Multiple Simultaneous Rotation Event-Based Angular Speed Measurement

Monitoring rotating machines is essential for evaluating operations, preventing failures, and improving efficiency. Traditional rotational measurement methods, like magnetic induction or optical sensors, typically require dedicated hardware for each rotating part, making them costly and complex to implement, especially in industrial scenarios. The challenge intensifies when multiple rotations must be measured simultaneously. This study introduces a novel method using a single-event-based vision sensor, or dynamic vision sensor (DVS), which offers asynchronous pixel activation, high temporal resolution, and a wide dynamic range. Unlike traditional frame-based sensors, which require high frame rates and generate large data volumes, the DVS analyzes event streams and processes signals to identify crossing edges and time intervals. This enables simultaneous measurement of multiple rotating parts. The method was tested on a fan propeller, a CNC lathe, and drone propellers, demonstrating a relative mean absolute error (MAE) of around 0.5%. This method allows safe distance measurements without altering the original production line due to its non-contact nature.