Academic literature on the topic 'Sprung mass'

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Journal articles on the topic "Sprung mass"

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Pence, Benjamin, Joseph Hays, Hosam K. Fathy, Corina Sandu, and Jeffrey Stein. "Vehicle sprung mass estimation for rough terrain." International Journal of Vehicle Design 61, no. 1/2/3/4 (2013): 3. http://dx.doi.org/10.1504/ijvd.2013.050837.

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Chahyadi, Hendry D. "Simulation and Analysis of Two-Mass Suspension Modification Using MATLAB Programming." ACMIT Proceedings 3, no. 1 (March 18, 2019): 160–65. http://dx.doi.org/10.33555/acmit.v3i1.39.

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The designs of automotive suspension system are aiming to avoid vibration generated by road condition interference to the driver. This final project is about a quarter car modeling with simulation modeling and analysis of Two-Mass modeling. Both existing and new modeling are being compared with additional spring in the sprung mass system. MATLAB program is developed to analyze using a state space model. The program developed here can be used for analyzing models of cars and vehicles with 2DOF. The quarter car modelling is basically a mass spring damping system with the car serving as the mass, the suspension coil as the spring, and the shock absorber as the damper. The existing modeling is well-known model for simulating vehicle suspension performance. The spring performs the role of supporting the static weight of the vehicle while the damper helps in dissipating the vibrational energy and limiting the input from the road that is transmitted to the vehicle. The performance of modified modelling by adding extra spring in the sprung mass system provides more comfort to the driver. Later on this project there will be comparison graphic which the output is resulting on the higher level of damping system efficiency that leads to the riding quality.
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Liu, Zheng, Yuzhuang Zhao, and Sizhong Chen. "A Dual-Observer Design for Nonlinear Suspension System Based on Feedback Linearization." Mathematical Problems in Engineering 2018 (December 26, 2018): 1–13. http://dx.doi.org/10.1155/2018/2485263.

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A novel approach to estimate suspension state information and payload condition was developed in this article. A nonlinear quarter car model with air spring and damper was built. After verification of system observability and solvability, a certain coordinate transform was built to transform the nonlinear system into a linear one. Then a Kalman filter observer was applied. A sprung mass observer, which works cooperatively with suspension state information observer, was also designed. Designed dual-observer was verified under typical road profile and sprung mass disturbance. Compared with extended Kalman filter, the dual-observer showed better accuracy and robustness.
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Zhou, Ding, and Tianjian Ji. "Free Vibration of Rectangular Plates with Attached Discrete Sprung Masses." Shock and Vibration 19, no. 1 (2012): 101–18. http://dx.doi.org/10.1155/2012/983576.

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A direct approach is used to derive the exact solution for the free vibration of thin rectangular plates with discrete sprung masses attached. The plate is simply supported along two opposite edges and elastically supported along the two other edges. The elastic support can represent a range of boundary conditions from free to clamped supports. Considering only the compatibility of the internal forces between the plate and the sprung masses, the equations of the coupled vibration of the plate-spring-mass system are derived. The exact expressions for mode and frequency equations of the coupled vibration of the plate and sprung masses are determined. The solutions converge steadily and monotonically to exact values. The correctness and accuracy of the solutions are demonstrated through comparison with published results. A parametric study is undertaken focusing on the plate with one or two sprung masses. The results can be used as a benchmark for further investigation.The solution provided in the paper is general and includes several special cases, such as the plate with classical boundary conditions, the plate attached with discrete rigid masses, the plate supported by discrete springs and the plate restricted by rigid vertical point-supports.
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Yao, Jun, Jinqiu Zhang, Mingmei Zhao, and Hu Peng. "Analysis of Dynamic Stability of Nonlinear Suspension concerning Slowly Varying Sprung Mass." Shock and Vibration 2017 (2017): 1–12. http://dx.doi.org/10.1155/2017/5341929.

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In this paper, the stability of vehicle concerning the slow-varying sprung mass is analyzed based on two degrees of freedom quarter-car model. A mathematical model of vehicle is established, the nonlinear vibration caused by sprung mass vibration is solved, and frequency curve is obtained. The characteristics of a stable solution and the parameters affecting the stability are analyzed. The numeric solution shows that a slow-varying sprung mass is equivalent to adding a negative damping coefficient to the suspension system, making the effective damping coefficient change from negative to positive. Such changing parameters lead to Hopf bifurcation and a shrinking limit cycle. The simulation results indicate the existence of static as well as dynamic bifurcation and the result is a change in the final stable vibration of the suspension. Even the tiny vibration of the sprung mass will lead to amplitude mutation, leading to the sprung mass instability.
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Papagiannakis, A. T., and B. Raveendran. "International Standards Organization-Compatible Index for Pavement Roughness." Transportation Research Record: Journal of the Transportation Research Board 1643, no. 1 (January 1998): 110–15. http://dx.doi.org/10.3141/1643-14.

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The development of a new pavement roughness index, which is compatible to the current International Standards Organization (ISO) standard on “exposure to whole-body vibration” is described. The index was intended to be the independent variable in the future development of relationships between user cost (i.e., vehicle depreciation, repairs, discomfort and so on) and pavement roughness; hence it was named RIDE (Roughness Index for Driving Expenditure). RIDE is based on the sprung mass acceleration response of a reference vehicle to the pavement profile. It is calculated in the frequency domain by multiplying the power spectral density (PSD) of the pavement profile by the square of the transfer function of the sprung mass acceleration of the reference vehicle. The resulting sprung mass acceleration PSD is integrated over frequency to yield the root-mean-square of the sprung mass acceleration per unit length of pavement traveled. The sprung mass acceleration is shown to be the main contributor of dynamic axle loads in heavy trucks, which relate to vehicle and cargo damage and also to pavement damage.
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Zhao, Wanzhong, Lin Ji, and Chunyan Wang. "H∞ control of integrated rollover prevention system based on improved lateral load transfer rate." Transactions of the Institute of Measurement and Control 41, no. 3 (June 6, 2018): 859–74. http://dx.doi.org/10.1177/0142331218773527.

