On the back of the OTSR there are two hydraulic cylinders each side. As the rider pulls the restraints down, hydraulic fluid is 'sucked' into the cylinders. Once the OTSR are in a safe and comfortable position and they have been checked, the ride operator closes the valves which allow hydraulic fluid to both enter and leave the cylinders. The hydraulic system allows the restraints to be pulled down and locked in any position to better match a rider's body dimensions. In the extremely unlikely event when both locking cylinders fail, the restraints are still held down by a seat belt. Because the riders pull the restraints down themselves it allows quicker loading times meaning more people can ride the roller-coaster.
Intamin's magnetic braking system allows the high speed roller-coasters to have a very smooth stop compared to conventional friction brakes. The friction brakes use a clamp which goes over brake fins. The contact of these two materials creates a large amount of friction stopping the train. However this is often quite rough and uncomfortable because of the high speeds (the King-da Ka accelerator roller-coaster travels at 140mph just before the brake run).
Intamin's brakes work on the basis of eddy currents. A braking force is possible when a electric current is passed through the electromagnets on either side of the track. The movement of metal on the side of the train through the magnetic field of the electromagnets creates eddy currents in the discs. These eddy currents generate an opposing magnetic field, which then resists the forward motion of the train, providing braking force which is incredibly smooth as a computer controls the strength of the electromagnetic fields which then controls the train's deceleration.
Intamin also use hydraulics in their launch system. They have patented this because it is what propels the trains to extreme speeds very quickly. This acceleration creates the thrill the riders are wanting to experience. This hydraulic motor enables the train to reach high speeds in very short times. For example, Stealth at Thorpe Park reaches 80mph in 1.9 seconds producing 4Gs.
On the right is a diagram of a hydraulic launch system. The system begins with the large tank filled with compressed nitrogen gas and some hydraulic fluid. Formula Rossa in Ferrari World has ten of these tanks. [The picture below is of one of these tanks.]
The horizontal tanks pressurizes the nitrogen gas to 290 bar. The device beneath the tank opens a number of valves once the nitrogen gas reaches its desired pressure. The fluid is propelled to the motors that power the large drum and winch, pictured underneath the track. This winch pulls on the catch car by steel cables, pictured directly underneath the train, and the train is propelled down the track at incredible speeds with the most incredible acceleration.
These applications have not found widespread use elsewhere. However, the brake systems are now used on modern trains so the braking can be smoother and also in a shorter distance than conventional friction brakes. The hydraulic launch principle is used on aircraft carriers to launch planes that wont have enough runway to launch normally. On some aircraft carriers, they use diesel engines (pneumatic launches) instead of hydraulics which, although less powerful, is more cost-effective.
The basic principle of the hydraulic launch can also be used in regenerative braking. A good example of the use of regenerative braking is in street cleaning and refuse collection vehicles. This is because of the constant stop-start nature of the vehicle. As the truck starts to slow down, its drive shaft starts to slow down but still spins. This is wasted energy so instead of wasting it, the drive shaft turns a motor which compresses nitrogen gas to increase pressure. The high pressure gas is stored in accumulators and when the vehicle starts again, the pressure is released. This powers a motor which spins the drive-shaft helping the initial inertia to be overcome. As a result, less fuel is used to start the truck, so saving fuel and, in turn, money.
In summary, the above shows how an engineering solution for a specific problem can be used in different applications.