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Artykuły w czasopismach na temat "Lateral force controlled systems"
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Seo, Younghoon, Kwanghyun Cho i Kanghyun Nam. "Integrated Yaw Stability Control of Electric Vehicle Equipped with Front/Rear Steer-by-Wire Systems and Four In-Wheel Motors". Electronics 11, nr 8 (18.04.2022): 1277. http://dx.doi.org/10.3390/electronics11081277.
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This paper presents the integrated motion control method for an electric vehicle (EV) equipped with a front/rear steer-by-wire (SbW) system and four in-wheel motor (IWM). The proposed integrated motion control method aims to maintain stable cornering. To maintain vehicle agility and stability, the lateral force and yaw rate commands of the vehicle are generated by referring to the neutral steering characteristics. The driver’s driving force command, the lateral force command based on the bicycle model, and the yaw moment generated by the high-level controller are distributed into the driving force of each wheel and the lateral force of the front and rear wheels by the yaw moment distribution. Finally, the distributed forces are directly controlled by a low-level controller. To directly control the forces, a driving force observer and a lateral force observer were introduced via driving force estimation in the IWMs and rack force estimation in the SbW system. The control performance is verified through computer simulations.
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Fu, Yaomin, i Sheldon Cherry. "Simplified seismic code design procedure for friction-damped steel frames". Canadian Journal of Civil Engineering 26, nr 1 (1.02.1999): 55–71. http://dx.doi.org/10.1139/l98-043.
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This paper describes the development of a proposed seismic design procedure for friction-damped steel structures, which employs the lateral force provisions used in many modern building codes. Closed-form expressions are first derived that relate the normalized response of a single degree of freedom friction-damped system with the system parameters, such as bracing stiffness ratio, damper slip ratio, and frame member ductility. A parametric analysis is then used to reveal that the seismic displacement of a friction-damped frame can be controlled by combining the frame stiffness with the bracing stiffness of the friction damper component, while the seismic force can be controlled by the damper slip force. A force modification factor (equivalent to the code R-factor) and displacement estimate for a friction-damped system are next determined. The single degree of freedom results are subsequently used to develop expressions for dealing with the multi degree of freedom situation, which permits the seismic lateral force design procedure adopted by many current building codes to be applied to friction-damped systems. The proposed procedure allows the frame response to be controlled so that the displacement can be limited to small magnitudes and the overall structural shape to an essentially straight-line deformation. Design examples illustrate that friction-damped frame systems are economical and offer a better overall response performance than that provided by conventional systems under the design earthquake.Key words: passive energy dissipation system, friction damper, steel frame, design procedure, static analysis.
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Terashima, Kazuhiko, Takanori Miyoshi, Keisuke Mouri, Hideo Kitagawa i Panya Minyong. "Hybrid Impedance Control of Massage Considering Dynamic Interaction of Human and Robot Collaboration Systems". Journal of Robotics and Mechatronics 21, nr 1 (20.02.2009): 146–55. http://dx.doi.org/10.20965/jrm.2009.p0146.
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This paper proposes an intelligent massage control system that uses a multi-fingered robot hand with hybrid impedance control, which is able to recreate the movement and force of a human massage therapist. Therefore, various massage points, such as changes in the stiffness of human skin muscle, can be controlled by using an impedance control method. A hybrid impedance control, comprised of position-based and force-based control methods, was developed. The position-based impedance control is used to control the lateral position of massage on the human skin muscle. On the other hand, the force-based impedance control is used to control the force of the vertical direction on human skin muscle. This paper also identifies human skin muscle through robot perception of impedance to decide on the parameters of the impedance controller. A strategy using impedance control to implement an adaptive control system is presented, under the conditions of both soft and hard skin and muscle. The effectiveness of this massage control system using a multi-fingered robot hand with hybrid impedance control is demonstrated through realistic massage experiments involving pushing and rubbing motions.
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Dinarelli, Simone, Andrzej Sikora, Angela Sorbo, Marco Rossi i Daniele Passeri. "Atomic force microscopy as a tool for mechanical characterizations at the nanometer scale". Nanomaterials and Energy 12, nr 2 (1.06.2023): 1–10. http://dx.doi.org/10.1680/jnaen.23.00016.
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The design, optimization, and realization of innovative nanocomposite materials for advanced applications in a broad range of fields, from energy, automotive, photonics, to biology and nanomedicine require the capability to characterize their physical (e.g., mechanical, electric, magnetic...) properties from a multiscale perspective, in particular, not only at the macroscopic scale, but also at the nanometer one. In particular, methods are needed to characterize mechanical properties with nanometer lateral resolution, in order to understand the contribution of the nanosized features of the materials and the related phenomena. Atomic force microscopy (AFM) has been evolved from a tool for the morphological analysis of the sample surface to an integrated platform for the physicochemical characterization of samples. Current AFM systems host several advanced techniques for the mechanical characterization of materials with high speed and high lateral resolution in a broad range of mechanical moduli, e.g., from stiff samples (e.g., coatings, crystals…) to soft materials (e.g., polymers, biological samples...), in different environments (e.g., air, vacuum, liquid), and conditions (controlled humidity, controlled temperature). Here, short review of AFM based methods for the nanomechanical characterization of materials, in particular force spectroscopy, is reported, with emphasis on the materials which can be analyzed.
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Zheng, Liang, i Jun Ye. "Analysis of the Lateral Stability for Four-Wheel Independent Driving Electric Vehicles". Applied Mechanics and Materials 590 (czerwiec 2014): 394–98. http://dx.doi.org/10.4028/www.scientific.net/amm.590.394.
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The four-wheel independent driving EVs have been considered as the hot spot due to their excellent controlling capability of the driving force distribution in recent years. In order to achieve the excellent control capability of electric drive systems, the mechanical properties and performance need to be investigated and evaluated. In this paper, the lateral stability of four-wheel independent driving EVs is studied and the major factors are investigated. Results of the analysis indicate that the sideslip angle of the vehicle should be controlled at a small value. Under this condition, the yaw rate plays a key role on the lateral stability of the vehicle. The results in this research provide a solid guidance to considerably improve the lateral stability and the active safety of the EVs, in both theoretical and practical aspects.
