Log in

Relevant bibliographies by topics / Fiber kinematics / Journal articles

To see the other types of publications on this topic, follow the link: Fiber kinematics.

Journal articles on the topic 'Fiber kinematics'

Author: Grafiati

Published: 23 September 2022

Last updated: 22 October 2022

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

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Fiber kinematics.'

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.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Amancharla, Maneesh R., Joseph R. Rodarte, and Aladin M. Boriek. "Modeling the kinematics of the canine midcostal diaphragm." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 280, no. 2 (February 1, 2001): R588—R597. http://dx.doi.org/10.1152/ajpregu.2001.280.2.r588.

Full text

Abstract:

The hypotheses that the chest wall insertion (CW) is displaced laterally during inspiration and that this displacement is essential in maintaining muscle curvature of the costal diaphragmatic muscle fibers were tested. With the use of data from three dogs, caudal, lateral, and ventral displacements of CW during both quiet, spontaneous inspiration and during inspiratory efforts against an occluded airway were observed and recorded. We have developed a kinematic model of the diaphragm that incorporates these displacements. This model describes the motions of the muscle fibers and central tendon; the displacements of the midplane, muscle-tendon junction (MTJ), CW, and center of the muscle fiber-central tendon arcs are modeled as functions of muscle fiber length. In the model, the center of the fiber arcs and MTJ both move caudally parallel to the midplane during inspiration, whereas CW moves both caudally and laterally. The observed lateral displacement of CW and the observed caudal displacement of MTJ, as functions of muscle fiber length, both approximate well the theoretical displacements that would be necessary to maintain curvature of the fiber arcs. In confirming our hypotheses, we have found that lateral displacement of CW is a mechanism by which changes in the shape of the costal diaphragm, as described by its curvature, are limited.

APA, Harvard, Vancouver, ISO, and other styles

2

Nguyen, Ngan Hong. "FIBER CUTTING MACHINE USED FOR COMPOSIT MATERIAL." Science and Technology Development Journal 13, no. 2 (June 30, 2010): 37–48. http://dx.doi.org/10.32508/stdj.v13i2.2116.

Full text

Abstract:

This paper proposes a structure and kinematics parameters of a fiber cutting machine, which is used to cut fibers (such as jute fiber, bamboo fiber, coconut fiber...) for composite materials. To come over this obstacle, dynamic and geometric parameters of cutting parts were calculated and studied, some fibers physico-mechanical properties and their effect in the quality of the composite materials were investigated.

APA, Harvard, Vancouver, ISO, and other styles

3

Park, Jang Min, and Seong Jin Park. "Modeling and Simulation of Fiber Orientation in Injection Molding of Polymer Composites." Mathematical Problems in Engineering 2011 (2011): 1–14. http://dx.doi.org/10.1155/2011/105637.

Full text

Abstract:

We review the fundamental modeling and numerical simulation for a prediction of fiber orientation during injection molding process of polymer composite. In general, the simulation of fiber orientation involves coupled analysis of flow, temperature, moving free surface, and fiber kinematics. For the governing equation of the flow, Hele-Shaw flow model along with the generalized Newtonian constitutive model has been widely used. The kinematics of a group of fibers is described in terms of the second-order fiber orientation tensor. Folgar-Tucker model and recent fiber kinematics models such as a slow orientation model are discussed. Also various closure approximations are reviewed. Therefore, the coupled numerical methods are needed due to the above complex problems. We review several well-established methods such as a finite-element/finite-different hybrid scheme for Hele-Shaw flow model and a finite element method for a general three-dimensional flow model.

APA, Harvard, Vancouver, ISO, and other styles

4

Abisset-Chavanne, Emmanuelle, Rabih Mezher, and Francisco Chinesta. "Two-Scales Kinetic Theory Model of Short-Fibers Aggregates." Key Engineering Materials 554-557 (June 2013): 391–401. http://dx.doi.org/10.4028/www.scientific.net/kem.554-557.391.

Full text

Abstract:

This paper proposes a first attempt to define a two scales kinetic theory to describe concentrated suspensions involving short fibers, nano-fibers or nanotubes. In this case, fiber-fiber interactions can not be neglected and rich microstructures issued from these interactions can be observed, involving a diversity of fibers clusters or aggregates with complex kinematics, and different sizes and shapes. These clusters can interact to create larger clusters and also break because the flow induced hydrodynamic forces. In this paper we propose a double-scale model to describe such microstructure: at the finest scale we study the cluster kinematic based on the behaviour of the rods that constitute it, at a coarser scale, we use clusters distribution to derive the effect of the clusters presence on the suspensions properties.

APA, Harvard, Vancouver, ISO, and other styles

5

Gilbert, Thomas W., Michael S. Sacks, Jonathan S. Grashow, Savio L. Y. Woo, Stephen F. Badylak, and Michael B. Chancellor. "Fiber Kinematics of Small Intestinal Submucosa Under Biaxial and Uniaxial Stretch." Journal of Biomechanical Engineering 128, no. 6 (May 13, 2006): 890–98. http://dx.doi.org/10.1115/1.2354200.

Full text

Abstract:

Improving our understanding of the design requirements of biologically derived collagenous scaffolds is necessary for their effective use in tissue reconstruction. In the present study, the collagen fiber kinematics of small intestinal submucosa (SIS) was quantified using small angle light scattering (SALS) while the specimen was subjected to prescribed uniaxial or biaxial strain paths. A modified biaxial stretching device based on Billiar and Sacks (J. Biomech., 30, pp. 753–7, 1997) was used, with a real-time analysis of the fiber kinematics made possible due to the natural translucency of SIS. Results indicated that the angular distribution of collagen fibers in specimens subjected to 10% equibiaxial strain was not significantly different from the initial unloaded condition, regardless of the loading path (p=0.31). Both 10% strip biaxial stretch and uniaxial stretches of greater than 5% in the preferred fiber direction led to an increase in the collagen fiber alignment along the same direction, while 10% strip biaxial stretch in the cross preferred fiber direction led to a broadening of the distribution. While an affine deformation model accurately predicted the experimental findings for a biaxial strain state, uniaxial stretch paths were not accurately predicted. Nonaffine structural models will be necessary to fully predict the fiber kinematics under large uniaxial strains in SIS.

