Retraction Note: Lqr-based PID controller with variable load tuned with data-driven methods for double inverted pendulum2026-03-030 PRE AI MMuhammad Shamrooz Aslam HHazrat Bilal MMohammad Hayajneh * DOI:10.1007/s00500-026-11274-2OriginalOriginal request for helpShareSaveAbstract En