What is a Strain Gauge?

A strain gauge is a small device that measures the strain or deformation of an object. It typically consists of a very thin wire or foil attached to the surface of the measured object. When the object is subjected to a force or strain, the wire or foil is deformed, which changes its electrical resistance.

By measuring the change in resistance, the strain gauge can determine the amount of deformation. This corresponds to the amount of force or strain that the object is experiencing.

The data obtained from a strain gauge is used for various purposes in e-bike applications. It optimizes motor assistance, detects rider input, and provides feedback for suspension systems. It also monitors the health and performance of critical components. In this way, strain gauges can contribute to e-bikes by improving electronic control systems to enhance performance, safety, and reliability.

Another advantage of using strain gauges in e-bike applications is the monitoring of the health and performance of critical components such as frame, fork, or other load-bearing parts. Without a strain gauge, the controller may not be able to detect critical issues, such as fatigue or damage to components. This could result in reduced reliability and an increased risk of failure.

Strain gauges are the heart of the torque sensor for e-bikes we develop at Sensitivus. Usually, we design torque sensor systems with more than one strain gauge and combine the information into a very accurate signal. Even extremely tiny twists on the crank – caused by the push on the pedal – will be detected immediately. The information sent to the motor controller results in a very precise output.