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 cy...

Taking a direct-drive volume control (DDVC) electro-hydraulic servo system as the research object and aiming at problems of motor torque fluctuation, high-precision pressure control, dynamic response system, based on traditional direct (DTC), method sliding-mode variable structure is proposed to pressure. The loop part inner has rapid speed, resulting in higher accuracy. A nonlinear mathematica...

This paper studies the control of an electro-hydraulic servosystem using a non-linear backstepping based approach. These systems are known to be highly non-linear due to many factors as leakage, friction and especially the fluid flow expression through the servo-valve. Another fact, often neglected or avoided, is that such systems have a non-differentiable mathematical model for bi-directional ...

As the aviation industry evolves toward nextgeneration fly-by-wire vehicles, hydraulic and electrohydrostatic actuators (EHA) are replaced with their electro-mechanical counterparts. By eliminating fluid leakage problems while reducing weight and enhancing vehicle control, the feasibility of electromechanical actuators (EMA) in avionic applications has been established. However, due to the inhe...

Abstract—Electro-hydraulic power steering (EHPS) system for the fuel rate reduction and steering feel improvement is comprised of ECU including the logic which controls the steering system and BL DC motor and produces the best suited cornering force, BLDC motor, high pressure pump integrated module and basic oil-hydraulic circuit of the commercial HPS system. Electro-hydraulic system can be stu...

Fluid pumping losses are one of the major sources of torque loss in modern Continuously Variable Transmissions (CVTs) due to the high pressures and flow rates required in the hydraulic control system. To reduce the magnitude of these losses, researchers at UC Davis have developed a servo-pump control system for CVTs designed for improved pressure and ratio controllability with minimal power con...

The main goal of the study is to analyze all relevant properties of the electro hydraulic systems and based on that to make a proper choice of the control strategy that may be used for the control of the servomechanism system. A combination of electronic and hydraulic systems is widely used since it combines the advantages of both. Hydraulic systems are widely spread because of their properties...

Nowadays, the active suspension is the key technology for vehicles to achieve both ride comfort and control performance. In this paper, a new 1/4T servo-hydraulic vehicle active suspension system is developed and two control schemes are utilized. The first one is a conventional PID controller obtained from Ziegler-Nichols method and the second one is the neural network controller. Though these ...

This paper presents a unified and systematic assessment of ten position control strategies for a hydraulic servo system with single-ended cylinder driven by a proportional directional control valve. We aim at identifying those methods that achieve better tracking, have a low sensitivity to system uncertainties, and offer a good balance between development effort and end results. A formal approa...