Motion Tracking Antennas Components
The choice of a specific antenna depends on its physical size, magnetic field, and resolution, as well as the system size and functionality. Low-frequency antennas, also known as LF antennas, range from 10 to 120 kHz, generate long-wavelength radar energy that can penetrate up to 50m or more under certain conditions, but can provide only very large subsurface features. Instead, the magnetic field of a 900MHz antenna is about 1m, and often less, under typical ground conditions, but its reflections can achieve down to a few centimeters in diameter [1].
Due to their increasing range of applications and the big impact that implies the integration of LF antennas in mobile devices, we would like to review the availability of Motion Tracking Antennas (or LF antennas) provided by PREMO. All these components are Emitter 3D cubic magnetic antennas for magnetic tracking sensor systems. They are designed for VR/AR applications (gaming, simulation, etc.) and motion capture applications. Their main feature is a low latency compared with other motion tracking technologies.
Let’s review the different types of antennas available.
⦁ 3DCC20 COMPONENT
This a 3D Coil Cube Magnetic emitter for Virtual Reality magnetic tracking systems. Its medium size, with an internal core of about 20×20 mm, means that they are suitable to be integrated in small devices. As the diagram shows, its size is 30.7×30.75×30.7mm.
It implements THT technology and offers a medium range and high sensitivity solution. Its inductance range is 300-600μH (low inductance) and 1-1.5mH (high inductance). This component has a sensitivity of around 18 mVpp/App/m @20kHz (low inductance) or 32 mVpp/App/m @20kHz (high inductance). It features also a high axis symmetry (X, Y, Z) repeatability (very good isotropy) and accuracy (tolerance of up to 2%). Its mounting method is PHT and its temperature range is from -20°C to 85°C.
There are two versions of this component, and their specifications are shown on the following table.
Its electrical diagram depends on the selected component; however, both share the same pinouts and structure.
It is possible to find more information about these components at the PREMO Group webpage for the 3DCC20 Component.
⦁ 3D20LW COMPONENT
This component is a 3D Coil Cube Emitter for VR magnetic tracking system that presents a light weight (30g). It is a medium size isotropic sensor that integrates a lightweight core and measures 20x20x20mm. It implements THT technology, just like the previous component. As we can see in the diagram, its size is 30.7 x 30.75 x 30.7 mm.
Its electrical diagram has 8 pins – pins 7 and 8 are not connected.
You can find more information about this component at the PREMO Group webpage for the 3D20LW Component.
⦁ 3DCC28 COMPONENT
This component is a bit bigger than the previous one. It is a big isotropic 3D cubic magnetic tracking sensor, with an internal core of 28 x 28 x28 mm. It uses THT technology as the previous models, a provides a long range and a high sensitivity. Its inductance ranges from 350-600μH (low inductance) and 1-3mH (high inductance). The following diagram illustrates the size of the component which is 39.5×39.5×38.6mm.
This component features a high axis symmetry (X, Y, Z), repeatability, very good isotropy and accuracy with up to 2% tolerance. Its magnetic sensitivity is about 60 mVpp/App/m @20kHz for high inductance and 30 mVpp/App/m @20kHz for low inductance. It is available in different frequencies, 20 kHz, 125 kHz and 134 kHz, all of them with a temperature range of -20°C to 85°C.
There are two versions of this component and their specifications can be seen on the following table:
The following picture shows the component’s electrical diagram and its configuration for each version.
For more information about this component you can check the PREMO Group webpage for the 3DCC28 Component.
⦁ 3D28LW COMPONENT
As the previous model, this component is also a big isotropic 3D cubic magnetic tracking sensor, with an internal light weight core of 28x28x28 mm. The main difference between both models is the light weight of the 3D28LW (about 65g). The 3D28LW measures 39.5×39.5×38.6mm.
It uses THT technology, with an inductance range of 1.5-3mH (high inductance) and a sensitivity of 54 mV/A/m. There is only one version of this component and its specifications can be seen on the table below:
The following picture shows the component’s electrical diagram and its configuration for each version.
More information about this component can be found at the PREMO Group webpage for the 3D28LW Component.
⦁ 3DCD90 COMPONENT
This component differs from the previous ones firstly in its shape and features. It is made of 3 orthogonal coils and the component is oriented in 3 axes with full functionality. This device offers a 3D emitter antenna for VR/AR applications. A picture and a diagram of the component are shown below:
This component provides a high electrical stability and its operating temperature ranges from -20°C to 65°C. This a solution for extra long-range requirements, available in different inductance values and with two versions of the component. Its specifications are shown on the following table:
If you need extra information about this component, you can check the PREMO webpage of the 3DCD90 Component.
⦁ 3DTX08 COMPONENT
This three-axis magnetic antenna is another antenna suitable for magnetic tracking systems. It has a high axis symmetry (X,Y,Z) and repeatability thanks to its very good isotropy and good accuracy, with a tolerance of up to 5%. The following diagram shows its size of 16.5×14.8×11.8 mm.
This component offers an excellent magnetic sensitivity of 2.6 mVpp /App/m @20kHz and a temperature range from -20°C to 85°C. It uses the SMT (Taped & Reeled) mounting method and it is available in multiples frequencies (20kHz, 125kHz, 134kHz). There is only one version of this component and its features are as follows:
The following diagram illustrates the component configuration:
For more information about this component, please check the PREMO Webpage of the 3DTX08 Component.
⦁ 3DTX10 COMPONENT
This component is similar to the previous one, with several variations in terms of magnetic sensitivity and size, among others. It has high axis symmetry (X,Y,Z), repeatability and excellent accuracy, with a tolerance of up to 5%. Its size is 17.4×15.2×13.9mm, a bit bigger than the previous model. The following pictures illustrate the component, its structure and size.
Among its specifications, it offers a very good magnetic sensitivity with values of 3.8 mVpp/App/m @20kHz, a temperature range of -20°C to 85°C and SMT mounting. It is available in multiple frequencies such as 20kHz, 125kHz and 134kHz. There is only one version of this component, and its specifications are as follows:
Its electrical diagram is included in the following image.
Please visit the PREMO Webpage for more information about the 3DTX10 Component.
⦁ COMPARISON
After describing all the magnetic tracking antennas available from PREMO Group, the following table offers a comparison of their specifications.
The chosen component will depend of the device where it is to be implemented, as well as the application.
References
[1] A. Benedetto, F. Benedetto. Application Field–Specific Synthesizing of Sensing Technology: Civil Engineering Application of Ground-Penetrating Radar Sensing Technology. Comprehensive Materials Processing. Volume 13, 2014, Pages 393-425.
[2] Premo Group Webpage https://www.grupopremo.com/612-tx-em-motion-tracking-antennas.
