Therefore, a general closedform solution for flexure hinges of different profiles that incorporates the profile selection and parameter design will be of great benefit to the hinge design. Pdf a generic compliance modeling method for twoaxis. Flexures will produce these motions without any friction or hysteresis down to the subnanometer level, and they never need lubrication. Forthesecalculations,thegeometryofthe3d hinge is modelled using a 2d quarter of the model, shown in fig. Synthesis of precision serial flexure systems using freedom. An improved modeling approach for circular flexure hinges with application to geometry. This article presents the comparison of various compliancestiffness equations of circular flexure hinges with fea results. We also plan to offer a variety of quartz flexure accelerometers ranging in size, weight and application usage. Based on the limitations of these design equations, a guideline for selecting the most accurate equations for hinge design. He studied the stress distribution at all flexure joints, modal analysis and the workspace. Pdf a new generalized model for elliptical arc flexure. The paper focuses on the development of design equations that can accurately predict the behavior of such stages especially the lost motion due to hinge stretching. Torsional stiffness of several variable rectangular crosssection. Dec 07, 2017 the flexure hinge of claim 15 wherein the cross section of the thin spot defined by the intersection of the direction x and direction z plane at the thin spot has the shape of one or more rectangles.
Later cornerfilleted flexure hinges were designed and analyzed by lobontiu et al. Deformation effect outside flexure hinge geometry figure was provided by schotborgh. Each of these hinge types is described by a parameterized geometric model. A precision stage employing a lever mechanism and flexure hinges is analyzed theoretically, with bending in the lever considered. This paper presents the dimensionless empirical equations and graph expressions of three flexure hinges for compliant mechanism designs. Simplified optimum design of flexure hinges we measure the locations of hinge like rotational axis obtained by the firststage topology. A flexible multibody modeling approach is used for efficient modeling. There are several examples on the wikipedia page, but i would add in addition to those examples that probably the most common flexure bearing would be the. Analysis and design of symmetric notch flexure hinges. A flexure bearing is a bearing which allows motion by bending a load element. The paper introduces a common twoaxis ellipticalarcfilleted flexure hinge that is generated by two different ellipticalarcfilleted cutout profiles and that provides some new hinge types. A design method for flexurebased com pliant mechanisms.
The significance of this effect are currently being investigated and will be revealed in near future. A special flexure hinge is adopted to actuate the single stage in three axes at the same time. The limitation of these equations at different t r r is the radius and t is the neck thickness ratios are revealed. Pdf an improved modeling approach for circular flexure. Pdf material coherent flexure hinges allow a specific geometrical design of. This study investigates a number of commonly used flexure hinges to determine a flexure hinge. The paper introduces a new class of twoaxis flexure hinges with axiallycollocated and symmetric notches as an alternative to the existing flexure. On modeling the bending stiffness of thin semicircular.
Each pair of flexible hinges is mutually perpendicular to another pair of flexible hinges and is also perpendicular to. Lever mechanisms are usually used to enlarge output displacements in precision stages. Three flexure hinges for compliant mechanism designs based. Flexure stages may also be bought from the following vendors. Pdf the influence of asymmetric flexure hinges on the axis of. The simplest form of flexural hinge is the cantilever flexure. The flexure hinge has the highest accuracy, when the bending point is located in the centre of the hinge 7. Leaf springs are an example of a flexure system with one compliant degree of freedom. Design and analysis of a highaccuracy flexure hinge.
Unlike the conventional rotational joint which is constructed by different rigid parts, the. Design of flexure hinge mechanism for dynamic yaw control of fpd lithography stage dahoon ahn1, hyunchang kim1, daegab gweon1 sunho lee2, woohyuck choi2, sungtaek baek2 sanghoon lee2 junkyu park2. Leaf springs are commonly used in vehicle suspensions. Design of a flexural hinge mechanism for turbo slits. Combining equations 24 results in displacement components u. Dec 27, 2002 flexure hinges hold several advantages over classical rotation joints, including no friction losses, no need for lubrication, no hysteresis, compactness, capacity to be utilized in smallscale applications, ease of fabrication, virtually no assembly, and no required maintenance. Design of flexure hinges provides practical answers and directions to the needs of efficiently designing, analyzing, and optimizing devices that include flexure hinges. Review of circular flexure hinge design equations and.
In order to accurately calculate the above parameters, this article. The circular hinge the dimensionless design graph for the circular. Design and experiment of a 3dof parallel micromechanism utilizing flexure hinges byungju yi, member, ieee, goo bong chung, heung yeol na, whee kuk kim, member, ieee, and il hong suh, senior member, ieee abstract flexure hinge has been commonly used as a substitute for mechanical joints in the design of micropositioning mecha. Flexure hinge, stiffness, rotational precision, hinge index. A simple compliance modeling method for flexure hinges. This invention relates to improvements in a flexure joint for connecting a pair of members for relative angular displacement about a hinge axis, the joint comprising a pair of leaf springs which cross each other and merge at their ends with the members. Pdf this article presents the analytic models of four types of flexure hinges elliptic, circular, parabolic. Modeling and design of flexure hingebased compliant.
