Model for the Force–Displacement Relationship of Wire Rope Springs

2008 ◽  
Vol 21 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Rafik R. Gerges
Keyword(s):  
Wire Rope ◽  
Relationship Of ◽  
Force Displacement

Semi-inverse method for predicting stress–strain relationship from cone indentations

2003 ◽  
Vol 18 (9) ◽  
pp. 2068-2078 ◽  
Author(s):  
A. DiCarlo ◽  
H. T. Y. Yang ◽  
S. Chandrasekar
Keyword(s):  
A Priori ◽  
Model Material ◽  
Material Behavior ◽  
The Finite Element Method ◽  
Stress Strain ◽  
Indentation Tests ◽  
Strain Relationship ◽  
Initial Force ◽  
Relationship Of ◽  
Force Displacement

A method for determining the stress–strain relationship of a material from hardness values H obtained from cone indentation tests with various apical angles is presented. The materials studied were assumed to exhibit power-law hardening. As a result, the properties of importance are the Young's modulus E, yield strength Y, and the work-hardening exponent n. Previous work [W.C. Oliver and G.M. Pharr, J. Mater. Res. 7, 1564 (1992)] showed that E can be determined from initial force–displacement data collected while unloading the indenter from the material. Consequently, the properties that need to be determined are Y and n. Dimensional analysis was used to generalize H/E so that it was a function of Y/E and n [Y-T. Cheng and C-M. Cheng, J. Appl. Phys. 84, 1284 (1999); Philos. Mag. Lett. 77, 39 (1998)]. A parametric study of Y/E and n was conducted using the finite element method to model material behavior. Regression analysis was used to correlate the H/E findings from the simulations to Y/E and n. With the a priori knowledge of E, this correlation was used to estimate Y and n.

Dynamics of Deformable Fractal Surface in Contact with Harmonically Excited Rigid Flat

2017 ◽  
Vol 7 (2) ◽  
pp. 38-62
Author(s):  
Tamonash Jana ◽  
Anirban Mitra ◽  
Prasanta Sahoo
Keyword(s):  
Rough Surface ◽  
Dynamic Properties ◽  
Element Model ◽  
Harmonic Excitation ◽  
System Response ◽  
Fractal Surface ◽  
Fractal Rough Surface ◽  
Mass Damper ◽  
Relationship Of ◽  
Force Displacement

Dynamics of contact between a deformable fractal rough surface and a rigid flat is studied under harmonic excitation to the flat surface. Fractal surface is generated from the modified Weierstrass-Mandelbrot function and is imported to ANSYS to construct the finite element model of the same. A parameter called ‘nonlinearity exponent', is obtained from the force-displacement relationship of the rough surface and is used to find out the dynamic properties of the contacting interface using single spring-mass-damper model. The effect of variation in surface roughness and material properties on the system response is analyzed. The system exhibits superharmonic responses for different values of the nonlinearity exponent. The phase plot and time-displacement plots for the system are also furnished.

An Analytical Model for the Stiffness of Slotted Disk Springs

2020 ◽  
pp. 2050120
Author(s):  
Junshan Wang ◽  
Lei Jian ◽  
Weijie Leng ◽  
Chongmin She ◽  
Zhijun Sun
Keyword(s):  
Analytical Model ◽  
Shell Theory ◽  
Beam Theory ◽  
Displacement Transducer ◽  
Ultrasonic Motors ◽  
Proposed Model ◽  
Disk Spring ◽  
Accuracy Parameter ◽  
Relationship Of ◽  
Force Displacement

The slotted disk spring is an important part of ultrasonic motors. Its mechanical properties directly affect the running stability of the motor. In this study, an analytical model is developed to solve the preload problem for slotted disk springs used in ultrasonic motors. The outer conical ring of the slotted disk spring is modeled using the conical shell theory. The inner separated teeth are modeled by the cantilever beam theory. An analytical mechanical model for the force-displacement relationship of the entire slotted disk spring is then developed. The results of the experiment based on a force-displacement transducer and the results from the analytical model, a finite element calculation, and the Schremmer formula are compared to validate the analytical model. The results show that the proposed model has the highest accuracy. Parameter-sensitivity analysis for the slotted disk spring is finally performed, and a new slotted disk spring with a long zero-stiffness interval is designed for a 40[Formula: see text]mm traveling wave rotary ultrasonic motor.

Application of force-monitor ultrasonography to assess distal radioulnar joint instability in patients with triangular fibrocartilage complex injury

Ultrasound ◽  
2021 ◽  
pp. 1742271X2110383
Author(s):  
Hiroshi Yuine ◽  
Yuichi Yoshii ◽  
Koichi Iwai ◽  
Tomoo Ishii ◽  
Hideki Shiraishi
Keyword(s):  
Dorsal Surface ◽  
Distal Radioulnar Joint ◽  
Triangular Fibrocartilage Complex ◽  
Healthy Controls ◽  
Radioulnar Joint ◽  
Ulnar Head ◽  
Force Ratio ◽  
Triangular Fibrocartilage ◽  
Relationship Of ◽  
Force Displacement

