A Review of Switched Inertance Hydraulic Converter Technology1

Author(s):  
Chenggang Yuan ◽  
Min Pan ◽  
Andrew Plummer

Abstract Digital hydraulics is a new technology providing an alternative to conventional proportional or servovalve-controlled systems in the area of fluid power. Digital hydraulic applications, such as digital pumps, digital valves and actuators, switched inertance hydraulic converters (SIHCs), and digital hydraulic power management systems, promise high-energy efficiency and less contamination sensitivity. Research on digital hydraulics is driven by the need for highly energy efficient hydraulic machines but is relatively immature compared to other energy-saving technologies. This review introduces the development of SIHCs particularly focusing on the work being undertaken in the last 15 years and evaluates the device configurations, performance, and control strategies that are found in the current SIHC research. Various designs for high-speed switching valves are presented, and their advantages and limitations are compared and discussed. The current limitations of SIHCs are discussed and suggestions for the future development of SIHCs are made.

Author(s):  
Chenggang Yuan ◽  
Min Pan ◽  
Andrew Plummer

Digital hydraulics is a new technology providing an alternative to conventional proportional or servovalve-controlled systems in the area of fluid power. Research is driven by the need for highly energy efficient hydraulic machines but is relatively immature compared to other energy-saving technologies. Digital hydraulic applications, such as digital pumps, digital valves and actuators, switched inertance hydraulic converters (SIHCs) and digital hydraulic power management systems, all promise high energy efficiency. This review introduces the development of SIHCs and evaluates the device configurations, performance and control strategies that are found in current SIHC research, particularly focusing on the work being undertaken in last 15 years. The designs for highspeed switching valves are evaluated, and their advantages and limitations are discussed. This article concludes with some suggestions for the future development of SIHCs.


Author(s):  
E.D. Wolf

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.


Proceedings ◽  
2020 ◽  
Vol 64 (1) ◽  
pp. 20
Author(s):  
Paul Motzki

The versatility of the form factors of thermal shape memory alloys (SMA) in combination with their unique actuation and sensing abilities allow for the design and construction of innovative multifunctional systems. Despite the considerable number of advantages, such as their exceptional energy density, only a few SMA-based actuator systems are commercially available. One of the main reasons for this is their inefficient thermal activation and the resulting high energy consumption. The efficiency of SMA-based actuator systems can be improved by innovative design and control approaches. In the first part of this paper, the intelligent combination of SMA actuator wires with bi-stable, nonlinear spring elements is described. This combination eliminates the commonly quoted disadvantages of SMAs—slow actuation and energy inefficiency—for a wide range of applications. In particular, two energy-free actuator configurations are realized, which can be applied to any non-proportional actuation tasks. The second approach for the realization of high-speed actuation and energy efficiency is the activation of SMA wires with high voltage pulses, which leads to actuation times in the millisecond range and energy savings of up to 80% in comparison to the suppliers’ recommendations. It is shown that even high AC voltages such as typical mains supplies can be directly used for highly efficient SMA activation.


2020 ◽  
Author(s):  
Jeff Gau ◽  
Ryan Gemilere ◽  
James Lynch ◽  
Nick Gravish ◽  
Simon Sponberg ◽  
...  

AbstractCentimeter-scale fliers that combine wings with springy elements must contend with the high power requirements and mechanical constraints of flapping wing flight. Insects utilize elastic energy exchange to reduce the inertial costs of flapping wing flight and potentially match wingbeat frequencies to a mechanical resonance. Flying at resonance may be energetically favorable under steady conditions, but it is difficult to modulate the frequency of a resonant system. Evidence suggests that insects utilize frequency modulation over long time scales to adjust aerodynamic forces, but it remains an open question the extent to which insects can modulate frequency on the wingstroke-to-wingstroke timescale. If wingbeat frequencies deviate from resonance, the musculature must work against the elastic flight system, thereby potentially increasing energetic costs. To assess how insects address the simultaneous needs for power and control, we tested the capacity for wingstroke-to-wingstroke wingbeat frequency modulation by perturbing free hovering Manduca sexta with vortex rings while recording high-speed video at 2000 fps. Because hawkmoth flight muscles are synchronous, there is at least the potential for the nervous system to modulate frequency on each wingstroke. We observed ± 16% wingbeat frequency modulation in just a few wing strokes. Via instantaneous phase analysis of wing kinematics, we found that over 85% of perturbation responses required active changes in motor input frequency. Unlike their robotic counterparts that explicitly abdicate frequency modulation in favor of energy efficiency, we find that wingstroke-to-wingstroke frequency modulation is an underappreciated control strategies that complements other strategies for maneuverability and stability in insect flight.


