The Cart Picket Fence can be used with a photogate to measure distance, velocity and acceleration vs. time.
Cart Picket Fence (PF-CART)

Using a Vernier (BTD) Photogate
Photogate (VPG-BTD)

With Logger Pro 3:
1) Connect the photogate.
2) Choose your interface from the Setup Sensors list in the Sensors menu.
3) Click on the image of the photogate, and choose Set Distance or Length.
4) Select Cart Picket Fence from the dropdown list.

With LabQuest App:
1) Connect the photogate.
2) Choose Data Collection from the Sensors menu, or tap the box with the Mode settings.
3) Photogate timing and Motion should already be set as the mode and photogate mode.
4) Select “Cart Picket Fence” from the options.
5) Set the LabQuest to stop data collection after 26 events, if desired.

With Graphical Analysis 4:
1) Connect the photogate.
2) Click or tap Mode.
3) Linear Motion Photogate Timing should already be set as the mode and measurement.
4) Select “Cart Picket Fence” from the Object dropdown list.
5) Modify the “End data collection” option if desired.

Using a Go Direct Photogate
Go Direct® Photogate (GDX-VPG)

With LabQuest App (not supported with original LabQuest):
1) Connect the photogate.
2) Tap the Velocity sensor meter, then tap Sensor Channels….
3) Change the default sensor channel setup so that Gate 1 – Gate State is the only channel selected.
4) Tap OK.
5) Choose Data Collection from the Sensors menu, or tap the box with the Mode settings.
6) Photogate timing and Motion should already be set as the mode and photogate mode.
7) Select “Cart Picket Fence” from the options.
8) Set the LabQuest to stop data collection after 26 events, if desired.

With Graphical Analysis 4:
1) Connect the photogate.
2) From the Sensors Setup menu, select SENSOR CHANNELS.
3) Change the default sensor channel setup so that Gate 1 – Gate State is the only channel selected.
4) Tap DONE.
5) Click or tap Mode.
6) Photogate Timing – Linear Motion should already be set as the mode and measurement.
7) Select “Cart Picket Fence” from the Object dropdown list.
8) Modify the “End data collection” option if desired.

See also:
How do I set up Vernier Photogates (VPG-BTD) for data collection with Logger Pro 3?
How do I set up Vernier Photogates (VPG-BTD) for data collection using LabQuest App?
How do I set up Vernier Photogates (VPG-BTD) for data collection using Graphical Analysis 4?
How do I set up a Go Direct Photogate to collect data using LabQuest App?
How do I set up a Go Direct Photogate to collect data using Graphical Analysis 4?