Actuators

Best Solution has experience in the design and modelling of a wide range of electromagnetic actuators including torque motors, optical scanning motors, a.c. and d.c. solenoids, permanent magnet linear motors and loudspeaker motors.

We are experienced in classical magnetic circuit design methods, finite element optimisation, and dynamic modelling. We can provide detailed performance predictions based on these techniques, as well as approximate transfer function representations for those interested in incorporating actuators in closed loop control applications.

For devices which are highly non-linear, for example conventional d.c. or a.c. solenoids, we can provide a block diagram representation for use in any of the commercial graphical simulation packages such as Matlab/Simulink, or VisSim. An example of a dynamic model of a solenoid implemented in Visual Solutions Inc VisSim is shown below. The model uses a simple magnetic circuit approach and assumes linear materials. It therefore has some limitations, but within reasonable boundaries on geometry and material performance, it can give useful guidance on the achievable response times for a solenoid driven by a voltage step input.

The physical laws governing the behaviour of a d.c. solenoid can be expressed in block diagram form (see below). Using VisSim orMatlab/Simulink it is a fairly easy process to convert this into a useable dynamic model. The model serves a useful purpose for "first pass" design, and if required, an accurate response can be obtained using a 2d or 3d transient finite element model.