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Volk, János, János Radó, Zsófia Baji i Róbert Erdélyi. "Mechanical Characterization of Two-Segment Free-Standing ZnO Nanowires Using Lateral Force Microscopy". Nanomaterials 12, nr 23 (22.11.2022): 4120. http://dx.doi.org/10.3390/nano12234120.
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Mechanical characterization of quasi one-dimensional nanostructures is essential for the design of novel nanoelectromechanical systems. However, the results obtained on basic mechanical quantities, such as Young’s modulus and fracture strength, show significant standard deviation in the literature. This is partly because of diversity in the quality of the nanowire, and partly because of inappropriately performed mechanical tests and simplified mechanical models. Here we present orientation-controlled bending and fracture studies on wet chemically grown vertical ZnO nanowires, using lateral force microscopy. The lateral force signal of the atomic force microscope was calibrated by a diamagnetic levitation spring system. By acquiring the bending curves of 14 nanowires, and applying a two-segment mechanical model, an average bending modulus of 108 ± 17 GPa was obtained, which was 23% lower than the Young’s modulus of bulk ZnO in the [0001] direction. It was also found that the average fracture strain and stress inside the nanowire was above 3.1 ± 0.3 % and 3.3 ± 0.3 GPa, respectively. However, the fracture of the nanowires was governed by the quality of the nanowire/substrate interface. The demonstrated technique is a relatively simple and productive way for the accurate mechanical characterization of vertical nanowire arrays.
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Rajput, Harsh Raj. "Stresses & Strains in Plate Girder with Different Bracing Systems under Combination of Loadings". International Journal for Research in Applied Science and Engineering Technology 9, nr 10 (31.10.2021): 722–28. http://dx.doi.org/10.22214/ijraset.2021.38485.
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Abstract: Lateral buckling is one of the most important factors in the design of steel plate girder. This buckling in the girder can be controlled by many methods. The most popular method is to add the intermediate bracing systems along the length of girder. The unsafely designed intermediate bracing systems can easily lead to serious consequences in the construction stage due to lateral buckling by torsion which happens rapidly and suddenly when the internal force in girder exceeds the ultimate value. Reversely, if the intermediate bracing systems are designed excessively, their specific stiffness will be larger than the required one then it is very costly in both material and installing process In the present study different types of torsional bracing systems are used in twin plate girder of span 8m. As the behavior of plate girders with different type of bracing system changes differently along the length and depth. Changing the layout of bracing systems could also make the design easy and more economical. Keywords: Cross-frame Bracings, Horizontal Bracings, Plate Girder, Finite Element Analysis
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Haghshenas-Jaryani, Mahdi. "Dynamics and Computed-Muscle-Force Control of a Planar Muscle-Driven Snake Robot". Actuators 11, nr 7 (16.07.2022): 194. http://dx.doi.org/10.3390/act11070194.
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This paper presents the dynamic formulation of an artificial-muscle-driven and computed-muscle–force control for the planar locomotion of a snake robot. The snake robot uses a series of antagonistic pneumatic artificial muscles, assembled at the joints, to generate the locomotion. Kinematics of the artificial-muscle-driven robot in the joint and Cartesian spaces was derived with respect to the muscles’ motion. The Lagrangian mechanics was employed for the formulation of the dynamic model of the robot and deriving the equations of motion. A model-based computed-muscle-force control was designed to track the desired paths/trajectories in Cartesian space. The feedback linearization method based on a change of coordinate was utilized to determine an equivalent linear (input-to-state) system. Then, a full state feedback control law was designed, which satisfies the stability and tracking problems. The performance of the dynamic model and the controller were successfully demonstrated in simulation studies for tracking a circle-shape path and a square-shape path with a constant linear velocity while generating the lateral undulation gait. The results indicate a low magnitude of tracking errors where the controlled muscle force are bounded to the actual pneumatic artificial muscle’s limitations.
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Thompson, J. Michael T. "Advances in Shell Buckling: Theory and Experiments". International Journal of Bifurcation and Chaos 25, nr 01 (styczeń 2015): 1530001. http://dx.doi.org/10.1142/s0218127415300013.
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In a recent feature article in this journal, coauthored by Gert van der Heijden, I described the static-dynamic analogy and its role in understanding the localized post-buckling of shell-like structures, looking exclusively at integrable systems. We showed the true significance of the Maxwell energy criterion load in predicting the sudden onset of "shock sensitivity" to lateral disturbances. The present paper extends the survey to cover nonintegrable systems, such as thin compressed shells. These exhibit spatial chaos, generating a multiplicity of localized paths (and escape routes) with complex snaking and laddering phenomena. The final theoretical contribution shows how these concepts relate to the response and energy barriers of an axially compressed cylindrical shell. After surveying NASA's current shell-testing programme, a new nondestructive technique is proposed to estimate the "shock sensitivity" of a laboratory specimen that is in a compressed metastable state before buckling. A probe is used to measure the nonlinear load-deflection characteristic under a rigidly applied lateral displacement. Sensing the passive resisting force, it can be plotted in real time against the displacement, displaying an equilibrium path along which the force rises to a maximum and then decreases to zero: having reached the free state of the shell that forms a mountain-pass in the potential energy. The area under this graph gives the energy barrier against lateral shocks. The test is repeated at different levels of the overall compression. If a symmetry-breaking bifurcation is encountered on the path, computer simulations show how this can be suppressed by a controlled secondary probe tuned to deliver zero force on the shell.
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Switkes, Joshua P., Eric J. Rossetter, Ian A. Coe i J. Christian Gerdes. "Handwheel Force Feedback for Lanekeeping Assistance: Combined Dynamics and Stability". Journal of Dynamic Systems, Measurement, and Control 128, nr 3 (21.11.2005): 532–42. http://dx.doi.org/10.1115/1.2229256.