APA, Harvard, Vancouver, ISO, and other styles

6

Thomopoulos, Stavros, Gregory M. Fomovsky, Preethi L. Chandran, and Jeffrey W. Holmes. "Collagen Fiber Alignment Does Not Explain Mechanical Anisotropy in Fibroblast Populated Collagen Gels." Journal of Biomechanical Engineering 129, no. 5 (February 15, 2007): 642–50. http://dx.doi.org/10.1115/1.2768104.

Full text

Abstract:

Many load-bearing soft tissues exhibit mechanical anisotropy. In order to understand the behavior of natural tissues and to create tissue engineered replacements, quantitative relationships must be developed between the tissue structures and their mechanical behavior. We used a novel collagen gel system to test the hypothesis that collagen fiber alignment is the primary mechanism for the mechanical anisotropy we have reported in structurally anisotropic gels. Loading constraints applied during culture were used to control the structural organization of the collagen fibers of fibroblast populated collagen gels. Gels constrained uniaxially during culture developed fiber alignment and a high degree of mechanical anisotropy, while gels constrained biaxially remained isotropic with randomly distributed collagen fibers. We hypothesized that the mechanical anisotropy that developed in these gels was due primarily to collagen fiber orientation. We tested this hypothesis using two mathematical models that incorporated measured collagen fiber orientations: a structural continuum model that assumes affine fiber kinematics and a network model that allows for nonaffine fiber kinematics. Collagen fiber mechanical properties were determined by fitting biaxial mechanical test data from isotropic collagen gels. The fiber properties of each isotropic gel were then used to predict the biaxial mechanical behavior of paired anisotropic gels. Both models accurately described the isotropic collagen gel behavior. However, the structural continuum model dramatically underestimated the level of mechanical anisotropy in aligned collagen gels despite incorporation of measured fiber orientations; when estimated remodeling-induced changes in collagen fiber length were included, the continuum model slightly overestimated mechanical anisotropy. The network model provided the closest match to experimental data from aligned collagen gels, but still did not fully explain the observed mechanics. Two different modeling approaches showed that the level of collagen fiber alignment in our uniaxially constrained gels cannot explain the high degree of mechanical anisotropy observed in these gels. Our modeling results suggest that remodeling-induced redistribution of collagen fiber lengths, nonaffine fiber kinematics, or some combination of these effects must also be considered in order to explain the dramatic mechanical anisotropy observed in this collagen gel model system.

APA, Harvard, Vancouver, ISO, and other styles

7

Andric, Jelena, Stefan Lindstrom, Srdjan Sasic, and Håkan Nilsson. "Particle-level simulations of flocculation in a fiber suspension flowing through a diffuser." Thermal Science 21, suppl. 3 (2017): 573–83. http://dx.doi.org/10.2298/tsci160510185a.

Full text

Abstract:

We investigate flocculation in dilute suspensions of rigid, straight fibers in a decelerating flow field of a diffuser. We carry out numerical studies using a particle-level simulation technique that takes into account the fiber inertia and the non-creeping fiber-flow interactions. The fluid flow is governed by the Reynolds-averaged Navier-Stokes equations with the standard k-omega eddy-viscosity turbulence model. A one-way coupling between the fibers and the flow is considered with a stochastic model for the fiber dispersion due to turbulence. The fibers interact through short-range attractive forces that cause them to aggregate into flocs when fiber-fiber collisions occur. We show that ballistic deflection of fibers greatly increases the flocculation in the diffuser. The inlet fiber kinematics and the fiber inertia are the main parameters that affect fiber flocculation in the prediffuser region.

APA, Harvard, Vancouver, ISO, and other styles

8

Kholinne, Erica, Rizki Fajar Zulkarnain, Hyun-Joo Lee, Arnold Adikrishna, and In-Ho Jeon. "Functional Classification of the Medial Ulnar Collateral Ligament: An In Vivo Kinematic Study With Computer-Aided Design." Orthopaedic Journal of Sports Medicine 6, no. 3 (March 1, 2018): 232596711876275. http://dx.doi.org/10.1177/2325967118762750.

Full text

Abstract:

Background: It has been widely accepted that the anterior and posterior bundles of the medial ulnar collateral ligament (MUCL) tighten at extension and flexion, respectively. However, this belief is based on anatomic data acquired from cadaveric studies. The advancement of 3-dimensional (3D) model technology has made possible the simulation of dynamic movement that includes each ligament bundle fiber to analyze its functional properties. To date, no study has analyzed ligament kinematics at the level of the fibers while also focusing on their functional properties. Purpose: To propose a new classification for functional properties of the MUCL based on its kinematic pattern. Study Design: Descriptive laboratory study. Methods: Five healthy elbow joints were scanned by use of computed tomography, and 3D models were rendered and translated into vertex points for further mathematical analysis. The humeral origin and ulnar insertion of the MUCL fiber groups were registered. Each vertex point on the origin side was randomly connected to the insertion side, with each pair of corresponding points defined as 1 ligament fiber. Lengths of all the fibers were measured at 1° increments of elbow range of motion (ROM). Ligament fibers were grouped according to their patterns. Mean coverage area for each group, expressed as the percentage of ligament fibers per group to the total number of fibers, was calculated. Results: Four major bundle groups were found based on fiber length properties. Kinematic simulation showed that each group had a different kinematic function throughout elbow ROM. Mean coverage area of groups 1, 2, 3, and 4 was 8% ± 4%, 10% ± 5%, 42% ± 6%, and 40% ± 8%, respectively. Each group acted as a dominant stabilizer in certain arcs of motion. Reciprocal activity was observed between groups 1 and 3 along with groups 2 and 4 to produce synergistic properties of maintaining elbow stability. Conclusion: Detailed analysis of fibers of the MUCL allows for further understanding of its kinematic function. This study provides MUCL group coverage area and kinematic function for each degree of motion arc, allowing selective reconstruction of the MUCL according to mechanism of injury. Clinical Relevance: Understanding the dominant functional fibers of the MUCL will benefit surgeons attempting MUCL reconstruction and will enhance further anatomic study.