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A rollover dynamic model that merges the active front steering model and differential braking model is established in this paper. After analyzing and improving the existing rollover evaluation method, a new evaluation method that takes both sprung mass and under-sprung mass into consideration is proposed. The reliability of the improved LTR (lateral load transfer rate) is confirmed by simulation results obtained from MATLAB and CARSIM where, all of three evaluation methods are taken under the same condition. The accuracy of the rollover evaluation index depends on the centroid height of under-sprung mass and the ratio of under-sprung mass and under-sprung mass. In order to achieve the desired tracking effect and anti-jamming capability, an integrated rollover control system based on active steering and differential braking is designed where a H∞ controller is adopted. The results of simulation under J-turn condition indicate that the control system has strong stability and robustness. When the vehicle is under the risk of rollover and reaches the setting threshold, the designed H∞ controller will actively keep the vehicle under the critical state.
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Jeniš, Filip, and Ivan Mazůrek. "Sprung mass positioning by semi-actively controlled damper." MATEC Web of Conferences 322 (2020): 01051. http://dx.doi.org/10.1051/matecconf/202032201051.

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Recently, the intensive wear of rails, especially in curves of small radii and at switches, has been studied. The wear is caused by the high lateral force peak of the wheel against the rail when entering the curves. An effective solution for reducing undesirable lateral forces on the rail is to rotate the vehicle bogie in the direction of the rail curve, which influences the distribution of lateral force over the first and second wheelset. This reduces the force peak and thus the track wear. The bogie rotation is nowadays realized by actuators, which replace the yaw dampers. However, actuator implementation is complicated, expensive, energyintensive and demanding for the performance of a fail-safe system. From this point of view, a semi-actively controlled yaw damper appears to be a better candidate. An algorithm such as Skyhook can hold the sprung mass in the desired position. It is believed to be possible to rotate the vehicle bogie by the special S/A control strategy of a yaw damper. This paper deals with the possibilities and limits of the positioning of the sprung mass by the semi-actively controlled damper. It has been shown that the system relative attenuation and the damper response time have the greatest influence on the mass positioning efficiency.
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Zhu, Xing Xing, and Si Hong Zhu. "A Theoretical Model for Calculating Vibration Characteristics of A Kind of Driver Seat with Air Spring and MR Damper." Applied Mechanics and Materials 141 (November 2011): 8–14. http://dx.doi.org/10.4028/www.scientific.net/amm.141.8.

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In order to further reduce the vibration transmitted from vehicle to driver, a new model of driver scissors linkage seat suspension was put forward, in which an air spring with auxiliary chamber and a MR damper are between the face and floor of the seat. The motion differential equation of this seat suspension system was established and the theoretical computing formulation of it’s equivalent vertical stiffness, equivalent damping coefficient, natural frequency and damping rate were deduced. Besides, taking HY-Z04 scissors linkage seat, SK37-6 air spring of ContiTech and RD-1005-3 MR damper of LORD as an example, the equivalent stiffness and damping coefficient in different conditions of the air spring pressure, the sprung mass, the orifice diameter and MR damping were computed and analyzed. The study results show that the air spring pressure, the sprung mass, the orifice diameter and MR damping all have obvious influence on the equivalent stiffness and damping coefficient, so the seat comfort can be improved by changing the air spring pressure, the orifice diameter and MR damping according to driver’s weight and road condition.
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Nagarkar, Mahesh, and G. J. Vikhe Patil. "Optimization of the linear quadratic regulator (LQR) control quarter car suspension system using genetic algorithm." Ingeniería e Investigación 36, no. 1 (April 18, 2016): 23–30. http://dx.doi.org/10.15446/ing.investig.v36n1.49253.

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<p>In this paper, a genetic algorithm (GA) based in an optimization approach is presented in order to search the optimum weighting matrix parameters of a linear quadratic regulator (LQR). A Macpherson strut quarter car suspension system is implemented for ride control application. Initially, the GA is implemented with the objective of minimizing root mean square (RMS) controller force. For single objective optimization, RMS controller force is reduced by 20.42% with slight increase in RMS sprung mass acceleration. Trade-off is observed between controller force and sprung mass acceleration. Further, an analysis is extended to multi-objective optimization with objectives such as minimization of RMS controller force and RMS sprung mass acceleration and minimization of RMS controller force, RMS sprung mass acceleration and suspension space deflection. For multi-objective optimization, Pareto-front gives flexibility in order to choose the optimum solution as per designer’s need.</p>
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Dissertations / Theses on the topic "Sprung mass"

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Shimp, Samuel Kline III. "Vehicle Sprung Mass Parameter Estimation Using an Adaptive Polynomial-Chaos Method." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/32056.

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The polynomial-chaos expansion (PCE) approach to modeling provides an estimate of the probabilistic response of a dynamic system with uncertainty in the system parameters. A novel adaptive parameter estimation method exploiting the polynomial-chaos representation of a general quarter-car model is presented. Because the uncertainty was assumed to be concentrated in the sprung mass parameter, a novel pseudo mass matrix was developed for generating the state-space PCE model. In order to implement the PCE model in a real-time adaptation routine, a novel technique for representing PCE output equations was also developed. A simple parameter estimation law based on the output error between measured accelerations and PCE acceleration estimates was developed and evaluated through simulation and experiment. Simulation results of the novel adaptation algorithm demonstrate the estimation convergence properties as well as its limitations. The simulation results are further verified by a real-time experimental implementation on a quarter-car test rig. This work presents the first truly real-time implementation of a PCE model. The experimental real-time implementation of the novel adaptive PCE estimation method shows promising results by its ability to converge and maintain a stable estimate of the unknown parameter.
Master of Science
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Jaroš, Petr. "Konstrukce 1/4 modelu vozidla pro testy tlumičů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-442802.

