Understanding the Difference Between Cadence and Torque Sensors in eBikes

Introduction:
In the world of electric bicycles (eBikes), two commonly used sensors are cadence sensors and torque sensors. These sensors play a crucial role in determining how the motor assists the rider during pedaling. This article aims to explain the differences between these two sensors and provide examples to illustrate the working principle of torque sensors using real-world data.

Cadence Sensors:
Cadence sensors are the most basic type of sensor found in eBikes. They measure the rotation speed of the cranks or pedals. By detecting how fast the rider is pedaling, cadence sensors provide information to the motor controller, which then adjusts the level of motor assistance accordingly. However, cadence sensors do not measure the force applied to the pedals, resulting in a less precise and responsive assistance system.

Torque Sensors:
On the other hand, torque sensors provide a more advanced and accurate measurement. They detect the actual force exerted by the rider on the pedals, providing a direct indication of the rider's effort. Torque sensors measure the force in the pedal crank or bottom bracket area and send this information to the motor controller. This enables the motor to provide assistance that is proportional to the rider's input, resulting in a more natural riding experience.

Working Principle of Torque Sensors:
To understand the working principle of torque sensors, let's consider an example. Suppose a rider exerts a force of 50 Newtons on the pedals. The torque sensor, located in the bottom bracket, measures this force and sends the information to the motor controller. Based on the rider's input, the motor controller determines the level of assistance required.

For instance, if the rider is climbing a steep hill, the motor controller will apply a higher level of assistance to help overcome the increased resistance. In contrast, when riding on a flat road, the motor assistance can be adjusted to a lower level as the rider requires less assistance.

The real-time data provided by torque sensors allows for precise and dynamic control over the motor assistance, resulting in a seamless integration between the rider's effort and the motor's support.

Conclusion:
While cadence sensors offer a basic level of assistance by measuring pedal rotation speed, torque sensors provide a more sophisticated and responsive riding experience by measuring the actual force applied to the pedals. Torque sensors enable eBikes to provide assistance that aligns with the rider's effort, resulting in a more natural and intuitive ride. With their ability to measure force in real-time, torque sensors enhance the overall performance and efficiency of eBikes, making them a preferred choice for riders seeking a more engaging and personalized riding experience.