The type of sensor used on an electric bicycle (ebike) can vary depending on the design and features of the ebike. However, the most common type of sensor found on ebikes is a cadence sensor, which measures the rate at which the rider is pedaling and provides information to the bike’s controller to adjust the level of electrical assistance provided to the rider. Cadence sensors are relatively inexpensive and easy to install, making them a popular choice for manufacturers and riders alike. Some higher-end ebikes may also include torque sensors, which measure the amount of force the rider is applying to the pedals, providing a more natural and precise level of assistance. Speed sensors, which measure the speed of the bike, are also commonly used on ebikes to control the level of assistance provided at different speeds, but are typically not used as the primary sensor for the pedal-assist system.
1 Speed sensor
An ebike speed sensor is a device that measures the speed at which an electric bicycle (ebike) is traveling. It is a crucial component of the ebike’s electrical system as it provides information to the electric motor on how much assistance it needs to provide to the rider.
The speed sensor typically consists of a magnet attached to one of the spokes of the bike’s wheel, and a sensor mounted on the bike’s frame near the magnet. As the wheel rotates, the magnet passes by the sensor, which generates a signal that is interpreted by the bike’s control system to determine the bike’s speed.
There are two types of speed sensors commonly used in ebikes: wheel-mounted sensors and pedal-assist sensors. Wheel-mounted sensors are mounted on the wheel, and are typically found on bikes with a throttle-based system, which provides power when the throttle is engaged, regardless of how fast the pedals are turning. Pedal-assist sensors, on the other hand, are located near the bike’s crankset and measure the rotation of the pedals. They are typically found on bikes with a pedal-assist system, which provides power to the motor only when the rider is pedaling.
The accuracy of an ebike speed sensor is important, as it affects the performance of the bike’s electrical system. A properly calibrated speed sensor ensures that the motor provides the correct amount of assistance to the rider, regardless of how fast or slow the rider is traveling.
2 Cadence sensor
An ebike cadence sensor is a device that measures the rate at which a rider is pedaling on an electric bicycle (ebike). It is a critical component of the ebike’s pedal-assist system as it provides information to the bike’s controller to adjust the level of electrical assistance provided to the rider.
The cadence sensor is typically located near the bike’s crankset, where it can detect the rotational movement of the pedals. It consists of a magnet attached to the bike’s crank arm, and a sensor mounted on the bike’s frame near the magnet. As the rider pedals, the magnet passes by the sensor, which generates a signal that is interpreted by the bike’s controller to determine the rider’s pedaling speed or cadence.
The cadence sensor is designed to work in conjunction with the bike’s controller to adjust the level of electrical assistance provided to the rider. As the rider pedals faster, the controller may increase the level of assistance provided by the electric motor, and as the rider pedals slower, the controller may decrease the level of assistance provided.
The accuracy of an ebike cadence sensor is important, as it affects the overall performance of the pedal-assist system. A properly calibrated cadence sensor ensures that the motor provides the appropriate level of assistance to the rider, based on their pedaling speed, resulting in a smoother and more efficient riding experience.
Some ebikes may also include additional sensors, such as torque sensors, which measure the force that the rider is applying to the pedals. These sensors provide more precise control over the level of assistance provided by the motor and can result in a more natural and intuitive riding experience.
3 Torque sensor
An ebike torque sensor is a device that measures the amount of force a rider is applying to the pedals on an electric bicycle (ebike). It is a critical component of the ebike’s pedal-assist system as it provides information to the bike’s controller to adjust the level of electrical assistance provided to the rider in a more precise and nuanced manner than a cadence sensor.
The torque sensor is typically located in the bike’s bottom bracket or pedal assembly, where it can detect the twisting force generated by the rider as they pedal. It consists of a strain gauge, which is a device that changes its electrical resistance in response to pressure or stress, attached to the bike’s frame or pedal. As the rider applies force to the pedals, the strain gauge detects the resulting pressure or stress, and generates an electrical signal that is interpreted by the bike’s controller to determine the level of force being applied.
The torque sensor is designed to work in conjunction with the bike’s controller to adjust the level of electrical assistance provided to the rider. As the rider applies more force to the pedals, the controller may increase the level of assistance provided by the electric motor, and as the rider applies less force, the controller may decrease the level of assistance provided. This allows for a more nuanced and natural-feeling riding experience, as the level of assistance is adjusted in real-time to match the rider’s effort.
The accuracy of an ebike torque sensor is important, as it affects the overall performance of the pedal-assist system. A properly calibrated torque sensor ensures that the motor provides the appropriate level of assistance to the rider, based on the level of force they are applying to the pedals, resulting in a smoother and more efficient riding experience. However, torque sensors tend to be more expensive and less common than cadence sensors or wheel speed sensors.
Speed, cadence, and torque sensors are three types of sensors commonly used in electric bicycles (ebikes) to provide information to the bike’s controller to adjust the level of electrical assistance provided to the rider. A speed sensor measures the speed at which the bike is traveling and provides information to the bike’s control system to determine the appropriate level of assistance to provide. A cadence sensor measures the rate at which the rider is pedaling and provides information to the bike’s controller to adjust the level of assistance based on the rider’s pedaling speed. A torque sensor measures the amount of force the rider is applying to the pedals and provides information to the bike’s controller to adjust the level of assistance in a more precise and nuanced manner than a cadence sensor. While each sensor serves a different purpose, they all work together to provide a more natural and efficient riding experience for the rider.
The below video from Gazelle explained the difference between a rotation sensor and a pedal force sensor. Hoping could help for your understanding.