APA, Harvard, Vancouver, ISO, and other styles

9

Streng, Martha L., Laurentiu S. Popa, and Timothy J. Ebner. "Climbing fibers predict movement kinematics and performance errors." Journal of Neurophysiology 118, no. 3 (September 1, 2017): 1888–902. http://dx.doi.org/10.1152/jn.00266.2017.

Full text

Abstract:

Requisite for understanding cerebellar function is a complete characterization of the signals provided by complex spike (CS) discharge of Purkinje cells, the output neurons of the cerebellar cortex. Numerous studies have provided insights into CS function, with the most predominant view being that they are evoked by error events. However, several reports suggest that CSs encode other aspects of movements and do not always respond to errors or unexpected perturbations. Here, we evaluated CS firing during a pseudo-random manual tracking task in the monkey ( Macaca mulatta). This task provides extensive coverage of the work space and relative independence of movement parameters, delivering a robust data set to assess the signals that activate climbing fibers. Using reverse correlation, we determined feedforward and feedback CSs firing probability maps with position, velocity, and acceleration, as well as position error, a measure of tracking performance. The direction and magnitude of the CS modulation were quantified using linear regression analysis. The major findings are that CSs significantly encode all three kinematic parameters and position error, with acceleration modulation particularly common. The modulation is not related to “events,” either for position error or kinematics. Instead, CSs are spatially tuned and provide a linear representation of each parameter evaluated. The CS modulation is largely predictive. Similar analyses show that the simple spike firing is modulated by the same parameters as the CSs. Therefore, CSs carry a broader array of signals than previously described and argue for climbing fiber input having a prominent role in online motor control. NEW & NOTEWORTHY This article demonstrates that complex spike (CS) discharge of cerebellar Purkinje cells encodes multiple parameters of movement, including motor errors and kinematics. The CS firing is not driven by error or kinematic events; instead it provides a linear representation of each parameter. In contrast with the view that CSs carry feedback signals, the CSs are predominantly predictive of upcoming position errors and kinematics. Therefore, climbing fibers carry multiple and predictive signals for online motor control.

APA, Harvard, Vancouver, ISO, and other styles

10

Skulborstad, A. J., Y. Wang, J. D. Davidson, S. M. Swartz, and N. C. Goulbourne. "Polarized Image Correlation for Large Deformation Fiber Kinematics." Experimental Mechanics 53, no. 8 (May 3, 2013): 1405–13. http://dx.doi.org/10.1007/s11340-013-9751-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Smith, Andrew W. "A Biomechanical Analysis of Amputee Athlete Gait." International Journal of Sport Biomechanics 6, no. 3 (August 1990): 262–82. http://dx.doi.org/10.1123/ijsb.6.3.262.

Full text

Abstract:

The aims of the present study were to quantify lower limb kinetics and kinematics during walking and slow jogging of below-knee amputee athletes and to demonstrate the usefulness of the additional information provided by kinetic analyses as compared to that of kinematic assessments alone. Kinematic and force platform data from three amputee subjects were collected while the subjects walked and jogged in the laboratory. Results indicated that neither prosthesis (SACH and an energy-storing carbon fiber or ESCF) emulated the kinetics or the kinematics of so-called normal gait during walking. While the knee joint on the prosthetic side clearly tended to be biased toward extension during stance, the knee flexors were dominant and acted concentrically during this phase of the gait cycle. An examination of prosthetic limb hip and knee joint kinetics at both cadences revealed the functional role played by the hamstrings early in stance. The results indicated that with increasing cadence, less variability, measured by coefficients of variation, was evident in the kinematic data while the opposite was true for the kinetics.

APA, Harvard, Vancouver, ISO, and other styles

12

Kim, Chun IL. "Superposed Incremental Deformations of an Elastic Solid Reinforced with Fibers Resistant to Extension and Flexure." Advances in Materials Science and Engineering 2018 (December 13, 2018): 1–11. http://dx.doi.org/10.1155/2018/6501985.

Full text

Abstract:

A comprehensive linear model for an elastic solid reinforced with fibers resistant to extension and flexure is presented. This includes the analysis of both unidirectional and bidirectional fiber-reinforced composites subjected to in-plane deformations. Within the prescription of the superposed incremental deformations, the fiber kinematics are approximated and used to determine the Euler equilibrium equations. The constraints of bulk incompressibility and admissible boundary conditions are also discussed for completeness. In particular, the complete systems of differential equations are obtained for the cases of Neo-Hookean and Mooney–Rivlin types of materials from which analytical solutions can be obtained.

APA, Harvard, Vancouver, ISO, and other styles

13

Greschik, G., K. C. Park, and M. Natori. "Helically Curved Unfurlable Structural Elements: Kinematic Analysis and Laboratory Demonstration." Journal of Mechanical Design 118, no. 1 (March 1, 1996): 22–28. http://dx.doi.org/10.1115/1.2826852.

Full text

Abstract:

The concept of the unfurling deployment of helically curved tubular members is proposed and its feasibility is confirmed through kinematic analyses and a demonstration model. The challenge of curved geometry—the varying lengths of longitudinal fiber lines across the member’s constituent strip—is answered by a noncylindrical storage drum shaped not to engender membrane strains in the retracted configuration (for a membrane strain-free unfurled state). The overall kinematics and the involved strains are numerically investigated and the feasibility of the deployment process itself is confirmed via a beryllium copper model.

APA, Harvard, Vancouver, ISO, and other styles

14

Mezher, Rabih, Jack Arayro, Nicolas Hascoet, and Francisco Chinesta. "Study of Concentrated Short Fiber Suspensions in Flows, Using Topological Data Analysis." Entropy 23, no. 9 (September 18, 2021): 1229. http://dx.doi.org/10.3390/e23091229.