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This thesis deals by the design of 1/4 car model for testing vehicle dampers, which can be used to simulate the real suspension of a vehicle wheel (up to a maximum car weight of 1,970 kg) and the so-called linear wheel suspension. A linear mathematical 1/4 car model with 2 DOF (Degrees Of Freedom) and data from literature search are used to design and derive the basic parameters of the device. The thesis contains a description of the linear mathematical model and its outputs (acceleration of the sprung mass and forces acting on the sprung mass), description of designed device, descriptions of created simulations (static, modal and harmonic analysis in ANSYS Workbench 2020 R2) and conceptual design of the modifications this device for another possible use for testing of bicycles.
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Harwood, Michael J. "Mass-spring modelling of vault springboard contact." Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/7078.

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Vaulting is a discipline in Men's and Women's Artistic Gymnastics. While the springboard contact is not judged, the success of the rest of the vault is underpinned by it. The purpose of this study was to develop an understanding of the mechanics of the springboard contact phase of gymnastic vaulting. An analysis of hopping in place, forward hopping and running jumps on a force platform showed that the force-mass centre displacement relationship during ground contact approximated that of a mass rebounding on a linear spring. Subsequently, two mass-spring models were developed using a symbolic mathematics package. Both models represented the gymnast as a rigid cylinder, with personalized linear and angular inertia characteristics, connected at its mass centre to a linear spring. A one spring model combined the springiness of the gymnast and the springboard in a single linear spring, while a two spring model treated them as separate linear springs. Handspring vaults performed by an elite male gymnast at a range of approach speeds and springboard settings were analysed to provide model inputs. Springboard properties were empirically determined and revealed that the springboard stiffness varied appreciably depending upon feet contact position. Given the touchdown kinematics and takeoff angle of the gymnast, the models estimated spring stiffness and linear and angular takeoff velocities, the spring stiffness and takeoff vertical velocity estimates showing some sensitivity to spring angle at touchdown. Simulations in which the touchdown kinematics and spring stiffnesses were systematically adjusted, identified their influence on takeoff kinematics and provided an insight into the mechanics of springboard. contact. Estimated (leg) spring stiffnesses were consistent with those reported in the literature for other activities and'simulation results showed that simple rebounds accounted for the majority of the takeoff velocities. Spring angle at touchdown was found to be most effective at modifying each of the takeoff variables, however to produce a selective effect on takeoff required a combination of adjustments to the touchdown. In proposing strategies for gymnasts, their ability to control each of the touchdown variables has to be considered.
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Taminato, Rodrigo Luis. "Estudo quimico do Allium tuberosum Rottl. ex Spreng biomonitorado pela avaliação da atividade anti-Candida albicans." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290221.

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Orientadores: Vera Lucia Garcia Rehder, Marta Cristina Teixeira Duarte
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-06T20:58:10Z (GMT). No. of bitstreams: 1 Taminato_RodrigoLuis_M.pdf: 889161 bytes, checksum: 74c08f7f56d17f89884a6856839f1ba1 (MD5) Previous issue date: 2006
Resumo: De uso freqüente na medicina popular, o gênero Allium inclui mais de 600 espécies encontradas em diversas regiões do mundo como Europa, América do Norte, África e Ásia. A maioria das espécies é comestível e possui aroma e odor característicos, sendo também utilizadas como hipocolesterolêmico, antigripal e antimicrobiano. Alguns estudos de determinação das propriedades de Allium spp. como antifúngico e de identificação de seus compostos voláteis foram conduzidos. A maior parte de seus constituintes são compostos sulfurados, embora a composição química seja variável entre os diferentes estudos. Dentre as espécies de Allium spp., o A. tuberosum Rottl. ex Spreng (Liliaceae) pertence a mesma família do alho, cebola e alho-poró, é conhecido também como "Chinese chive", sendo um importante ingrediente na culinária asiática, também utilizado como erva medicinal para muitas disfunções e doenças. Na China é popularmente chamado de "Jiucai" e no Japão de "Nirá". Os óleos essenciais das folhas e bulbos deA. tuberosum obtidos por hidrodestilação em sistema do tipo Clevenger. As fases aquosas ou hidrolatos foram extraídas com diclorometano, obtendo-se o OB (óleo essencial dos bulbos) - 810 mg (0,12%) e o OF (óleo essencial das folhas) -750 mg (0,15%). O extrato dic1orometânico obtido dos bulbos - EB, obtido em sistema Ultra-Turrax, apresentou rendimento 3,28% (497 mg).O OB foi fracionado em coluna seca, utilizando como eluente dic1orometano. Foram obtidas, 8 frações (FI a F8), analisadas por CCD. As frações 3, 4 e 5 foram agrupadas resultando nas frações: FI - 138,6mg (33%), F2 - 15,3mg (3,7%), F3 - 13,6mg (3,3 %), F4 - 51,9 (12,6%), F5 - 34,lmg (8,3%), F6 - 31,2mg (7,6%). Analisados por CG-MS observa-se que a maioria dos compostos identificados nos óleos essenciais das folhas e bulbos e das frações obtidas do OB são compostos organosulfetos (COS). As principais classes de sulfetos identificadas nas diferentes amostras de A. tuberosum, destacam-se os monosulfetos, disulfetos, trisulfetos, tetrassulfetos e sulfinatos. Na avaliação do MIC obtiveram-se atividade do OB de 200ug/mL e das frações mais ativas FI (50ug/mL) e F2 (50ug/mL). Concluii-se que os principais compostos responsáveis pela atividade anti Candida albicans do Allium tuberosum são alil,metil-disulfeto, dimetil-trisulfeto, dialildisulfeto e alil,metil-trisulfeto, presentes no óleo essencial dos bulbos e nas frações FI e F2
Abstract: Frequently used in folk medicine, the genus Allium include more than 600 species founded in several world regions like Europe, North America, Africa and Asia. The most of species is edible and have a aroma and smell characteristics, being algo used as hypocholesterolemic, anticold and antimicrobial. Among theAllium species,A. tuberosum Rottl. ex Spreng (Liliaceae) belongs to the same family of the garlic, anion and poroallium. In the China, is popularly called "Jiucai" and in Japan, "Nirá" and is also know as "Chinese chive", a important ingredient in the Asiatic culinary. Studies aims determine the properties of Allium spp. as antifungical and aim identify their volatile compounds are described in literature. The essential oils from leaves (OF) and bulbs (OB) ofA. tuberosum were obtained by hydrodistillation in a Clevenger system, yielding 0,15% and 0,12%, respectively. The dichloromethanic extract from bulbs (EB), obtained in a Ultra-Turrax system, presented yield of 3,28%. The minimal inhibitory concentration (MIC) from oils against Candida albicans was: OF (>1000ug/mL), OB (200ug/mL) and EB (250ug/mL). The OB was fractionated in dry column by use of dichloromethane as eluent, when were obtairied six fractions: FI (33%), F2 (3,7%), F3 (3,3 %), F4 (12,6%), F5 (8,3%), F6 (7,6%), evaluated to anti-C. albicans activity. The volatile compounds present in the essential oils, extract and fractions of OB were identified by CG-MS. The major,ity compounds present in the OF, OB and in the FI and F2 from OB were organosulphides from disulphides classes, trisulphides, tetrasulphides and sulphinides, to standing out the allyl, methyl-disulphide, dimethyl-trisulphide, diallyl-disulphide and alil, methyl trisulphide. Significant quantities of limonene and sulphinades and low concentration of other sulphides were founded in EB. The MIC evaluation of fractions obtained from OB revealed a significant increase of activity for FI and F2, with MIC value of 50ug/mL, when compared to OB (200ug/mL). These results indicate that the main compounds from A. tuberosum responsible by anti-Candida activity are allyl, methyl-disulphide, dimethyltrisulphide, diallyl-disulphide and diallyl disulphide, present in higher concentration in OB and in the fractions FI e F2
Mestrado
Farmacologia, Anestesiologia e Terapeutica
Mestre em Odontologia
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Langenfeld, Jonathan Wayne. "Wave Propagation and Vibration of Spring-Mass Systems." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/298.

