relying on ControlNet IO. I'd much rather see the IO cards in the backplane (less chance of IO failure) and use redundant mechanical safety devices, or an independant safety PLC to back up the primary controller. Of course, they COULD put IO cards in the processor racks. But, I think that would defeat some of the features offered by CLX redundancy.

My two cents: CLX redundancy is better applied in continuous process operations, to avoid down time. It's not a safety backup.

AK