Full text

Abstract:

The present study addresses the discrete simulation of the flow of concentrated suspensions encountered in the forming processes involving reinforced polymers, and more particularly the statistical characterization and description of the effects of the intense fiber interaction, occurring during the development of the flow induced orientation, on the fibers’ geometrical center trajectory. The number of interactions as well as the interaction intensity will depend on the fiber volume fraction and the applied shear, which should affect the stochastic trajectory. Topological data analysis (TDA) will be applied on the geometrical center trajectories of the simulated fiber to prove that a characteristic pattern can be extracted depending on the flow conditions (concentration and shear rate). This work proves that TDA allows capturing and extracting from the so-called persistence image, a pattern that characterizes the dependence of the fiber trajectory on the flow kinematics and the suspension concentration. Such a pattern could be used for classification and modeling purposes, in rheology or during processing monitoring.

APA, Harvard, Vancouver, ISO, and other styles

15

Vonk, N. H., N. A. M. Verschuur, R. H. J. Peerlings, M. G. D. Geers, and J. P. M. Hoefnagels. "Robust and precise identification of the hygro-expansion of single fibers: a full-field fiber topography correlation approach." Cellulose 27, no. 12 (May 27, 2020): 6777–92. http://dx.doi.org/10.1007/s10570-020-03180-z.

Full text

Abstract:

Abstract Over the past decades, natural fibers have become an important constituent in multiple engineering- and biomaterials. Their high specific strength, biodegradability, low-cost production, recycle-ability, vast availability and easy processing make them interesting for many applications. However, fiber swelling due to moisture uptake poses a key challenge, as it significantly affects the geometric stability and mechanical properties. To characterize the hygro-mechanical behavior of fibers in detail, a novel micromechanical characterization method is proposed which allows continuous full-field fiber surface displacement measurements during wetting and drying. A single fiber is tested under an optical height microscope inside a climate chamber wherein the relative humidity is changed to capture the fiber swelling behavior. These fiber topographies are, subsequently, analyzed with an advanced Global Digital Height Correlation methodology dedicated to extract the full three-dimensional fiber surface displacement field. The proposed method is validated on four different fibers: flat viscose, trilobal viscose, 3D-printed hydrogel and eucalyptus, each having different challenges regarding their geometrical and hygroscopic properties. It is demonstrated that the proposed method is highly robust in capturing the full-field fiber kinematics. A precision analysis shows that, for eucalyptus, at 90% relative humidity, an absolute surface strain precision in the longitudinal and transverse directions of, respectively, 1.2 × 10-4 and 7 × 10-4 is achieved, which is significantly better than existing techniques in the literature. The maximum absolute precision in both directions for the other three tested fibers is even better, demonstrating that this method is versatile for precise measurements of the hygro-expansion of a wide range of fibers. Graphic abstract

APA, Harvard, Vancouver, ISO, and other styles

16

Ansari, Farhad, and Rajendra K. Navalurkar. "Kinematics of Crack Formation in Cementitious Composites by Fiber Optics." Journal of Engineering Mechanics 119, no. 5 (May 1993): 1048–61. http://dx.doi.org/10.1061/(asce)0733-9399(1993)119:5(1048).

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Criscione, J. C., and W. C. Hunter. "Kinematics and elasticity framework for materials with two fiber families." Continuum Mechanics and Thermodynamics 15, no. 6 (November 1, 2003): 613–28. http://dx.doi.org/10.1007/s00161-003-0138-0.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Quinn, Kyle P., and Beth A. Winkelstein. "Altered collagen fiber kinematics define the onset of localized ligament damage during loading." Journal of Applied Physiology 105, no. 6 (December 2008): 1881–88. http://dx.doi.org/10.1152/japplphysiol.90792.2008.

Full text

Abstract:

Detecting the initiation of mechanical injury to biological tissue, and not just its ultimate failure, is critical to a sensitive and specific characterization of tissue tolerance, development of quantitative relationships between macro- and microstructural tissue responses, and appropriate interpretation of physiological responses to loading. We have developed a novel methodological approach to detect the onset and spatial location of structural damage in collagenous soft tissue, before its visible rupture, via identification of atypical regional collagen fiber kinematics during loading. Our methods utilize high-speed quantitative polarized light imaging to identify the onset of tissue damage in ligament regions where mean collagen fiber rotation significantly deviates from its behavior during noninjurious loading. This technique was validated by its ability to predict the location of visible rupture ( P = 0.0009). This fiber rotation-based metric of damage identifies potential facet capsular ligament injury beginning well before rupture, at 51 ± 12% of the displacement required to produce tissue failure. Although traditional macroscale strain metrics fail to identify the location of microstructural damage, initial injury detection determined by altered fiber rotation was significantly correlated ( R = 0.757, P = 0.049) with tissue yield (defined by a decrease in stiffness), supporting the capabilities of this method. Damaged regions exhibited higher variance in fiber direction than undamaged regions ( P = 0.0412).

APA, Harvard, Vancouver, ISO, and other styles

19

Ledderose, Lukas, Abtin Baghdadi, and Harald Kloft. "Magnetic Alignment of Microsteel Fibers as Strategy for Reinforcing UHPFRC." Open Conference Proceedings 1 (February 15, 2022): 99–114. http://dx.doi.org/10.52825/ocp.v1i.79.

Full text

Abstract:

The objective of this paper is to provide an insight into current basic research at ITE on the manufacturing process of resource-efficient components through the controlled, automated magnetic distribution and alignment of steel fibers in UHPFRC (Ultra-High Performance Fibre-Reinforced Concrete). The method for distributing and aligning steel fibers in UHPFRC is based on the physical phenomenon of magnetism. Since steel fibers are ferromagnetic, magnetic fields can selectively change their position in the fresh concrete and align them according to the force flow and the maxim "form follows force". The magnetic fiber alignment (MFA) process developed on this principle combines the capabilities of digital and automized component manufacturing with the potential of targeted fiber alignment to increase the material efficiency of UHPFRC. It is highlighted at four levels: UHPFRC At the material level, studies were conducted on the composite properties of different brand-new and recycled microsteel fibers (MSF), formwork designs suitable for the MFA process were developed, flux densities of different magnets were simulated with special software solutions and measured in practice, and an end effector was fabricated that was implemented on 3- and 6-axis kinematics. At the process level, the interaction of the main parameters of the MFA process was evaluated by visual analysis on transparent glucose syrup-based solutions, and series of specimens were analyzed by micro-CT scans. At the component level, centric tensile tests were performed on a wide variation of dog-bones to provide an assessment of the potential increase in tensile performance of UHPFRC by the MFA process. At an economic and environmental evaluation level, the results from the tensile tests were used to assess and quantify the potential savings from reducing the fiber content and using recycled steel fibers.