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AN ABSTRACT OF THE THESIS OF JONATHAN WAYNE LANGENFELD, for the Master of Science degree in Mechanical Engineering and Energy Processes, presented on 28 October 2010, at Southern Illinois University Carbondale. TITLE: WAVE PROPAGATION AND VIBRATION OF SPRING-MASS SYSTEMS MAJOR PROFESSOR: Dr. Serge Abrate The main focus of this research was to study wave propagation and modeling techniques of spring-mass systems. The purpose is to show that by engineering a materials microstructure, the material can have wave filtering capabilities. Numerical solutions were obtained for the steady-state response of a uniform, alternating, and branched spring-mass chain. The spring-mass chains studied were excited by harmonic forces; it is shown how gaps exist in the frequency ranges which can be applied to the chain, to filter wave propagation. The spring-mass chains were modeled as a continuum being governed by the wave equation or higher order models such as Love's rod theory. It was concluded that the best agreement was found between the spring-mass chain and the continuum models when excited by very low frequencies. Transient response problems are addressed for uniform materials, sandwiched materials, laminates, and graded materials. Analytical solutions for the response to these problems are presented along with numerical solutions using the finite element method. Step and impulse loading cases are studied to monitor if and how the initial wave pulse distorts upon propagation through a material. Underwater blast loading cases are studied which model water as a uniform bar transmitting waves into the hull of a sea going vessel. Results are presented for one-dimensional cloaking scenarios. Cloaking models are created from basic two component models and increased to four component models. Analytical and numerical solutions are obtained proving that the magnitude of reflected waves can be reduced by gradually decreasing the wave speed with each added layer. All of the results obtained throughout this research agree that the microstructure of a material can be engineered to control wave propagation.
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Golec, Karolina. "Hybrid 3D Mass Spring System for Soft Tissue Simulation." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1004/document.

