Relevant bibliographies by topics / Torsional oscillations of the crank mechanism

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Torsional oscillations of the crank mechanism'

Author: Grafiati
Published: 4 June 2021
Last updated: 13 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Torsional oscillations of the crank mechanism.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Torsional oscillations of the crank mechanism"

1

Pasricha, M. S. Pasricha, and F. M. Hashim. "Effect of the reciprocating mass of slider-crank mechanism on torsional vibrations of diesel engine systems." ASEAN Journal on Science and Technology for Development 23, no. 1&2 (October 30, 2017): 71. http://dx.doi.org/10.29037/ajstd.94.

Full text
Abstract:
The torsional vibration phenomenon in the running gear of reciprocating engine systems isusually dealt with by considering a series of constant inertias connected by sections of massless shafting. However in reality, a slider crank mechanism is a vibrating system with varying inertia because the effective inertia of the total oscillating mass of each crank assembly varies twice per revolution of the crankshaft. Large variations in inertia torques can give rise to the phenomenonof secondary resonance in torsional vibration of modern marine diesel engines which can not be explained by conventional theory incorporating only the mean values of the varying inertias. In the past associated secondary resonances and regions of instability tended to be dismissed by most engineers as interesting but of no importance. The situation changed in recent years since there is evidence of the existence of thesecondary resonance effects which could have contributed to a number of otherwise inexplicable crankshaft failures in large slow speed marine engines. The cyclic variation of the polar moment of inertia of the reciprocating parts during each revolution causes a periodic variation of frequency and corres ponding amplitude of vibration of reciprocating engine systems. It also causes an increase in the speed range over which resonance effects are experienced and only a partial explanation of the behaviour of the systems has been worked out. It is impossible to avoid these instabilities by changes in thedesign , unless of course the variations in mass and spring constant can be made zero. In the present paper a critical appraisal of the regions of instability as determined from the equation of motion which takes into account variation of inertia is given. The motion in the form of complex waveforms is studied at different speeds of engine rotation. A comparison of theoretical results with Goldsbrough’s experimental resultsand Gregory’s analysis is included.
APA, Harvard, Vancouver, ISO, and other styles
2

Cheng, Shouguo, and Shulin Liu. "Dynamic Analysis of Slider-Crank Mechanism with a Cracked Rod." Mathematical Problems in Engineering 2018 (September 2, 2018): 1–7. http://dx.doi.org/10.1155/2018/8540546.

Full text
Abstract:
The dynamical equation of the slider-crank mechanism is established by using Lagrange equation and Newton’s second law. The slider-crank mechanism with an open crack rod is investigated and then establishes the equivalent mechanics model by a massless torsional spring to simulate the influence of the crack in the rod, and the mechanism of a cracked rod is divided into two subsystems. The dynamical equation of the slider-crank mechanism with a crack rod is established. Comparing the dynamic analysis results between with and without crack in the rod, the results show that the existence of the crack leads to a great change in the motion characteristics of the slider. The calculated maximum Lyapunov exponent is positive, which shows that the movement of the slider in the crank slider mechanism with a cracked rod is chaotic.
APA, Harvard, Vancouver, ISO, and other styles
3

Adiletta, G., and A. R. Guido. "Dynamical behaviour of a torsional system with parametric and external excitations." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 214, no. 7 (July 1, 2000): 955–73. http://dx.doi.org/10.1243/0954406001523182.

Full text
Abstract:
The dynamic behaviour of a torsional system with a one-cylinder, reciprocating compressor driven by an asynchronous motor is studied using a two degrees-of-freedom (2 DOF) lumped-parameter theoretical model. The model takes into account the variability of the mass moment of inertia of the crank mechanism and the presence of pressure forces loading the compressor piston. The influence of the ratio of the variable to the constant part of inertia in the crank mechanism and the effect of the load torque due to pressure forces acting on the piston are examined in relation to system dynamic behaviour. Experimental data, obtained with the adoption of a suitable rig, show that the theoretical indications can be considered reliable, despite the approximation that was given to the mathematical model as far as the treatment of the damping and the absence of clearances were concerned.
APA, Harvard, Vancouver, ISO, and other styles
4

Guzzomi, A. L., D. C. Hesterman, and B. J. Stone. "Variable inertia effects of an engine including piston friction and a crank or gudgeon pin offset." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 222, no. 3 (March 1, 2008): 397–414. http://dx.doi.org/10.1243/09544070jauto590.

