This work investigates a new error source for angular velocity or attitude-based transfer alignment, which is caused by the coupling influence of dynamic flexure with ship angular motion. Most traditional studies do not consider this coupling error, as they often assume that dynamic flexure and ship angular motion are uncorrelated. However, the correlation between the dynamic flexure and the sh...

This paper presents the design of a selective-actuation flexure parallel mechanism that can provide three de-coupled micro-motions along the X-, Y and Z-axes. This mechanism can be used as an ultra-precision positioning system. The modeling of this flexure parallel mechanism is then established based on a pseudo-rigid-body model with consideration of deformation of the flexure member. The facto...

Cavitation damage in flexure bars crept at 1170°C was studied by a density measurement technique. The cavity density within the flexure beams could be approximated by a linear function of position from the tensile surface. A threshold stress for cavitation damage is suggested from the results of this study. Below the threshold tensile stress, cavitation ceases, whereas above the threshold, cavi...

Fl substitute for positioning m flexure hinge paper, a p mechanism is hinge modeli that includes analytic stiffn presented. Fir considered. T not coinciden axial elongat mechanism f problem, a 2 additional mo part. On the ensured. The through both emphasizes t significant to micro-mechan Micro positi technology i Microscopy ( micro machin studies on t mechanisms (Moriyama, e Ryu, et al. [4] mod...

This paper focuses on the complex design process of planar compliant mechanisms with flexure hinges. In the following a systematic methodology of the transition from lever mechanisms generated intuitively by the developer or non-intuitively by topology optimization to applicable compliant mechanism is presented. An extended pseudo-rigid-body model (PRBM) is used for the analysis and the modific...

This paper presents parallel kinematic XY flexure mechanism designs based on systematic constraint patterns that allow large ranges of motion without causing over-constraint or significant error motions. Key performance characteristics of XY mechanisms such as mobility, cross-axis coupling, parasitic errors, actuator isolation, drive stiffness, lost motion, and geometric sensitivity are discuss...

This paper proposes a novel analytical model for flexure-based proportion compliant mechanisms. The displacement and stiffness calculations of such flexure-based compliant mechanisms are formulated based on the principle of virtual work and pseudo rigid body model(PRBM). According to the theory and method, a set of closed-form equations are deduced in this paper, which incorporate the stiffness...

The fabrication route for tidal turbine blades has been compounded with the appearance of additive manufacturing; use infill patterns, improvement mechanical strength and material reduction 3D printed parts can be obtained. Through finite element analysis three-point bend tests, optimal lattice pattern, viability shell–infill blade model as an alternative to conventional shell-spar was determin...

This paper presents the effect of the accuracies of flexure hinge compliance equations (the accuracies vary with a geometrical ratio, t/R of a hinge) on the output compliances of RRR and 3-RRR micro-motion stages. Closed-form output compliance models of the stages are derived (with flexure hinge compliances as one of the variables) to investigate the aforementioned effect. The output compliance...

INTRODUCTION Volvulus of the splenic flexure (VSF) is a rare cause of intestinal obstruction (1). Patients usually present with recurrent episodes of intestinal obstruction and there is a slight female preponderance. The affected patients usually have identifiable risk factors including previous surgery involving mobilization of the splenic flexure with resultant adhesions, congenital absence o...