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La nécessité de simulations de tissus mous, tels que les organes internes, se pose avec le progrès des domaines scientifiques et médicaux. Le but de ma thèse est de développer un nouveau modèle générique, topologique et physique, pour simuler les organes humains. Un tel modèle doit être facile à utiliser, doit pouvoir effectuer des simulations en temps réel avec un niveau de précision permettant l'utilisation à des fins médicales. Cette thèse explore de nouvelles méthodes de simulation et propose des améliorations pour la modélisation de corps déformables. Les méthodes proposées visent à pouvoir effectuer des simulations rapides, robustes et fournissant des résultats physiquement précis. L'intérêt principal de nos solutions réside dans la simulation de tissus mous élastiques a petites et grandes déformations à des fins médicales. Nous montrons que pour les méthodes existantes, la précision pour simuler librement des corps déformables ne va pas de pair avec la performance en temps de calcul. De plus, pour atteindre l'objectif de simulation rapide, de nombreuses approches déplacent certains calculs dans une étape de pré-traitement, ce qui entraîne l'impossibilité d'effectuer des opérations de modification topologiques au cours de la simulation comme la découpe ou le raffinement. Dans cette thèse, le cadre utilisé pour les simulations s'appelle TopoSim. Il est conçu pour simuler des matériaux à l'aide de systèmes masses-ressorts (MSS) avec des paramètres d'entrée spécifiques. En utilisant un MSS, qui est connu pour sa simplicité et sa capacité à effectuer des simulations temps réel, nous présentons plusieurs améliorations basé physiques pour contrôler les fonctionnalités globales du MSS qui jouent un rôle clé dans la simulation de tissus réels. La première partie de ce travail de thèse vise à reproduire une expérience réelle de simulation physique qui a étudié le comportement du tissu porcin à l'aide d'un rhéomètre rotatif. Son objectif était de modéliser un corps viscoélastique non linéaire. A partir de l'ensemble des données acquises, les auteurs de l'expérience ont dérivé une loi de comportement visco-élastique qui a ensuite été utilisée afin de la comparer avec nos résultats de simulation. Nous définissons une formulation des forces viscoélastiques non linéaires inspirée de la loi de comportement physique. La force elle-même introduit une non linéarité dans le système car elle dépend fortement de l'amplitude de l'allongement du ressort et de trois paramètres spécifiques à chaque type de tissu. La seconde partie de la thèse présente notre travail sur les forces de correction de volume permettant de modéliser correctement les changements volumétriques dans un MSS. Ces forces assurent un comportement isotrope des solides élastiques et un comportement correct du volume quel que soit la valeur du coefficient de Poisson utilisé. La méthode nécessite de résoudre deux problèmes: l'instabilité provoquant des plis et les contraintes de Cauchy. Nos solutions à ces limitations impliquent deux étapes. La première consiste à utiliser trois types de ressorts dans un maillage entièrement hexaédrique: les arêtes, les faces diagonales et les diagonales internes. Les raideurs des ressorts dans le système ont été formulées pour obéir aux lois mécaniques de base. La deuxième étape consiste à ajouter des forces de correction linéaires calculées en fonction du changement de volume et des paramètres mécaniques du tissu simulé, à savoir le coefficient de Poisson et le module de Young [etc…]
The need for simulations of soft tissues, like internal organs, arises with the progress of the scientific and medical environments. The goal of my PhD is to develop a novel generic topological and physical model to simulate human organs. Such a model shall be easy to use, perform the simulations in the real time and which accuracy will allow usage for the medical purposes.This thesis explores novel simulation methods and improvement approaches for modeling deformable bodies. The methods aim at fast and robust simulations with physically accurate results. The main interest lies in simulating elastic soft tissues at small and large strains for medical purposes. We show however, that in the existing methods the accuracyto freely simulate deformable bodies and the real-time performance do not go hand in hand. Additionally, to reach the goal of simulating fast, many of the approaches move the necessary calculations to pre-computational part of the simulation, which results in inability to perform topological operations like cutting or refining.The framework used for simulations in this thesis is designed to simulate materials using Mass Spring Systems (MSS) with particular input parameters. Using Mass-Spring System, which is known for its simplicity and ability to perform fast simulations, we present several physically-based improvements to control global features of MSS which play the key role in simulation of real bodies
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Eriksson, Emil. "Simulation of Biological Tissue using Mass-Spring-Damper Models." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-27663.

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The goal of this project was to evaluate the viability of a mass-spring-damper based model for modeling of biological tissue. A method for automatically generating such a model from data taken from 3D medical imaging equipment including both the generation of point masses and an algorithm for generating the spring-damper links between these points is presented. Furthermore, an implementation of a simulation of this model running in real-time by utilizing the parallel computational power of modern GPU hardware through OpenCL is described. This implementation uses the fourth order Runge-Kutta method to improve stability over similar implementations. The difficulty of maintaining stability while still providing rigidness to the simulated tissue is thoroughly discussed. Several observations on the influence of the structure of the model on the consistency of the simulated tissue are also presented. This implementation also includes two manipulation tools, a move tool and a cut tool for interaction with the simulation. From the results, it is clear that the mass-springdamper model is a viable model that is possible to simulate in real-time on modern but commoditized hardware. With further development, this can be of great benefit to areas such as medical visualization and surgical simulation.
Målet med detta projekt var att utvärdera huruvida en modell baserad på massa-fjäderdämpare är meningsfull för att modellera biologisk vävnad. En metod för att automatiskt generera en sådan modell utifrån data tagen från medicinsk 3D-skanningsutrustning presenteras. Denna metod inkluderar både generering av punktmassor samt en algoritm för generering av länkar mellan dessa. Vidare beskrivs en implementation av en simulering av denna modell som körs i realtid genom att utnyttja den parallella beräkningskraften hos modern GPU-hårdvara via OpenCL. Denna implementation använder sig av fjärde ordningens Runge-Kutta-metod för förbättrad stabilitet jämfört med liknande implementationer. Svårigheten att bibehålla stabiliteten samtidigt som den simulerade vävnaden ges tillräcklig styvhet diskuteras genomgående. Flera observationer om modellstrukturens inverkan på den simulerade vävnadens konsistens presenteras också. Denna implementation inkluderar två manipuleringsverktyg, ett flytta-verktyg och ett skärverktyg för att interagera med simuleringen. Resultaten visar tydligt att en modell baserad på massa-fjäder-dämpare är en rimlig modell som är möjlig att simulera i realtid på modern men lättillgänglig hårdvara. Med vidareutveckling kan detta bli betydelsefullt för områden så som medicinsk bildvetenskap och kirurgisk simulering.
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Hrudík, Jan. "Přední náprava vysokovýkonného sportovního vozu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-443475.

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Tato diplomová práce byla psána při studentské zahraniční stáži, pod záštitou Evropské Unie – program „ERASMUS Student Mobility for Placement“. Stáž byla absolvována mezi prosincem 2010 a květnem 2011 ve společnosti a.d.Tramontana, mající sídlo v Palau de Santa Eulália, Španělsko. Pro kompletní návrh podvozku a odpružení jakéhokoli vozidla je nezbytná znalost mnoha technických disciplín. Tato diplomová práce se zabývá dvěma z nich – odpružení a řízení. Nejprve je rozebrána teorie, na kterou se může navázat v praktické části práce. Velká pozornost byla věnována srozumitelnosti textu a názornosti obrázků, bez zbytečných detailů, avšak bez vynechání důležitého. Tuto práci je tedy možné užít jako prvního kroku před návrhem podvozku. V další části je popsáno, jak byla probraná teorie využita při návrhu řízení u skutečného vozu, přičemž největší pozornost je věnována Ackermannově teorii řízení a geometrii zabraňující samořízení při propružení. V závěrečných částech je pozornost věnována ukázce některých z každodenních činností v malosériové výrobě automobilů – jde o zjištění maximálně možného pohybu kola při propružení a proces výroby příčných trojúhelníkových ramen včetně návrhu jejich připevnění k šasi.
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Ojima, Hirotaka, Kenji Nagase, and Yoshikazu Hayakawa. "Wave-based analysis and wave control of damped mass-spring systems." IEEE, 2001. http://hdl.handle.net/2237/6856.