APA, Harvard, Vancouver, ISO, and other styles

20

Li, Ling, Yun Jiang Miao, Zhong Bin Wang, and Xiong Bing Li. "Kinematics Modeling on CFRP Curved Part Ultrasonic Test." Advanced Materials Research 186 (January 2011): 136–40. http://dx.doi.org/10.4028/www.scientific.net/amr.186.136.

Full text

Abstract:

Aimed at inner flaw in CFRP（carbon fiber reinforced plastic）curved part, build the ultrasonic test technological process. Based on five-freedom CFRP curved part robot, the mechanics structure model is set up. And then, by basic principle of robot kinematics, the kinematics equation of five-freedom ultrasonic test system is derived. Finally, through solving the direct root and converse root, the mathematics relation expression between the movement variable of servo motors and ultrasonic probe coordinate is obtained.

APA, Harvard, Vancouver, ISO, and other styles

21

Hu, Xintong, Lingling Yao, Yujing Zhang, Zhuo Meng, and Yize Sun. "Optimizing structural parameters of carbon fiber braiding carriers based on antlion optimization algorithm." Journal of Industrial Textiles 50, no. 4 (February 27, 2019): 460–82. http://dx.doi.org/10.1177/1528083719831085.

Full text

Abstract:

Braiding carriers, which are the important parts of a braiding machine, have the functions such as carrying braiding materials, controlling tension of carbon fiber, and driving carbon fiber movement. During the braiding process, two groups of carbon fibers braided in clockwise and counter clockwise direction contact each other and form relative motion, which causes friction and fuzzing. In order to improve this situation, the structural parameters of the carriers need to be optimized. In this paper, the kinematics and dynamics models were established based on the structure of braiding carriers. The micro-element method was used to analyze the relationship between the fiber length released from the yarn barrel, the rotation angle of the lever, and the tension of the carbon fiber. To limit the fluctuant range of carbon fiber tension, and to alleviate the fluffing phenomenon caused by the two groups of carbon fiber in contact with each other, antlion algorithm was used to optimize the structural parameters of braiding carriers. The simulation results showed that the tension of the carbon fiber can meet the processing requirements by adjusting the starting angle of each stage of carrier, the length of lever, the elastic coefficient of springs, and pre-compression of springs. It can be known that the structural parameters of braiding carriers optimized by antlion algorithm could meet the requirement of carbon fiber tension.

APA, Harvard, Vancouver, ISO, and other styles

22

Mondoringin, Mielke R. I. A. J., and Masayasu Ohtsu. "Kinematics on Split-Tensile Test of Fiber-Reinforced Concrete by AE." Journal of Advanced Concrete Technology 11, no. 8 (August 28, 2013): 196–205. http://dx.doi.org/10.3151/jact.11.196.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

van den Bogert, A. J., C. N. Maganaris, and M. F. Bobbert. "All you need is work: Muscle function predicted from fiber kinematics." Journal of Biomechanics 39 (January 2006): S56. http://dx.doi.org/10.1016/s0021-9290(06)83106-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Morin, Claire, Stéphane Avril, and Christian Hellmich. "Non‐affine fiber kinematics in arterial mechanics: a continuum micromechanical investigation." ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik 98, no. 12 (October 2, 2018): 2101–21. http://dx.doi.org/10.1002/zamm.201700360.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Caldwell, Graham E. "Tendon Elasticity and Relative Length: Effects on the Hill Two-Component Muscle Model." Journal of Applied Biomechanics 11, no. 1 (February 1995): 1–24. http://dx.doi.org/10.1123/jab.11.1.1.

Full text

Abstract:

The effects of relative tendon/fiber proportion and tendon elasticity on the force output of the Hill muscle model (a contractile component [CC] in series with an elastic element [SEC]) were examined through computer simulation. Three versions of the Hill model were constructed. Model 1 examined the effect of relative tendon/fiber proportion on CC kinematics and kinetics during an isometric twitch, while Model 2 compared the effect of changes in tendon compliance. These models revealed force profile differences related to alterations in CC velocity, although the reasons underlying the variation in CC kinematics were different. The relative tendon/fiber proportion and tendon compliance differences were examined in combination in Model 3. Test simulations revealed response differences among the three model versions, and therefore verified Alexander and Ker's (1990) contention that the morphology of muscle is related to design criteria. It is suggested that the implementation of generalized muscle models to represent specific units of the musculoskeletal system should be done carefully and that the implementation process itself warrants further study.

APA, Harvard, Vancouver, ISO, and other styles

26

Akbaş, Şeref, Hakan Ersoy, Bekir Akgöz, and Ömer Civalek. "Dynamic Analysis of a Fiber-Reinforced Composite Beam under a Moving Load by the Ritz Method." Mathematics 9, no. 9 (May 6, 2021): 1048. http://dx.doi.org/10.3390/math9091048.

Full text

Abstract:

This paper presents the dynamic responses of a fiber-reinforced composite beam under a moving load. The Timoshenko beam theory was employed to analyze the kinematics of the composite beam. The constitutive equations for motion were obtained by utilizing the Lagrange procedure. The Ritz method with polynomial functions was employed to solve the resulting equations in conjunction with the Newmark average acceleration method (NAAM). The influence of fiber orientation angle, volume fraction, and velocity of the moving load on the dynamic responses of the fiber-reinforced nonhomogeneous beam is presented and discussed.

APA, Harvard, Vancouver, ISO, and other styles

27

Yang, Kai, Jian Cheng Yang, Jian Feng Qin, Hua Qing Wang, Yu Bai, Shuang Hu Hu, and Xiu Ming Jiang. "The Kinematics Simulation and Analysis of the Multilayer Carbon Fiber Loom's Beating-Up Mechanism in ADAMS." Advanced Materials Research 846-847 (November 2013): 52–55. http://dx.doi.org/10.4028/www.scientific.net/amr.846-847.52.

