Commutator PRO

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Overview

The Commutator Pro is a high-performance, motorized commutator designed to prevent tether tangling during neuroscience experiments, ensuring smooth and uninterrupted behavioral recordings. It can operate using external power or its integrated, rechargeable lithium battery, offering flexible deployment options. A built-in microprocessor, working in tandem with a rotary magnetic sensor and/ or an external gyroscopic sensor, actively manages cable orientation by automatically counteracting twists.

The system is highly configurable, supporting up to four Neuropixels ports alongside a conventional probe driven by either recording or stim-record headstages, and offers up to nine GPIO channels for user-defined applications. Its adaptable mounting and cable management system, complemented by an optional passthrough channel, enables seamless integration across a wide range of experimental setups—providing robust performance and maximum versatility.

Key Features

Dual Sensor Options

• Gyroscopic Sensor

Ideal for seamless behavioral integration, especially in small animal setups. Can be easily adapted.

• Magnetic Sensor

Integrated magnetic encoder detects rotation without external sensors. Recommended for rats and non-Neuropixels experiments.

Neuropixels & Passive Probe Support

• Supports up to 4 Neuropixels probes.


• Supports simultaneous Neuropixels and passive probe (e.g. electrical stimulation) operation.

Integrated Sensor Cable

• Lightweight (< 1g) and highly flexible 34 AWG wire bundle.


• Compatible with all existing headstage setup.

Optional Fluidic/Fiber Passthrough Channel

• 5 mm inner diameter channel enables optical or fluid access during ongoing experiments.

Low Operation Acoustic Noise

33-35dB. Measured at 30cm away using iPhone 16 Pro (Note: ambient is measured to be 32dB).

GPIO & PC Control

Up to 9 GPIO lines for custom application.

Left/right override via PC or hardware panel.

Model Number

COMP- IH - XH1 - NP1 - PT - B

      Not all combination is possible

Components

Required Customer Provided Parts

1. Compatible power source

USB Power Brick supplying 5V, 1A or AC Power Supply: 20V 1A ; 2.5mm jack (5525)

2. USB-C charging cable, if applicable

Dimension and Weight

 Front view                    Back view

Weight ~825g

unit: mm

Device Overview

LED Indicators

The KonteX Commutator Pro features several LED indicators designed to provide real-time visual feedback on device power status, connectivity, control mode, and battery level. Understanding these indicators is essential for proper setup and reliable operation in laboratory environments.

② Power Indicator LED (White Ring Light)

Function: Indicates that adequate power is supplied to the commutator (the motor drive system) when the main ON-OFF toggle button is toggled to ON.

Behavior:

Solid White: The device is powered and functioning normally.

OFF: The commutator is powered off or not receiving sufficient input voltage.

③ PC Connection Status LED

Function: Indicates the status of USB-C communication with a host computer.

Behavior:

Solid Light ON: The commutator is connected to a PC and has entered Remote Control Mode. In this mode, Sensitivity and Speed are governed by software settings displayed on the PC interface. Manual knob control on the front panel is overridden.

OFF: No active USB connection or operating in local manual mode (hardware knob control applies).

NOTE: The battery is a consumable component and is not covered under warranty. When it reaches the end of its lifespan—evidenced by rapid charging and immediate shutdown upon disconnecting external power—the device remains fully functional when powered externally. To replace the battery, please return the unit for servicing.

Installing the Commutator Pro

Option 1: Undermount

The Commutator Pro can be securely mounted to a behavior box with 3 set screws that are preattached to the commutator. (See Undermount Cutout Installation Sepcification)

Option 2: Camera mount

The Commutator Pro includes a standard 1/4-inch mounting screw socket that is compatible with standard camera mounting accessories. Cost effective camera mounts with articulated arm can be used to easily suspend the Commutator Pro above the recording rig.

Commutator Pro installation diagram

⚠ IMPORTANT: Always ensure the Commutator is mounted level. Installing the Commutator Pro at an angle may lead to increased acoustic noise and accelerated mechanical wear.

Getting Started

Step 1: Powering the commutator

The Commutator Pro can be powered via either the USB-C port or the DC jack. When using the USB-C port—particularly during remote operation under PC control—ensure a stable 5V, 1A power supply, compliant with USB 3.0 or USB Power Delivery (USB-PD) specifications. Powering the device with only 5V, 0.5A (typical of USB 2.0) may result in unreliable performance, including failure to power on or disruptions in motion tracking.

