PASCO ME-1240, ME-1241 Reference Manual

Wireless Smart Cart

®

Bluetooth Status LED

Battery Status LED

Bumper
Attachment

Hook
Attachment

Magnetic Bumper

Power: Rechargeable Battery

OR

USB Cable

Micro USB Cable

Connection:

Device ID

Micro USB Port

Plunger Release

Velcro® Tab

Velcro® Tab

ON/OFF Icon

USB Icon

Accelerometer Position

M5 Threaded Hole

ON/OFF Button

Accessory Tray

Attachment
Point

Built-in Wheel Encoder
for Position and Velocity

ME-1240 (Red) / ME-1241 (Blue)

Reference Guide

013-14727B

Hardware

Included Equipment Part Number

Wireless Smart Cart

Magnetic Bumper

Hook Attachment

Bumper Attachment

Micro USB Cable (1 meter)

Required

Software For Information

PASCO Data Collection Software www.pasco.com

See the PASCO Web page at

800-772-8700 (US) [phone]
www.pasco.com [e-mail]

www.pasco.com/software

ME-1240 or ME-1241

ME-9885A

for help in selecting the right PASCO software and to
check the latest versions.

Introduction

The Wireless Smart Cart is a combination wireless
USB device that connects to a computer or tablet
through Bluetooth® (version 4.2 or later), or to a
computer or USB charger with a micro USB cable
(included). The Smart Cart has a durable ABS body, a
three-position plunger, and nearly frictionless wheels. It
includes built-in sensors that measure force, position,
velocity, and three degrees of freedom in acceleration.
The Smart Cart also includes a gyroscope-type sensing
element that can measure rotational motion. The Smart
Cart can make its measurements on or off a dynamics
track and transmit them wirelessly. For easy identifica­tion, the Smart Cart is available in red or blue.

and

®

Wireless Smart Cart ME- 1240 (Red) / ME-1241 (Blue)

Three-position Plunger

Hook

Attachment

+X

+Y

+Z

Acceleration Sensor

Position

Attachment

point

Attachment point

The Smart Cart is designed by PASCO
in California and assembled in China.

The accessory tray on the top of the Smart Cart can hold
any of the accessories designed for a PASCO cart. The
Smart Cart dimensions are the same as other PASCO
carts and can be used with any PASCO track. The
Smart Cart can be stacked with any PASCO cart and its
mass is approximately 0.250 kilograms (about 250
grams). It has attachment points on the top and bottom
of both ends, and Velcro® tabs for inelastic collisions on
one end. The Magnetic Bumper, Bumper Attachment,
and Hook Attachment fit into the threaded hole in the
end of the Smart Cart opposite to the tabs.

The built-in sensors measure force in the range between

-100 newtons (N) and +100 N, acceleration in the range
between -16g and +16g (g = ±9.8 m/s

2

), and angular
rotation rate up to ±245 degrees per second (dps). It
measures force as a push or pull along its X axis and
measures acceleration in three dimensions (X, Y, and
Z). The PASCO Data Collection Software can also show
the resultant acceleration. The encoder wheels on the
Smart Cart measure motion to a maximum of 3.0 meters
per second with a resolution of 0.2 millimeters (mm).
The positive direction of motion is the same as the
X-axis in the graphic that represents the acceleration
sensor’s position

Data Collection Software

PASCO Capstone SPARKvue

• Mac OS X • Mac OS X

• Windows • Windows

•iOS

•Android

• Chromebook

See the PASCO Web page at

www.pasco.com/software

for help in selecting the right PASCO software and to
check the latest versions.

Software Help

.

The Smart Cart is designed to optimize the battery
usage time. Since each Smart Cart has a unique Device
ID number, more than one can be connected to a
computer or tablet at the same time.

See the SPARKvue Help or PASCO Capstone Help for
information about collecting, displaying, and analyzing
data.

• In SPARKvue, select the HELP button ( ) in any
screen including the Home Screen.

• In PASCO Capstone, select PASCO Capstone Help
from the Help menu, or press F1.

Compatibility

Check the PASCO Web page at

www.pasco.com/wireless

for the latest information on Bluetooth SMART
compatibility.

