This thesis concerns stressed spline structures. A spline is defined as `an initially straight member with identical second moment of area about any axis perpendicular to its centroidal axis, bent into a spatial curve'. An analytical proof is presented to show that the spline's torsional stiffness is of no importance in its analysis (provided construction details do not introduce any torsional moment). This paramount proof allows the formulation of a spline analysis that relies solely on three translational degrees of freedom (3DOF) per node. Applying this 3DOF analysis to unstrained curves and battened or hoop supported membranes is approximate since the bending stiffness would correspond to one direction only. A series of four test cases validates the proposed 3DOF analysis. The analysis is first applied to a laterally loaded spline ring, where solution convergence and the effect of unequal length segment modelling are investigated. Most significantly, this test case demonstrates that the spline ring has a greater out-of-plane stiffness than a pre-bent ring. This feature lies at the basis of spline stressed membranes - the spline has superior out-of-plane stiffness under the action of forces applied by the membrane. The second and third test cases -- buckling of elastica and of a shallow sinusoidal arch -- clearly demonstrate that the 3DOF analysis is much faster, more accurate, and produces results closer to the analytical values compared with a 6DOF analysis. The fourth test case proves the efficiency of the 3DOF analysis through investigating buckling behaviour and loads of four circular arches under radial loading. As the torsional stiffness does not enter the 3DOF analysis, the stiffness of a spline constructed of spliced segments is identical to that of a continuous spline. In order to demonstrate their feasibility, five medium span (161n-32m) Glass Fibre Reinforced Plastic (GFRP) and one large span (57nt) steel tensegrity stressed spline membranes are designed, form-found and analysed under realistic loading conditions. These design studies show firstly that the spline and membrane stresses occurring under loading are within acceptable material limits and secondly that buckling occurs at values much higher than those encountered in reality. This thesis has demonstrated that engineered stressed spline structures, for which the development of a 3DOF was essential, have great design potential.

Finite element is used to predict the torsional stiffness and natural frequency response of a FSAE vehicle hybrid chassis, utilizing a carbon fiber reinforced polymer sandwich structure monocoque and a tubular steel spaceframe. To accurately model the stiffness response of the sandwich structure, a series of material tests for different fiber types has been performed and the material properties have been validated by modeling a simple three-point-bend test panel and comparing the results with a physical test. The torsional stiffness model of the chassis was validated with a physical test, too. The stiffness prediction matches the test results within 6%. The model was then used to model the natural frequency response by adding and adjusting the materials’ densities in order to match physical mass properties. A hypothesis is made to explain the failure of the engine mounts under the dynamic response of the frame.

This thesis details the development of Finite Element Analysis (FEA) techniques to simulate assembly and functional performance of football boots within a virtual environment. With a highly competitive market and seasonal changes in boot design common, the current design process can require numerous iterations, each adding time and cost to the development cycle. Using a reliable model allows evaluation of novel design concepts without the necessity to manufacture physical prototypes, and thus has potential financial benefits as well as reducing development time. A modelling approach was developed to construct a three dimensional boot model using FEA techniques, simulating the assembly of representative boot constituent parts based on manufacturing patterns, geometries and materials. Comparison between the modelled and physical boots demonstrated good agreement. Assessment of physical boot manufacture enabled the validation of the simulated assembly techniques, with digital image correlation hardware and software used to provide experimental measurements of the surface deformation. Good agreement was reported, demonstrating the predictive capabilities of FEA. Extensive review of literature provided applicable loading conditions of the boot during game play, with bending and torsional stiffness identified as important parameters. Boundary conditions associated with the foot during these movements provided a platform from which mechanical tests were used and developed to quantify boot function. Modelling techniques were developed and applied to the assembled FEA boot model, simulating the loading conditions to verify the validity when compared with experimental measurements. Bending and torsional stiffness extracted from the model were compared with the physical equivalent, demonstrating good predictive capabilities. The model was able to represent bending stiffness of the physical equivalent within 5.6% of an accepted boot range up to 20°, with torsional stiffness represented within the accepted range between 10° inversion to 7.5° eversion, corresponding to a large proportion of match play. Two case studies proved the applicability of the FEA techniques to simulate assembly and determine mechanical functionality virtually through a combination of automated modelling methods and a bespoke framework, demonstrating how it could be implemented within the industrial design process.

Continuum manipulators which are robot limbs inspired by trunks, snakes, and tentacles, represent a promising field in robotic manipulation research. They are well known for their compliance, as they can conform to the shape of objects they interact with. Furthermore, they also benefit from improved dexterity and reduced weight compared to traditional rigid manipulators. The current state of the art continuum robots typically consists of a bulky pneumatic or tendon-driven actuation system at the base, hindering their scalability. Additionally, they tend to sag due to their own weight and are weak in the torsional direction, limiting their performance under external load. This work presents an origami-inspired cable-driven continuum manipulator module that offers low-cost, light-weight, and is inherently safe for human-robot interaction. This dissertation includes contributions in the design of the modular and torsionally strong continuum robot, the motion planning and control of the system, and finally the embedded sensing to close the loop providing robust feedback.

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The Master’s thesis deals with the design and production of a composite chassis of the new formula Dragon X. The carbon prepreg used for manufacturing of the monocoque was to be operated at high temperatures. Therefore, this thesis deals with the application of composites structures in the high temperature environment. The thesis addresses the torsional stiffness problematics and it was not only physically tested, but also simulated by FEM analysis and the results were compared.

Pavel Chalupa Torsional Stifness Analysis of Formula Student Frame Modification DW, IAE, 2010, 66 str., 66 obr. This thesis is concerned with a calculation analysis of a frame construction for Formula Student. The Base design of this construction is modeled in computer program ProEngineer. In next step the model is transfered to calculation software Ansys. The analysis is made by finite element method in torion and bend there. The calculation of torsional stiffness is made of resultant values. Finally, the results are compared with previous frame versions.

The goal of this diploma thesis is to design a frame for an experimental vehicle. The primary object is to design a conception and layot of a drive unit. The frame design is followed by a creation of a model for an analysis. The model will serve for torsional stiffness computing using FEM analysis software. After evaluation of results additional chanhges of the design may take place. A vehicle will serve for testing combustion engines of the same conception and thus it is not intended to run on public roads.

This master’s thesis describes the design of the Baja SAE vehicle according to the applicable rules. In the beginning is the work focused on search competing vehicles and subsequently on design the first Baja SAE vehicle in the Czech republic. This thesis is systematically divided into chapters according process to the vehicle design. The main part of a master's thesis is design of axle kinematics in software Adams and frame design. The model was designed in Catia V5. The frame was analysed of torsional stiffness and stress in software ANSYS.

Those theses describe torsional stiffness car chassis. Here is write short knowledge about various type of measuring, explain impact torsional stiffness on car handling. Target of this theses is work out structural proposal of device for measuring torsional stiffness car chassis, suitable method of measuring, calculate measurement mistake and provisional cost calculation.