In this paper, a novel simple, but effective output feedback robust control (OFRC) for achieving highly accurate position tracking of pump-controlled electro-hydraulic system is presented. To cope with the unavailability all state information, an extended observer (ESO) was adopted to estimate angular velocity and load-pressure-related variable actuator total matched disturbance, which enters t...

An electrohydrostatic actuator (EHA) is a basic mechanical/hydraulic system with deficiencies including significant nonlinearity and parametric uncertainties. In line the challenges of designing high-precision control strategy, an adaptive damping variable sliding mode controller established, which extends our previous work on EHA control. The proposed integrates variable-damping control, adapt...

Events of regional-scale vegetation mortality appear to be increasing in a variety of biomes throughout the Earth and are frequently associated with increased temperatures, droughts, and often (but not always) with outbreaks of biotic agents such as insects and pathogens (for review, see Allen et al., 2010; Supplemental Information S1). The precise physiological mechanisms underlying plant mort...

Hydraulic servo system plays an important role in industrial fields due to the advantages of high response, small size-to-power ratio and large driving force. However, inherent nonlinear behaviors modeling uncertainties are main obstacles for hydraulic achieve tracking performance. To deal with these difficulties, this paper presents a backstepping sliding mode controller improve dynamic perfor...

Short-term changes in the hydraulic head of surface water bodies are known to influence the shallow response of hydraulically connected groundwaters. Associated with these fluctuations is the physical increase in stream water creating a mechanical load on the ground surface. This load is supported by the geologic materials (sediment or rock) and the pore fluid contained within the pores. Change...

Studies have shown that feedback linearization can provide an effective controller for many types of nonlinear systems. It is known, however, that these controllers are not robust, in particular to model uncertainties as the feedback linearization process involves canceling of nonlinearities in the dynamics using an exact model which is seldom available. Although there are several strategies to...

[1] Two large-scale cross-hole pumping tests were conducted at depths of 191–226 m and 662–706 m in deep boreholes at the Mizunami Underground Research Laboratory (MIU) construction site in central Japan. During these two tests, induced groundwater responses were monitored at many observation intervals at various depths in different boreholes at the site. We analyze the two cross-hole pumping t...

Realizing that generality and uniformity of the usual Soft Computing (SC) structures exclude the application of plausible simplifications relevant in the case of whole problem classes resulted in the idea that a novel branch of soft computing could be developed by the use of which far simpler and more lucid uniform structures and procedures could be applied than in the traditional ones. Such a ...