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Lanekeeping assistance could save thousands of lives each year by maintaining lane position in the absence of driver steering commands. In order to work smoothly with the driver, handwheel force feedback must be an integral part of such a system. Here we combine force feedback with a lanekeeping controller based on lateral and heading error. In addition to force feedback replicating the feel in a conventional vehicle, the force can be based on the level of lanekeeping assistance being given. This coupling of the force feedback and assistance systems can destabilize the vehicle if not designed properly. Linear modeling verified by experiments shows the effect of varying the gains on both the force feedback and the lanekeeping assistance itself. In this analysis we show that within a range of values that feel reasonable to the driver, changes to the lanekeeping controller or force feedback can have marked effects on the response of the vehicle. It also shows that stability of the system can be ensured by injecting artificial damping or reproducing the on-center characteristics of a conventional vehicle. The analysis allows the force feedback designer to determine a range of stable force feedback gains, from which a set most acceptable to the driver can be chosen.
Rozprawy doktorskie na temat "Lateral force controlled systems"
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Buell, Grant. "Comparison of structural steel lateral force resisting systems for a theoretical hospital grid system". Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/2321.
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Black, Rebecca Eileen. "Large-Scale Testing of Low-Strength Cellular Concrete for Skewed Bridge Abutments". BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7708.
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Low-strength cellular concrete is a type of controlled low-strength material (CLSM) which is increasingly being used for various modern construction applications. Benefits of the material include its ease of placement due to the ability of cellular concrete to self-level and self-compact. It is also extremely lightweight compared to traditional concrete, enabling the concrete to be used in fill applications as a compacted soil would customarily be used. Testing of this material is not extensive, especially in the form of large-scale tests. Additionally, effects of skew on passive force resistance help to understand performance of a material when it is used in an application where skew is present. Two passive force-deflection tests were conducted in the structures lab of Brigham Young University. A 4-ft x 4-ft x 12-ft framed box was built with a steel reaction frame on one end a 120-kip capacity actuator on the other. For the first test a non-skewed concrete block, referred to as the backwall, was placed in the test box in front of the actuator. For the second test a backwall with a 30° skew angle was used. To evaluate the large-scale test a grid was painted on the concrete surface and each point was surveyed before and after testing. The large-scale sample was compressed a distance of approximately three inches, providing a clear surface failure in the sample. The actuator provided data on the load applied, enabling the creation of the passive force-deflection curves. Several concrete cylinders were cast with the same material at the time of pouring for each test and tested periodically to observed strength increase.The cellular concrete for the 0° skew test had an average wet density of 29 pounds per cubic foot and a 28-day compressive strength of 120 pounds per square inch. The cellular concrete for the 30° skew test had an average wet density of 31 pounds per cubic foot and a 28-day compressive strength of 132 pounds per square inch. It was observed from the passive force deflection curves of the two tests that skew decreased the peak passive resistance by 29%, from 52.1 kips to 37 kips. Various methods were used to predict the peak passive resistance and compared with observed behavior to verify the validity of each method.
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Grusenmeyer, Eric. "Design comparison of ordinary concentric brace frames and special concentric brace frames for seismic lateral force resistance for low rise buildings". Kansas State University, 2012. http://hdl.handle.net/2097/14986.
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Master of ScienceDepartment of Architectural Engineering
Kimberly Waggle Kramer
Braced frames are a common seismic lateral force resisting system used in steel structures. Ordinary concentric braced frames (OCBFs) and special concentric braced frames (SCBFs) are two major types of frames. Brace layouts vary for both OCBFs and SCBFs. This report examines the inverted-V brace layout which is one common arrangement. OCBFs are designed to remain in the elastic range during the design extreme seismic event. As a result, OCBFs have relatively few special requirements for design. SCBFs are designed to enter the inelastic range during the design extreme seismic event while remaining elastic during minor earthquakes and in resisting wind loads. To achieve this, SCBFs must meet a variety of stringent design and detailing requirements to ensure robust seismic performance characterized by high levels of ductility. The design of steel seismic force resisting systems must comply with the requirements of the American Institute of Steel Construction’s (AISC) Seismic Provisions for Structural Steel Buildings. Seismic loads are determined in accordance with the American Society of Engineers Minimum Design Loads for Buildings and Other Structures. Seismic loads are very difficult to predict as is the behavior of structures during a large seismic event. However, a properly designed and detailed steel structure can safely withstand the effects of an earthquake. This report examines a two-story office building in a region of moderately high seismic activity. The building is designed using OCBFs and SCBFs. This report presents the designs of both systems including the calculation of loads, the design of frame members, and the design and detailing of the connections. The purpose of this report is to examine the differences in design and detailing for the two braced frame systems.
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Remund, Tyler Kirk. "Large-Scale Testing of Low-Strength Cellular Concrete for Skewed Bridge Abutments". BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/7213.
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Low-strength cellular concrete consists of a cement slurry that is aerated prior to placement. It remains a largely untested material with properties somewhere between those of soil, geofoam, and typical controlled low-strength material (CLSM). The benefits of using this material include its low density, ease of placement, and ability to self-compact. Although the basic laboratory properties of this material have been investigated, little information exists about the performance of this material in the field, much less the passive resistance behavior of this material in the field.In order to evaluate the use of cellular concrete as a backfill material behind bridge abutments, two large-scale tests were conducted. These tests sought to better understand the passive resistance, the movement required to reach this resistance, the failure mechanism, and skew effects for a cellular concrete backfill. The tests used a pile cap with a backwall face 5.5 ft (1.68 m) tall and 11 ft (3.35 m) wide. The backfill area had walls on either side running parallel to the sides of the pile cap to allow the material to fail in a 2D fashion. The cellular concrete backfill for the 30° skew test had an average wet density of 29.6 pcf (474 kg/m3) and a compressive strength of 57.6 psi (397 kPa). The backfill for the 0° skew test had an average wet density of 28.6 pcf (458 kg/m3) and a compressive strength of 50.9 psi (351 kPa). The pile cap was displaced into the backfill area until failure occurred. A total of two tests were conducted, one with a 30° skew wedge attached to the pile cap and one with no skew wedge attached.It was observed that the cellular concrete backfill mainly compressed under loading with no visible failure at the surface. The passive-force curves showed the material reaching an initial peak resistance after movement equal to 1.7-2.6% of the backwall height and then remaining near this strength or increasing in strength with any further deflection. No skew effects were observed; any difference between the two tests is most likely due to the difference in concrete placement and testing.
