These metrics – along with calibration data on the size and stiffnesses of objects of different material types – is what gives the gripper a sense of what material the object is made of.
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Several factors affect these stiffnesses to varying degrees. These include wheel radius, rim bending and torsional stiffness, number of spokes, spoke gauge, lacing pattern, hub stiffness, hub flange spacing, hub radius. In general lateral and radial stiffness decreases with the number of spoke crossings and torsional stiffness increases with the number of spoke crossings. One factor that has little influence on these stiffnesses is spoke tension.
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For example, a point on a horizontal beam can undergo both a vertical displacement and a rotation relative to its undeformed axis. When there are M degrees of freedom a M x M matrix must be used to describe the stiffness at the point. The diagonal terms in the matrix are the direct-related stiffnesses (or simply stiffnesses) along the same degree of freedom and the off-diagonal terms are the coupling stiffnesses between two different degrees of freedom (either at the same or different points) or the same degree of freedom at two different points. In industry, the term influence coefficient is sometimes used to refer to the coupling stiffness.
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From these ground reaction forces centre of gravity related physical parameters like relative maximum forces, velocity, power output, kinetic energy, potential energy, height of jump or whole body stiffnessFarley CT, Houdijk HH, Van Strien C, Louie M: Mechanism of leg stiffness adjustment for hopping on surfaces of different stiffnesses, Mechanism of leg stiffness adjustment for hopping on surfaces of different stiffnesses, are calculated. If the ground reaction forces are measured separately for left and right leg in addition body imbalances during the motions can be analysed. This enables for example to document the results of therapy.Fricke O, Witzel C, Schickendantz S, Sreeram N, Brockmeier K, Schoenau E: Mechanographic characteristics of adolescents and young adults with congenital heart disease, Eur J Pediatr.
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However, in lightly loaded bearings, such as disk drives, the typical ball bearing stiffnesses are ~10^7 MN/m. Comparable fluid bearings have stiffness of ~10^6 MN/m. Because of this, some fluid bearings, particularly hydrostatic bearings, are deliberately designed to pre-load the bearing to increase the stiffness. Fluid bearings often inherently add significant damping.
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Long wheelbase and trail and a flat steering-head angle have been found to increase weave-mode damping. Lateral distortion can be countered by locating the front fork torsional axis as low as possible. Cornering weave tendencies are amplified by degraded damping of the rear suspension. Cornering, camber stiffnesses and relaxation length of the rear tire make the largest contribution to weave damping.
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The bending stiffness (EI/L) of a member is represented as the flexural rigidity of the member (product of the modulus of elasticity (E) and the second moment of area (I)) divided by the length (L) of the member. What is needed in the moment distribution method is not the specific values but the ratios of bending stiffnesses between all members.
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Most stiff driver shafts are marked usually X-Stiff or even more. These are commonly professional-level stiffnesses due to the rarity of amateur players capable of hitting swing speeds over 110 mph, although these also occur sometimes. The furthest shooting drivers of all are long-drive-clubs, which may have a 48-inch shaft. This is the maximum legal shaft length in golf.
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Stiffness is typically viewed as a material property describing the amount a material deforms under a given force as described by Hooke's law. This means that objects with higher stiffness are more difficult to bend or deform than objects with lower stiffnesses. This concept can be extended to the limbs and joints of biological organisms in which stiffness describes the degree to which a limb or joint deflects (or bends) under a given load. Limb stiffness can also be described as the static component of impedance.
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Humans change the stiffness of their limbs and joints to adapt to their environment. Limb and joint stiffness has been previously studied and can be quantified in various ways. The basic principle for calculating stiffness is dividing the deformation of a limb by the force applied to the limb, however, there are multiple methods of quantifying limb and joint stiffness with various pros and cons. When quantifying limb stiffness, one cannot simply sum the individual joint stiffnesses due to the nonlinearities of the multi-joint system.
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The human body is able to modulate its limb stiffnesses through various mechanisms with the goal of more effectively interacting with its environment. The body varies the stiffness of its limbs by three primary mechanisms: muscle cocontraction, posture selection, and through stretch reflexes. Muscle cocontraction (similar to muscle tone) is able to vary the stiffness of a joint by the action of antagonistic muscles acting on the joint. The stronger the forces of the antagonistic muscles on the joint are, the stiffer the joint becomes.
