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Showing 1 to 20 of 43 for “"variable-stiffness"”.
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Pneumatic variable stiffness soft robot end effectors
… This research presents the design of a variable stiffness, soft, three-fingered dexterous gripper. The gripper uses contractor pneumatic muscles to control the motion of soft fingers. The soft nature of the gripper means it can deform if it collides with obstacles, and because grasping …
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Analysis of Tow-Placed, Variable-Stiffness Laminates
… which is composed of such plies will have stiffness properties which vary as a function of position. Previous work had modelled such variable-stiffness laminae by taking a reference fiber path and creating subsequent paths by shifting the reference path. This thesis introduces a method …
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Analysis and Design of Variable Stiffness Composite Cylinders
… cylindrical shells through the use of the variable stiffness concept is presented. The variable stiffness concept implies that the stiffness parameters change spatially throughout the structure. This situation is achieved mainly through the use of curvilinear fibers within a …
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Design of Variable Stiffness Composite Panels for Maximum Strength
… of this research is to explore the design of variable stiffness composites and develop an automated framework to model, analyze and optimize these structures. Variable stiffness composites have been shown to exhibit increased strength and stiffness over traditional constant stiffness …
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Design of A Variable-Stiffness Ankle-Foot Orthosis Emulator
… palsy. They are characterized by a torsional stiffness and ankle neutral angle. For this project, a lightweight ankle exoskeleton was designed to emulate the spring-like behavior of a traditional AFO for a wide range in torsional stiffnesses and neutral angles. This was achieved by utilizing …
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Optimal variable stiffness feedback control for structural vibration suppression
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1993.
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Finite Element Modeling of Tow-Placed Variable-Stiffness Composite Laminates
… The result is a laminate with spatially varying stiffness and response. This manufacturing method can also result in overlap regions between adjacent tow paths. In previous research, a closed-form solution was developed to determine the response of these variable-stiffness laminates, but the …
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Design, Analysis and Experimental Evaluation of 3D Printed Variable Stiffness Structures
… AM, testing and simulation of advanced optimized variable-stiffness structures. The first part offers an insight on the mechanical, viscoelastic and failure characteristics of AM continuous fiber composites. This understanding was used in the second part to investigate the feasibility of different …
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Optimal Design of Variable-Stiffness Fiber-Reinforced Composites Using Cellular Automata
… limitations have to be removed. The concept of variable-stiffness laminates allows the stiffness properties to vary spatially over the laminate. Through tailoring of fiber orientations and laminate thickness spatially in an optimal fashion, mechanical properties of a part can be improved. In …
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Variable stiffness orthosis for gait normalization in patients with toe walking
… support with an orthosis, a custom orthosis with variable stiffness cushioning was designed. A healthy subject walked with simulated tip toe walking observed in DMD and ITW patients on a treadmill for three thirty-second trials, each with a cushioning material of rubber, gel, or foam added to the …
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Applications of force actuators and variable stiffness systems with base isolation
… with significantly increased strengths, but the stiffness of these materials have not increased at the same rate. Motion parameters control the design for these high-strength materials. Finally, recent earthquake responses have shown that repair costs from structural damage due to inelastic …
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A Variable Stiffness Energy Dissipation Device for Vibration Control of Steel Frames
… this research, a new device called the variable stiffness energy dissipation device is conceptualized and numerically studied. Using nonlinear time history analysis, results are obtained to illustrate the effectiveness of the proposed device in enhancing the seismic performance of shear …
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Multiscale finite element models for the analysis, design and optimisation of variable stiffness composites
L'abstract è presente nell'allegato / the abstract is in the attachment
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Investigation of Polymer-Filled Honeycomb Composites with Applications as Variable Stiffness Morphing Aircraft Structures
… While these can serve to increase the stiffness of the composite, there is still a present need for reinforcement strategies that can also maintain the large changes in stiffness of shape memory polymers. An alternative shape memory composite relies on honeycomb materials with shape …
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Use of axiomatic design principles to develop vehicle suspension controls for variable stiffness and ride height
… independent suspension system in which the FRs stiffness, ride height, and damping can be varied as needed. To achieve the three FRs, three DPs are chosen - the volume of an air spring for stiffness, the volume of fluid in a fluid chamber for ride height, and orifice control for damping. This …
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Design and Evaluation of a Quasi-Passive Variable Stiffness Ankle-Foot Prosthesis to Improve Biomechanics Across Walking Speeds
… achieved by automatically adjusting prosthesis stiffness to maximize energy storage across walking speeds. A novel quasi-passive variable stiffness ankle-foot prosthesis is presented with high resolution stiffness adjustment from 352 - 479 Nm/radian, corresponding to biological ankle …
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The biomechanical effect of different types of footwear on medial compartment knee loading during stair ascent and descent
… shoe, mobility shoe, Melbourne OA shoe and variable stiffness shoe) during stair ascent and descent. Each participant performed five valid trials of stair ascent and descent for both limbs under each condition. Repeated measures ANOVA and Friedman’s ANOVA were used for statistical analysis. …
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Adaptive robust interaction control for low-cost robotic grasping
… grasp, the mechanical properties of the object (stiffness and damping) will play an important role. A gripper which is stable in isolated conditions, can become unstable when coupled to an object. This can lead to the extreme condition where the gripper becomes unstable and generates excessive or …
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Compression and buckling of composite panels with curvilinear fibers
… the length of a composite laminate results in stiffness properties that change as a function of location. The laminates are therefore termed variable stiffness panels. This work presents an analysis of the stiffness variation and its effect on the in-plane and buckling response of the panel. …
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