Go Direct^® Rotary Motion Sensor

GDX-RMS—Sensor only
GDX-RMPK—Sensor + Accessory Kit

Specifications and User Guide

Troubleshooting

General: Press the power button on the sensor to turn it on. Connect your sensor as described in the Getting Started instructions for your device.

• Primary Test: Rotate the axle to verify that the sensor readout changes as expected (i.e., one full revolution is approximately ±6.28 radians).

Additional Troubleshooting

• Will my Go Direct Rotary Motion sensor fit into the Polarizer/Analyzer equipment?
• What is the highest rate of rotation for the Rotary Motion Sensor (standard and Go Direct)?
• What are the dimensions of the 3-step pulley/wheel on the Rotary Motion Sensor?
• With which rotary motion sensors does the Vernier Rotational Motion Accessory Kit (AK-RMV) work?
• What are the moments of inertia of the disks included in the Rotary Motion Accessory Kit?
• How do I measure linear position with a GDX-RMS in Graphical Analysis or Graphical Analysis Pro?
• I can't get my accessories to attach to the Go Direct Rotary Motion Sensor.
• What are some experiment ideas I can do with a Rotary Motion sensor?
• Go Direct sensor does not connect to LabQuest 2 via Bluetooth.
• How do I remove or replace a Go Direct battery?
• Troubleshooting Bluetooth Connections with Go Direct Sensors
• What can I do if a Go Direct sensor's Bluetooth LED flashes red and green when I try to connect to it and the connection fails?
• Will my device work with Go Direct Sensors via Bluetooth?
• How do I know if my LabQuest will work with Go Direct Sensors and Go Wireless devices?

Specifications

• Optical encoder: Bidirectional, quadrature encoder, 360 cycle per revolution
• Resolution: 1° or 0.25°
• Maximum Speed
  ⚬ 1° resolution: 30 rev/s
  ⚬ 0.25° resolution: 7.5 rev/s
• 3-step Pulley Dimensions
  ⚬ Groove diameters: 10 mm, 29 mm, and 48 mm
  ⚬ O ring diameter (when in outer groove): 55 mm
• Connections
  ⚬ Wireless: Bluetooth^® v4.2 (wireless range 30 m unobstructed)
  ⚬ Wired: USB 2.0 full speed
• Battery: 300 mAh Li-Poly
  ⚬ Battery Life (single, full charge): ~24 hours continuous data collection
  ⚬ Battery Life (lifetime): 2 – 5 years (typical)

For specifications on the Rotational Motion Accessory Kit parts, see What are the moments of inertia of the disks included in the Rotary Motion Accessory Kit?

Battery Troubleshooting

1. If the sensor can be turned on when connected by USB but not when disconnected from USB, the battery either needs charging.
   ⚬ Try charging the sensor for several hours and testing again.
2. If after charging the battery the sensor turns on while connected via USB and briefly connects to Graphical Analysis but gives repeated communication errors and/or resets the selected wavelength, then the battery may be bad. To verify this is a battery issue (and not a bad USB port or cable), try swapping the battery with a working sensor to see if the problem follows the battery or stays with the sensor.
   ⚬ If the problem stays with the sensor, the battery is probably not the issue.
   ⚬ If the problem follows the battery, the battery has likely reached its end of life.
3. In this state, the sensor cannot be used even if connected by USB, so the battery will need to be replaced. Go Direct® 300 mAh Replacement Battery (GDX-BAT-300)
4. See How do I remove or replace a Go Direct battery? for more information (including a video).

Rechargeable batteries are covered by a one-year warranty.
Batteries should last two to five years in typical use.