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The program calculates the necessary reinforcement, checks the R/C sections capacity, generate interaction failure surfaces, calculates the strains, stresses, curvatures, stiffnesses (II order, creep) and the cracks widths for any reinforced concrete cross - section. The program has reported users in over 30 countries:GaLa Reinforcement official link alashki.com. 2000 Germany, USA, Italy, Belgium, Canada, Netherlands, Spain, Portugal, Sweden, Iceland, UK, South Korea, Greece, Columbia, Bulgaria, Singapore, Saipan, China, Taiwan, Vietnam, El Salvador, Brazil, Ireland, Mexico, Chile, Turkey, New Zealand, France, Haiti, Slovenia, Nicaragua, Philippines, Saudi Arabia, Qatar, Austria, United Arab Emirates.
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Silicon microcantilevers are used for both contact AFM and nc-AFM. Silicon microcantilevers are produced from etching small (~100×10×1 μm) rectangular, triangular, or V-shaped cantilevers from silicon nitride. Originally they were produced without integrated tips and metal tips had to be evaporated on, later a method was found to integrate the tips into the cantilever fabrication process. nc-AFM cantilevers tend to have a higher stiffness, ~40 N/m, and resonant frequency, ~200 kHz, than contact AFM cantilevers (with stiffnesses ~0.2 N/m and resonant frequencies ~15 kHz).
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This confluent layer can be used to study the foreign body response by scrape-injury or depositing electrode microwires on the monolayer, fixing the culture at defined time points after insertion/injury and studying tissue response with histological methods. Another research tool is a numerical model of the mechanical electrode-tissue interface. The goal of this model is not to detail the electrical or chemical characteristics of the interface, but the mechanical ones created by electrode-tissue adhesion, tethering forces, and strain mismatch. This model can be used to predict forces generated at the interface by electrodes of different material stiffnesses or geometries.
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It is noted that for a body with multiple DOF, the equation above generally does not apply since the applied force generates not only the deflection along its own direction (or degree of freedom) but also those along with other directions. For a body with multiple DOF, in order to calculate a particular direct-related stiffness (the diagonal terms), the corresponding DOF is left free while the remaining should be constrained. Under such a condition, the above equation can be used to obtain the direct- related stiffness for the degree of freedom which is unconstrained. The ratios between the reaction forces (or moments) and the produced deflection are the coupling stiffnesses.
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Additionally, YAP is regulated by mechanical cues such as extracellular matrix (ECM) rigidity, strain, shear stress, or adhesive area, processes that are reliant on cytoskeletal integrity. These mechanically induced localization phenomena are thought to be the result of nuclear flattening induced pore size change, mechanosensitive nuclear membrane ion channels, mechanical protein stability, or a variety of other factors. These mechanical factors have also been linked to certain cancer cells via nuclear softening and higher ECM stiffnesses. Under this framework, the nuclear softening phenotype of cancer cells would promote nuclear flattening in response to a force, causing YAP localization, which could explain its over- expression and promoted proliferation in oncogenic cells.
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In particular carbon nanotubes have some of the highest measured tensile stiffnesses and strengths of any material due to the strong covalent sp2 bonds between carbon atoms. However, in order to take advantage of the exceptional mechanical properties of the nanotubes, the load transfer between the nanotubes and matrix must be very large. Like in fiber-reinforced composites, the size dispersion of the carbon nanotubes significantly affects the final properties of the composite. Stress-strain studies of single-walled carbon nanotubes in a polyethylene matrix using molecular dynamics showed that long carbon nanotubes lead to an increase in tensile stiffness and strength due to the large-distance stress transfer and crack propagation prevention.
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An article appearing in a 2008 issue of the Pennsylvania Railroad Technical and Historical Society Magazine showed that inadequate training for engineers transitioning to the T1 may have led to excessive throttle applications, resulting in driver slippage."In Defense of the 5500s", Volume 41, Number 1, Pennsylvania Railroad Technical and Historical Society Magazine, Spring, 2008 Another root cause of wheelslip was faulty "spring equalization": The stiffnesses of the springs supporting the locomotive over the axles were not adjusted to properly equalize the wheel-to-track forces. The drivers were equalized together but not equalized with the engine truck. In the production fleet the PRR equalized the engine truck with the front engine and the trailing truck with the rear engine, which helped to solve the wheelslip problem.
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