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Holt-Phoenix, Marianne S. (Marianne Shue). "Wave propagation in finite element and mass-spring-dashpot lattice models." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35683.

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Thesis (Nav. E. and S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.
Includes bibliographical references (p. 42).
Numerical efficiency comparisons of a four-node finite element model (FEM), a mass-spring lattice model (MSLM), and a mass-spring-dashpot lattice model (MSDLM) are investigated. Specifically, the error in the ultrasonic phase speed with variations in Poisson's ratio and angle of incidence is evaluated in each model of an isotropic elastic solid. With regard to phase speed, materials with constant N grid spaces per P-wavelength having Poisson's ratios between 0.0 and 0.25 are modeled more accurately with the MSLM. Materials with Poisson's ratios between 0.35 and 0.5 and N grid spaces per P-wavelength are more accurately modeled with the FEM. Materials whose Poisson's ratio is between 0.25 and 0.35 are modeled equally accurately. With regard to phase speed, viscoelastic materials modeled with FEM and MSDLM show good agreement with known analytical solutions. The computational expense of all three models is also examined. The number of floating point operations (FLOPS) needed to achieve a specified phase speed accuracy is calculated for each different model. While the FEM and MSLM have nearly the same computation cost, the MSDLM is 5 times more costly than either the FEM or MSLM.
by Marianne S. Holt-Phoenix.
Nav.E.and S.M.
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Books on the topic "Sprung mass"

1

Heon, Laura Steward. Unnatural science: An exhibition, Spring 2000 - Spring 2001, MASS MoCA. North Adams, Mass: MASS MoCA Publications, 2000.

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Heon, Laura Steward. Unnatural science: An exhibition - Spring 2000-Spring 2001, MASS MoCA. North Adams, Mass: MASS MoCA Publications, 2000.

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Eav, Bov Bang. Performance evaluation of the spruce budworm egg mass counter: Prototype II. Fort Collins, Colo: U.S. Dept. of Agriculture, Forest Service, Forest Pest Management, Methods Applications Group, 1986.

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United States Geological Survey. Ground-water levels spring 1985, and ground-water level changes spring 1983 to spring 1985, in three basalt units underlying the Columbia Plateau, Washington and Oregon. [Tacoma, Wash.]: The Survey, 1989.

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Geopolitics of deception: Media, framing, and war by other means. Abu Dhabi, United Arab Emirates: The Emirates Center for Strategic Studies and Research, 2014.

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United States Geological Survey. Bedrock geologic map of the Spring Hill quadrangle, Connecticut. Reston, VA: U.S. Geological Survey, 1988.

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Pennypacker, Sara. Clementine and the spring trip. New York: Disney Hyperion Books, 2013.

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al-Iʻlām wa-al-thawarāt al-ʻArabīyah. al-Qāhirah: Muʼassasat Ṭībah lil-Nashr wa-al-Tawzīʻ, 2013.

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United States Geological Survey. Geologic map of the Pahroc Spring NE quadrangle, Lincoln County, Nevada. Reston, VA: U.S. Geological Survey, 1994.

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Billingsley, George H. Geologic map of the Russell Spring quadrangle, northern Mohave County, Arizona. [Menlo Park, CA]: U.S. Dept. of the Interior, U.S. Geological Survey, 1993.

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Book chapters on the topic "Sprung mass"

1

Lynch, Gordon S., David G. Harrison, Hanjoong Jo, Charles Searles, Philippe Connes, Christopher E. Kline, C. Castagna, et al. "Spring-Mass Model." In Encyclopedia of Exercise Medicine in Health and Disease, 809. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-540-29807-6_3063.

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Magrab, Edward B. "Spring-Mass Systems." In Solid Mechanics and Its Applications, 7–82. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-2672-7_2.

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Khaled, Nassim. "Mass-Spring-Damper Oscillations." In Virtual Reality and Animation for MATLAB® and Simulink® Users, 21–34. London: Springer London, 2011. http://dx.doi.org/10.1007/978-1-4471-2330-9_4.

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Eshkabilov, Sulaymon L. "Spring-Mass-Damper Systems." In Practical MATLAB Modeling with Simulink, 295–344. Berkeley, CA: Apress, 2020. http://dx.doi.org/10.1007/978-1-4842-5799-9_9.

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Ganguli, Ranjan. "Introduction: Spring-Mass Systems." In Isospectral Vibrating Systems, 1–32. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003155379-1.

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Becedas, Jonathan, Gabriela Mamani, Vicente Feliu, and Hebertt Sira-Ramírez. "Estimation of Mass-Spring-Dumper Systems." In Lecture Notes in Electrical Engineering, 411–22. Dordrecht: Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-1-4020-8919-0_28.

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Maykranz, Daniel, Sten Grimmer, Susanne Lipfert, and Andre Seyfarth. "Foot Function in Spring Mass Running." In Autonome Mobile Systeme 2009, 81–88. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-10284-4_11.

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Hutchinson, Dave, Martin Preston, and Terry Hewitt. "Adaptive Refinement for Mass/Spring Simulations." In Eurographics, 31–45. Vienna: Springer Vienna, 1996. http://dx.doi.org/10.1007/978-3-7091-7486-9_3.

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Bourguignon, David, and Marie-Paule Cani. "Controlling Anisotropy in Mass-Spring Systems." In Eurographics, 113–23. Vienna: Springer Vienna, 2000. http://dx.doi.org/10.1007/978-3-7091-6344-3_9.

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Duysak, Alpaslan. "Triangle Propagation for Mass-Spring Chain Algorithm." In Computer and Information Sciences – ISCIS 2006, 306–15. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/11902140_34.