Battery Charging

If your Commutator Pro is equipped with an internal battery (models designated with -B), the battery will begin charging automatically when power is connected. During charging, the front-panel battery level indicator LEDs will flash and illuminate progressively to reflect the current charge level, indicating active charging (see LED Indicators section for details).

Once fully charged, all four power LEDs will remain steadily illuminated. The Commutator Pro is equipped with an integrated Battery Management System (BMS) that prevents overcharging, making it safe to leave the device plugged in during operation.

A full charge takes approximately 7 hours, and under normal operating conditions, the device can run for up to 6-9 hours on a full charge.

Step 2: Connecting to the XDAQ

Use the supplied DAQ cable to connect between a XDAQ headstage port and the appropriate headstage port (Neuropixels or HDMI) of the Commutator Pro.

Step 3: Connecting the Headstage Cable to the Rotating Interface

To connect the headstage cable to the Commutator Pro, locate the headstage port(s) positioned on the underside of the device, which serves as the rotating interface of the commutator.

Identify the appropriate port based on the headstage type (HDMI or Neuropixels) as labeled near each connector. Carefully align the headstage cable connector with the corresponding port and insert it straight and firmly until it is securely seated. These ports are designed to maintain a stable connection while allowing continuous rotation during operation.

⚠ IMPORTANT: - Ensure the cable is connected to the correct port.
- Avoid twisting or pulling the cable during installation.
- It is recommended to power off the device before making connections to prevent hardware damage.
Once connected, signal input from the headstage will be routed through the commutator and transmitted to the corresponding output port on the top of the commutator base.

Step 4: Managing excess cable

When connecting the headstage cable to the Commutator Pro, the signal pathway begins at the rotating interface and exits through the fixed-side rotor side ports. After selecting the appropriate rotor side port (e.g., HDMI or Neuropixels), the user may route the cable toward the downstream recording amplifier.
To ensure stable cable handling during rotation and prevent signal artifacts caused by tension or displacement, proper cable management is essential.
Route the cable as illustrated below and securely lock the cable using the integrated screw clips, ensuring that adequate slack is maintained to prevent tension on the headstage connection and to allow smooth rotation of the commutator.

⚠ IMPORTANT: It is important to leave a small amount of slack in the cable to prevent tension that could affect the device's movement and sensitivity.

Step 5: Sensor configuration

The Commutator Pro can be driven using a compatible animal side gyro sensor or the integrated magnetic encoder. Note: the IMU sensor found in the X-Headstage or Intan stock recording headstages is not compatible with the Commutator Pro.

Gyro Sensor Models (designated with -I or -IH)

I Model:

Connect the integrated gyro sensor cable to the GYRO port on the rotating interface.

IH Model:

Disconnect the integrated gyro sensor cable from the GYRO port, if applicable. Connect a custom headstage that includes a compatible and integrated gyro sensor to the HDMI cable.

NOTE: If no compatible headstage is available, connect the integrated gyro sensor cable instead. The device will not function correctly if both custom gyro headstage and integrated gyro sensor cable are connected.

Magnetic Sensor Model (designated with -M)

This configuration uses the integrated magnetic encoder located on the rotating interface to detect cable rotation. It eliminates the need for the external gyro sensor. No setup is necessary, proceed to the next step.

Combined Gyro & Magnetic Sensor Model (designated with -MI)

To use Gyro sensor as the primary input:

If your Commutator Pro supports both gyro and magnetic Sensor:

IH Model:

Plug the integrated gyro sensor cable into the GYRO port on the rotating interface. When a valid gyro signal is detected, the magnetic encoder input will be automatically ignored.

To switch to Magnetic encoder sensor:

Disconnect the gyro sensor cable. Release the lock screw securing the cable encoder attached to the magnetic encoder.

     Bottom view               Front view

NOTE: When using the gyro sensor, ensure the lock screw is fastened to secure the cable encoder in place.

⚠ IMPORTANT: The gyro sensor must be connected to the Commutator PRO before powering on to ensure proper operation.

