PASCO PS-2141 User Manual
Force Platform
PS-2141
Instruction Manual
012-09118B
Included Equipment Part Number
Force Platform PS-2141
Required Equipment
PASPORT Interface
Optional Equipment
Handle Set PS-2548
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Compatible PASPORT interfaces include the Powerlink (PS-2001), Xplorer GLX (PS-2002), USB Link
(PS-2100), and others. See the PASCO catalog, visit www.pasco.com, or contact PASCO tech support for
more information. Xplorer (PS-2000) with firmware version 1.14 or earlier is compatible in computer-based
(non-logging) mode.
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See PASCO catalog or www.pasco.com
Introduction
The PASPORT Force Platform, used with a PASPORT interface, continuously measures force (up to 4400 N or
1000 pounds) applied by a person or object. You can use the Force Platform to measure the static weight of a person standing on it, or the dynamic vertical force involved in moving and jumping. It has the measurement range
and strength to accommodate people of all sizes and the sensitivity to measure smaller forces such as the weight
of a ball. Put the platform on the floor or tabletop to measure vertical force, or mount it on a wall to measure horizontal force. With the optional handle set, you can use the platform to measure both “pulling” and “pushing”
force.
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Force Platform How It Works
How It Works
When an object is placed on the Force Platform, it applies a force normal to the platform'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 platform 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 making 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.
Hang the Force Platform using side tabs
Turn feet to level Force Platform
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 platforms together. Note that the platform measures only the component of force normal to the surface.
Optional handles
attached to bottom of
Force Platform
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.
Tare button
Using the Force Platform with DataStudio
If you are using a computer, start DataStudio. Click the Start button to begin data collection. By default, the platform collects data at 10 samples per second and displays it
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Model No. PS-2141 Safety
in units of newtons (N). You can change these settings in the Experiment Setup window. (Click the Setup button to open the window.) In the Setup window you can also
make the separate force measurement of each beam visible. For more instructions on
using DataStudio, press F1 to open DataStudio's on-line help.
Using the Force Platform with the Xplorer GLX
If you are using an Xplorer GLX without a computer, press to start data collection. By default, the platform collects data at 10 samples per second and displays it in
units of newtons (N). You can change these settings in the Sensors screen. (From the
Home screen, press to open the Sensors screen.) In the Sensors screen you can
also make the separate force measurement of each beam visible. For more instructions on using the Xplorer GLX, refer to the GLX Users' Guide.
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Safety
Teachers: The Force Platform is designed for use by students under the supervision of a
teacher. Ensure that all users understand and follow these guidelines when jumping or stepping on the platform.
• Do not stand on or jump off tables, chairs, or other inappropriate objects.
• Before you jump or step on the platform, be certain that it will not skid or move
and that you will land with your foot or feet entirely on the platform, not hanging
over the edge.
• Use the platform away from objects that may interfere with your movements or
injure you if you fall.
• Follow all other safety rules and guidelines that apply to you.
Suggested Activities
Hang Time
Stand on the platform and jump vertically. Look at a graph of
force versus time to determine your “hang time,” or how much
time you spend in the air. Is you hang time related to how high
you jump? What other factor affect hang time?
For more precise time measurements, use a higher sampling
rate.
Vertical Impulse
Motion Sensor
Use a motion sensor (PS-2103) to measure the position and
velocity of the top your head as you jump on the platform.
What is your measured vertical velocity at the moment your
feet leave the platform? If you assume that you are a point
mass, does this velocity correspond with your measured hang
time? Why not?
Stand on the platform and press the tare button. Bend your
knees and jump with one smooth motion. The area under the
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