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Burgos, Ganuza Erick Antonio. "Seismic behavior of hybrid lateral-force-resisting systems". 2006. http://proquest.umi.com/pqdweb?did=1203570601&sid=1&Fmt=2&clientId=39334&RQT=309&VName=PQD.
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Thesis (M.S.)--State University of New York at Buffalo, 2006.Title from PDF title page (viewed on Feb. 22, 2007) Available through UMI ProQuest Digital Dissertations. Thesis adviser: Whittaker, Andrew S. Includes bibliographical references.
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PENSALFINI, SARA. "Long-range forces in controlled systems". Doctoral thesis, 2019. http://hdl.handle.net/11573/1244940.
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This thesis investigates new phenomena due to long-range forces and their effects
on different multi-DOFs systems. In particular the systems considered are metamaterials,
i.e. materials with long-range connections. The long-range connections
characterizing metamaterials are part of the more general framework of non-local
elasticity.
In the theory of non-local elasticity, the connections between non-adjacent particles
can assume different configurations, namely one-to-all, all-to-all, all-to-all-limited,
random-sparse and all-to-all-twin. In this study three aspects of the long-range
interactions are investigated, and two models of non-local elasticity are considered:
all-to-all and random-sparse.
The first topic considers an all-to-all connections topology and formalizes the mathematical
models to study wave propagation in long-range 1D metamaterials. Closed
forms of the dispersion equation are disclosed, and a propagation map synthesizes
the properties of these materials which unveil wave-stopping, negative group velocity,
instability and non-local effects. This investigation defines how long-range
interactions in elastic metamaterials can produce a variety of new effects in wave
propagation.
The second one considers an all-to-all connections topology and aims to define an
optimal design of the long-range actions in terms of spatial and intensity distribution
to obtain a passive control of the propagation behavior which may produces
exotic effects. A phenomenon of frequency filtering in a confined region of a 1D
metamaterial is obtained and the optimization process guarantees this is the best
obtainable result for a specific set of control parameters.
The third one considers a random-sparse connections topology and provides a new
definition of long-range force, based on the concept of small-world network. The
small-world model, born in the field of social networks, is suitably applied to a
regular lattice by the introduction of additional, randomly selected, elastic connections
between different points. These connections modify the waves propagation
within the structure and the system exhibits a much higher propagation speed and
synchronization. This result is one of the remarkable characteristics of the defined
long-range connections topology that can be applied to metamaterials as well as
other multi-DOFs systems. Qualitative experimental results are presented, and a
preliminary set-up is illustrated.
To summarize, this thesis highlights non-local elastic structures which display unusual
propagation behaviors; moreover, it proposes a control approach that produces
a frequency filtering material and shows the fast propagation of energy within a
random-sparse connected material.
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Yang, Fei-Lung, i 楊飛龍. "Study on the integrated control of force and energy-saving control for hydraulic valve controlled cylinder systems". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/32719870403207523837.
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博士國立臺灣大學
工程科學及海洋工程學研究所
92
The objective of this research is to implement a novel parallel control of the force and the energy-saving in the hydraulic valve-controlled cylinder systems(HVCCS) for simultaneously achieving accurate force control response and high energy efficiency. In order to verify the feasibility of the integrated control system and compare the energy-saving effects, the force control(FC) of the HVCCS can be integrated with two different energy-saving control(ESC) systems, as well as integrating it with a conventional hydraulic system without energy-saving control. In this study, two different kinds of control algorithm are proposed to realize the integrated control of HVCCS. First, a decoupling self-organizing fuzzy sliding-mode control (DSOFSMC) strategy, which can reduce the fuzzy rule numbers and counteract the coupling effects, is developed for the integrated control of HVCCS. Then an H∞ control algorithm, which can perform good disturbance rejection, is implemented to the concurrent control in the HVCCS. The experimental results show the outstanding performance of the parallel control in the controlled system with the two proposed controllers. In comparison with conventional valve-controlled systems, the integrated control system with the proposed algorithms can also achieve better force control responses and significant energy-saving effect at the same time.
Książki na temat "Lateral force controlled systems"
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Emre, Ilgin Hüseyin, red. Tall buildings: Structural systems and aerodynamic form. London: Routledge, Taylor & Francis Group, 2014.
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Army, United States, red. Financial management: Army conventional ammunition production not effectively accounted for or controlled : report to the Secretary of the Army. Washington, D.C: The Office, 1992.
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Office, General Accounting. Financial management: Army conventional ammunition production not effectively accounted for or controlled : report to the Secretary of the Army. Washington, D.C: The Office, 1992.
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Schutter, Joris de, Tine Lefebvre i Herman Bruyninckx. Nonlinear Kalman Filtering for Force-Controlled Robot Tasks. Springer Berlin / Heidelberg, 2010.
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Nonlinear Kalman Filtering for Force-Controlled Robot Tasks (Springer Tracts in Advanced Robotics). Springer, 2005.
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Dowding, Keith. Social and Political Power. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228637.013.198.
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Power is a complex topic that is viewed in entirely different ways by different writers. Power can be seen as a property of agents, with some agents having more power than others. It can be seen as a property of social systems, where structures hold power. It can also be seen in terms of specific actions by people to coerce or dominate, or it can be regarded as a subliminal force that leads people to think and behave in one way rather than another. It can be analyzed descriptively to try to explain how it is distributed, and critically to argue for changing structures to provide a more egalitarian and fairer distribution.Power studies flourished in the great community power studies of the 1950s and 1960s. Some of these works suggested that democratic nations were controlled by powerful elites who ruled in their own interests; some that power was more widely distributed and elites could not simply rule for themselves; others that in capitalist societies, despite some counterexamples, elites generally ruled in favor of developers and capitalists. Later studies examined how people’s interests are defined in terms of the structural positions in which they find themselves, and how the very ways in which we think and express ourselves affect our individual powers.
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Ilgin, Hüseyin Emre, i Mehmet Halis Günel. Tall Buildings: Structural Systems and Aerodynamic Form. CRC Press LLC, 2014.
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Ilgin, Hüseyin Emre, i Mehmet Halis Günel. Tall Buildings: Structural Systems and Aerodynamic Form. CRC Press LLC, 2014.
