To address the application requirements of dynamic simulation for sudden deep pavement potholes, this study presents an automated cover plate control device that integrates concealment, rapid response, and high load-bearing capacity, thereby overcoming the inherent contradiction between “portable yet weakly load-bearing” and “highly load-bearing yet inflexible” that has long limited conventional cover plate solutions. The core of the device comprises a cover plate mechanism consisting of a UHPC–Q235 composite cover plate, a distributed truss, and specially configured connecting rods, together with a winch hoisting mechanism, a hydraulic locking and rapid-release mechanism, and an embedded steel frame structure. Together, these modules realize a complete operational cycle of “closed load-bearing support → hydraulic release → gravity-driven rotation → winch reset.” Theoretical analysis and experimental measurements demonstrate that hydraulic release can be accomplished within 0.5 s, the cover plate can form a standard collapse pothole of 2000 mm in diameter within approximately 1 s, and a single cycle requires approximately 11 s, thereby faithfully reproducing the dynamic process of sudden pavement collapse. Refined mechanical design and ABAQUS finite element simulations verify that under the most adverse loading conditions, the stress in all structural components remains below the material design strength limit, with clear and reliable load transfer paths maintained in all operational states. The integrated camouflage design achieves over 95% visual and tactile similarity to the existing pavement surface, meeting the design requirement of concealment under normal conditions. The proposed device offers a high-fidelity physical simulation solution for autonomous vehicle perceptual training under emergent road hazards and for roadway safety assessment.