Feedforward compensation for target drift caused by shroud removal based on Kalman filter

In inertial confinement fusion, precise alignment between the laser and the target is crucial for the success of laser fusion experiments. The shroud, which protects the target, retracts seconds before laser shooting, a process that inadvertently induces target drift, thus compromising alignment with the laser. We established an experimental framework, employing a laser interferometer of picometric precision, to monitor the target’s displacement during the shroud’s retraction. To counteract the target drift from the shroud’s motion, we implemented a feedforward compensation strategy grounded in Kalman filter theory, which ensures the target remains within the acceptable alignment error margins relative to the target chamber center post-shroud retraction. This approach bolsters the cryogenic target system’s stability, thereby improving the likelihood of successful laser fusion ignition.