Motion Characterization

Bulk Flow Analystâ„¢ was originally designed to deal with belt conveyor transfer chutes, but as our users' needs evolved we developed moving boundaries to include modes of transport besides conveyor-like motion. Through the Bulk Flow Analyst interface, users can define several different forms of what we call "simple" motion. Simple motion is typically along a single vector or about a single axis and involves translation and/or rotation at constant speed throughout the duration of the simulation. Simple motion options include:

  • Translation Only: The boundary moves in a linear direction. Translation Only allows for 4 different speeds along this line, and is in this way unique among the other forms of simple motion. A negative speed reverses the direction.
  • Rotation Only: The boundary rotates at constant speed around an axis selected by the user. The user also defines the direction of rotation using the right-hand rule.
  • Oscillation: Components defined as "Rotation Only" can have a frequency of oscillation applied, causing the component's angular velocity to be driven sinusoidally.
  • Translation & Rotation: Motion of this type combines single-speed translation with rotation.
  • Path guided motion: Users define a path made up of linear or circular arcs in a closed loop. Components "attached" to a path follow the loop at a constant speed during the simulation. Users can also choose whether or not the components rotate as they follow the arc segments. For an example of path-guided motion, click here.
  • Vibration: Users can define motion for components such as vibrating screens or feeders. The frequency and amplitude of the vibration is constant throughout the simulation.


  • Complex Motion: Complex motion covers a variety of movements that is not constant, either in speed or direction. Using a tool we call Motion Manager, users can define individual movements along different vectors, starting, stopping, and changing direction as many times as required to meet the user's needs. Additionally, there's a built-in capability to link components so the motion of one is somewhat dependent upon another. The linked component may move in addition to the linked motion, but it must move with the component to which it is linked.