GONIOMETER ADAPTER
Sensor Type
A Goniometer or Torsiometer set up comprises two parts, the sensor and the adapter. Two types
of Goniometer Adaptor are available; one is labeled Goniometer/Torsiometer Adapter and is for
interfacing to the Penny & Giles style sensor, the other is for interfacing with the Flex point bend
sensor. Both are treated the same with respect to operation. Contact TTL or our authorized
dealers for information on purchasing the sensors.
Operating Principle
A Goniometer/Torsiometer sensor can be sensitive to movement in a number of directions X axis,
Y axis and Rotation for a Torsiometer. Goniometers are available in a number of sizes with
measurement in up to two axes. Each axis requires a separate adapter. When connected to a
person or articulated object they sense changes in angle of one end of the sensor in relation to
the other end. The sensor plugs into the adapter which in turn plugs into the encoder.
Measurement Unit
A goniometer sensor converts its position to a raw value, as the position changes the value
corresponding to that position changes with it. Most goniometers have a specified minimum and
maximum deflection. This raw value can be transformed into a meaningful calibrated value in
the software by using the linear transform virtual channel. This linear transform takes the
minimum and maximum raw value and converts it to the min-max output values corresponding
to the positions (e.g. -119 to 72 becomes 0 to 180 Degrees.)
To calibrate the sensors, connect the hardware and open the goniometer calibration screen then
start a recording. Manipulate the goniometer to its maximum and minimum specified deflection.
Record the max and min values. Stop the session and move to the channel set that is going to
be used to record data, edit the virtual channel set and select the virtual channel relating to the
axis that you are calibrating. Manually enter the input Min and Max values and the
corresponding output min and max values. It is also possible to enter the units of measure
which will appear in generated reports.
ProComp Infiniti Hardware Manual
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