Full text
Abstract:
In order to obtain greater accuracy in simulation, more sophisticated models are often required. When it comes to the torsional vibration of reciprocating mechanisms the effect of inertia variation is very important. It has been shown that the inclusion of this variation increases model accuracy for both single-cylinder and multi-cylinder engine torsional vibration predictions. Recent work by the present authors has revealed that piston-to-cylinder friction may modify an engine's ‘apparent’ inertia function. Kinematic analysis also shows that the piston side force and the dynamic piston-to-cylinder friction are interdependent. This has implications for engine vibration modelling. Most modern engines employ a gudgeon pin offset, and there is a growing interest in pursuing large crank offsets; hence, the effect of these on inertia variation is also of interest. This paper presents the derivation of the inertia function for a single engine mechanism, including both piston-to-cylinder friction and crank or gudgeon pin offset, and investigates the effect of each through predictions. The effect of crank offset on the variable inertia function is also verified by experiment.
APA, Harvard, Vancouver, ISO, and other styles
5

Fabbri, Luca, and Stefano Vignolo. "A torsional completion of gravity for Dirac matter fields and its applications to neutrino oscillations." Modern Physics Letters A 31, no. 03 (January 18, 2016): 1650014. http://dx.doi.org/10.1142/s0217732316500140.

Full text
Abstract:
In this paper, we consider the torsional completion of gravitation for an underlying background filled with Dirac fields, applying it to the problem of neutrino oscillations: we discuss the effects of the induced torsional interactions as corrections to the neutrino oscillations mechanism.
APA, Harvard, Vancouver, ISO, and other styles
6

Wang, Mingyuan, and Lubin Hang. "Research and application of variable DOF compliant five-bar mechanism based on novel compliant torsion joint in vehicle side door latch." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 234, no. 19 (April 20, 2020): 3789–808. http://dx.doi.org/10.1177/0954406220917423.

Full text
Abstract:
In this paper, a novel compliant joint with torsion spring (CJTS) is proposed in order to realize the power release (Note: The “power release” feature means that the closure system with a latch assembly including a pawl-ratchet release mechanism is controlled by at least one electric actuator.) feature of the vehicle side door latch. A new type of variable degree of freedom (DOF) compliant five-bar mechanism (VDCM) based on the novel compliant joint is constructed. The novel compliant mechanism is characterized by multiple motion modes of planar five-bar mechanism and four-joint, crank-shaper, crank-oscillating block mechanism. These motion modes can be switched through the different choices of driving joints and limiting stoppers. This compliant mechanism is effectively implanted into a vehicle side door latch as a sub-branch to perform power release function. The force-adaptive characteristic of the VDCM ensures compatibility with extant manual release branches. Drifting displacement of the CJTS’s torsion spring rotation center in the groove is proposed as a compliant index to describe the compatibility and force-adaptive characteristics under various working modes. The relationship between torsion spring stiffness and mechanism characteristic point motion trajectory or position recovery time duration or motion accuracy is studied. The results show that the introduction of compatibility and force-adaptive characteristics is able to reduce the shaking forces exerted on the mechanism frame. The shaking forces will be further reduced by changing equivalent mass center position of the component. Furthermore, the practicability of the novel compliant mechanism is experimentally validated on the force-displacement test platform. The work in this paper provides a reference for the multi-mode motion mechanical design in a confined space of the latch.
APA, Harvard, Vancouver, ISO, and other styles
7

Nehme, H., N. G. Chalhoub, and N. Henein. "Development of a Dynamic Model for Predicting the Rigid and Flexible Motions of the Crank Slider Mechanism." Journal of Engineering for Gas Turbines and Power 120, no. 3 (July 1, 1998): 678–86. http://dx.doi.org/10.1115/1.2818199.