Platform Bluetooth SMART Compatibility

iOS iPad 3 and later

iPhone 4S and later
iPod touch 5 and later

SPARK Element All models

Android Android 4.3 and later

Chromebook Chrome OS (requires PS-3500 Adapter*)

Mac OS X Models introduced July 2011 or later*

Windows Windows 7 and later (requires PS-3500 Adapter*)

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®

Set Up the Software ME-1240 (Red) / ME-1241 (Blue)

Micro USB

Port

Micro USB Cable

USB

Port

+See Appendix A for more information about the PS-3500 Adapter and
Mac OS X models.

Initial Step: Charge the Battery

• Connect the Cable: Use the Micro USB Cable to
connect the micro USB port on the Wireless Smart
Cart to a USB port or USB charger such as the
PASCO PS-3501 USB Charging Station. Charging
begins automatically. The charger circuit inside the
Smart Cart turns itself off when the unit is fully
charged. The battery status LED will shine yellow as
the battery is charging, and will shine green when
the battery is charged. The battery is partially
charged at the factory. Initial charging time may be
three hours or longer depending on the power
source and the condition of the battery.

ON/OFF Information

For a wireless Bluetooth connection:

Bluetooth LED Status Battery LED Status

Red blink Ready to pair Red blink Low power

Green blink Connected

For a micro USB cable connection to a USB

Bluetooth LED Status Battery LED Status

OFF -- Yellow ON Charging

OFF -- Green ON Charged

For a micro USB cable connection to a USB

Bluetooth LED Status Battery LED Status

Red blink Ready to pair Yellow ON Charging

Green blink Connected Green ON Charged

port

:

charger

Check the PASCO Web page at:

www.pasco.com/software

for help in selecting the right software and to check the
latest software version.

:

To turn the Smart Cart on, press and hold the ON button
for a moment until a status LED starts blinking. To turn
the Smart Cart off, press and hold the ON button for a
moment until the status LEDs stop blinking. The
Wireless Smart Cart puts itself to sleep after several
minutes of inactivity if not connected and a much longer
time of inactivity if connected.

LED Information

The Bluetooth and the Battery Status LEDs operate as
follows depending on the type of connection:

Set Up the Software

SPARKvue

See the SPARKvue Help for information about setting up
the software:

• In SPARKvue, select the HELP button ( ) in any
screen, such as the Home Screen.

Connecting the Wireless Smart Cart to a Tablet or a
Computer via Bluetooth

• For SPARKvue, select the Bluetooth icon ( ) to
open the Wireless Devices list. In the Wireless
Devices list, the devices are ordered by proximity to
the tablet or computer. Select the Smart Cart that
matches the XXX-XXX number found on the Smart
Cart. Select Done. A list of measurements appears
under the Smart Cart in the Home Screen.

Connecting the Wireless Smart Cart to a Computer with
the Micro USB Cable

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• Connect the micro end of the included Micro USB
Cable into the micro USB port on the end of the
Smart Cart. Connect the other end of the Micro USB
Cable to a USB port on the computer, or into a
powered USB hub connected to the computer.

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®

Wireless Smart Cart ME- 1240 (Red) / ME-1241 (Blue)

Bumper

Attachment

Hook

Attachment

Magnetic

Bumper

Metal

Post

Zero (Tare) the Smart Cart

At the beginning of an experiment, the measurement
from the built-in force and acceleration sensors may not
be zero when the force or acceleration is actually zero.
This is a normal behavior that is corrected when you
zero (or tare) the sensor using the PASCO Data
Collection Software. See Appendix B for information
about setting the built-in sensors to zero.

Collect Data

• In the SPARKvue Home Screen, select a
measurement from the list under the sensor’s name.
A graph of the measurement versus time opens.

• In SPARKvue, select the Start button ( ) to begin
collecting data.

PASCO Capstone

See the PASCO Capstone Help for information about
setting up the software:

Collect Data

• In PASCO Capstone, select a display in the main
window or from the Display palette. In the display,
use the <Select Measurement> menu to pick a
measurement to be shown.

•Select Record to begin collecting data.

Troubleshooting the Wireless Smart Cart

• If the Wireless Smart Cart loses Bluetooth
connection and will not reconnect, try cycling the ON
button. Press and briefly
status LEDs blink in sequence, and then release the
button. Start the Smart Cart in the usual way.