Step 6: Connecting GPIO

This interface allows users to transmit analog or digital signals from external equipments. The signal enters via the fixed-side GPIO DB9 port and is routed directly to the rotating-side port, enabling seamless integration with devices mounted on the animal.
A pre-assembled cable for accessing the rotating-side GPIO is available for purchase from Digi-Key or Mouser. To locate compatible options, search for 'JST SH' connector (10-pin).

NOTE: GPIO signal can be routed through the HDMI port at the expense of reduction of maximum supported number of headstage channels. Contact us for the customization. Such customization should be done at the time of the order.

       Bottom view

Step 7: Connecting to the headstage, setting up Gyro sensor and turning on

Connect the headstage cable to the headstage

Attach Gyro Sensor to the Headstage or Cable

Attach the gyro sensor to the headstage or the headstage cable using adhesive or other suitable methods.

Ensure the sensor is perpendicular to the moving plane and parallel to the cable; do not rotate its orientation.

Power On

Press and hold the power button for one second. The LED indicator will flash three times to confirm the device has successfully powered on.

Press and hold the power button again for one second to power off the device.

⚠ IMPORTANT: The gyro sensor must be connected to the Commutator PRO before powering on to ensure proper operation.

Magnetic Sensor Sensitivity & Speed Controls

When using the KonteX Commutator Pro with Magnetic Sensor, two physical adjustment knobs labeled Sensitivity and Speed are available on the control panel. These knobs allow users to manually tune the system’s behavior based on the movement profile of the experimental subject.

   Front view

① Sensitivity Knob

Function: Adjusts the magnetic sensor sensitivity (7 increments) of the Hall effect sensor.
Effect: Higher sensitivity increases the system’s responsiveness to small rotational movements of the tether, triggering sensor compensation with less motion input. Usage Scenario:

• Small animals (e.g., mice) or low-activity experiments: Turn the Sensitivity knob clockwise to increase responsiveness.
• Large animals or highly active behavior: Reduce sensitivity to avoid overcompensation and motor jitter.

② Speed Knob

Function: Controls the rotation amplitude and velocity (7 increments) of the compensating motor in response to detected movement.
Effect: Higher speed settings result in faster and larger motor responses, while lower settings make the compensation gentler and more gradual. Usage Scenario:

• For rapid or vigorous animal movements, increase speed to prevent cable tension buildup.
• For delicate behaviors (e.g., head-fixed setups or fine-motor experiments), reduce speed for smoother operation.

Using the Commutator PRO with Intan or Open Ephys Acquisition Systems

Perspective

uHDMI to RHD Adapter
SKU: SAdpt-uHDMI-OM12

uHDMI to RHS Adapter
SKU: SAdpt-uHDMI-OM16

Bottom view

XDAQ to RHD Headstage Adapter
SKU: SAdpt-XDAQ-OM12

XDAQ to RHS Headstage Adapter
SKU: SAdpt-XDAQ-OM16

Left & Right Manual Control

The Commutator Pro control panel is equipped with left and right rotation buttons, allowing manual adjustment of the commutator’s rotating end. These controls allow for accurate repositioning with each button press.

-M or -MI Model

-I or -IH Model

Tested Cable Configuration

For custom cable length configurations, please contact us to discuss customization and validation options.

PC Interface

The USB-C port on the KonteX Commutator Pro serves as a multi-functional interface for both device configuration/control and power supply.

Configuration and Control

When connected to a PC via USB-C, the Commutator Pro allows real-time:

Device configuration (e.g., sensor mode selection, motor response tuning)

Firmware updates

Live monitoring and override control (e.g., manual rotation triggers, gyro/Hall sensor calibration)

The USB-C interface communicates through a dedicated software utility or custom API, enabling integration into automated behavioral or electrophysiological setups.

     Charging Ports

Undermount Cutout Installation Sepcification

Cutout Dimensions Diagram  

unit: mm

Pin Map

# of GPIO available always start from left and count to right.

Example, if the Commutator has 3 GPIO, then pin 5, 9 and 4 are available.

Model with Passthrough Channel (-PT)

         Passthrough Channel Dimensions Diagram

unit: mm

Mitigating EMI-Induced Errors in GMSL Differential Signal Routing Near Power-Switched Commutators

The Commutator Pro is designed to provide reliable power switching in high-speed data transmission systems such as NP Serial Transmit applications. When operating with GMSL differential signals, users must take precautions to avoid electromagnetic interference (EMI) that may lead to errors during PRBS or serial transmission testing.

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