Full text
Abstract:
A continuous model is developed to predict the rigid and flexible motions of the piston assembly/connecting rod/crankshaft mechanism for a single cylinder engine. The model accounts for the torsional vibration and the out-of-plane transverse deformation of the crankshaft along with the out-of-plane transverse deformation of the connecting rod. The eigenvalue problem of the crankshaft, including the counterweights, the flywheel, and the crank gear, is solved to obtain the analytical expressions for the elastic modes of the crankshaft. The resulting mode shapes are then used in the assumed modes method to approximate the structural flexibility terms. The differential-algebraic equations of motion are obtained by implementing the Lagrange principle. The digital simulation results illustrate the role played by the topological nonlinearities inherent in the system and reveal the relationships with which the rigid and flexible motions of the crank-slider mechanism would interact.
APA, Harvard, Vancouver, ISO, and other styles
8

Kim, Young-Wann, and Kyung-Jo Park. "The interaction of fundamental torsional guided waves from axial and oblique defects in pipes." Insight - Non-Destructive Testing and Condition Monitoring 63, no. 6 (June 1, 2021): 334–40. http://dx.doi.org/10.1784/insi.2021.63.6.334.

Full text
Abstract:
A quantitative study of the interaction of the T(0,1) torsional mode with axial and oblique defects in a pipe is presented in this paper. A mode decomposition technique employing the chirplet transform is used to separate the multimodal signals reflected from the defects. Reflection signals are obtained from experiments on a carbon steel pipe. The influence of the crack length and inclination angle on the reflection is investigated. The reflection from an axial defect is found to consist of a series of wave pulses with gradually decaying amplitude. The results show that the reflection coefficient of an axial crack initially increases with the crack length but finally reaches an oscillating regime. Furthermore, for an oblique crack, it is revealed that the reflection coefficient is linearly dependent on the equivalent circumferential extent of the defect and is independent of the axial length.
APA, Harvard, Vancouver, ISO, and other styles
9

Zaqarashvili, T., and B. Roberts. "Swing Coupling between Stellar Pulsations and Torsional Alfvén Oscillations." International Astronomical Union Colloquium 185 (2002): 484–85. http://dx.doi.org/10.1017/s0252921100016894.

Full text
Abstract:
AbstractWe suggest a mechanism of energy transmission from stellar radial pulsations into torsional oscillations in a dipole-like magnetic field. We show that the stellar radial pulsations cause a periodical variation of the Alfén speed which leads to the Mathieu equation for torsional Alfén waves. Harmonics with half the frequency of the pulsations have exponentially growing amplitudes. Then the energy supporting the various type of pulsations can be transformed into purely electromagnetic oscillations of the star.
APA, Harvard, Vancouver, ISO, and other styles
10

Liu, Siyuan, Wanyou Li, Zhijun Shuai, and Meilong Chen. "Vibration Analysis of a Single-Cylinder Reciprocating Compressor considering the Coupling Effects of Torsional Vibration." Shock and Vibration 2019 (April 1, 2019): 1–9. http://dx.doi.org/10.1155/2019/3904595.

Full text
Abstract:
A piston slap is one of the main vibration sources of the reciprocating machinery. Much work has been done in this field, most of which was based on a constant rotating speed. However, in practice, the speed of a crankshaft may always fluctuate due to the uneven load or excitation. The inertia forces of moving components are much different at the fluctuating rotating speed comparing with that at a constant speed. In this paper, the piston slap and the induced vibration are analyzed based on the instantaneous angular speed measured on a single-cylinder reciprocating compressor. Firstly, the dynamics of a crank-connecting rod mechanism is analyzed based on the measured instantaneous angular speed which contains the torsional vibration of the air compressor. The time histories of piston slap impact forces considering and without considering torsional vibration are compared. Then, in order to correlate the piston slap impact with the slap-induced vibration, the corresponding transfer functions between the middle stroke of the outer surface of the cylinder liner and the excitation points are measured. And the excitation force on the main bearing is also taken into account to bring the simulation closer to the experimental results. The effects of a torsional vibration on the vibration of the cylinder liner are analyzed, and the simulation results show that the torsional vibration is a factor that must be taken into account in the vibration analysis of the single-cylinder reciprocating compressor.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Torsional oscillations of the crank mechanism"