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Ablavsky, Gregory. Federal Ground. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780190905699.001.0001.
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Federal Ground depicts the haphazard and unplanned growth of federal authority in the Northwest and Southwest Territories, the first U.S. territories established under the new territorial system. The nation’s foundational documents, particularly the U.S. Constitution and the Northwest Ordinance, placed these territories under sole federal jurisdiction and established federal officials to govern them. But, for all their paper authority, these officials rarely controlled events or dictated outcomes. In practice, power in these contested borderlands rested with the regions’ preexisting inhabitants—diverse Native peoples, French villagers, and Anglo-American settlers. These residents nonetheless turned to the new federal government to claim ownership, jurisdiction, protection, and federal money, seeking to obtain rights under federal law. Two areas of governance proved particularly central: contests over property, where plural sources of title created conflicting land claims, and struggles over the right to use violence, in which customary borderlands practice intersected with the federal government’s effort to establish a monopoly on force. Over time, as federal officials improvised ad hoc, largely extrajudicial methods to arbitrate residents’ claims, they slowly insinuated federal authority deeper into territorial life. This authority survived even after the former territories became Ohio and Tennessee: although new states spoke a language of equal footing and autonomy, statehood actually offered former territorial citizens the most effective way yet to make claims on the federal government. The federal government, in short, still could not always prescribe the result in the territories, but it set the terms and language of debate—authority that became the foundation for later, more familiar and bureaucratic incarnations of federal power.
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Financial management: Army conventional ammunition production not effectively accounted for or controlled : report to the Secretary of the Army. Washington, D.C: The Office, 1992.
Znajdź pełny tekst źródłaCzęści książek na temat "Lateral force controlled systems"
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Mizuno, Takeshi, i Toshiro Higuchi. "Structure of Magnetic Bearing Control System for Compensating Unbalance Force". W Dynamics of Controlled Mechanical Systems, 135–46. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-83581-0_11.
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Campion, Gianni. "Roughness of Virtual Textures and Lateral Force Modulation". W Springer Series on Touch and Haptic Systems, 129–36. London: Springer London, 2008. http://dx.doi.org/10.1007/978-0-85729-576-7_8.
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Lefebvre, Tine, Herman Bruyninckx i Joris De Schutter. "4 Kalman Filters for Nonlinear Systems". W Nonlinear Kalman Filtering for Force-Controlled Robot Tasks, 51–76. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/11533054_4.
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Lin, Hsien-I., i Vipul Dubey. "Design of an Adaptive Force Controlled Robotic Polishing System Using Adaptive Fuzzy-PID". W Intelligent Autonomous Systems 15, 825–36. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-01370-7_64.
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Henkel, Jenny S., David R. Beers, Weihua Zhao i Stanley H. Appel. "Reactive Oxygen and Nitrogen Species – A Driving Force in Amyotrophic Lateral Sclerosis". W Systems Biology of Free Radicals and Antioxidants, 3141–65. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-30018-9_131.
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Astaneh-Asl, Abolhassan. "Steel and Composite Shear Walls - Two High-Performance Lateral Force Resisting Systems". W Lecture Notes in Civil Engineering, 3–21. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-03811-2_1.
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Parzer, Herbert, Hubert Gattringer, Matthias Neubauer, Andreas Müller i Ronald Naderer. "On Impact Behavior of Force Controlled Robots in Environments with Varying Contact Stiffness". W Computer Aided Systems Theory – EUROCAST 2015, 698–705. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-27340-2_86.
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Salvatori, Carlotta, Diego Trucco, Ignazio Niosi, Leonardo Ricotti i Lorenzo Vannozzi. "A Novel Steerable Catheter Controlled with a Biohybrid Actuator: A Feasibility Study". W Biomimetic and Biohybrid Systems, 378–93. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-39504-8_26.
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AbstractTargeted therapies allow increasing the efficacy of treatments for several diseases, including cancer. The release of drugs or chemicals directly in the site of interest will be beneficial for maximizing the therapy and minimize side effects.Here, we report the concept and a preliminary analysis of an innovative intravascular steerable catheter guided by an on-board biohybrid actuator, aiming to release drugs into deep and tortuous regions within the cardiovascular systems. The catheter performance has been estimated through analytical and numerical analyses, varying catheter diameter, wall thickness, and actuator force. Results show how larger catheter deflections can be obtained with a smaller outer diameter and decreasing wall thickness. Besides, improved outcomes can be achieved by applying the biohybrid actuator distant from the catheter tip extremity and maximizing the magnitude of the applied forces. Despite the need to further improve the performance of this concept (e.g., by decreasing material stiffness), these preliminary results show great promise in view of future experimentation of such kind of actuation to drive microcatheters through the cardiovascular network.
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Artemiadis, Panagiotis K., i Kostas J. Kyriakopoulos. "EMG-Based Position and Force Estimates in Coupled Human-Robot Systems: Towards EMG-Controlled Exoskeletons". W Experimental Robotics, 241–50. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-00196-3_29.
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Gölz, Jacqueline, i Christian Hatzfeld. "Sensor Design". W Springer Series on Touch and Haptic Systems, 431–516. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-04536-3_10.
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AbstractMultiple sensors are applied in haptic devices designs. Even if they are not closed-loop controlled in a narrow sense of force or torque generation, they are used to detect movement ranges and limits or the detection of the presence of a user and its type of interaction with an object or human-machine-interface (HMI). Almost any type of technical sensor had been applied in the context of haptic devices. The emerging market of gesture based user interaction and integration of haptics due to ergonomic reasons extends the range of sensors potentially relevant for haptic devices. However, what exactly is a sensor? Which is the right one for your purpose and is there a systematic way to choose it? To support you answering these fundamental questions, classification of sensors is helpful. This chapter starts with a definition and classifications according to measurand and sensing principles. Constraints, you will have to focus on, are discussed and selection criteria are deduced. An introduction in technologies and design principles for mechanical sensors serves as an overview for your selection process. Common types of force/torque, positioning, velocity and acceleration sensors are presented. Furthermore, imaging and temperature sensors are addressed briefly in this section.
