I posted this info a few weeks ago, but I think it may clear up some of the questions that are in this thread...
The Test Track ride control system is the most complex system in operation right now in WDW... Here's a little info...
Each car has three onboard computers which control various aspects of the Test Track experience. Audio and video, vehicle velocity, breaking, along with a a gamment of safety checks are controlled and monitored by these computers. (figure approx. 25 cars on track at once)
The onboard computers are also communicating to three mainframe computers located within the building. Basically two of the computers do exactly the same thing, one is a back-up. They are both sending and receiving information from the cars and are checking each other to make sure that everything is within set parameters as far as where the vehicles are and what they are doing. The thirds mainframe computer specifically monitors safety parameters for the vehicles. Look at it this way. The car is sending information to the mainframe. If the first computer misses this information chances are that the second one will catch it... If all else fails the third computer will capture the information and decide what needs to be done to keep everything within safe parameters.
Some of you may not understand this, but the information sent to and from the cars is sent in packets. Basically just like e-mail or internet information is sent. The data travels through the low voltage rails under the track back to the mainframe computers. This is often where problems arise... Occasionally the packet of information gets disrupted or lost. If this happens the mainframe computers will often stop the ride. Basically the mainframe computers expects a packet to arrive from each car at a specific time. If the car does not send the packet or if it gets disrupted the mainframe computers suspends ride operation until the ride operators can verify that everything is within safe parameters. It is for this reason that the ride "breaks down" so much...
Ok, so on occasion a car will just break down. They are mechanical just like your own car... The only difference is that the cars at Test Track run approximately 120-150 miles per day, everyday of the year... Do the math, but it adds up to approximately 43,000-54,750 miles a year. This is just a little bit more then you would run your family car, considering the average is 12,000 miles a year... Because of all of this stress on the cars they do have a tendancy to break down more often then your car even though they do nightly maintence checks on each and every car...
When you have free-moving 1 ton vehicles carrying 6 passangers each, traveling at 65 miles per hour, spaced 10 seconds apart you have to think safety!!! There is NO room for error at Test Track... The unfortunate side effect of all this is that the ride is down a lot more then other rides at WDW. Look at it this way though... Disney wants you to be safe. They have designed an amazing ride that, in a technical aspect, is far superior to anything else they have ever designed. The ride basically runs itself. Ride operators are only there to make sure the computers are doing what they are supposed to be doing. If the ride does go down it is for the safety of the guests riding it, and even though it does go down quite often Test Track is one of the safest rides in the world... So give Test Track a break...