1

Faiman, Jiří. "Tříválcový zážehový motor s excentrickým klikovým mechanismem pro osobní vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231763.

Full text
Abstract:
The first part of this thesis deals with the examination of the eccentricity of the crank mechanism for individual variables kinematics and dynamics of crank mechanism, analyticaly computed in Matlab. Then it compares the different possibilities of balancing moments of inertia forces and propose a specific design chosen for the value of eccentricity. In the second part is designed a model of crankshaft mechanism based on the investigated parameters. These parameters were carried out by structural analysis in Ansys.
APA, Harvard, Vancouver, ISO, and other styles
2

Süttő, Daniel. "Pětiválcový řadový vznětový motor s excentrickým klikovým mechanismem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231456.

Full text
Abstract:
The aim of this thesis is to find out the influence of eccentricity of crank mechanism on the duration of the force between the piston and the cylinder liner. At the same time I wanted to find out its influence on the balance of the whole system. It is important to design the balance for the selected value of the eccentricity and subsequently put through the crank shaft to stress analysis with torsional vibrations. I got so interested in this problem that in addition to the whole topic I designed a torsional vibration damper.
APA, Harvard, Vancouver, ISO, and other styles
3

Pulava, Oleksandr. "Šestiválcový vznětový motor pro užitková vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-378397.

Full text
Abstract:
The aim of this diploma is to design a crankshaft for a six-cylinder commercial vehicle, which is one of the unified motors. The main parts are the design of the crankshaft configuration, the crankshaft balancing method for forces and moments, the crankshaft design documentation, and the crankshaft strength verification. The design of torsional vibration damping characteristics is also made and its effect on torsional vibration and crankshaft strength is determined.
APA, Harvard, Vancouver, ISO, and other styles
4

Novosád, Ivan. "Šestiválcový řadový vznětový motor s vypínáním válců." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417519.

Full text
Abstract:
Master 's thesis deals with design of a drivetrain of six cylinder inline engine with cylinder deactivation for heavy agricultural vehicles. In this thesis were devised various possibilities of crankshaft balancing, the best design solution of counterweight was based on optimization in software Catia. Further, the crankshaft was analysed for force and momentum loading and torsional vibration, based on which, the torsional vibration damper was designed. There were considered several options for cylinder deactivation, which were analysed for finest run of engine and the best thermal distribution. Based on these criteria, the best option was to deactivate 2nd and 5th cylinder. The crankshaft was analysed for the fatigue failure by finite element method. The fatigue failure is the most dangerous case for the crankshaft, the resulting safety factor for this limit state is 3,05.
APA, Harvard, Vancouver, ISO, and other styles
5

Freisleben, Pavel. "Dvouválcový zážehový motor s excentrickým klikovým mechanismem pro osobní vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232115.

Full text
Abstract:
This thesis deals with forces of the crank mechanism. The aim of this work is to find the right value of the eccentricity of the crank mechanism, which will have a positive effect on the size and course of forces that cause friction losses in the crank mechanism. Next solves this balancing eccentric unit. The last part deals with the design and strength check of the crankshaft considering torsional vibration.
APA, Harvard, Vancouver, ISO, and other styles
6

Nikolaychuk, Yaroslav. "Čtyřválcový vznětový motor pro užitková vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-377457.