Full text

Abstract:

This article designs a new set of beating-up mechanism for the multilayer angle interlocking construction loom based on the requirements of special material of carbon fiber and weaving technology,and it can battening 30 layers carbon fiber at a beating-up.Through building the 3D solid models for linkage mechanism in SolidWorks, it show that the beating-up mechanism Run smoothly by the kinematics and dynamics analysis of different beating-up rule in ADAMS.

APA, Harvard, Vancouver, ISO, and other styles

28

Fares, N., and G. J. Dvorak. "Finite Deformation Constitutive Relations for Elastic-Plastic Fibrous Metal Matrix Composites." Journal of Applied Mechanics 60, no. 3 (September 1, 1993): 619–25. http://dx.doi.org/10.1115/1.2900849.

Full text

Abstract:

This paper presents a finite strain formulation of a plasticity theory of fibrous composite materials. An additive decomposition is adopted to describe the kinematics of large deformations; a lattice is defined by the current fiber direction. Elastic and plastic constitutive relations are developed from the proposition that distortions take place relative to the fiber direction. A numerical method is proposed for integrating the constitutive equations. Finally, an illustrative example of the formulation indicates that when axial loads along the fiber direction are comparable to the instantaneous shear stiffness, the finite deformation formulation is needed even with small strains.

APA, Harvard, Vancouver, ISO, and other styles

29

Stella, John A., William R. Wagner, and Michael S. Sacks. "Scale-dependent fiber kinematics of elastomeric electrospun scaffolds for soft tissue engineering." Journal of Biomedical Materials Research Part A 9999A (2009): NA. http://dx.doi.org/10.1002/jbm.a.32593.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Altan, M. Cengiz. "A Review of Fiber-Reinforced Injection Molding: Flow Kinematics and Particle Orientation." Journal of Thermoplastic Composite Materials 3, no. 4 (October 1990): 275–313. http://dx.doi.org/10.1177/089270579000300402.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Chiba, Kunji, and Francisco Chinesta. "Numerical simulation of flow kinematics and fiber orientation for multi-disperse suspension." Rheologica Acta 45, no. 1 (July 2, 2005): 1–13. http://dx.doi.org/10.1007/s00397-004-0431-2.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Shahab, Shima, and Alper Erturk. "Coupling of experimentally validated electroelastic dynamics and mixing rules formulation for macro-fiber composite piezoelectric structures." Journal of Intelligent Material Systems and Structures 28, no. 12 (November 3, 2016): 1575–88. http://dx.doi.org/10.1177/1045389x16672732.

Full text

Abstract:

Piezoelectric structures have been used in a variety of applications ranging from vibration control and sensing to morphing and energy harvesting. In order to employ the effective 33-mode of piezoelectricity, interdigitated electrodes have been used in the design of macro-fiber composites which employ piezoelectric fibers with rectangular cross section. In this article, we present an investigation of the two-way electroelastic coupling (in the sense of direct and converse piezoelectric effects) in bimorph cantilevers that employ interdigitated electrodes for 33-mode operation. A distributed-parameter electroelastic modeling framework is developed for the elastodynamic scenarios of piezoelectric power generation and dynamic actuation. Mixing rules (i.e. rule of mixtures) formulation is employed to evaluate the equivalent and homogenized properties of macro-fiber composite structures. The electroelastic and dielectric properties of a representative volume element (piezoelectric fiber and epoxy matrix) between two neighboring interdigitated electrodes are then coupled with the global electro-elastodynamics based on the Euler–Bernoulli kinematics accounting for two-way electromechanical coupling. Various macro-fiber composite bimorph cantilevers with different widths are tested for resonant dynamic actuation and power generation with resistive shunt damping. Excellent agreement is reported between the measured electroelastic frequency response and predictions of the analytical framework that bridges the continuum electro-elastodynamics and mixing rules formulation.

APA, Harvard, Vancouver, ISO, and other styles

33

Yang, Kai, Jian Cheng Yang, Hua Qing Wang, Jian Feng Qin, Yu Bai, Shuang Hu Hu, and Xiu Ming Jiang. "Research of the Multilayer Carbon Fiber Loom's Shedding Device." Advanced Materials Research 846-847 (November 2013): 48–51. http://dx.doi.org/10.4028/www.scientific.net/amr.846-847.48.

Full text

Abstract:

This paper designs a set of jacquard and dobby shedding device, it specially suitable for 30 layers carbon fiber weaving equipment, which meet the requirement of the special shed. Through to the main drive system design of the jacquard, the structural design and the kinematics analysis of tandem cylinder dobby shedding mechanism, so that the design reasonable. The experiments show that the opening device can well ensure the shedding action orderly, continuously and the shed clear, it can meet the requirements.

APA, Harvard, Vancouver, ISO, and other styles

34

Xu, Shuang, Alessandro Ferraris, Andrea Giancarlo Airale, and Massimiliana Carello. "Elasto-kinematics design of an innovative composite material suspension system." Mechanical Sciences 8, no. 1 (February 24, 2017): 11–22. http://dx.doi.org/10.5194/ms-8-11-2017.

Full text

Abstract:

Abstract. In this paper, a lightweight suspension system for small urban personal transportation vehicle is presented. A CFRP (Carbon fiber reinforce polymer) beam spring has been used to efficiently integrate the functions of suspension control arm and anti-roll bar. Composites materials were chosen to tailor the required behavior of the beam spring and to reduce the weight. Furthermore, larger space for engine compartment has been provided thanks to the compact arrangement of beam suspension components. This suspension could be installed on electric/hybrid vehicles and conventional automobiles.

APA, Harvard, Vancouver, ISO, and other styles

35

Seyed Bolouri, Seyed Ehsan, Chun IL Kim, and Seunghwa Yang. "Linear theory for the mechanics of third-gradient continua reinforced with fibers resistance to flexure." Mathematics and Mechanics of Solids 25, no. 4 (December 16, 2019): 937–60. http://dx.doi.org/10.1177/1081286519893408.