This paper designs and analyzes a new kind of flexure hinge obtained by using a topology opti mization. The obtained optimal hinge designs are validated with a finite element model and show good agreement. Static deformation modeling and analysis of flexure hinges. Flexure bearings are often part of compliant mechanisms. What id like to do now is rotate the two halves along that flexure hinge. Fliptop on a shampoo bottle piezobeams on a scanning tunneling microscope because of the bending stresses created in the flexure. Large stroke performance optimization of spatial flexure. Jan 23, 2010 in this paper, a new twodimensional, compliant, monolithic piezoactuated microgripper using flexure hinges is reported. Hinge swaging swaging is a slight offset of the hinge leaf at the barrel which permits the leaves to come closer together when parallel hinges are. The stage considered here is composed of flexure hinges, piezoelectric actuators and their peripherals. Flexure hinge has been widely used in high precision micropositioning mechanism and the most common type is right circular flexure hinge. Combining the results of chen 16, the correct stiffness.
Pdf analysis and design of symmetric notch flexure hinges. Flexure hinges and torsion suspensions are devices which connect or transmit load between two. When the hinge thickness is divided into n parts, the symmetrical prismatic joint is composed of n flexure hinges, and the thickness of each flexure hinge is tn. Relations between design parameters and magnification ratio, and the optimal values for the parameters to achieve a longer stage displacement are presented. For the fembased investigations, the variable hinge height k x of all flexure hinges. An improved modeling approach for circular flexure hinges with application to geometry optimization. Flexure joint, particularly for connecting a gyroscope to its. Deshmukh3 1,2 department of mechanical engineering, sinhgad institute of technology, lonavala. A design method for flexurebased com pliant mechanisms on. Based on the limitations of these design equations, a guideline for selecting the most accurate equations for hinge design calculations are presented.
The aspect of this deformation effect on the hinge compliances is beyond the scope of this paper. A twostage topological optimum design for monolithic. A cantilever flexure is a single leaf or notched flexure rigidly clamped between the two sections of a mechanism with one fixed and one free to rotate. A compliant mechanism gains its mobility fully or partially from the compliance of its elastically deformable parts rather than from conventional joints. A general approach for the design of flexurehinge type lever mechanisms that are commonly used in the design of translational micropositioning stages is presented in this paper. Modeling and analysis of deformation on a flexure bearing in linear compressor vennapusa v sivareddy1 corresponding author. During the optimization, constraints are applied to the.
Numerous studies have been made for the design of flexure hinges and compliant mechanism 2327. Pdf analysis and design of a spherical micromechanism. Many kinds of flexure profiles were proposed during the past decade. In this paper, a new twodimensional, compliant, monolithic piezoactuated microgripper using flexure hinges is reported. See microsystem design by senturia for more information. Optimal design of a flexurehinge precision stage with a.
Flexure bearings serve much of the same function as conventional bearings or hinges in applications which require angular compliance. Pdf modeling and design of a twoaxis elliptical notch. If you have a user account, you will need to reset your password the next time you login. The stiffness and rotational precision of flexure hinges are the most crucial factors to be considered during the flexure hinges design. A flexure can be used to reproduce almost perfect linear or rotary motion or a combination of both. Pdf comparison of circular flexure hinge compliance. This paper establishes four models of ushaped flexure hinges with different notch shapes and structure parameters, and presents the closeform compliance equations for the four structure types of. For the fembased investigations, the variable hinge height k x of all flexure hinges of the compliant h. It contains readytouse plots and simple equations describing several flexure types for the professional that needs quick solutions to current applications. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Analysis and design of a spherical micromechanism with flexure hinges. This paper establishes four models of ushaped flexure hinges with different notch shapes and structure parameters, and presents the closeform compliance equations for.
Therefore, the chapter provides a survey of different methods for the general and simplified modeling of the elastokinematic properties of flexure hinges and compliant mechanisms for four hinge. The flexural hinge has a welldefined rotation axis normally defined geometrically by the axis of the reference. Due to many advantages, in particular the smooth and repeatable motion, monolithic mechanisms with notch flexure hinges are state of the art in numerous precision engineering applications with required positioning accuracies in the. Proposed magnetically actuated soft capsule endoscope masce. For combining the advantages of different notch contours. Abstract this article presents the comparison of various compliancestiffness equations of circular flexure hinges with fea results. Flexure hinges have been used in many engineering areas where high precision and sensitivity are required. Torsional stiffness of several variable rectangular cross. As a kind of important flexible joint, twoaxis flexure hinges can realize inplane and outofplane motions and can be used for constructing flexure based spatial compliant mechanisms. A twoaxis, monolithic, flexure hinge suspension system for an accelerometer or gyroscope has first, second and third cylindrical portions which are slightly axially spaced from each other along a common axis and are connected by pairs of flexible hinges therebetween. A general concept of flexural hinge is composed by three elements. Analytical solution of stiffness for a cornerfillet leaf. The loads and the corresponding small deformations at t.
