Zemic Europe B.V. (Netherlands) - The Role of Force Sensors in Electric Bicycles: Enhancing Performance and Riding Experience.

By Alex van Wijk Regional Sales Manager, Zemic Europe B.V.

Electric bicycles, commonly known as e-bikes, have gained immense popularity in recent years due to their ability to blend human pedaling power with electric assistance, resulting in an efficient and eco-friendly mode of transportation. With advancements in technology, e-bikes have seen significant improvements in terms of power delivery, range, and overall performance. One crucial aspect that contributes to these enhancements is the integration of force sensors and strain gauges in e-bike designs. In this article, we will explore the role of force sensors in e-bikes and how they enhance the riding experience.

Understanding Force Sensors:

Force sensors, also known as load cells, are devices that measure the force or load applied to them. These sensors convert the physical force into electrical signals, which can then be processed and used for various applications. In the context of e-bikes, force sensors are integrated to measure the force exerted by the rider on the pedals or handlebars, enabling the system to provide appropriate assistance levels based on the rider's input.

Enhanced Pedal Assistance:

Force sensors play a critical role in determining the level of electric assistance provided by the e-bike's motor. By measuring the force applied to the pedals, the sensor provides real-time feedback to the motor controller, allowing it to adjust the assistance level accordingly. For instance, when the rider applies more force to the pedals, indicating a need for more assistance, the force sensor relays this information to the motor controller, resulting in an increased power output from the motor. Conversely, when the rider eases off the pedaling, the force sensor detects the reduced force and adjusts the assistance level accordingly.

This dynamic assistance system provides a more intuitive and responsive riding experience. Riders can enjoy a seamless transition between human-powered pedaling and electric assistance, as the force sensors ensure a harmonious synchronization between their efforts and the e-bike's motor power. This capability not only improves performance but also contributes to better energy efficiency, as the motor adapts its output to the rider's needs in real-time.

Optimized Torque Sensing:

In addition to pedal force measurement, force sensors can also be utilized for torque sensing in e-bikes and sport bikes. Torque sensors measure the rotational force applied to the cranks, providing accurate feedback on the rider's effort. With this information the rider has optimal insights of the wattage he is delivering. By integrating strain gauges on cranks, sport and e-bike manufacturers can implement more advanced pedal-assist systems, such as torque-based pedal assistance or provide more user insights.

Torque-based pedal assistance takes into account not only the force applied by the rider but also the cadence and speed at which the pedals are turning. This sophisticated system ensures a proportional and smooth assistance delivery, matching the rider's pedaling style and cadence. As a result, riders experience a more natural and engaging riding experience, almost as if the e-bike is an extension of their own power.

Safety and Control:

Force sensors not only contribute to performance enhancements but also play a crucial role in safety and control aspects of e-bikes. By accurately measuring the force exerted on the handlebars, force sensors can detect sudden impacts or obstacles encountered during a ride. This information can be utilized to trigger safety features like anti-lock braking systems (ABS) or stability control systems, which can help prevent accidents or reduce their severity.

Furthermore, force sensors can be used in the development of smart systems that adapt the e-bike's behavior based on the rider's inputs. For example, force sensors can detect a rider's intent to make a sharp turn by measuring the applied force during handlebar input, enabling the e-bike to adjust the motor power output or steering assistance accordingly. These features provide riders with greater control and confidence, particularly in challenging or unpredictable riding conditions.