Streszczenia konferencji na temat "Lateral force controlled systems"
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Gerard, Mathieu, Matteo Corno, Michel Verhaegen i Edward Holweg. "Force-Based ABS Control Using Lateral Force Measurement". W ASME 2011 Dynamic Systems and Control Conference and Bath/ASME Symposium on Fluid Power and Motion Control. ASMEDC, 2011. http://dx.doi.org/10.1115/dscc2011-5939.
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In this paper a hybrid force-based Anti Locking Braking System (ABS) is presented. The proposed control system directly considers the lateral tyre behaviour during heavy braking. In this way it is possible to guarantee drivability and stability also when braking on surfaces without a clear tyre characteristic peak. The goal of the paper is to show the potentialities of load-based vehicle dynamics control. It is shown that, thanks to the availability of the lateral and longitudinal tyre force measurements, a stable braking can be achieved with a minimal increase of complexity of the algorithm in conditions that are critical for traditional ABS. The general control concept is that of reducing the longitudinal slip if the measured lateral force is smaller than a desired minimum. Two different ways of computing the minimum lateral forces are presented: one for the front axle with the objective of guaranteeing steerability and one for the rear axle to guarantee stability. Simulations on a nonlinear vehicle simulator confirm that the controller can maintain the desired steering behaviour and vehicle yaw stability in case of heavy braking.
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Eyvazian, A., M. Shakeri i M. Zarei Mahmoudabadi. "Experimental Study of Corrugated Tubes Under Lateral Loading". W ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2010. http://dx.doi.org/10.1115/esda2010-24782.
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The protection of structures under impact loading often necessitates the need for energy absorbers; devices designed to absorb the impact energy in a controlled manner and hence, protect the structure under consideration. Thin-walled tubes are widely used as energy absorbers in various vehicles and moving parts. The objective of the present study is to investigate the energy absorption characteristic of tubes with corrugations in different geometries, in lateral direction. In order to produce corrugations, an innovative solution is introduced. Corrugations can be very easily generated on the surface of cylindrical aluminum tubes by stamping method. Corrugations with different wavelengths and amplitudes can be produced by this method. Experimental tests are conducted to study the effect of changing corrugation geometry (type and amplitude). Quasi-static tests are carried out whose results for lateral compression show that tubes with corrugation have a higher mean crushing force and this force is directly proportional to number of corrugations and their amplitude. Moreover, it is observed that corrugated tubes can absorb approximately four times more energy than tubes without corrugations, in the same size and weight. Finally, considering the experimental tests, corrugated tubes are shown to be more effective in lateral direction as an energy absorber, and they also exhibit desirable force-deflection responses which are important in the design of energy absorbing devices.
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Majumder, Gargi, i Rajiv Tiwari. "Vibration Control of Spur Geared Rotor Systems With Transmission Errors by Active Magnetic Bearings". W ASME 2019 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/detc2019-97176.
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Abstract Dynamic forces between the mating gears are generated due to the mesh deformation, gear eccentricities, transmission error, and gear run-out, which cause excessive vibration and noise. Study and control of these forced vibrations in gear box are vital to prevent any adverse effects on the gears and its supporting structures. Hence, this work presents a novel concept of active vibration control by introducing Active Magnetic Bearings (AMBs) on the shaft of a spur gearbox having conventional bearings as well. The AMB suppresses the response of the system by generating controlled electromagnetic forces based on the gear shaft vibration measurement. The AMB force is applied without any physical contact as opposed to mechanical forces in conventional bearings. A coupled torsional-lateral vibration analysis has been simulated with the effects of mesh deformation, gear eccentricities, transmission error, and gear run-out. The electromagnetic actuator is designed in such a way that a resultant radial control force can be developed with the help of forces in two mutually perpendicular directions. With a feedforward PID controller, the transverse vibration amplitude is observed to be suppressed to a considerable level. The frequency domain analysis is done using a full spectrum, which shows that multiple harmonics of gear mesh frequency is minimized simultaneously.
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Chee, Jayden, Alastair Walker i David White. "Effect of Lateral Pipe-Soil Interaction on Controlled Lateral Buckling Using Pre-Deformed Pipeline". W ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-77154.
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A novel approach to eliminate the onset of global buckling in pipelines is investigated in the paper. The method is based on pre-deforming a pipeline continuously with a specific wavelength and amplitude prior to installation on the seabed. The response of the pipeline to applied high temperature and pressure was studied in conjunction with variations in the lateral pipe-soil interaction (PSI) — both as uniform friction along the pipe and also with locally varying friction. Pipe and seabed parameters representing a typical wet-insulated infield flow line on soft clay are used. The pre-deformed pipeline has a higher buckle initiation temperature compared to a straight pipeline due to the reduced effective axial force build-up resulting from the low axial stiffness generated by the pre-deformed lobes along the pipeline. The results from this paper show that the strains in the pre-deformed pipeline are not significantly affected by the local variability of lateral PSI but rather by the global mean PSI. At a typical lateral soil resistance, i.e. a friction coefficient of 0.5, lateral buckling occurs at a very high temperature level that is not common in the subsea operation. At a very low friction, i.e. 0.1, lateral buckling occurs at a lower operating temperature but the strain is insignificant. The longitudinal strain of the pipeline is not highly sensitive to the lateral PSI, which is a quite different response to an initially straight pipeline. Therefore, this method could prove to be a valuable tool for the subsea industry as it enables the pipeline to be installed and operated safely at very high temperatures without the need for lateral buckling design and installation of expensive structures as buckle initiators. Even if the pre-deformed pipeline buckles at a very high temperature, during cycles of heat-up and cool-down the buckle shape ‘shakes down’ by geometric rearrangement to minimize the energy, and in doing so creates a series of ‘short pipelines’ in which the longitudinal strain is self-controlled. The system is therefore shown to be very robust in the conditions investigated and not affected by one of the biggest unknowns in seabed pipeline engineering, which is the local variability in lateral PSI.
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Temiz, Ozan, Melih Cakmakci i Yildiray Yildiz. "A Fault Tolerant Vehicle Stability Control Using Adaptive Control Allocation". W ASME 2018 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/dscc2018-8976.