Therefore, a symmetric circular flexure hinge is suitable for ultra precision positioning system. Investigation of circular flexural hinge used in compliant. The optimal solution of the butterfly flexure hinge shows the least decrease in the supporting stiffnesses of the evaluated hinges. A compact 2dof piezoelectricdriven platform based on z. Force balanced quartz flexure accelerometers jewell instruments. Flexi hinge is a compact, versatile, easytoinstall device which requires no maintenance, offers indefinite life and is resistant to detrimental environmental conditions. The measure of performance is defined by the first unwanted natural frequency, which is closely related to the supporting stiffnesses.
The results shows that the elliptical flexural hinge has less stress for the similar displacement, the corner filleted flexural hinge was the most accurate in the sense of motion. Culpepperb a lawrence livermore national laboratory, l223 7000 east avenue, livermore, ca 94551, usa b mit department of mechanical engineering, room 35209, 77 massachusetts avenue, cambridge, ma 029, usa a r t. Hinge swaging swaging is a slight offset of the hinge leaf at the barrel which permits the leaves to come closer together when parallel hinges are slightly less in width when both leaves are not swaged. The length of travel of this very accurate motion is, however, quite limited. The developed stage makes use of magnetically preloaded pzt actuators and a ball contact mechanism to avoid the crosstalk among the axes. For mems, the fabrication process is complex and errorprone. Flexures me en 7960 precision machine design topic 12 me en 7960 precision machine design flexures 122 general flexural bearings are widely used in practice application range from. Multiaxis nano positioning flexure stage using magnetically. The paper introduces a new class of twoaxis flexure hinges with axiallycollocated and symmetric notches as an alternative to the existing flexure designs with seriallydisposed notches. Flexure hinges are materially coherent connections between two bodies or body segments with at least one relative motion due to mostly elastic deformation 5. Preferred for their simplicity, as they can be included as a feature in a single piece of material as in a tic tac boxs lid. The actual part is much more complicated, including various facets, curves, and cuts, so im not sure how to rotate the sections to open up the part. Calculation on rotation stiffness of asymmetrical right.
The flexure hinge of claim 15 wherein the cross section areas spaced apart along the direction z comprise a plurality of identical geometric. Us4694703a circumferentially oriented flexure suspension. It is a parallel mechanism of high stiffness, which can offer 6 degrees of freedom, with its size controlled under 100 mm x. Large stroke performance optimization of spatial flexure hinges. The inplane and outofplane stiffnesses of the flexure hinges are developed. Mar 01, 2011 the split is 5mm long, leaving a 1mm flexure hinge that connects the two halves, so that the part opens up like two jaws.
This paper designs and analyzes a new kind of flexure hinge obtained by. Design of flexure hinge mechanism for dynamic yaw control of fpd lithography stage dahoon ahn1, hyunchang kim1, daegab gweon1 sunho lee2, woohyuck choi2, sungtaek baek2 sanghoon lee2 junkyu park2 1department of mechanical engineering korea advanced institute of science and technology. Important material properties for various applications of flexure hinges and torsion suspensions. Highly accurate, even after a lifetime of cycling, flexihinges offer the optimum solution for many of todays engineering problems. Due to many advantages, in particular the smooth and repeatable motion, monolithic mechanisms with notch flexure hinges are state of the art in numerous. A cantilever is a flexural beam rigidly supported at one end only. Firstly, asymmetrical right circular flexure hinge is presented and the structure factor is introduced in the paper according to the size of the cutting arc radius of both sides of right circular flexure hinge.
Request pdf a simple compliance modeling method for flexure hinges various types of flexure hinges have been introduced and implemented in a variety of. A onepiece 3d printed flexure translation stage for open. The microgripper is designed, and a comparison study on stress and displacement is done by varying the hinge parameters such as the hinge radius, web thickness, position of flexure hinge, and radius of curvature of hinges. A onepiece 3d printed flexure translation stage for opensource microscopy james p. This novel flexure based mechanism is capable of delivering planar motion with three degrees of freedom 3dof.
Modeling of flexurehinge type lever mechanisms sciencedirect. A continuously description regarding this part is given in the next paragraph. A symmetric circular flexure hinge has the bending point in the centre of the hinge. Pdf modeling and design of flexure hingebased compliant. As an important part of the joule balance system, the twoaxis elliptical notch flexure hinge tenfh which typically consists of two singleaxis elliptical notch flexure hinges was studied. Design and performance optimization of large stroke. The flexures may be broken when removing them from the laser cutter. Design of flexure hinges provides practical answers to the present and future needs of efficient design, analysis, and optimization of devices that incorporate flexure hinges. A flexure bearing is a category of flexure which is engineered to be compliant in one or more angular degrees of freedom. Design and experiment of a 3dof parallel micromechanism. Calculation of the zshaped flexure hinge flexure hinges are widely exploited in piezoelectricdriven platforms, due to their unique superiorities.
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