Owing to the high power consumption and limited control precision of traditional hydraulic drive winch systems, this study proposes electric-type energy recovery systems. The accumulator used in type has low density, which makes it difficult store a large amount energy. Meanwhile, electric motor/generator cannot solve secondary slip because oil leakage, leads controllability high-power under ne...

Given the influence of flow instability, parameter uncertainty, and unpredictable disturbances in electro-hydraulic lifting systems, high-precision position control for systems is challenging to achieve. This study proposes an observer–sliding mode strategy improve accuracy tractor system. Firstly, principle hoisting system analyzed. Secondly, a mathematical model established, reduced design ob...

Hydraulic machines have been widely used in a variety of high power applications. Typically these machines are operated by an operator. In past research the interaction safety between the operator and the machine was seldom investigated. This dissertation addressess the interaction stability issue by exploiting the safety guarantees offered by passive systems. The hydraulic machine considered i...

TAbstract T— A new modeling software, AMEsim is put forward in this paper to develop a nonlinear model for a higher performance three stage electro-hydraulic servo valve. The simulation results and experimental results on existing valve are consistent, which proves that the developed model is right. The analysis of the model shows that pilot valve bandwidth mainly affects the bandwidth of three...

A range of continental-scale soil datasets exists in Europe with different spatial representation and based on different principles. We developed comprehensive pedotransfer functions (PTFs) for applications principally on spatial datasets with continental coverage. The PTF development included the prediction of soil water retention at various matric potentials and prediction of parameters to ch...

Electro-hydraulic compact drives (ECDs) are an emerging technology for linear actuation in a wide range of applications. Especially within the low power 5–10 kW, plug-and-play capability, good energy efficiency and small space requirements ECDs render this promising alternative to replace conventional valve-controlled drive solutions. In range, generally rely on passive cooling keep oil system ...

The paper deals with the characteristics of three different types power train hybridization forest logging machines and benefits reducing environmental impacts by comparing new technology more conventional, older technology. New options that could be implemented in forestry are also discussed. divides a hybrid solution into classes based on energy used system hybridization. First is an electro-...

The study is focused on an electro-hydraulic servo system which is a position control system. It is a non-minimum phase system when it was discretized with a certain sample time. To improve its tracking performance and extend its bandwidth, based on invariance principle, feed-forward compensation is developed by pole-zero placement theory for the system. The task is accomplished by transforming...

The rehabilitation exoskeleton is an effective piece of equipment for stroke patients and the aged. However, this complex human–robot system incurs many problems, such as modeling uncertainties, unknown interaction, external disturbance, actuator fault. This paper addresses adaptive fault-tolerant tracking control a lower limb joint driven by electro-hydraulic (EHA). First, model built consider...