Full text
Abstract:
The diploma thesis focuses on the design of the crankshaft for a four-cylinder diesel engine for commercial vehicles, the main task of this work are the design configuration of the crankshaft balance inertia forces and torques at the crank mechanism, drawing documentation crankshaft design strength check considering torsional vibration.
APA, Harvard, Vancouver, ISO, and other styles
7

Švarc, Marek. "Pětiválcový vznětový motor pro užitková vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318711.

Full text
Abstract:
The aim of this diploma thesis is the design of the configuration and the method of balancing the crank mechanism with the specified parameters. For a particular configuration, a crankshaft drawing is processed and a strength analysis, considering the crankshaft torsional vibrations is performed in Ansys FEM software. At the end of the thesis, an ideological design of the torsional vibration damper and its effect on the crankshaft stress in the Ansys FEM software is performed.
APA, Harvard, Vancouver, ISO, and other styles
8

Černohous, Tomáš. "Dvouválcový řadový vznětový motor s excentrickým klikovým mechanismem pro užitková vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232050.

Full text
Abstract:
The goal of this master’s thesis is to examine the influence of eccentricity on the behaviour of forces between the piston and cylinder liner and on balancing of the crank mechanism for given parameters of the diesel engine. Another aim of this paper is to propose an appropriate balancing of the crank mechanism followed by stress analysis considering torsional vibration for a chosen value of eccentricity.
APA, Harvard, Vancouver, ISO, and other styles
9

Steigl, Vladimír. "Čtyřválcový zážehový motor s vypínáním válců." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318839.

Full text
Abstract:
The aim of this diploma thesis is design of configuration and balancing of crankshaft which is determined for four-cylinder gasoline engine. The thesis investigates kinematics, dynamics and possible ways of balancing the inertial forces and moments of the rotating and sliding parts of the central crank mechanism. Subsequently, the 3D CAD model is designed according to the presented drawing. It is transformed into a spare torsion system, from which the calculations of its own and forced torsional vibrations are based. The proposed 3D CAD model is then spatially transmitted in the FEA software Ansys Workbench and modified (boundary conditions, etc.) in the FEA software Ansys Mechanical APDL so that it can be calculated according to the selected LSA method. From the selected results of the LSA method, the crankshaft safety factor against fatigue damage is calculated.
APA, Harvard, Vancouver, ISO, and other styles
10

Kučera, Ondřej. "Čtyřválcový řadový zážehový letecký motor." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-444959.

Full text
Abstract:
The thesis deals with the structural design of a steel connecting rod for the aircraft engine Walter Mikron III, which is currently still manufactured and developed by company PARMA-TECHNIK, s.r.o. The proposed connecting rod would replace the current duralumin connecting rod. The work also contains a strength analysis of the designed component, in which it was aimed to verify the stress on the connecting rod, based on which the fatigue safety factor was performed. This is crucial for dynamically stressed parts of internal combustion engines. Furthermore, was investigated the effect of the change of the connecting rod on the torsional vibration of the crank mechanism. For this purpose, was built a discrete torsion model. The output of the whole work is the drawing documentation of the new connecting rod, meeting the requirements for application in an aircraft engine.
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Torsional oscillations of the crank mechanism"

1

Lanets, Oleksii, Oleksandr Kachur, Vitaliy Korendiy, and Vasyl Lozynskyy. "Controllable Crank Mechanism for Exciting Oscillations of Vibratory Equipment." In Lecture Notes in Mechanical Engineering, 43–52. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-77823-1_5.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Torsional oscillations of the crank mechanism"

1

Beale, David G., and Shyr Wen Lee. "Linear and Nonlinear Instabilities in a Flexible Mechanism." In ASME 1993 Design Technical Conferences. American Society of Mechanical Engineers, 1993. http://dx.doi.org/10.1115/detc1993-0098.

