Zero friction, low power consumption, and low latency are the key feature of the technology. The torque sensing is based on strain gauges and is easy to use with any type of metal.
The sensor interface is customized to fit any motor controller.
Designing e-bikes for less than 100 ms pedal-input-to-motor-output delay is key to safety (predictability), ride feeling (fun), and improved battery range. The SG2Q technology was created to help you do just that.
Features
- Fast torque and cadence output
- Optional temperature and inclination
- Contactless, zero friction operation
- Low power consumption
- Fully customized to fit the application
- For e-bikes, EV/LEV, and industrial
Specifications
Torque
- Range: Custom. Typical ±300 Nm
- Accuracy: Typical ±1-2 %
- Linearity: Typical ±1-2 %
- Latency: 5 ms ±1 ms [analog], 1-2 ms [digital]
- Frequency response: Typical 500 Hz
- Sample rate: 1000 Sa/s
- Analog output: Custom. Typical 10 mV/Nm, 0-5 V
Electrical
- Interface: Custom. Analog/Serial/I2C/SPI/CAN/Modbus/IO-link etc.
- Power supply: Custom. Typical 3.3-5.5Vdc or 4-13.5Vdc
- Power consumption: Max 50mA
Cadence
- Range: ±220 RPM
- Pulses per rotation: Custom. Typical 128 (equivalent)
- Latency to stop: Custom. Max 40 ms (5-220 RPM)
- Angle to start: Custom. Max 1.5 deg
- Frequency response: 10 kHz (equivalent)
Environmental
- Operating temperature: -20°C to +85°C
- Protection: Allows potting, sealing, or coating to obtain IP67+
Documentation
Description
The SG2Q module set is designed as a very responsive contactless torque sensor module. It is suitable for a range of applications involving torque measurements on a rotating shaft/spindle using a strain gauge sensor. A prime example application is an e-bike mid-drive motor for higher-end e-bikes where responsiveness and accuracy are key to providing the best rider experience.
By using wireless power and data transfer, the rotating torque shaft side is free of any batteries. A one-millimeter air gap between the rotor part and the stator part provides a friction-free solution. The sensor is ideal for reliable measurement of static and dynamic torque on both non-rotating and rotating components. Integration into an e-bike system is easy by using the optional CAN bus interface or the direct analog torque output.
Zero friction and low power consumption for the fairly high accuracy achieved is the key feature of the technology, along with its compact design and customizable form factor.
High reliability through the use of automotive-qualified components (AEC-Q).
Form factor
For a radially constrained design, a typical OD is from ID + 15mm. For an axially constrained design, a typical OD is from ID + 30mm. In the axial direction, the typical minimum size is 4mm plus mechanical fixation (also depending on strain gauge type).
See also the Customer form factor examples catalog
Applications
See examples of the contactless torque sensor module in various customer application designs in the references section. We see applications ranging from high-end E-MTB over urban e-bikes to 2-seater light electric vehicles and industrial applications.
For an overview of the different technologies used to make e-bike torque sensors, please see the technology comparison.