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This paper presents an integrated fault-tolerant adaptive control allocation strategy for four wheel frive - four wheel steering ground vehicles to increase yaw stability. Conventionally, control of brakes, motors and steering angles are handled separately. In this study, these actuators are controlled simultaneously using an adaptive control allocation strategy. The overall structure consists of two steps: At the first level, virtual control input consisting of the desired traction force, the desired moment correction and the required lateral force correction to maintain driver’s intention are calculated based on the driver’s steering and throttle input and vehicle’s side slip angle. Then, the allocation module determines the traction forces at each wheel, front steering angle correction and rear steering wheel angle, based on the virtual control input. Proposed strategy is validated using a non-linear three degree of freedom reduced two-track vehicle model and results demonstrate that the vehicle can successfully follow the reference motion while protecting yaw stability, even in the cases of device failure and changed road conditions.
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Rossetter, Eric J., i J. Christian Gerdes. "Performance Guarantees for Hazard Based Lateral Vehicle Control". W ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32153.
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Today’s vehicles are incorporating many advanced driver assistance systems and in the near future it will be likely to have increased capabilities such as lanekeeping assist systems. These systems will be an integral part of the driving experience, aiding the driver in avoiding hazardous obstacles. One approach for these systems is to represent the hazards as artificial potential fields that add control inputs to move the vehicle towards safe regions on the road. This paper focuses on bounding the lateral motion of a vehicle for a lanekeeping system. A Lyapunov approach is used where the bounding function consists of the artificial potential energy associated with the controller, the kinetic energy in the lateral and yaw modes, and energy terms that are dependent on vehicle heading. In order to achieve this bound, a condition has to be met for the lookahead distance and the location of the control force (which can also be interpreted as a condition on the decoupling of lateral and yaw modes). Using this bound, a potential field gain can be chosen to guarantee collision avoidance with fixed lateral obstacles.
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Guan, Li, Andrew Niedert i Richard C. Hill. "Simulation-Based Design of the Geometry and Control System for an Omnidirectional Ground Vehicle". W ASME 2014 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/dscc2014-5951.
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This paper describes the simulation-based design of a teleoperated, omnidirectional ground vehicle. The multi-body dynamic simulation employed is developed in the Simulink environment, specifically employing the Simscape extension of Simulink. The accuracy of the simulation is validated by comparison to data taken from one physical instantiation of the vehicle. The use of simulation allows controlled and rapid “testing” of various configurations of the vehicle without requiring any new construction and without endangering physical hardware. The simulation also provides estimates of quantities, like road force and inertial position, that are difficult to measure. The elements of the vehicle design that are specifically investigated in this paper are the vehicle’s physical geometry and its control system. The design of the vehicle’s control system is challenging because of nonlinearities and uncertainty in the model and because it is desired to control three tightly-coupled outputs (longitudinal, lateral, and angular velocity) via six different inputs (force generated at each of the vehicle’s six wheels).
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Morscheck, Luke A., i John J. Roller. "Stress Testing of a New North American Passenger Locomotive Truck Frame in Accordance With International Union of Railways (UIC) Code". W 2013 Joint Rail Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/jrc2013-2426.
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MotivePower Incorporated (MPI) a Wabtec company and CTLGroup have completed stress testing of a new two-axle passenger locomotive truck (bogie) frame for use in North America. Testing was performed in accordance with International Union of Railways (UIC) Code 615-4 – Bogie Frame Structural Strength Tests [1]. Static testing was performed to simulate exceptional, main in-service and particular in-service loads. A three-phase dynamic fatigue test of 10 million cycles was also performed. Factors for quasi-static, dynamic and track twist (warp) loads were increased from those recommended by the UIC Code for normal operating conditions on European railways to represent North American track conditions. Significant engineering thought was invested in fixture design, with each load application and reaction point receiving careful consideration. Static testing required ten different servo-controlled loading systems to simulate independent or superimposed vertical, lateral and/or longitudinal forces. The applied loads represented tractive effort, braking effort, curving, vehicle lateral dynamics, vehicle vertical dynamics and track twist. Fatigue testing required four different servo-controlled loading systems utilizing synchronized force functions to simulate alternating quasi-static and dynamic load sequences. The apparatus also included provisions for measuring vertical reactions at each primary spring pocket. Vertical reaction loads were measured by instrumented pedestals using a full Wheatstone bridge configuration to cancel out longitudinal and lateral load effects. Prior to testing, the prototype truck frame was instrumented with 133 strain gages installed at selected points of interest. Stress values discerned from the measured strains conformed to the allowable stress criteria and compared well with those predicted by finite element analysis. Measured force reactions also showed strong correlation with predicted values. No indications of cracks were discovered during periodic non-destructive inspections. In conclusion, the UIC Code 615-4 test protocol was utilized to successfully demonstrate the strength and durability of a new two-axle passenger locomotive truck frame.
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Carden, Eoin Peter, i Stefano Morosi. "Operational Modal Analysis of Lateral Rotordynamic Modes of Rotating Machinery". W ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26308.
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The lateral rotordynamic response of turbomachinery is typically speed dependent due to hydrodynamic lubricated bearings, seals, gyroscopic and centrifugal effects, etc. Rotordynamic tools are used to predict the behavior of the machine during operation, however validating these results is challenging. Traditional experimental modal testing techniques rely on controlled and measured excitation together with measured responses. However, during operation this is unpractical, as the actual excitation force is rarely known. Operational modal analysis (OMA) can identify the modal parameters of a system over its entire operational range from measurement of response due to some (unknown) excitation. OMA has proven successful on non-rotating structures, but has seldom been applied to rotating machinery. Three case studies are presented demonstrating the use of OMA in identifying lateral rotors modes based on measurements from existing radial proximity probes during normal production undertaken as part of commissioning campaigns. Challenges encountered in using and interpreting OMA results are discussed. The results show that proximity probe data acquired during normal operation may be used as input to OMA for the assessment of stability margins of rotating machinery, to produce experimentally derived Campbell diagrams and to identify backwards as well as forwards whirling modes.
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Podder, Tarun K., Parsaoran Hutapea, Kurosh Darvish, Adam Dicker i Yan Yu. "Smart Needling System for Fully Conformal Radiation Dose Delivery in Treating Prostate Cancer". W ASME 2010 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2010. http://dx.doi.org/10.1115/smasis2010-3919.
