PASCO PS-2141 Force Platform - Manual (Page 2)

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F o r c e P l a t f o r m H o w It W o r k s
2
How It Works
When an object is placed on the Force Platform, it applies a force normal to the plat-
form's surface; this force is the object's weight. Because the Force Platform does not
move (much), the force applied by the floor to the platform's feet increases by an
amount equal to the object’s weight. Each of the four feet is connected to a beam with
a strain gauge, through which the platform's electronics measure the force. The plat-
form calculates and outputs the sum of these four forces. Force is measured in this
way even if it is not constant, for instance, the force applied by a bouncing ball or
jumping person.
As well as the sum of the forces applied to the four beams, the platform can be set to
output the separate force measured by each beam. See below for instructions on mak-
ing these measurements visible.
Hardware Setup
On the floor
Place the Force Platform on the floor. It works best on a hard
floor, such as tile or wood, rather than carpet, which would
allow the platform to move slightly when you step on it. If the
floor is not perfectly level, adjust the platform's feet by turning
them to make the platform level and stable. The platform
should have all four feet on the floor, with nothing touching
the flat bottom surface.
On a Wall
To measure horizontal force, use the tabs on the side of the
platform to hang it from a pair of bolts or hooks on a wall.
Make sure that all four feet are in stable contact with the wall.
With the Optional Handle Set
Fasten the handles to the threaded brass inserts on the top of
the platform, or remove the feet and fasten the handles to the
bottom of the platform. With the handles, you can hold the
platform against a wall to measure horizontal pushing force. If
you have two platforms with handles (attached to the bottom),
you can demonstrate Newton's third law by pushing the plat-
forms together. Note that the platform measures only the com-
ponent of force normal to the surface.
Interface and Software Setup
Connect the platform's cable to a PASPORT interface. A green LED on the side of the
platform lights to indicate that the unit is powered and ready to take data. Press the
tare button to set the output to zero.
Using the Force Platform with DataStudio
If you are using a computer, start DataStudio. Click the Start button to begin data col-
lection. By default, the platform collects data at 10 samples per second and displays it
Optional handles
attached to bottom of
Force Platform
Turn feet to level Force Platform
Hang the Force Platform using side tabs
Tare button