• If the Smart Cart stops communicating with the
computer software or tablet application, try
restarting the software or application. If the problem
remains, press and hold the ON button for 10
seconds and then release. Start the Smart Cart in
the usual way.

hold

the button until the

• In PASCO Capstone, select PASCO Capstone Help
from the Help menu, or press F1.

Connecting the Wireless Smart Cart to a Tablet or a
Computer via Bluetooth

• For PASCO Capstone, select Hardware Setup in the
Tools palette. The devices in the list are ordered by
proximity to the tablet or computer. Select the Smart
Cart with the address that matches the XXX-XXX
Device ID number on the Smart Cart.

Connecting the Wireless Smart Cart to a Computer with
the Micro USB Cable

• Connect the micro end of the included Micro USB
Cable into the micro USB port on the side of the
Smart Cart. Connect the other end of the Micro USB
Cable to a USB port on the computer, or into a
powered USB hub connected to the computer.

Zero (Tare) the Force Sensor

At the beginning of an experiment, the measurement
from the built-in force and acceleration sensors may not
be zero when the force or acceleration is actually zero.
This is a normal behavior that is corrected when you
zero (or tare) the sensor using the PASCO Data
Collection Software. See Appendix B for information
about how to set the built-in sensors to zero.

• Turn Bluetooth off and then turn it back on. Retry.

Set Up the Hardware

Connecting Bumper and Hook Attachments

Screw the bumper or hook attachment into the threaded
hole on the front end of the Smart Cart as shown.

The Magnetic Bumper
has a metal post that
fits in the small hole to
the side of the threaded
hole in the front end of
the Smart Cart. The
post ensures that the
Magnetic Bumper is
mounted in the correct
orientation.

4

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®

Set Up the Hardware ME-1240 (Red) / ME-1241 (Blue)

+X

+Y

+Z

+1.0 g in X

-1.0 g in X

+1.0 g in Y

-1.0 g in Y

+1.0 g in Z

-1.0 g in Z

Direction of Acceleration Sensitivity

The acceleration sensing unit inside the Smart Cart is
oriented so that the lines of greatest sensitivity follow the
three X-Y-Z arrows indicating the direction of
acceleration.

In this orientation, the X-axis direction is ‘along’ the long
axis of the Smart Cart, the Y-axis direction is
‘perpendicular’ relative to the top of the Smart Cart. The
Z-axis direction is ‘perpendicular’ to the long axis of the
Smart Cart and parallel relative to the top of the cart.

If the Smart Cart is held so that the accessory tray is on
top and horizontal, the Acceleration Y-axis reading is 1.0
g. If the Smart Cart is turned so that the accessory tray is
horizontal and on the bottom, the Acceleration Y-Axis
reading is -1.0 g.

If the Smart Cart is placed so its side so that the Z-axis
on the top of the cart is pointing upward, the
Acceleration Z-axis reading is 1.0 g. If the Smart Cart is
placed on its other side so the Z-axis is pointing down­ward, the Acceleration Z-axis reading is -1.0 g.

Test the Smart Cart’s Output Using Earth’s Gravity

Start the PASCO Data Collection Software. If the Smart
Cart is held so that the X-axis on the top of the Smart
Cart is vertical and pointing upward, the Acceleration
X-axis reading is +1.0 g. If the Smart Cart is turned so
the X-axis is vertical but pointing downward, the
Acceleration X-axis reading is -1.0 g (where “g”
represents the acceleration due to gravity).

Smart Cart Accessories

For help in deciding on accessories for the Smart Cart,
go to

www.pasco.com/products

and select Carts and Tracks under Product Families.

Accessories Include:

• Fan Accessory

• Ballistic Cart Accessory

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®

Wireless Smart Cart ME- 1240 (Red) / ME-1241 (Blue)

Fan

Accessory

Rails

ON/OFF

Switch

• PAScar Cart Masses

• Compact Cart Mass

• IDS Spring Kit

• Dynamics Track End Stop (2 pack)

• Dynamics Track Feet (pair)

• Discover Collision Bracket

• Mechanical Oscillator/Driver

• PAStrack

• Curved PAStrack

• PAStrack Inclined Plane Accessory

• Classic Dynamics Tracks (1.2 and 2.2 m)

Systems

• Smart Cart Dynamics System 1.2 m

• Smart Cart Dynamics System 2.2 m

Mounting the Fan Accessory on the Smart Cart

• Snap the sides of the Fan Accessory over the rails
on the accessory tray of the Smart Cart.