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The objective of the project is to design a new distributed actuation system along the needle’s body (active/smart needling), exploiting the steering advantage of the bevel-tip geometry (bevel angle), developing a flexible needle body having sensors at the needle tip and along the body for real-time tracking/detection of the needle using a feedback closed-loop control for real-time steering of the needle toward the target. We present two types of needle design and actuation techniques: Longitudinal Body Segment (LoBS) design, and Lateral Body Segment (LaBS) design. For LoBS design, the needle is separated into multiple segments along its length to improve maneuverability of the needle tip. This device incorporates four Nitinol wires per segment about its tubular substructure. The ends of each wire are secured to steel anchors, which are attached to non-conducting collets. The displacement and the speed of actuation is a function of the power supplied to each Nitinol wire. The amount of power is controlled using Pulse Width Modulation. Bending in arbitrary directions can be accomplished by adjusting the electrical duty cycles of the Nitinol wires. For LaBS design, the needle body is made of Nitinol having lateral segments (two or multiple of paired segments along the needle length). Each segment is an actuator made of Nitinol, which will be capable of manipulating the needle tip according to the sensory feedback information. The distal end of the actuator segments of the needle body are hinged at different points when the needle needs to be curved down the needle body segment can be actuated so that force which will produce moment about the opposite point. Therefore, by manipulating the force the amount of needle curvature can be controlled. By rotating the needle at desired angle, any needle trajectory can be achieved for reaching the target while avoiding obstacles (or critical organ) and conforming organ geometry.
Raporty organizacyjne na temat "Lateral force controlled systems"
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Andrawes, Bassem, Ernesto Perez Claros i Zige Zhang. Bond Characteristics and Experimental Behavior of Textured Epoxy-coated Rebars Used in Concrete Bridge Decks. Illinois Center for Transportation, styczeń 2022. http://dx.doi.org/10.36501/0197-9191/22-001.
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The deterioration of bridge decks is a problem typically associated with the corrosion of the reinforcing steel. This issue was partially controlled during the 1970s with the incorporation of the epoxy-coating protection system. However, research later demonstrated that the smooth surface resulting from the epoxy-coating application reduces most of the friction between the rebar and the surrounding concrete. Consequently, forces acting on the rib faces are reconfigured in such a way that the radial components increase, triggering the early development of cracks. To mitigate both the reduction of bonding and the formation of cracks, the Illinois Department of Transportation proposed a new type of coated bars: textured epoxy-coated (TEC) bars. Over the last few years, different projects have been executed to understand and improve the characteristics of TEC rebars. This report is a continuation of research performed at the University of Illinois Urbana-Champaign to evaluate the bond behavior of TEC bars. The experimental program starts by characterizing, qualitatively and quantitatively, the roughness of the TEC rebars. Next, their bond-slip interaction embedded in concrete is evaluated through pull-out tests. Finite element models of these tests are developed to validate the behavior observed as the textured reinforcement loses anchorage with concrete. Based on these results, the experimental program then aims to study the impact of the drying shrinkage, temperature change, and flexural demands on two large-scale bridge deck specimens reinforced, individually, with TEC and standard epoxy-coated bars. The results collected from both specimens using digital image correlation and strain gauges are compared to explore the differences exhibited by the traditional and the new type of reinforcement coatings in terms of stress distribution in bridge decks. Finally, given the specialized equipment and time-consuming procedure needed to calculate the roughness parameters of TEC bars, an empirical, weight-based approach is developed as a rapid method for assessing the rebars’ roughness on-site.
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Law, Edward, Samuel Gan-Mor, Hazel Wetzstein i Dan Eisikowitch. Electrostatic Processes Underlying Natural and Mechanized Transfer of Pollen. United States Department of Agriculture, maj 1998. http://dx.doi.org/10.32747/1998.7613035.bard.
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The project objective was to more fully understand how the motion of pollen grains may be controlled by electrostatic forces, and to develop a reliable mechanized pollination system based upon sound electrostatic and aerodynamic principles. Theoretical and experimental analyses and computer simulation methods which investigated electrostatic aspects of natural pollen transfer by insects found that: a) actively flying honeybees accumulate ~ 23 pC average charge (93 pC max.) which elevates their bodies to ~ 47 V likely by triboelectrification, inducing ~ 10 fC of opposite charge onto nearby pollen grains, and overcoming their typically 0.3-3.9 nN detachment force resulting in non-contact electrostatic pollen transfer across a 5 mm or greater air gap from anther-to-bee, thus providing a theoretical basis for earlier experimental observations and "buzz pollination" events; b) charge-relaxation characteristics measured for flower structural components (viz., 3 ns and 25 ns time constants, respectively, for the stigma-style vs. waxy petal surfaces) ensure them to be electrically appropriate targets for electrodeposition of charged pollen grains but not differing sufficiently to facilitate electrodynamic focusing onto the stigma; c) conventional electrostatic focusing beneficially concentrates pollen-deposition electric fields onto the pistill tip by 3-fold as compared to that onto underlying flower structures; and d) pollen viability is adequately maintained following exposure to particulate charging/management fields exceeding 2 MV/m. Laboratory- and field-scale processes/prototype machines for electrostatic application of pollen were successfully developed to dispense pollen in both a dry-powder phase and in a liquid-carried phase utilizing corona, triboelectric, and induction particulate-charging methods; pollen-charge levels attained (~ 1-10 mC/kg) provide pollen-deposition forces 10-, 77-, and 100-fold greater than gravity, respectively, for such charged pollen grains subjected to a 1 kV/cm electric field. Lab and field evaluations have documented charged vs. ukncharged pollen deposition to be significantly (a = 0.01-0.05) increased by 3.9-5.6 times. Orchard trials showed initial fruit set on branches individually treated with electrostatically applied pollen to typically increase up to ~ 2-fold vs. uncharged pollen applications; however, whole-tree applications have not significantly shown similar levels of benefit and corrective measures continue. Project results thus contribute important basic knowledge and applied electrostatics technology which will provide agriculture with alternative/supplemental mechanized pollination systems as tranditional pollen-transfer vectors are further endangered by natural and man-fade factors.