Introduction In this study, we evaluated the differences and measurement accuracy in the force–displacement relationship of the distal radioulnar joint (DRUJ) between patients with triangular fibrocartilage complex (TFCC) injury and healthy controls using force-monitor ultrasonography. Methods This study included 11 TFCC injury patients and 22 healthy controls. We evaluated differences in the force–displacement relationship of the DRUJ in these patients using force-monitor ultrasonography. Cyclic compression was applied to the dorsal surface of the ulnar head. Distance between the dorsal surface of the distal radius and ulnar head at the DRUJ level was measured in the initial and pressed-down positions. Changes in radioulnar displacement, applied force, and displacement-to-force ratio were measured. Furthermore, we compared the parameters between the affected and unaffected wrists and between TFCC injury patients and controls. Results The radioulnar displacement and displacement-to-force ratio were significantly larger in the affected wrists than in the unaffected wrists ( P =  0.003 and P =  0.02). The affected/unaffected side ratio of radioulnar displacement and displacement-to-force ratio were significantly larger in the TFCC injury patients than in the controls ( P =  0.003 and P =  0.02). The area under the curve was 0.82 for the affected/unaffected ratio of the radioulnar displacement. The optimal cutoff value indicated by the receiver-operating characteristic curve for the affected/unaffected ratio of the radioulnar displacement was 1.71; the sensitivity and specificity were 82% and 86%, respectively. Conclusions Assessing the DRUJ instability with force-monitor ultrasonography may help identify TFCC-injured wrists.

Development of a Multi-Ball-Cantilever AFM for Measuring Resist Surface

2006 ◽  
Vol 18 (6) ◽  
pp. 698-704 ◽  
Author(s):  
Shujie Liu ◽  
◽  
Shuichi Nagasawa ◽  
Satoru Takahashi ◽  
Kiyoshi Takamasu
Keyword(s):  
High Speed ◽  
Surface Deformation ◽  
Surface Profile ◽  
Displacement Curve ◽  
The Finite Element Method ◽  
Measuring Surface ◽  
Surface Profiles ◽  
Relationship Of ◽  
The Relationship ◽  
Force Displacement

Semiconductor processing must be fast and highly accurate when measuring the surface profile of soft thin films such as photoresists. We propose doing so using a multi-ball-cantilever AFM, which covers a wide area at high speed. Each cantilever has a ball stylus with a diameter that does not plastically deform measured surfaces. We studied resist profiles and the influence of the AFM stylus on the resist surface. To verify our proposal’s feasibility, we simulated the relationship of the indenter shape, size, and load and resist surface deformation using the finite element method (FEM). We discuss the influence of the AFM stylus based on the force-displacement curve. Experiments using the multi-ball-cantilever AFM confirmed its feasibility for measuring surface profiles highly accurately.

Simulation Method of Soil Resistance on the Pushover Model of Group Pile Foundations

2012 ◽  
Vol 204-208 ◽  
pp. 981-985
Author(s):  
Yong Liang Zhang ◽  
Tian Bao Li
Keyword(s):  
Pile Foundation ◽  
Pushover Analysis ◽  
Simulation Method ◽  
Small Displacement ◽  
Advantages And Disadvantages ◽  
Elasto Plasticity ◽  
Nonlinear Force ◽  
Relationship Of ◽  
Force Displacement ◽  
Group Pile

Soil is a strong non-linear media and show obvious nonlinear under the small displacement of the foundation. Under the strong earthquake, the seismic performance of group pile foundation is closely related to the nonlinear force-displacement relationship of soil around the pile foundation and the elasto-plasticity o fpile. This paper introduces the nonlinear static pushover analysis of group pile foundation , summarizes the commonly used simulation method of soil around the pile foundation and compares the advantages and disadvantages of various simulation method.

scholarly journals Effect of shear modulus on the performance of prototype un-bonded fiber reinforced elastomeric isolators

2018 ◽  
Vol 12 (5) ◽  
pp. 10-19
Author(s):  
Van Thuyet Ngo
Keyword(s):  
Shear Modulus ◽  
Horizontal Displacement ◽  
Fe Analysis ◽  
Light Weight ◽  
Fiber Reinforced ◽  
Base Isolator ◽  
Elastomeric Isolator ◽  
Fiber Reinforced Elastomeric Isolator ◽  
Relationship Of ◽  
Force Displacement

Un-bonded fiber reinforced elastomeric isolator (U-FREI) is light weight and facilitates easier installation in comparison to conventional steel reinforced elastomeric isolators (SREI), in which fiber layers are used as reinforcement to replace steel shims as are normally used in conventional isolators. Shear modulus of elastomer has significant influence on the force-displacement relationship of U-FREI. However, a few studies investigated the effect of shear modulus on the horizontal behavior of prototype U-FREI in literature. In this study, effect of shear modulus on performance of prototype U-FREIs is investigated by both experiment and finite element (FE) analysis. It is observed that reduction in horizontal stiffness of U-FREI with increasing horizontal displacement is due to both rollover deformation (or reduction in contact area of isolator with supports) and shear modulus of elastomer. Reasonable agreement is observed between the findings from experiment and FE analysis. Keywords: base isolator; prototype un-bonded fiber reinforced elastomeric isolator; rollover deformation; shear modulus; cyclic test.

Sign in / Sign up

Export Citation Format

Share Document