Flexures are usually thin as we want to minimize the spring force for moving them.Infinite life can be achieved if you do not use up all the elastic range. No need to lubricate, no wear, infinite life, no backlash.Flex pivots or cross hinge pivots it works over small angles.Flextures are limited by the elastic range of the material, even in good steel, the elastic range is 1%, so for large travels its best to have Nitinol, which has an elastic range 10 times as much as steel.Aluminum is used for prototyping but they are very temperature sensitive and cannot be used for fine positioning.So drill and ream the holes, align on waterjet. If you want a high accruacy flexture, you need to pre-drill the holes because, how well this moves, how linear it is depends on the exact mataching of the pivot points.The connecting pieces are called Wiggle bar they are effectively used to decouple the rotational motion of the frame from the linear motion.In flextures, you can not only make a linear stage, but also reduction stages to couple the motion and provide leverage.In the stress strain curve of a material, the slope of the curve in the elastic region is the Youngs modulus Which is the stiffness.Question is, if there are two vector forces on the body does that give it 8 degrees of freedom or will the forces combine to a resultant The inevitable flexibility of all the structures is the seventh degree of freedom Elasticity isn’t really the seventh degree, the deflection caused by an applied force accounts for that degree of freedom. But there is no such thing as a rigid body. conventional wisdom says that there are only six degrees of freedom, but that assumes that the constrained bodies are rigid.As you make the flexure thinner, the center of rotation of the flexure is more defined, this help with calculations in micro Actuators Also when flexures are connected in parallel they tend to cancel out any parasitic motion and help define the center of rotation better.Flexures are bearings with limited range of motion, they have no backlash and last long with good material.Links between origami and compliant mechanism.Integral Mechanical Attachment, 1st Edition by R.Design modeling and fabrication of experimental apparatus for compliant mechanism education kit by Sarah E.Customized digital manufacturing : concept to construction methods across varying product scales by Marcel Botha.Digital materials for digital fabrication by George A.Additive assembly of digital materials by Jonathan Ward.Snap-Fit Joints for Plastics - A Design Guide by BAYER.Snap-Fits for Assembly & Disassembly by Tim Spahr (PDF).MIT paper Sara Design of educational Flextures # Dspace MIT.Principles for desigining Precision Machines MIT.Precision design Lab University of Michigan.Flexture encyloperdia precision balls learning.Precision Balls catalogue of Flextures learning.Spherical Flextures Motion reduction, resolution enhancement.Spherical flextures with tetrahedron joints.
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