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Conference papers on the topic "Sprung mass"

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Bixel, Ronald A., Gary J. Heydinger, Dennis A. Guenther, and S. Jay Novak. "Sprung/Unsprung Mass Properties Determination without Vehicle Diassembly." In International Congress & Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1996. http://dx.doi.org/10.4271/960183.

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Tang, Gang, Jinning Li, Chao Ding, and Yunqing Zhang. "Sprung Mass Identification of Suspension in a Simplified Model." In SAE 2014 World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2014. http://dx.doi.org/10.4271/2014-01-0051.

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Wang, Chunjian, Qian Wang, Jeffery Anderson, and Beshah Ayalew. "Sprung Mass Motion Emulation in a Braking Test Rig." In ASME 2015 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/detc2015-47691.

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This paper describes a quarter-car braking test rig that includes a hardware-in-the-loop (HIL) means for emulating broader vehicle dynamic effects. The test rig utilizes actual vehicle components such as the suspension-tire assembly and braking system to accurately represent a vehicle during a braking event and a chassis dynamometer’s drum is used to simulate the longitudinal vehicle dynamics. The key problem addressed in this paper is the emulation of sprung mass motion with a commercial electromagnetic linear actuator. By accurately representing the motion, detailed effects such as load transfer that happens in a real braking process can be studied for its effect on the braking performance. The stability of the system with sprung mass emulation under different actuator control modes is analyzed. The successful and stable control scheme found is a cascaded control with a velocity tracking strategy. The workings of the test are illustrated via representative test results that include a locked-wheel braking event and a stop with an anti-lock braking system (ABS).
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Huang, F., R. B. Gillespie, and A. Kuo. "Haptic feedback improves manual excitation of a sprung mass." In 12th International Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems, 2004. HAPTICS '04. Proceedings. IEEE, 2004. http://dx.doi.org/10.1109/haptic.2004.1287197.

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Song, Xubin. "Cost Effective Skyhook Control for Vibration Isolation Systems." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-82536.

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Traditionally a skyhook control, widely applied to vibration control, requires two sensors to measure sprung mass acceleration and relative displacement, respectively. For the implementation, these two measurement signals are converted into velocities and then the damping control signal is decided and sent to controllable HH/SS dampers. In this paper, a one sensor based skyhook control policy is developed. The proposed control policy just needs one measurement signal, sprung mass acceleration, to estimate these two velocities for semiactive control. The new strategy is explained through a typical spring-mass system of a quarter-car model. But the effectiveness of the new control approach for vibration isolation is validated with ride control through simulation study of a 7-DOF full car suspension system with application of magneto-rheological (MR) dampers.
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Pence, Benjamin L., Hosam K. Fathy, and Jeffrey L. Stein. "A Base-Excitation Approach to Polynomial Chaos-Based Estimation of Sprung Mass for Off-Road Vehicles." In ASME 2009 Dynamic Systems and Control Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/dscc2009-2641.

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This paper presents a novel method for identifying in real-time the sprung mass of a 2-DOF quarter-car suspension model. It does so by uniquely combining the base-excitation concept with polynomial chaos estimation. This unique combination of the two methods provides two important benefits. First, the base-excitation concept makes it possible to estimate the sprung mass without explicitly measuring or knowing the terrain profile prior to estimation. Second, the polynomial chaos estimation strategy makes it possible to perform such mass estimation using sprung and unsprung acceleration measurements without pseudo-integration filters that can be difficult to tune. This paper derives the proposed method in detail and presents computer simulations to evaluate its convergence speed and accuracy. The simulation results consistently converge to within 10% of the true mass value typically within 120 seconds.
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Aydan, Go¨ksu, Ender Cig˘erog˘lu, and S. C¸ag˘lar Bas¸lamıs¸lı. "Application of Tuned Mass Dampers and Lever Type Vibration Isolator to the Quarter-Car Model in Order to Increase Ride Comfort." In ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2010. http://dx.doi.org/10.1115/esda2010-24277.

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In this paper, performance of passive vibration isolators, namely rotational / linear tuned mass dampers (TMD) and lever type vibration isolators (LVI), are investigated under different configurations for optimal ride comfort. TMDs reduce vibration levels by absorbing the energy of the system, especially around natural frequencies with the help of viscous dampers. Two types of TMDs, rotational and linear, are investigated in this study. Although linear TMDs can be more easily implemented on suspension systems, rotational TMDs show better performance in reducing vibration levels. The reason is that, the inertia effect of rotational TMDs is higher than linear TMDs. In order to obtain better results with TMDs, a study on different possible configurations is conducted. A plate, with very small mass, is added between sprung and unsprung masses without changing the original suspension spring stiffness and damping coefficients and acts as a support for in-series TMD applications. Finally, LVIs are implemented to reduce sprung mass acceleration and more satisfactory results are obtained especially around body bounce frequency.
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Raghavan, Madhusudan. "Suspension Synthesis for N:1 Roll Center Motion." In ASME 2003 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/detc2003/dac-48810.

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A dimensional synthesis procedure to achieve prescribed roll center height variation of a vehicle’s sprung mass with respect to wheel jounce-rebound is presented. This may be used to size the relative lengths of the control arms of a short-long arm suspension mechanism in order to (i) fix the roll center with respect to ground, or (ii) fix the roll center relative to the sprung mass, or (iii) have the roll center move at a prescribed rate relative to the sprung mass, during wheel jounce-rebound. These design selections have a significant impact on the ride-handling characteristics of a vehicle. Numerical examples are provided to demonstrate the synthesis procedure.
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Rao, Nikhil, Zhuohua Shen, and Justin Seipel. "Comparing Legged Locomotion With a Sprung-Knee and Telescoping-Spring When Hip Torque is Applied." In ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/detc2013-13576.

