Electromagnetic 3D Motion Trackers

Electromagnetic Technology based 3D Motion Trackers have many features that make them suitable for Biomechanics, Virtual Reality, Biomedical 3D Imaging, Sports Analysis, Behavior Studies, Simulation and Avionics. Their features are listed below.

  1. Low Cost.
  2. No lighting conditions, background or line of sight constraints.
  3. No drift.
  4. 6 DOF data per sensor.
  5. Both wireless and wired models.
  6. Real-Time operation. Lowest latencies available in the market.
  7. Portable.

Following Electromagnetic 3D Motion Trackers available:

Polhemus 3D Motion Trackers:

Polhemus is the pioneer and world leader of Electromagnetic Technology based 3D Motion Trackers. They make many models of motion trackers .

Patriot, Patriot DB and Partriot Wireless:

Patriot and Patriot wireless are 2 sensor capablle, 6DOF Motion Trackers. it has 60 Hz sampling rate per sensor. Patriot is also available in PatriotDB Version, that has small Electronic Unit that goes in Optical Drive bay of computer. This has appliction in location based entertainment, Ergonomics, Stereotaxic Localization and Tool/Head Tracking for 3D Biomedical Simulation.Patriot Brochure.pdf, Patriot DB Brochue.pdf , Patriot Wireless.pdf


Fastrak is industry's old warhorse, 4 sensor capable, 6DOF Motion Tracker. it has 120 Hz aggreagte sampling rate . For 1 sensor, it offers 120 Hz, for 2 , 60 Hz, for 3 40 Hz, and for 4 sensors , effective sampling rate would be 30 Hz per sensor. Fastrak has been used for head and instrument tracking, 3D Biomedical imaging, Body tracking for Biomechanical analysis, Telerobotics and Computer Graphics since 1994.

Fastrak Brochure.pdf

Liberty and wireless Latus:

Liberty is state of the art, 16 sensor cpable, 6DOF Motion Tracker while Latus is 12 wireless markers capable, upto 16 receptor chennels to increase tracking range. Liberty offers 240 Hz sampling rate per sensor whereas Latus offers 188 Hz sampling rates per wireless marker for upto 8 markers and 94 Hz for upto 12 markers. Theese models are most versatile as fas as application is concerned, be it Sports Biomechanics, Gait Analysis, Virtual Reality, Behavior studies, Telerobotics , Simulation and much more.


There are various accessories available for Motion Trackers above.


RX2: This is standard sensor for Patriot, Fastrak and Liberty Trackers.

RX-1D: This is small, tear drop shaped sensor for specific requirements.

RX-1C: This is small, flat sided sensor for small environment for Patriot, Liberty and Fastrak.


TX2: This is standard source with range of +/- 2.5 feet spherical tracking range around it.

TX1: This is small range source<img> with tracking range of +/- 1 feet. This is usefull for small range application where small sized source and minimum metal distortions of this source due to small electromagnetic field is required.

TX4: This 4" source has larger spehrical tracking range of +/- 4 feet. Long Range Source: This is longest range source with tracking range of +/- 7.5 feet.


8" Stylus: This is 8" Stylus to convert Patriot, Fatrak and Liberty Trackers into free form digitizer.

3" Stylus: This is smaller stylus that can reach hard to reach crevices.

Wanda: This is a 3D Interaction device that can house a 6DOF sensor, for Vitual Environments and has 3 Programmable buttons.. Accessories Brochure.pdf


The Micro Sensor 1.8 is one of the latest breakthroughs from Polhemus, the leaders in motion measurement innovation. This 6DOF (6 Degree-Of-Freedom) micro sensor tracking element utilizes Polhemus proprietary AC electromagnetic technology, weighs in at less than a gram, and measures only 1.8 millimeters in OD (outer diameter). Small and lightweight, it packs an enormous amount of capability into its small size and provides both position and orientation data, at speeds up to 240 Hz (frames of data per second), depending on tracker model.

Like all Polhemus tracking technology, the new Micro Sensor 1.8 requires no line-of-sight to continuously track its position and orientation. Better still, Polhemus sensors are completely embeddable into a variety of custom form factors, ideal for fitting inside a traditional catheter, a head-worn device, such as an HMD, simulated medical tools, or even slipped under gloves or clothing. This makes the Micro Sensor 1.8 an ideal tracking solution for applications requiring not only high-fidelity precision tracking, but also small-scale sensor size.

Polhemus technology has been used in the healthcare market for years, including healthcare simulation and real-world applications such as enabling image guided surgery. The Micro Sensor 1.8 adds new capability and value to healthcare and other important markets.

Currently for use with Polhemus G4, LIBERTY™ and PATRIOT™ motion tracking systems, the Micro Sensor 1.8 offers tracking capabilities of up to 16 sensors simultaneously per system. Polhemus AC electromagnetic technology allows for multiple tuned magnetic tracking sources which enables you to run independent tracking systems right beside each other without concern for magnetic overlap (cross talk). Learn more about the Polhemus LIBERTY and PATRIOT tracking systems and get detailed information on accuracy, update rates and tracking system specifications.