About the Battery

The Smart Cart’s battery is partially charged at the
factory. If the battery status LED blinks red, use the
micro USB cable to connect the sensor to a USB port or
a USB charger.

Battery Usage

Battery life is very important to making the product
simple and always ready to use, so all of the PASCO
wireless products are designed for long battery life. For
example, the Smart Cart turns itself off after a few
minutes of inactivity to conserve battery life.

The battery life between charges for the Smart Cart
varies depending on the sampling rate. The battery life
ranges between eleven hours for high sample rates to
more than 70 hours for low sample rates.

6

In typical classroom/lab use, this would translate to a
battery life between charges ranging from one to four
weeks or more, because full-day continuous sampling
would be unusual. Even in the most extreme case with a
high sample rate, the Smart Cart battery would support a
full day of use before needing to recharge.

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®

Technical Support ME- 1240 (Red) / ME-1241 (Blue)

Maximizing Battery Life

One of the factors that affects battery life is the storage
temperature. Therefore, avoid storing the Smart Cart in
very cold or very hot environments.

Troubleshooting

If the Battery Status LED blinks red, use the micro USB
cable to connect the Smart Cart to a USB port or a USB
charger.

If the Smart Cart battery will not charge, it may need to
be replaced. Contact Technical Support for information
about battery replacement.

Suggested Experiments

Practically any experiment that has a force, acceleration,
linear motion, or rotational motion measurement can be
done with the ME-1240 or ME-1241 Smart Cart. See the
PASCO Web site at

www.pasco.com/products/lab-manuals

Item: Acceleration Value

Range

Maximum sampling rate 500 samples/second

±16g (g = 9.8 m/s

Bluetooth distance

30 m (unobstructed)

Technical Support

For assistance with any PASCO product, contact
PASCO at:

Address: PASCO scientific

10101 Foothills Blvd.
Roseville, CA 95747-7100

Phone: [phone] (worldwide)

8700-772-8700 (U.S.)

Web:

Email: [e-mail]

www.pasco.com/support

2

)

for more information about experiments.

Calibrating the Sensors

The Smart Cart is factory calibrated. Further calibration
is not necessary, especially if you are measuring a
change in force, acceleration, or motion rather than
absolute values. However, it is possible to calibrate the
sensors. For detailed information, see Appendix C.

Specifications

Item: Force Value

Range ±100 newtons (N)

Resolution 0.1 N

Accuracy ±1%

Maximum sampling rate 500 samples/second

Burst mode sampling rate* 5000 Hz (for 1 second)

*During burst mode, other sensors will be turned off.

Item: Position Val ue

Resolution

Item: Velocity Val ue

±0.2 mm

The Reference Guide will be updated periodically. For
the latest revision of this Reference Guide, visit the
PASCO Web site at

www.pasco.com/manuals

and enter the product number, PS-3202, in the text
window.

Replacement Parts

For information about replacement parts, contact
Technical Support:

USB Cable, Micro-to-USB A
Hook Attachment
Bumper Attachment
Magnetic Bumper (ME-9885A)

Limited Warranty
For a description of the product warranty, see the PASCO catalog. For
more information visit www.pasco.com/legal

Copyright
This PASCO scientific
reserved. Permission is granted to non-profit educational institutions for
reproduction of any part of this manual, providing the reproductions are
used only in their laboratories and classrooms, and are not sold for profit.
Reproduction under any other circumstances, without the written consent
of PASCO scientific, is prohibited. V: 4/16.

Reference Guide

is copyrighted with all rights

Maximum velocity

Maximum sampling rate 100 samples/second

±3 m/s

Trademarks
PASCO, PASCO scientific, PASCO Capstone, PASPORT, and
SPARKvue are trademarks or registered trademarks of PASCO scientific,
in the United States and/or in other countries. All other brands, products,

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®

Wireless Smart Cart ME- 1240 (Red) / ME-1241 (Blue)

or service names are or may be trademarks or service marks of, and are
used to identify, products or services of their respective owners. For more
information visit www.pasco.com/legal.