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Legged locomotion has been a subject of study for many years. However, the role of the knee in whole-body dynamics of locomotion is not well understood, especially for non-conservative dynamics. Based upon a hip actuated Spring-Loaded Inverted Pendulum (Hip-actuated SLIP) model, we develop a more human-like, two-segment leg model with a pin-jointed springy knee, to see what effects a knee has in the context of an applied hip torque. Overall, we find that the governing equations for the two-segment (knee) version have a distinct structure when compared to the telescoping version of SLIP. The two-segment model with a knee spring influences forces acting on the mass center in a more complex way than a telescoping spring. While a wide variation of behavior is possible for the two-segment model, here we focus on comparing the dynamics for a special case when the knee spring resting angle is 90°. For this particular choice of resting knee angle we find that the knee version of actuated SLIP can have similar locomotion dynamics to the telescoping version of actuated SLIP. This result provides one explanation for how animals and robots with multi-segmented legs could produce overall center-of-mass dynamics that are similar to models with telescoping legs. Nonetheless, despite overall similarities for this special case, small differences in the stability of locomotion are still observed. In particular, we find that the knee version tends to be slightly more stable than the telescoping SLIP in terms of the allowable size of perturbations, while requiring higher input power.
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Sun Jianmin and Yang Qingmei. "Reducing PSD on acceleration of sprung mass by LMS adaptive control of active suspension." In 2008 Chinese Control Conference (CCC). IEEE, 2008. http://dx.doi.org/10.1109/chicc.2008.4605266.

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Reports on the topic "Sprung mass"

1

Corona, Edmundo. Dynamic elastic-plastic response of a 2-DOF mass-spring system. Office of Scientific and Technical Information (OSTI), February 2018. http://dx.doi.org/10.2172/1423527.

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Stewart, A. K., C. E. Heinrich, and T. D. Hubbard. Dendrogeomorphic evidence of frequent mass movement using reaction wood in black spruce: Alaska Highway milepost 1267, Northway Junction, Alaska. Alaska Division of Geological & Geophysical Surveys, August 2017. http://dx.doi.org/10.14509/29734.

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Williams, David W., and Richard A. Birdsey. Historical patterns of spruce budworm defoliation and bark beetle outbreaks in North American conifer forests: an atlas and description of digital maps. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northeastern Research Station, 2003. http://dx.doi.org/10.2737/ne-gtr-308.

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Evans, Julie, Kendra Sikes, and Jamie Ratchford. Vegetation classification at Lake Mead National Recreation Area, Mojave National Preserve, Castle Mountains National Monument, and Death Valley National Park: Final report (Revised with Cost Estimate). National Park Service, October 2020. http://dx.doi.org/10.36967/nrr-2279201.

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Vegetation inventory and mapping is a process to document the composition, distribution and abundance of vegetation types across the landscape. The National Park Service’s (NPS) Inventory and Monitoring (I&M) program has determined vegetation inventory and mapping to be an important resource for parks; it is one of 12 baseline inventories of natural resources to be completed for all 270 national parks within the NPS I&M program. The Mojave Desert Network Inventory & Monitoring (MOJN I&M) began its process of vegetation inventory in 2009 for four park units as follows: Lake Mead National Recreation Area (LAKE), Mojave National Preserve (MOJA), Castle Mountains National Monument (CAMO), and Death Valley National Park (DEVA). Mapping is a multi-step and multi-year process involving skills and interactions of several parties, including NPS, with a field ecology team, a classification team, and a mapping team. This process allows for compiling existing vegetation data, collecting new data to fill in gaps, and analyzing the data to develop a classification that then informs the mapping. The final products of this process include a vegetation classification, ecological descriptions and field keys of the vegetation types, and geospatial vegetation maps based on the classification. In this report, we present the narrative and results of the sampling and classification effort. In three other associated reports (Evens et al. 2020a, 2020b, 2020c) are the ecological descriptions and field keys. The resulting products of the vegetation mapping efforts are, or will be, presented in separate reports: mapping at LAKE was completed in 2016, mapping at MOJA and CAMO will be completed in 2020, and mapping at DEVA will occur in 2021. The California Native Plant Society (CNPS) and NatureServe, the classification team, have completed the vegetation classification for these four park units, with field keys and descriptions of the vegetation types developed at the alliance level per the U.S. National Vegetation Classification (USNVC). We have compiled approximately 9,000 existing and new vegetation data records into digital databases in Microsoft Access. The resulting classification and descriptions include approximately 105 alliances and landform types, and over 240 associations. CNPS also has assisted the mapping teams during map reconnaissance visits, follow-up on interpreting vegetation patterns, and general support for the geospatial vegetation maps being produced. A variety of alliances and associations occur in the four park units. Per park, the classification represents approximately 50 alliances at LAKE, 65 at MOJA and CAMO, and 85 at DEVA. Several riparian alliances or associations that are somewhat rare (ranked globally as G3) include shrublands of Pluchea sericea, meadow associations with Distichlis spicata and Juncus cooperi, and woodland associations of Salix laevigata and Prosopis pubescens along playas, streams, and springs. Other rare to somewhat rare types (G2 to G3) include shrubland stands with Eriogonum heermannii, Buddleja utahensis, Mortonia utahensis, and Salvia funerea on rocky calcareous slopes that occur sporadically in LAKE to MOJA and DEVA. Types that are globally rare (G1) include the associations of Swallenia alexandrae on sand dunes and Hecastocleis shockleyi on rocky calcareous slopes in DEVA. Two USNVC vegetation groups hold the highest number of alliances: 1) Warm Semi-Desert Shrub & Herb Dry Wash & Colluvial Slope Group (G541) has nine alliances, and 2) Mojave Mid-Elevation Mixed Desert Scrub Group (G296) has thirteen alliances. These two groups contribute significantly to the diversity of vegetation along alluvial washes and mid-elevation transition zones.
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Maps showing altitude of the potentiometric surface and changes in water level of the Sparta sand and Memphis sand aquifers in Eastern Arkansas, spring 1984. US Geological Survey, 1985. http://dx.doi.org/10.3133/wri854223.

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Maps showing altitude of the potentiometric surface and changes in water levels in the aquifer in the Sparta and Memphis Sands in eastern Arkansas, spring 1985. US Geological Survey, 1986. http://dx.doi.org/10.3133/wri864084.

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