Full text
Abstract:
Abstract An analytical and experimental comparison is made between the stability of the linear and nonlinear equation response of a flexible rod in a slider crank mechanism, using a one mode approximation. It is shown that there is strong correlation between the onset of parametric resonance regions from the linear equation and the bifurcation of a stable period 1 solution from the nonlinear equation, both regions plotted on a crank length-crank speed parameter plane. But within the unstable zones, an estimate of response requires a nonlinear equation representation. Amplified oscillations, not associated with any instability and called irregular resonance when pertaining to the nonlinear equations, are also present as harmonics in the linear equation analysis. The nonlinearities effect these resonances by pulling the peak amplification to lower speeds.
APA, Harvard, Vancouver, ISO, and other styles
2

Avanço, Rafael H., Hélio A. Navarro, Reyolando M. L. R. F. Brasil, and José M. Balthazar. "Nonlinear Dynamics of a Pendulum Excited by a Crank-Shaft-Slider Mechanism." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-36643.

Full text
Abstract:
In this analysis, we consider the dynamics of a pendulum under vertical excitation of a crank-shaft-slider mechanism. The nonlinear model approaches that of a classical parametrically excited pendulum when the ratio of the length of the shaft to the radius of the crank is very large. Numerical techniques are employed to investigate the results for different parameters and initial conditions. Lyapunov exponents, bifurcation diagrams, time histories and phase portraits are presented to explore conditions when the pendulum performs or not full rotations. Of special interest are the resonance regions. Rotations together with oscillations and chaos were observed in some resonance zones.
APA, Harvard, Vancouver, ISO, and other styles
3

Ahmed, Zakia, Sevak Tahmasian, and Craig A. Woolsey. "Vibrational Control of a 2-Link Mechanism." In ASME 2020 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/dscc2020-3257.

Full text
Abstract:
Abstract This paper describes vibrational control and stability of a planar, horizontal 2-link mechanism using translational control of the base pivot. The system is a 3-DOF two-link mechanism that is subject to torsional damping, torsional stiffness, and is moving on a horizontal plane. The goal is to drive the averaged dynamics of the system to a desired configuration using a high-frequency, high-amplitude force applied at the base pivot. The desired configuration is achieved by applying an amplitude and angle of the input determined using the averaged dynamics of the system. We find the range of stable configurations that can be achieved by the system by changing the amplitude of the oscillations for a fixed input angle and oscillation frequency. The effects of varying the physical parameters on the achievable stable configurations are studied. Stability analysis of the system is performed using two methods: the averaged dynamics and averaged potential.
APA, Harvard, Vancouver, ISO, and other styles
4

Zirbel, Shannon A., Quentin T. Aten, Melanie Easter, Brian D. Jensen, and Larry L. Howell. "Compliant Constant-Force Micro-Mechanism for Enabling Dual-Stage Motion." In ASME 2012 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/detc2012-70321.

Full text
Abstract:
This paper describes a fully compliant constant-force micro-mechanism that enables dual-stage motion for nanoinjection. Nanoinjection is a recently developed process for delivering DNA into mouse zygotes via electrostatic accumulation and release of the DNA onto a microelectromechanical system (MEMS) lance. The fully compliant constant-force nanoinjector is a concatenation of two separate mechanisms: a six-bar mechanism with compliant lamina-emergent torsional (LET) joints to raise the lance, and a pair of constant-force crank-sliders with LET joints positioned on either side of the six-bar mechanism to drive the lance forward. The fully compliant nanoinjector exhibits self-reconfiguring metamorphic motion to first raise the lance to the midline of the zygote and then translate the lance forward with a controlled motion. This dual-stage motion is necessary for the lance to pierce the zygote without causing damage to the cell membrane. The device achieves two sequential displacement behaviors in a compliant mechanism fabricated from a single, continuous piece of material.
APA, Harvard, Vancouver, ISO, and other styles
5

Kurnool, Sirihari, and Cemil Bagei. "Critical Speed Analysis of Multi-Cylider Engines As Spatial Elastic Linkage Systems." In ASME 1996 Design Engineering Technical Conferences and Computers in Engineering Conference. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-detc/mech-1191.