FCC Statement
This Class A digital device complies with part 15 of the FCC Rules.
Operation is subject to the following two conditions: (1) This device may
not cause harmful interference, and (2) this device must accept any
interference received, including interference that may cause undesired
operation.

CE Statement
This device has been tested and found to comply with the essential
requirements and other relevant provisions of the applicable EU
Directives.

Product End of Life Disposal Instructions:
This electronic product is subject to disposal and recycling regulations that
vary by country and region. It is your responsibility to recycle your
electronic equipment per your local environmental laws and regulations to
ensure that it will be recycled in a manner that protects human health and
the environment. To find out where you can drop off your waste equipment
for recycling, please contact your local waste recycle/disposal service, or
the place where you purchased the product.

The European Union WEEE (Waste Electronic and
Electrical Equipment) symbol (to the right) and on the
product or its packaging indicates that this product
must not be disposed of in a standard waste
container.

Battery Disposal Instructions:
Batteries contain chemicals that, if released, may affect the environment
and human health. Batteries should be collected separately for recycling,
and recycled at a local hazardous material disposal location adhering to
your country and local government regulations. To find out where you can
drop off your waste battery for recycling, please contact your local waste
disposal service, or the product representative.

The Lithium Polymer (Li-Poly) rechargeable battery used in this product is
marked with the International symbols to indicate the need for the
separate collection and recycling of batteries.

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Technical Support ME- 1240 (Red) / ME-1241 (Blue)

PS-3500 USB

Bluetooth 4.0

Adapter

1

Appendix A: Compatibility

The Mac Mini and MacBook Air were updated with

Bluetooth SMART support in 2011. The MacBook Pro

Check the PASCO Web page at

was updated in 2012. The Mac Pro that debuted in
December 2013 has Bluetooth SMART support.

www.pasco.com/wireless

Exception: Please contact PASCO Technical Support for

for the latest information on Bluetooth SMART
compatibility.

further instructions before you upgrade to El Capitan
(Mac OS X 10.11.x), if you have a Macintosh with LMP
version “0x4” that requires the PS-3500 USB Bluetooth

Platform Bluetooth SMART Compatibility

iOS iPad 3 and later

iPhone 4S and later
iPod touch 5 and later

SPARK Element All models

Android Android 4.3 and later

Chromebook Chrome OS (requires PS-3500 Adapter*)

Mac OS X

Windows Windows 7 and later (requires PS-3500 Adapter*)

1

Models introduced July 2011 or later

4.0 Adapter.

What is Bluetooth SMART

®

?

Bluetooth SMART (also known as Bluetooth Low Energy
or Version 4.0 of the Bluetooth specification) is the latest
protocol of the proprietary open wireless technology
standard created by telecoms vendor Ericsson in 1994.
It is the power- and application-friendly version of
Bluetooth that was built for the Internet of Things (IoT).

Appendix B: Zero (tare) the Sensors

*The PS-3500 USB Bluetooth 4.0
Adapter, when connected to a USB
port, allows up to three Bluetooth
SMART devices, such as this PASCO
wireless device, to connect to Windows
computers, Chromebooks, and older
Macintosh computers.

Note: The PS-3500 USB Bluetooth 4,0
Adapter is the only adapter we can currently
recommend. Many other Bluetooth 4.0 adapters are
available but this adapter has a specific design that
enables in-app pairing of Bluetooth SMART sensors.

1

To check the Mac computer’s Bluetooth compatibility,

do the following:

• Click the

 (Apple) Menu.

Zero (Tare) the Smart Cart

At the beginning of an experiment, the measurement
from the built-in force and acceleration sensors may not
be zero when the force or acceleration is actually zero.
This is a normal behavior that is corrected when you
zero (or tare) the sensor using the PASCO Data
Collection Software.

See the SPARKvue Help for up-to-date information
about zeroing the Smart Cart:

• In SPARKvue, select the HELP button ( ) in any
screen, such as the Home Screen.

In SPARKvue, the process for setting the Wireless
Smart Cart to zero starts in the Home Screen ( ).

• Select

• Click the

• Click the

• Select
underneath

About This Mac

More Info

... button.

