To Torque or not to Torque: More about Pedal Assist

What are the difference between the cadence  sensor vs torque sensor?

Pedal Assist is a technology used in electric bikes (e-bikes) that provides assistance to the rider when pedaling. There are different types of sensors used in Pedal Assist systems, including cadence sensors and torque sensors. Here’s a description of each:

1. Cadence Sensor: A cadence sensor measures the rotation speed of the bike’s pedals, typically in revolutions per minute (RPM). It detects when the rider is pedaling and sends a signal to the e-bike’s motor to provide assistance based on a predetermined level or setting. The assistance is typically proportional to the speed at which the rider is pedaling. Cadence sensors are generally simpler and less expensive compared to torque sensors.

Pros of Cadence Sensors:

• Cost-effective: Cadence sensors are typically less expensive to implement in e-bike systems.
• Easy to Use: They are generally easier to set up and require minimal calibration or adjustment.
• Consistent Assistance: The assistance provided by cadence sensors is often more consistent and predictable.

Cons of Cadence Sensors:

• Lack of Precision: They do not measure the force or effort applied by the rider while pedaling, which means the assistance level may not be directly linked to the rider’s exertion.
• Less Responsive: Cadence sensors may have a slight delay in detecting changes in pedaling speed, resulting in a slightly delayed response in assistance.

2. Torque Sensor: A torque sensor measures the force or torque applied by the rider while pedaling. It detects the amount of pressure or effort the rider is exerting on the pedals and adjusts the assistance level accordingly. The more force the rider applies, the more assistance the e-bike provides. Torque sensors provide a more intuitive and responsive riding experience, as the assistance is directly linked to the rider’s pedaling effort.

Pros of Torque Sensors:

• Precise Assistance: Torque sensors provide more precise and proportional assistance based on the rider’s pedaling effort.
• Responsive: They offer a more immediate response to changes in the rider’s pedaling force, providing a smoother and more natural riding experience.
• Customizable: Torque sensors can be programmed to adjust the assistance level based on rider preferences or specific riding conditions.

Cons of Torque Sensors:

• Cost: Implementing torque sensors in e-bike systems can be more expensive compared to cadence sensors.
• Calibration and Maintenance: Torque sensors may require more calibration and maintenance to ensure accurate readings and consistent performance.

Overall, while both cadence sensors and torque sensors provide Pedal Assist in e-bikes, torque sensors offer a more sophisticated and responsive experience by adjusting assistance based on the rider’s actual pedaling effort. However, the choice between the two technologies depends on the desired riding experience, cost considerations, and specific requirements of the e-bike manufacturer.