Full text
Abstract:
Abstract A multi-cylinder engine is a cluster of slider-crank linkages. Presently used conventional pure torsional shaft models predict results far from the results predicted considering actual three-dimensional linkage and crankshaft geometries. Pure torsional model doesn’t sense the variation in frequency with the variation in engine geometry. It predicts one constant frequency value for each mode; it does not permit the use of flexible bearings. Article offers a finite element method for performing frequency and critical speed analysis of multi-cylinder engines considering three-dimensional geometries of the linkage loops, crankshaft, and the crankshaft throws, as a spatial elastic mechanism system. Any number of cylinders in any angular orientations with respect to each other may be considered. A three-dimensional flexural finite-line element with isoparametric joint freedom irregularity is developed and used to formulate the eigenvalue equations of motion for the system. Consistent mass matrix as well as lumped mass matrix methods can be used. The element can be restrained to perform coupled torsional and flexural or pure torsional frequency analysis of geared rotor model of engines and shafts on many rigid or flexible bearings. Geared connections can also be considered flexible. A generalized computer program is made available for industrial use. It determines frequencies, mode shapes and critical speed bands of an engine for complete crankshaft rotation for as many modes as desired. The frequency and critical speed analysis of a four-cylinder MGB automobile engine with in-plane crank throws, with and without bearing flexibilities, is performed and the results are compared with those obtained using the conventional pure torsional shaft model. Geared tandem ship drive system is studied to test the reliability of the developments.
APA, Harvard, Vancouver, ISO, and other styles
6

Starns, Gloria K., and Donald R. Flugrad. "Synthesis of a Large Oscillation Four-Bar Mechanism." In ASME 1997 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/detc97/dac-3854.

Full text
Abstract:
Abstract This paper demonstrates procedures implemented for the synthesis of a four-bar mechanism that produces large angular oscillations of the output member while maintaining effective transmission angles. The mechanisms are modeled as being driven by a force applied at the coupler link. Additionally this force’s line of action is constrained to occur along an approximate straight line. This research was conducted out of the need for a device that is capable of retraction of the horizontal tool bar housed on the back of a tractor. The tool bars accommodate the implements required to accomplish the numerous tasks of the farmer, i.e. row markers, sprayer arms, planters, etc. Upon retraction of the tool bar so that it is parallel to ground, the appropriate tools are lowered to their working position. As the length of these bars increases, a savings of time and increased productivity is realized. Kurt Hain makes the following observation regarding large oscillation mechanisms in [1]: “It would be very difficult to solve this problem with one four-bar linkage, because it is difficult to design a four-bar linkage having such a large oscillation of a crank without running into problems of poor transmission angle characteristics; it might be possible to use linkages in combinations with gears, but this would make the mechanism more expensive, less efficient, and probably noisier.” In this study simulated annealing, a genetic algorithm and the generalized reduced gradient method are used to produce mechanisms with large angular oscillations of the output member and transmission angles that vary by as little as 20° from 90°. A comparative analysis of each of the optimization procedures is presented with observations regarding the efficacy of each method in the solution of the large oscillation mechanism.
APA, Harvard, Vancouver, ISO, and other styles
7

Huera-Huarte, Francisco J., and Zafar A. Bangash. "DPIV Around a Flexible Circular Cylinder Undergoing Cross-Flow Forced Oscillations." In ASME 2012 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/pvp2012-78535.

Full text
Abstract:
This research is motivated by early experiments [1, 2], in which the main time consistent flow structures in the wake of a flexible oscillating circular cylinder were studied. We have now investigated the wake of a circular cylinder undergoing forced vibrations, by using Planar Digital Particle Image Velocimetry (DPIV) and long exposure photographs for flow visualisation. The focus is given to the node to anti-node transition when the cylinder oscillates in its second structural mode. A flexible cylinder is supported by a structure consisting of a frame that includes a motor that drives a shaft, that actuates a pusher connected to the cylinder at two points, through a crank slider mechanism. We are able to produce forced oscillations of the cylinder, either in its first mode when the pushers are in phase, or in its second mode if the pushers are configured out-of-phase. We have used a high speed camera together with a continuous wave laser, to image seeding particles being illuminated by the laser sheet, at two different heights along the length of the cylinder: the node and the anti-node. We have also produced long exposure images of the particles leading to flow visualisation.
APA, Harvard, Vancouver, ISO, and other styles
8

Kfoury, G. A., N. G. Chalhoub, N. A. Henein, and W. Bryzik. "Enhancement of the Accuracy of the Modified (P–ω) Method Through the Implementation of a Nonlinear Robust Observer." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-80115.