2000 ◽  
Author(s):  
Marco Muenchhof ◽  
Timothy Hindle ◽  
Tarunraj Singh

Abstract The paper focuses on the modeling and control of a catenary-pantograph system. For the catenary system, only the contact wire is considered. Initially, the case of a constant force traveling at a constant velocity along the wire is investigated and closed form solutions are derived. Next, the pantograph dynamics are considered using a simple spring-mass-damper model, where the force is no longer assumed to be constant. The need for control in this case is apparent and motivates two different control strategies. The first control strategy utilizes a feed-forward Fourier series control profile. For the second control strategy, a proportional force feed-back control is added. All control parameters are obtained using constrained optimization techniques. Stability and sensitivity issues are addressed.


Author(s):  
N. J. M. van Dijk ◽  
E. J. J. Doppenberg ◽  
R. P. H. Faassen ◽  
N. van de Wouw ◽  
J. A. J. Oosterling ◽  
...  

High-speed milling is often used in industry to maximize productivity of the manufacturing of high-technology components, such as aeronautical components, mold, and dies. The occurrence of chatter highly limits the efficiency and accuracy of high-speed milling operations. In this paper, two control strategies are presented that guarantee a chatter-free high-speed milling operation by automatic adaptation of spindle speed and feed. Moreover, the proposed strategies are robust for changing process conditions (e.g., due to heating of the spindle or tool wear). An important part of the control strategy is the detection of chatter. A novel chatter detection algorithm is presented that automatically detects chatter in an online fashion and in a premature phase such that no visible marks on the workpiece are present. Experiments on a state-of-the-art high-speed milling machine underline the effectiveness of the proposed detection and control strategies.


Sensors ◽  
2020 ◽  
Vol 20 (19) ◽  
pp. 5600
Author(s):  
Xiaoqiang Xiang ◽  
Lili Liu ◽  
Luying Que ◽  
Conghan Jia ◽  
Bo Yan ◽  
...  

In this work, a biological retina inspired tone mapping processor for high-speed and energy-efficient image enhancement has been proposed. To achieve high throughput and high energy efficiency, several hardware design techniques have been proposed, including data partition based parallel processing with S-shape sliding, adjacent frame feature sharing, multi-layer convolution pipelining, and convolution filter compression with zero skipping convolution. Implemented on a Xilinx’s Virtex7 FPGA, the proposed design achieves a high throughput of 189 frames per second for 1024 × 768 RGB images while consuming 819 mW. Compared with several state-of-the-art tone mapping processors, the proposed design shows higher throughput and energy efficiency. It is suitable for high-speed and energy-constrained image enhancement applications.


IEEE Access ◽  
2020 ◽  
Vol 8 ◽  
pp. 116900-116913 ◽  
Author(s):  
Lingyun Shao ◽  
Ahu Ece Hartavi Karci ◽  
Davide Tavernini ◽  
Aldo Sorniotti ◽  
Ming Cheng

2012 ◽  
Vol 717-720 ◽  
pp. 1219-1224 ◽  
Author(s):  
Alexander B. Lostetter ◽  
J. Hornberger ◽  
B. McPherson ◽  
J. Bourne ◽  
R. Shaw ◽  
...  

The demands of modern high-performance power electronics systems are rapidly surpassing the power density, efficiency, and reliability limitations defined by the intrinsic properties of silicon-based semiconductors. The advantages of silicon carbide (SiC) are well known, including high temperature operation, high voltage blocking capability, high speed switching, and high energy efficiency. In this discussion, APEI, Inc. presents two newly developed high performance SiC power modules for extreme environment systems and applications. These power modules are rated to 1200V, are operational at currents greater than 100A, can perform at temperatures in excess of 250 °C, and are designed to house various SiC devices, including MOSFETs, JFETs, or BJTs.


Author(s):  
Simone Domenico Antonietta ◽  
Andrea Coluccio ◽  
Giovanna Turvani ◽  
Marco Vacca ◽  
Mariagrazia Graziano ◽  
...  

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