The Magnetic Sensing Enhanced Proximity
Tool allows the user to select several types of motion for each of the magnet options.
Hinge motion, rotation, linear displacement, and joystick functions are all available
with customizable user inputs. Additionally, for a quick approximation, the field
produced by each magnet type may be checked at individual static positions.
Figure 2-1 Menu Top-Level
The general flow
when defining a simulation follows this process:
Define the Magnet:
Select the shape from the
Magnet Shape drop-down and set the desired number of poles if required.
Fields should auto-populate in the Magnet Geometry section labeled with the
required magnet dimensions.
Select the material type from
the Magnet Material drop-down. This populates a list of common material
grades that can be selected from the Material Grade drop-down. If the
desired grade is not shown, select Custom.
Most magnetic materials have
a specified range for acceptable values of Br (Remanence). Select High,
Typical, or Low from the radio buttons, and the tool will auto-populate the
Remanence value expected at 20°C. If this does not match exactly the value
needed your magnet, you may manually enter a value and over-ride the
preset.
Set the operating
temperature. Magnetic materials have a typical temperature coefficient that
describes the changes in magnetic strength of the material as temperature
varies through most normal operating conditions. This tool assumes a
constant coefficient across all temperatures and does not consider changes
in behavior at extreme temperature.
Enter the dimensions of the
magnet as required in each field of Magnet Geometry.
Define the Magnet Alignment:
The starting position of the
magnet may be set using the X Position, Y Position, and Z Position fields in
magnet alignment. Each value is relative to the center of the magnet. Linear
displacement occurs smoothly from the start position to the end position
while maintaining magnet orientation.
The orientation of the magnet
may also be adjusted using X Angle, Y Angle, and Z Angle. These rotations
will occur about the magnet center and can be used to align the magnet in
the correct direction. The rotation operations occur in XYZ order.
Define Magnet Travel:
The Magnet Travel section of
the user input window updates based on the type of motion for each function.
More detailed descriptions for this step may be found in these sections:
Define Sensor Alignment - The
magnetic field observed at any point may be selected by defining a sensor position
and alignment.
Set the absolute X Position,
Y Position, and Z Position.
This revision of
the tool does not inhibit placing the sensor within the magnet
and only represents sensors as an infinitesimal point. It is
the user's responsibility to match this location to the target
location of the sensing element within the package and to avoid
mechanical conflict.
Set the orientation of the
sensor. The sensor can be rotated by any set of angles in XYZ order and the
displayed simulation results will match this alignment. To help visualize
the sensor alignment to the magnet, a coordinate cross-hair is shown
reflecting the final sensor rotation.
Define simulation resolution:
Enter the step size to
simulate. Finer resolution simulations take longer to complete, but provide
the best overall detail. If the total range of motion cannot be divided
evenly, the tool adjusts the size of the final incremental step to the match
the remainder.
Click "Start Simulation" to generate
plots of Magnetic Fields observed at the sensor location.
If desired, proceed to select
a magnetic sensor following the steps in Device Emulation.
To change functions, click
"Return to Function Select".