Hinge

Abstract: With a rigorous and comprehensive coverage, the second edition of Compliant Mechanisms: Design of Flexure Hinges provides practical answers to the design and analysis of devices that incorporate flexible hinges. Complex-shaped flexible-hinge mechanisms are generated from basic elastic segments by means of a bottom-up compliance (flexibility) approach. The same compliance method and the classical finite element analysis are utilized to study the quasi-static and dynamic performances of these compliant mechanisms. This book offers easy-to-use mathematical tools to investigate a wealth of flexible-hinge configurations and two- or three-dimensional compliant mechanism applications. FEATURES Introduces a bottom-up compliance-based approach to characterize the flexibility of new and existing flexible hinges of straight- and curvilinear-axis configurations Develops a consistent linear lumped-parameter compliance model to thoroughly describe the quasi-static and dynamic behavior of planar/spatial, serial/parallel flexible-hinge mechanisms Utilizes the finite element method to analyze the quasi-statics and dynamics of compliant mechanisms by means of straight- and curvilinear-axis flexible-hinge elements Covers miscellaneous topics such as stress concentration, yielding and related maximum load, precision of rotation of straight- and circular-axis flexible hinges, temperature effects on compliances, layered flexible hinges and piezoelectric actuation/sensing Offers multiple solved examples of flexible hinges and flexible-hinge mechanisms. This book should serve as a reference to students, researchers, academics and anyone interested to investigate precision flexible-hinge mechanisms by linear model-based methods in various areas of mechanical, aerospace or biomedical engineering, as well as in robotics and micro-/nanosystems.

Abstract: A new plastic hinge integration method overcomes the problems with nonobjective response caused by strain-softening behavior in force-based beam-column finite elements. The integration method uses the common concept of a plastic hinge length in a numerically consistent manner. The method, derived from the Gauss-Radau quadrature rule, integrates deformations over specified plastic hinge lengths at the ends of the beam-column element, and it has the desirable property that it reduces to the exact solution for linear problems. Numerical examples show the effect of plastic hinge integration on the response of force-based beam-column elements for both strain-hardening and strain-softening section behavior in the plastic hinge regions. The incorporation of a plastic hinge length in the element integration method ensures objective element and section response, which is important for strain-softening behavior in reinforced concrete structures. Plastic rotations are defined in a consistent manner and clearly related to deformations in the plastic hinges.

Abstract: A folding photo case includes a pair of exterior case members coupled to each other by a first hinge and a pair of interior frame members coupled to respective exterior case members by respective second and third hinges. The first, second and third hinges are preferably torsion bar hinges with the first hinge biasing the exterior case members to an open position and the second and third springs biasing the interior frame members toward interior surfaces of the exterior case members. One or both of the exterior case members are preferably provided with a latch structure which allows the folding case to be latched in a closed position. The dimensions of the folding case are preferably such that the case can be carried in a pocket or purse when it is folded into the closed position.

Abstract: A hinge function y=h(x) consists of two hyperplanes continuously joined together at a hinge. In regression (prediction), classification (pattern recognition), and noiseless function approximation, use of sums of hinge functions gives a powerful and efficient alternative to neural networks with computation times several orders of magnitude less than is obtained by fitting neural networks with a comparable number of parameters. A simple and effective method for finding good hinges is presented. >