This simulation demonstrates collisions between a mechanism (the shaker) and other parts. The shaker is moved with a diagonal vibration caused by a motor which rotates a crank which pushes/pulls the container (mounted on four short rods). When the spheres fall into the container and the engine starts to increase speed, the vibration will cause the spheres to accumulate into the opposite side of the box.

Some notes about the simulation settings.

1) The engine starts with zero speed and later has a variable speed: open the property window of the motor and look into the 'Spec / Custom' panel. See how the w(t) speed CHfunction is set in SEQUENCE mode (press the button and look how the speed is defined as an increasing ramp during the first seconds of simulation, up to a fixed constant value for the rest of the time).

2) Since the simulation involves high-frequency phenomena, the integration time step has been set lower than the default. Look into the property window of the 'system' object, in 'Spec / Settings' tab.

3) The geometry of the shaker is a bit complex, for aesthetical reasons (includes bolts, holes, etc.) However, only few of these primitives are used for collision detection, otherwise the simulation would be slower (also, R3D booleans on CSG like holes etc. are not supported by the collision engine). In detail, for the boxed geometry of the 'shaker' body, only five cube primitives are used for collision, namely the floor and the four walls. For all other details, like the bolts or the engravings, we set the integer tag 'noc=1' (see property window, 'Tag' tab) to deactivate collision detection on them.

(c) DeltaKnowledge 2007