Full text

Abstract:

A linear model, framed in the setting of the second strain gradient theory, is presented for the mechanics of an elastic solid reinforced with fibers resistant to flexure. The kinematics and bending resistance of the fibers are formulated via the second and third gradient of the continuum deformation. The corresponding Euler equations and admissible boundary conditions are then obtained by means of iterated integration by parts and variational principles arising in the third gradient of virtual displacement. In particular, within the prescription of superposed incremental deformations, we derive a compatible linear model from which a complete analytical solution describing the deformations of fiber composites is obtained. The proposed linear model predicts smooth and dilatational shear angle distributions over the domain of interest, which are also aligned with the results obtained from the corresponding nonlinear theory.

APA, Harvard, Vancouver, ISO, and other styles

36

Xinfeng, Ge, and Li Ruihua. "Study of Automatic Fiber Placement Manipulator's Robotic Kinematics Manipulability Based on Volume Element." Research Journal of Applied Sciences, Engineering and Technology ` 11, no. 9 (February 21, 2013): 2221–24. http://dx.doi.org/10.19026/rjaset.5.4775.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Billiar, K. L., and M. S. Sacks. "A method to quantify the fiber kinematics of planar tissues under biaxial stretch." Journal of Biomechanics 30, no. 7 (July 1997): 753–56. http://dx.doi.org/10.1016/s0021-9290(97)00019-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Spagnuolo, Mario, M. Erden Yildizdag, Xavier Pinelli, Antonio Cazzani, and François Hild. "Out-of-plane deformation reduction via inelastic hinges in fibrous metamaterials and simplified damage approach." Mathematics and Mechanics of Solids 27, no. 6 (November 17, 2021): 1011–31. http://dx.doi.org/10.1177/10812865211052670.

Full text

Abstract:

The mechanical behavior of fibrous metamaterials is mainly determined by the interactions between the fibers composing the architecture. These interactions are usually of two different kinds: those directly depending on the positions of the fibers and those that need mediators, usually consisting of hinges, either inelastic or perfect, inducing restrictions on the kinematics of the fiber joints. In cases of interest, it has been observed that hinges can either have a certain torsional stiffness or behave as perfect joints, simply ensuring that the fibers remain interconnected, but not applying any constraint on the relative rotations between them. Here the effect of torsional stiffness of inelastic hinges is studied in two shear tests for a selected fibrous metamaterial. It is shown that the stiffness of hinges can be tailored to avoid, or at least reduce, out-of-plane deformations. Moreover, it is shown that, after reaching a threshold, permanent deformations are observed. This phenomenon is treated in a simplified way, by introducing damage in the continuum model.

APA, Harvard, Vancouver, ISO, and other styles

39

Lake, Spencer P., Daniel H. Cortes, Jennifer A. Kadlowec, Louis J. Soslowsky, and Dawn M. Elliott. "Evaluation of affine fiber kinematics in human supraspinatus tendon using quantitative projection plot analysis." Biomechanics and Modeling in Mechanobiology 11, no. 1-2 (April 3, 2011): 197–205. http://dx.doi.org/10.1007/s10237-011-0303-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Lu, Hua, Fan Yang, Hong Yu Jin, and Zhen Yu Han. "A Post-Processing Algorithm for Gantry-Type Automated Fiber Placement Machine." Advanced Materials Research 763 (September 2013): 187–90. http://dx.doi.org/10.4028/www.scientific.net/amr.763.187.

Full text

Abstract:

Automated fiber placement (AFP) is a recent development of composite manufacturing technology and is widely used in the field of aerospace. The post processing of AFP has an important influence to the stability of machine movement and the manufacturing accuracy. This paper presents a post processing algorithm of a kind of 7-DOF gantry-type automated fiber placement equipment. The linking coordinates are set up according to the structure of the machine. To solve the redundant degree problem, pose separation method is adopted to calculate the inverse kinematics of the spindle rotation DOF and the other six movement DOFs of the manipulator respectively. Finally, reasonable parameters of each motion of the machine are obtained by the proposed post-processing method.

APA, Harvard, Vancouver, ISO, and other styles

41

Usal, Melek. "On Continuum Damage Modeling of Fiber Reinforced Viscoelastic Composites with Microcracks in terms of Invariants." Mathematical Problems in Engineering 2015 (2015): 1–15. http://dx.doi.org/10.1155/2015/624750.

Full text

Abstract:

A continuum damage model is developed for the linear viscoelastic behavior of composites with microcracks consisting of an isotropic matrix reinforced by two arbitrarily independent and inextensible fiber families. Despite the fact that the matrix material is isotropic, the model in consideration bears the characteristic of directed media included in the transverse isotropy symmetry group solely due to its fibers distributions and the existence of microcracks. Using the basic laws of continuum damage mechanics and equations belonging to kinematics and deformation geometries of fibers, the constitutive functions have been obtained. It has been detected as a result of the thermodynamic constraints that the stress potential function is dependent on two symmetric tensors and two vectors, whereas the dissipative stress function is dependent on four symmetric tensors and two vectors. To determine arguments of the constitutive functionals, findings relating to the theory of invariants have been used as a method because of the fact that isotropy constraint is imposed on the material. As a result the linear constitutive equations of elastic stress, dissipative stress, and strain energy density release rate have been written in terms of material coordinate description. Using these expressions, total stress has been found.

APA, Harvard, Vancouver, ISO, and other styles

42

Usal, Melek. "A Constitutive Formulation for the Linear Thermoelastic Behavior of Arbitrary Fiber-Reinforced Composites." Mathematical Problems in Engineering 2010 (2010): 1–19. http://dx.doi.org/10.1155/2010/404398.

Full text

Abstract:

The linear thermoelastic behavior of a composite material reinforced by two independent and inextensible fiber families has been analyzed theoretically. The composite material is assumed to be anisotropic, compressible, dependent on temperature gradient, and showing linear elastic behavior. Basic principles and axioms of modern continuum mechanics and equations belonging to kinematics and deformation geometries of fibers have provided guidance and have been determining in the process of this study. The matrix material is supposed to be made of elastic material involving an artificial anisotropy due to fibers reinforcing by arbitrary distributions. As a result of thermodynamic constraints, it has been determined that the free energy function is dependent on a symmetric tensor and two vectors whereas the heat flux vector function is dependent on a symmetric tensor and three vectors. The free energy and heat flux vector functions have been represented by a power series expansion, and the type and the number of terms taken into consideration in this series expansion have determined the linearity of the medium. The linear constitutive equations of the stress and heat flux vector are substituted in the Cauchy equation of motion and in the equation of conservation of energy to obtain the field equations.