Above: Micro Sensor 1.8 inserted in catheter tubing and embedded in 3D heart model, finger and hand tracking with multiple sensors


Full 6DOF motion tracking (measures both position and orientation)

1.8 millimeter OD (Outer Diameter)

Embeddable, no line-of-sight required

Highly precise and accurate

Lightweight, sensor head weighs less than a gram

Update rates as high as 240 Hz Track up to 16 sensors simultaneously, per system


Healthcare simulation

6DOF hand and finger tracking

Head tracking (watch the video)

Catheter applications

Image guided surgical simulations/procedures Limb tracking (biomechanics)

Research studies




G4 is a wireless motion tracking system that delivers full 6DOF (6 Degree-Of-Freedom) tracking, providing both position and orientation without hybrid technologies. Allowing the user complete freedom of movement, the entire system can be set up in minutes. As with all Polhemus tracking systems, G4 utilizes our proprietary AC electromagnetic technology. This means G4 tracks through most walls, as no line-of-sight is required for continuous tracking. Key features are highlighted below, see the G4 brochure for a complete description and product specifications.

Watch the G4 product video to get a full overview of its capabilities.

Add the PowerTRAK 360™ for a 3D handheld remote that delivers an unmatched level of superior tracking and precision accuracy.


Wireless Tracking

Tetherless tracking utilizes a wireless data transmitting system. Position and Orientation is sent wirelessly to the PC via RF links. Our proprietary technology tracks through walls—and people.

10+ Hours of Battery Life

Track in the field or in the lab all day, without having to start and stop because of battery life. The long-life battery is easily recharged via the wall charger.


The G4 system is compact and portable, and the system electronics unit (hub) can be belt worn. This allows you to change or move your tracking environment quickly.

Auto Tracking

Recognition The G4 system has auto tracking capability, meaning G4 will re-acquire the signal as a tracked subject walks back into the field of tracking range.


The standard G4 system includes one hub, one source and one sensor. One of the most impressive features of G4 is the product can be scaled up to continue to meet your needs as they evolve. As your applications change or expand, you can add components to increase G4's capabilities. If you need to increase the number of people or objects being tracked, you can add up to nine hubs; increase the field of range by adding up to eight sources.


Rehabilitation and Physical Therapy


Sports Motion Analysis

Training and Simulation .

Cave and Dome Environments

Power Wall Applications

Ergonomics Studies

Human Factors Engineering

Add the PowerTRAK 360™ for a 3D handheld remote that delivers an unmatched level of superior tracking and precision accuracy.


Do you need a motion tracker with high-speed update rates, virtually no lag time, yet small, scalable and customizable?

VIPER™ is the latest iteration of electromagnetic motion trackers by Polhemus. With speeds up to 960 Hz, latency as low as 1ms & smart sensing technology, Viper offers scaled-up capability in a scaled-down package.

Users can customize the VIPER motion tracking system by choosing one of three SEU (System Electronic Unit) sizes. You decide the number of tracking sensors for your application—up to 16 per system.

Select one source or add multi-source capability to customize tracking coverage for your unique needs. Polhemus EM (Electromagnetic) tracking gives you position and orientation tracking for sensors for people or objects – you can even embed the sensor inside your device!

Environment-friendly, Polhemus technology can track people and objects through clothes, hats, gloves, and even walls--daylight, low light, and even no light--Polhemus EM makes the difference! And our latest tracker, VIPER, takes EM tracking to the next level with its performance, accuracy, and feature capability.



240Hz per sensor max (VIPER 4)

960Hz per sensor max (VIPER 8/16)


USB; RS-422, both standard; dual output available.


1ms at 960Hz/ 2ms at 480Hz/ 3ms at 240Hz


0.015 in. (0.38mm) RMS for X, Y, Z position;

0.10° RMS for sensor (FT-Standard) orientation*

(Non-standard, smaller sensors may reduce the specified range slightly)


0.00004 in. (0.0010 mm) at 12 in. (30 cm) range;

0.0003° orientation


Useful operation up to 72 in (182 cm) and beyond** Specified accuracy within 30 in (76 cm) radius from Source, at above static accuracy specifications


Sync signal can be used as input or output to sync to or from another device


10° to 40°C


5 Volts DC @ 5.5 Amps direct or 24 Volts DC @ 1.3A via external DC-DC converter 32 Watts


User adjustable position & orientation prediction built-in


GUI and SDK included

Microsoft Windows® 10 Ready

Unity: Sample open source code included

Linux: Sample open source code included


EMC/EMI: IEC 60601-1-2

Medical Electrical Equipment, Edition 4.0

Electrical Safety Approvals: IEC 60601-1

Medical Electrical Equipment, Edition 3.1


  • Ultra-Fast Update Rate. Up to 960 Hz
  • Ultimate Accuracy
  • Latency as Low as 1 Millisecond
  • Up to 16 Sensors Per System
  • Scalable—Add Sources to Increase Coverage Area
  • Small, Lightweight, Portable SEU
  • FTT®—(Fly True Technology) Means Smart Sensing Distortion Mitigation Technology

Once toggled on, this feature compensates for distortion, if needed, on-the-fly, to ensure high-fidelity tracking in even the most challenging environments.

The VIPER™ system allows you to select from three different Systems Electronics Units. Then choose one or more sensors (up to 16), and one or more sources (up to 4 per SEU) to complete your system. There are multiple sensor options, with varying size, shape, and capabilities. Select one type, or mix and match sensors, based on your needs. Choose from three different sources.


  • Medical Simulation
  • Clinical Applications
  • Biomechanics & Sports Analysis
  • Head Tracking
  • Automotive Applications
  • Robotics Tracking
  • Manufacturing Environments