Motion Sensor

Product Code: CI-6742A


PASCO’s digital ScienceWorkshop Motion Sensor II is used to measure position, velocity and acceleration. Ultrasonic pulse-ranging technology has a switch-selectable Standard Beam or Narrow Beam to reject false signals and produce cleaner data. The Motion Sensor sits firmly on a desktop or easily mounts to a rod stand or PASCO Dynamics Track.

The “Narrow Beam” setting, for distances from 15 cm to 2 m, provides cleaner data by rejecting false target signals or ignoring air track noise. Use “Standard” setting for distances from 15 cm to 8 m.

Shorter Dead Zone:

  • Detects targets as close as 15 cm from the sensor increasing the effective length of a dynamics track (other motion sensors have a dead zone of 42 cm).

False Target Rejection Circuit:

  • Reduces false signals from objects near the target’s path of motion, giving cleaner data.


  • Switch selectable short range and long range settings
  • Shorter Dead Zone: Detects targets as close as 15 cm
  • False Target Rejection Circuit: Reduces false signals from nearby objects
  • Snaps onto PASCO dynamics tracks or mounts directly to rods for easy positioning


  • Experiments in which both speed and direction are required
  • Study conservation of energy and momentum during collisions
  • Monitor the sinusoidal motion of a mass on a spring
  • Monitor the motion of large objects, such as a student

How It Works

When triggered, the electrostatic transducer in the motion sensor transmits a burst of 16 ultrasonic pulses with a frequency of about 49 kHz. The ultrasonic pulses reflect off an object and return to the sensor. The target indicator on the sensor flashes when the transducer detects an echo.

The interface measures the time between trigger rising edge and the echo rising edge. DataStudio uses this time and the speed of sound to calculate the distance to the object. To determine velocity, DataStudio uses consecutive position measurements to calculate the rate of change of position. Similarly with acceleration.

Software Required

This product requires PASCO software for data collection and analysis. We recommend the following option(s). For more information on which is right for your classroom, see our Software Comparison: SPARKvue vs. Capstone.

Interface Required

This product requires a PASCO Interface to connect to your computer or device. We recommend the following option(s). For a breakdown of features, capabilities, and additional options, see our Interface Comparison Guide.

Recommended Accessories

Motion Sensor Guard SE-7256
Motion Sensor Bracket PS-2546
Cart Adapter Accessory ME-6743
Accessory Cable – Motion Sensor CI-6748
Elastic Bumper ME-8998

Supporting Documents

Motion Sensor II Manual

Principle of Operation – Motion Sensor

Manual Downloads

Product Manuals for the Motion Sensor II (CI-6742A)

Motion Sensor II Manual (CI-6742A)
(527 KB – .pdf – English)

Motion Sensor II Manual (CI-6742)

(236606 – .pdf – English)


Accessory Cable – Motion Sensor

Allows the use of the Motion Sensor (CI-6724A) with additional interfaces.

Motion Sensor Bracket

Easily mount a Motion Sensor to the ceiling or vertical metal surface, such as a metal-backed whiteboard.

Motion Sensor Guard

A metal wire guard that protects the Motion Sensor (PS-2103A) when dropping objects from above the sensor.