System Report

Bluetooth

from the sidebar on the left,

Hardware

... button.

.

• Scan down the list of information until you find “LMP
Version”.

• If your Mac is equipped with Bluetooth SMART, the
LMP Version will show 0x6. (Anything lower than
0x6 means an older version of Bluetooth. Your
device will need the PS-3500 USB Bluetooth 4.0
Adapter.)

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1. To zero the force sensor, start by selecting Force in
the Home Screen to open a Graph display of Force
versus Time.

2. In the Graph display, select the Experiment Tools
( ) icon to open the Experiment Tools window.

3. In the Experiment Tools window, select Configure
Sensor in the menu to open the Sensor
Configuration window.

4. In the Sensor Configuration window, select the Edit
Sensor Properties button to open the Edit Sensor
Properties menu.

5. The Edit Sensor Properties menu shows two
choices:

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®

Wireless Smart Cart ME- 1240 (Red) / ME-1241 (Blue)

Zero

button

Common Rate menu Default sample rate

Properties

icon

C.

Smart Cart Force Sensor Properties Window

• Smart Cart Force Sensor

• Smart Cart Acceleration Sensor.

6. Select the Smart Cart Force Sensor choice from the
menu to open the Edit Sensor Properties window.

7. The Edit Sensor Properties window offers two
choices under Tare Sensor:

• Zero Sensor Automatically On Start:

• Zero Sensor Now

8. In the Edit Sensor Properties window, select Zero
Sensor Automatically On Start if you want the
sensor to be set to zero every time that data
collection begins. Select Zero Sensor Now to set the
sensor to zero manually.

9. Select OK at the bottom of the window to return to
the Graph display.

To zero the acceleration for the Acceleration Sensor,
return to the Home Screen ( ). (NOTE: There may
be a message about saving your data.)

1. To zero the Smart Cart Acceleration Sensor, start by
selecting any of the choices for acceleration in the
Home Screen to open a Graph display of
Acceleration versus Time.

2.

Repeat the process to zero the Smart Cart
Acceleration Sensor if needed.

Another option is to select a choice in the sensor’s
Properties palette:

1. Click Hardware Setup in the Tools palette to open
the Hardware Setup window.

2. Click the Properties icon for the Smart Cart Force
Sensor to open the Properties window.

3. In the Properties window, select one of the three
choices and then click OK at the bottom to close the
window.

2. In the Graph display, select the Experiment Tools
( ) icon to open the Experiment Tools window.

3. Follow the same procedure that you used for setting
the force measurement to zero.

See the PASCO Capstone Help for up-to-date
information about zeroing the Smart Cart:

• In PASCO Capstone, select PASCO Capstone Help
from the Help menu, or press F1.

In PASCO Capstone, there are options for setting the
Wireless Force Sensor to zero.

One option is to use the Zero button:

1. Select Smart Cart Force Sensor from the Common
Rate menu and then click the Zero button. This will
set the sensor reading to zero.

• Zero Sensor Measurements at Start – Zero the
Wireless Force Sensor at the start of data collection.

• Zero Sensor Now – Works the same as the Zero
button.

• Remove Sensor Zero Offset – Undo. Return the
Wireless Force Sensor to its previous state.

4. Repeat the process for the Smart Cart Acceleration
Sensor if needed.

Appendix C: Calibration

The Smart Cart is factory calibrated, so calibration is not
necessary, especially if you are measuring a change in
force rather than absolute force values. However, it is
possible to calibrate the sensor.

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Technical Support ME- 1240 (Red) / ME-1241 (Blue)

Prepare for Calibration

Calibration will need a 1 kilogram mass, the hook
attachment, string, and a horizontally mounted support
rod to hold the Smart Cart. The Smart Cart will need to
be “connected” with a tablet or computer, and the data
collection software (for example, SPARKvue) should be
running.

Using SPARKvue Software for Calibration

See the SPARKvue Help for information about
calibrating:

• In SPARKvue, select the HELP button ( ) in any
screen, such as the Home Screen.

1. Screw the hook attachment into the Smart Cart.

2. Use string tied to the two attachment points on the
pad end of the Smart Cart to hang the cart from a
horizontal rod.

10. Under Calibration Point 1, click Read From Sensor.

• The value measured by the sensor is transferred to
the Sensor Value box.

