Precise motion tracking and velocimetry using chirped power oscillation wave

Precise high-speed motion tracking and velocimetry are critical underlying technologies in various areas such as advanced manufacturing, robotics, and modern physics. Mature detection methods such as Doppler velocimetry and dual-comb interferometry measurements cannot achieve directional unambiguity detection without a trade-off between speed and precision due to the inherent limitations of their system mechanisms. In this study, we propose an innovative high-speed and precise motion detection method based on chirped power oscillation waves (CPOW) generated by dispersion-controlled dual-swept lasers. Our results demonstrate that the displacement and velocity of the target can be directly identified via the power oscillation of the zero-frequency point on the interference signals after carefully controlling for the difference in group delay dispersion between the two beams of the swept lasers. We achieved sub-micrometer-scale displacement measurement accuracy with an update frame rate on the order of MHz and a relative velocity measurement error of better than 0.1%. Furthermore, the proposed method can also be used to reveal the unpredictable operational states of motion-control equipment influenced by mechanical vibrations. This dynamic displacement measurement and velocimetry method based on CPOW opens the door to advanced, fast, and high-precision ranging systems.