MultiJoints
We have talked a lot about prefractured objects in the previous chapters, and this type is indeed one of the main fields of application for MultiJoints. MultiJoints can be seen as dynamic connections for connecting objects. Let's take a look at a scene with a fractured, rigid body node. Shortly after the beginning of the simulation, the pieces start to break apart, because they are treated as individual nodes without any connection. In order to prevent this, the fragments have to be reconnected and this can be done with MultiJoints. Another, very common, way to use this system is the simulation of different hinges and limbs.
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It is even possible to connect rigid and soft bodies with MultiJoints.
MultiServos
Last but not least, RealFlow offers a system to equip your objects with small motors – the MultiServos. With the help of this node type you are able to turn your setups into physically correct engines. You can accelerate and decelerate your bodies, connect them through MultiJoints, and create complex machines, and accurately behaving technical devices, for example shock absorbers in cars. The behaviour of these simulations is far beyond of what is possible with traditional animation methods. Cars will be able to follow the bumps and pits of a street, MultiServo-driven cable cars cross valleys and rivers, roller coasters follow spectacular courses, and heavy Diesel trains with lots of cargo slowly leave a freight terminal.
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