Full text
Abstract:
The original version of the (P–ω) method is a model-based approach developed for determining the instantaneous friction torque in internal combustion engines. This scheme requires measurements of the cylinder gas pressure, the engine load torque, the crankshaft angular displacement and its time derivatives. The effects of the higher order dynamics of the crank-slider mechanism on the measured angular motion of the crankshaft have caused the (P–ω) method to yield erroneous results, especially, at high engine speeds. To alleviate this problem, a nonlinear sliding mode observer has been developed herein to accurately estimate the rigid and flexible motions of the piston-assembly/connecting-rod/crankshaft mechanism of a single cylinder engine. The observer has been designed to yield a robust performance in the presence of disturbances and modeling imprecision. The digital simulation results, generated under transient conditions that represent a decrease in the engine speed, have illustrated the rapid convergence of the estimated state variables to the actual ones in the presence of both structured and unstructured uncertainties. Moreover, this study has proven that the use of the estimated rather than the measured angular displacement of the crankshaft and its time derivatives can significantly improve the accuracy of the (P–ω) method in determining the instantaneous engine friction torque. However, the effects of structural deformations of the crank-slider mechanism have rendered the original version of the (P–ω) method to be inapplicable at high engine speeds. This problem has been addressed herein by modifying the formulation of the (P–ω) method in order to account for the first two elastic modes of the crankshaft torsional vibration. The simulation results confirm the good performance of the modified (P–ω) method in determining the instantaneous friction torque at high engine speeds.
APA, Harvard, Vancouver, ISO, and other styles
9

Larochelle, Pierre, and J. M. McCarthy. "Static Analysis of Spherical nR Kinematic Chains With Joint Friction." In ASME 1992 Design Technical Conferences. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/detc1992-0377.

Full text
Abstract:
Abstract This paper presents the static analysis of general spherical nR simple open or closed kinematic chains with joint friction. The internal loading on each link is found to consist of a bending moment and a torsional moment. The goal of this analysis is to determine these moments which are then used in designing the link. The moment and force balance equations for each link yields a linear system of equations which define the internal moments of the mechanism and the output torque on the driven crank for a given input torque. A Coulomb model of joint friction is used to determine the friction torque along the axis of a joint. The joint friction model requires an iterative solution. The purpose of this algorithm is to provide a means of computing the complete internal and external loading on the members of spherical chains while including frictional effects in order to facilitate the design of a functional spherical mechanisms.
APA, Harvard, Vancouver, ISO, and other styles
10

Arafat, Haider N., and Ali H. Nayfeh. "Transfer of Energy From High- to Low-Frequency Modes in the Bending-Torsion Oscillation of Cantilever Beams." In ASME 1999 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/detc99/vib-8159.

Full text
Abstract:
Abstract We investigate the nonlinear bending-torsion response of a cantilever beam to a transverse harmonic excitation, where the forcing frequency is near the natural frequency of the first torsional mode. We analyze the case where the first in-plane bending mode is activated by a nonresonant mechanism. We use the method of time-averaged Lagrangian and virtual work to determine the equations governing the modulations of the phases and amplitudes of the interacting modes. These equations are then used to investigate the nonlinear behavior of limit-cycle oscillations of the beam as the excitation amplitude is slowly varied. As an example, we consider the response of an aluminum beam for which the natural frequency of the first in-plane bending mode is fv1 ≈ 5.7 Hz and the natural frequency of the first torsional mode is fϕ1 ≈ 138.9 Hz.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Torsional oscillations of the crank mechanism' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography