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SS25LA
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Updated: 8.12.2013
SS25LA HAND DYNAMOMETER
Use the hand dynamometer to measure grip force—use in isolation
or combine with EMG recordings for in-depth studies of muscular
activity. The lightweight, ergonomically designed transducer
provides direct readings in kilograms or pounds. The simple
calibration procedure makes this device easy to use for precise force
measurements, and the isometric design improves experiment
repeatability and accuracy. The SS25LA is a basic unit, designed for
student lessons; it can also be used in the MRI, with proper module
setup, since it employs plastics in the spring constant.
The highest performance dynamometer is TSD121C, which employs
a four terminal, laser-trimmed, wheatstone bridge built onto
metal elements.
Hardware Setup
Connect the SS25LA Simple Sensor to a CH input on the front panel of an MP3X unit.
Proper grip
: Place the palm across the shorter bar and wrap fingers to center the force.
Scaling — Software Setup for the MP3X
1)
Select
Set Up Channels
under the MP3X menu and enable
one analog channel.
2)
Select the desired
Clench Force
Preset (kg or lbs, the example to the
right is shown in units of kg.)
3)
Click on the
Setup
button.
4)
Click on the
Scaling
button to activate a dialog box similar to the one
shown at right.
5)
In the
Map value
column, note the default scaling of “0” for
Cal2
and
“100” for
Cal1
. These represent 0 and 100 kilograms, respectively.
6)
Place the SS25LA on a flat surface.
7)
Click the
Cal2
button to obtain an initial calibration reading. A value similar to the above example “0.7556”
will appear.
8)
To obtain the
Cal1
input value, add the
Cal2
input value to the default
Cal1
3.5 mV per 100 kg value.
(In this example, this value would be 0.7556 mV + 3.5 mV = 4.2556 mV.)
NOTE:
The above instructions are for BSL 4 and higher. In
BSL 3.7.7 and earlier, placement of the CAL1 and
CAL2 scale values are reversed.
Calibration Confirmation
a)
Click “Start” to begin data acquisition.
b)
Place the SS25LA on a flat surface and then place a known
weight on the uppermost portion of the grip.
c)
Review the data to confirm that the known weight is reflected
accurately in the data (sample at right).
d)
Adjust the Scaling parameters and repeat steps a-c as necessary.
HARDWARE GUIDE