11. Remove the 1 kilogram mass from the hook
attachment. The net force now is zero N.

12. Under Calibration Point 2, click the Standard Value
box and enter the second known force value (i.e., 0).

13. Under Calibration Point 2, click the

Read From

Sensor box.

• The second value measured by the sensor is
transferred to the Sensor Value box.

14. Click OK.

Using PASCO Capstone for Calibration

See the PASCO Capstone Help for information about
calibrating:

• In PASCO Capstone, select PASCO Capstone Help
from the Help menu, or press F1.

3. Click (or press) the Experiment Tools button ( ).

•The Experiment Tools screen opens.

4. Click Calibrate Sensor.

•The Calibrate Sensor: Select Measurement screen
opens.

5. Click the Sensor box and click the sensor to be
calibrated.

6. Click the Calibration Type box and click a calibration
type. (For this example, click “2-point”.)

7. Click Next.

•The Calibrate Sensor Enter Values screen opens.

8. Hang the 1 kilogram mass on the hook attachment.

9. The gravitational force on the mass is pulling in the
negative direction at -9.8 newtons (N). Under
Calibration Point 1, click the Standard Value box
and enter the known force value (that is, -9.8).

1. Screw the hook attachment into the Smart Cart.

2. Use string tied to the attachment points on the pad
end of the Smart Cart to hang the cart from a
horizontal rod.

3. Click Calibration ( ) in the Tools palette.

4. Choose the measurement you would like to calibrate
now: Force Measurement.

5. Click Next.

6. Choose the type of calibration you would like to
perform: Two Standards (2 point).

7. Click Next.

8. Hang the 1 kilogram mass on the hook attachment.

9. The net force on the sensor is -9.8 N. Enter the
value in the Standard Value text box.

10. When the Current Value stabilizes, click Set Current
Value to Standard Value.

11. Click Next.

12. Remove the 1 kilogram mass from the hook
attachment. The second force value is zero N.

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Wireless Smart Cart ME- 1240 (Red) / ME-1241 (Blue)

13. Enter the second known force value (i.e., 0) in the
Standard Value text box.

14. When the Current Value stabilizes, click Set Current
Value to Standard Value.

15. Click Next.

16. Click Finish.

Theory of Calibration

One of the functions of the PASCO Data Collection
Software is to take the stream of raw data from a sensor
and transform it into the calibrated data that you see in
the Graph, Table, and other displays. If you do not
calibrate a sensor yourself, the software uses a default
calibration that is loaded when the sensor is connected.

You can think of the software as taking in raw data and
outputting calibrated data. When you perform a
calibration, the software redefines the linear equation
that transforms the raw input data into the calibrated
output data. The linear function is of the form:

Raw Input = Slope x Calibrated Output + Offset

multiple similar sensors; however, for any given sensor,
the software will automatically select the most typical
calibration type as the default setting.

Two-Point

In a two-point calibration, you reset two points to define
a new line. This type of calibration affects both the slope
and the offset.

One-Point Slope

In a one-point slope calibration, you reset only one point.
The slope of the line changes so that the line intersects
the new point, while the offset (or Y-intercept) does not
change.

Or:

Calibrated Output = (Raw Input - Offset)/Slope

The function can be represented graphically as a line.

Two points, Pt 1 and Pt 2, define the line. In the
two-point calibration procedure, each point is reset by
associating a known standard value (for instance, the
temperature of ice water) with a raw input measurement
that the sensor sends out when it is in that standard. In a
one-point calibration, only one of the points is reset by
the user.

One-Point Offset

In a one-point offset calibration, you reset only one point.
The line shifts so that it intersects the new point, but its
slope does not change.

Types of Calibration

There are three types of calibration: two-point, one-point
slope, and one-point offset. Any of these calibrations can
be performed on a single sensor, or simultaneously on

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Offset calibration is usually used to make one sensor
agree with another sensor. Due to normal variation
among probes, a second probe might read consistently

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Technical Support ME- 1240 (Red) / ME-1241 (Blue)

higher than the first probe. Normally this difference
would be insignificant; however, an offset calibration can
be used to bring the sensors into closer alignment.

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