Analysis and research on the constant-rate penetration mechanism of the seabed cone penetration test system

The seabed Cone Penetration Test (CPT) system is a common method for investigating offshore soil. This paper focuses on new subsea CPT assessing physical and mechanical properties of marine sediments. enables automatic docking dismantling the probe rods underwater. constant-rate penetration mechanism basis core component CPT, allowing rod cone to penetrate seafloor sediment. Double hydraulic cylinders are used meet high force requirements. To maintain constant rate 20 ± 5 mm/s, model identification electro-hydraulic servo performed using Simcenter AMESim MATLAB software, relevant transfer function obtained PID method. Based this function, sliding mode variable structure controller designed regulate cylinder against varying resistance. In-situ measurements were operated rig in Zhoushan Island. simulation testing results confirm that suitable controlling during actual operation.