APA, Harvard, Vancouver, ISO, and other styles

43

Deriglazov, A. A. "Kinematics of semiclassical spin and spin fiber bundle associated with so(n) Lie-Poisson manifold." Journal of Physics: Conference Series 411 (January 28, 2013): 012011. http://dx.doi.org/10.1088/1742-6596/411/1/012011.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Higham, Timothy E., Kathryn R. Lipsett, Douglas A. Syme, and Anthony P. Russell. "Controlled Chaos: Three-Dimensional Kinematics, Fiber Histochemistry, and Muscle Contractile Dynamics of Autotomized Lizard Tails." Physiological and Biochemical Zoology 86, no. 6 (November 2013): 611–30. http://dx.doi.org/10.1086/673546.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Robbins, D. H., and J. N. Reddy. "Adaptive Hierarchical Kinematics in Modeling Progressive Damage and Global Failure in Fiber-reinforced Composite Laminates." Journal of Composite Materials 42, no. 2 (January 2008): 143–72. http://dx.doi.org/10.1177/0021998307086210.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Lee, Chung-Hao, Will Zhang, Jun Liao, Christopher A. Carruthers, Jacob I. Sacks, and Michael S. Sacks. "On the Presence of Affine Fibril and Fiber Kinematics in the Mitral Valve Anterior Leaflet." Biophysical Journal 108, no. 8 (April 2015): 2074–87. http://dx.doi.org/10.1016/j.bpj.2015.03.019.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Chinesta, Francisco, and Arnaud Poitou. "Numerical Analysis of the Coupling Between the Flow Kinematics and the Fiber Orientation in Eulerian Simulations of Dilute Short Fiber Suspensions Flows." Canadian Journal of Chemical Engineering 80, no. 6 (December 2002): 1107–14. http://dx.doi.org/10.1002/cjce.5450800612.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Blankevoort, L., R. Huiskes, and A. de Lange. "Recruitment of Knee Joint Ligaments." Journal of Biomechanical Engineering 113, no. 1 (February 1, 1991): 94–103. http://dx.doi.org/10.1115/1.2894090.

Full text

Abstract:

On the basis of earlier reported data on the in vitro kinematics of passive knee-joint motions of four knee specimens, the length changes of ligament fiber bundles were determined by using the points of insertion on the tibia and femur. The kinematic data and the insertions of the ligaments were obtained by using Roentgenstereophotogrammetry. Different fiber bundles of the anterior and posterior cruciate ligaments and the medial and lateral collateral ligaments were identified. On the basis of an assumption for the maximal strain of each ligament fiber bundle during the experiments, the minimal recruitment length and the probability of recruitment were defined and determined. The motions covered the range from extension to 95 degrees flexion and the loading conditions included internal or external moments of 3 Nm and anterior or posterior forces of 30N. The ligament length and recruitment patterns were found to be consistent for some ligament bundles and less consistent for other ligament bundles. The most posterior bundle of each ligament was recruited in extension and the lower flexion angles, whereas the anterior bundle was recruited for the higher flexion angles. External rotation generally recruited the collateral ligaments, while internal rotation recruited the cruciate ligaments. However, the anterior bundle of the posterior cruciate ligament was recruited with external rotation at the higher flexion angles. At the lower flexion angles, the anterior cruciate and the lateral collateral ligaments were recruited with an anterior force. The recruitment of the posterior cruciate ligament with a posterior force showed that neither its most anterior nor its most posterior bundle was recruited at the lower flexion angles. Hence, the posterior restraint must have been provided by the intermediate fiber bundles, which were not considered in the experiment. At the higher flexion angles, the anterior bundles of the anterior cruciate ligament and the posterior cruciate ligament were found to be recruited with anterior and posterior forces, respectively. The minimal recruitment length and the recruitment probability of ligament fiber bundles are useful parameters for the evaluation of ligament length changes in those experiments where no other method can be used to determine the zero strain lengths, ligament strains and tensions.

APA, Harvard, Vancouver, ISO, and other styles

49

Lantsoght, Eva. "Database of Shear Experiments on Steel Fiber Reinforced Concrete Beams without Stirrups." Materials 12, no. 6 (March 19, 2019): 917. http://dx.doi.org/10.3390/ma12060917.

Full text

Abstract:

Adding steel fibers to concrete improves the capacity in tension-driven failure modes. An example is the shear capacity in steel fiber reinforced concrete (SFRC) beams with longitudinal reinforcement and without shear reinforcement. Since no mechanical models exist that can fully describe the behavior of SFRC beams without shear reinforcement failing in shear, a number of empirical equations have been suggested in the past. This paper compiles the existing empirical equations and code provisions for the prediction of the shear capacity of SFRC beams failing in shear as well as a database of 488 experiments reported in the literature. The experimental shear capacities from the database are then compared to the prediction equations. This comparison shows a large scatter on the ratio of experimental to predicted values. The practice of defining the tensile strength of SFRC based on different experiments internationally makes the comparison difficult. For design purposes, the code prediction methods based on the Eurocode shear expression provide reasonable results (with coefficients of variation on the ratio tested/predicted shear capacities of 27–29%). None of the currently available methods properly describe the behavior of SFRC beams failing in shear. As such, this work shows the need for studies that address the different shear-carrying mechanisms in SFRC and its crack kinematics.

APA, Harvard, Vancouver, ISO, and other styles

50

Vakiel, Paris, Mehdi Shekarforoush, Christopher R. Dennison, Michael Scott, Cyril B. Frank, David A. Hart, and Nigel G. Shrive. "Stress Measurements on the Articular Cartilage Surface Using Fiber Optic Technology and In-Vivo Gait Kinematics." Annals of Biomedical Engineering 48, no. 12 (April 27, 2020): 2836–45. http://dx.doi.org/10.1007/s10439-020-02516-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

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!