Horseshoes are manufactured metal plates developed in an extensive assortment of materials and shapes and their main function is to protect the horse’s hooves and legs against abrasion and rupture. After a certain period of time the horseshoes are lost, worn out, or the hoof needs to be treated. Horseshoeing is a repetitive time consuming process for the farrier who has to heat the horseshoe inside a forge until it reaches the required temperature and shape it with a hammer until it fits perfectly to the horses’ hoof. The main goal of this project is to develop a horseshoe bending machine able to shape the horseshoe so its shape fits perfectly the horse’s hoof. The calculation of the bending force needed to be applied to the horseshoe in order to provoke a plastic deformation will be done with Euler-Bernoulli beam theory. The bending force is then used to design and dimension each element of the bending mechanism so that it may be able to resist the stresses and prevent the parts from collapsing during its working life span. A study of the springback effect will be done followed by the analysis of the hertzian contact stresses between the rollers and the horseshoe. In addition, a clamping system is selected to constrain the movements of the horseshoe during the bending process. This machine will reduce the final user’s horse maintenance costs at the same time that makes the fitting process easier and less demanding, which will improve the farrier’s working life span and quality.

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Indiana University-Purdue University Indianapolis (IUPUI) / Lattice structures have seen increasing use in several industries including automotive, aerospace, and construction. Lattice structures are lightweight and can achieve a wide range of mechanical behaviors through their inherent cellular design. Moreover, the unit cells of lattice structures can easily be meshed and conformed to a wide variety of volumes. Compliant mechanism make suitable micro-structures for units cells in lattice structures that are designed for impact energy absorption. The flexibility of compliant mechanisms allows for energy dissipation via straining of the members and also mitigates the effects of impact direction uncertainties. Density-based topology optimization methods can be used to synthesize compliant mechanisms. To aid with this task, a proposed optimization tool, coded in MATLAB, is created. The program is built on a modular structure and allows for the easy addition of new algorithms and objective functions beyond what is developed in this study. An adjacent investigation is also performed to determine the dependencies and trends of mechanical and geometric advantages of compliant mechanisms. The implications of such are discussed. The result of this study is a compliant mechanism lattice structure for impact energy absorption. The performance of this structure is analyzed through the application of it in a football helmet. Two types of unit cell compliant mechanisms are synthesized and assembled into three liner configurations. Helmet liners are further developed through a series of ballistic impact analysis simulations to determine the best lattice structure configuration and mechanism rubber hardness. The final liner is compared with a traditional expanded polypropylene foam liner to appraise the protection capabilities of the proposed lattice structure.

Constant-force mechanisms are mechanical devices that provide a near-constant output force over a prescribed deflection range. This thesis develops various optimization-based methods for designing robust constant-force mechanisms. The configuration of the mechanisms that are the focus of this research comprises a cam and a compliant spring fixed at one end while making contact with the cam at the other end. This configuration has proven to be an innovative solution in several applications because of its simplicity in manufacturing and operation. In this work, several methods are introduced to design these mechanisms, and reduce the sensitivity of these mechanisms to manufacturing uncertainties and frictional effects. The mechanism's sensitivity to these factors is critical in small scale applications where manufacturing variations can be large relative to overall dimensions, and frictional forces can be large relative to the output force. The methods in this work are demonstrated on a small scale electrical contact on the order of millimeters in size. The method identifies a design whose output force is 98.20% constant over its operational deflection range. When this design is analyzed using a Monte Carlo simulation the standard deviation in constant force performance is 0.76%. When compared to a benchmark design from earlier research, this represents a 34% increase in constant-force performance, and a reduction from 1.68% in the standard deviation of performance. When this new optimal design is evaluated to reduce frictional effects a design is identifed that shows a 36% reduction in frictional energy loss while giving up, however, 18.63% in constant force.

Lamina emergent mechanisms (LEMs) can provide a way to meet the demand for more compact and inexpensive mechanisms. Previous research has developed LEM designs and identified applications for them, but many applications would benefit from suitable actuation techniques. This thesis presents the design considerations and a variety of applicable methods for internal and external LEM actuation in the macro scale. Integrated LEM actuator possibilities have been identified, each with its advantages and disadvantages depending on the application. Shape memory alloys are especially compatible with LEMs. Traditional actuators have also been discussed as a way of actuating a LEM from the outside for cases in which space constraints allow it. The feasibility of new internal actuators using basic actuation principles, especially flat solenoids, has been explored. The magnetic field distribution along the axis of a high-aspect-ratio solenoid has been derived. Analytical and experimental results show that the output force of a high-aspect-ratio solenoid is suitable for LEMs. A pseudo-solenoid conceptual prototype was manufactured and evaluated, revealing challenges for which solutions have been recommended.

Origami is making an impact in engineering as solutions to problems are being found by applying origami principles (eg. flat-foldability) and using specific crease patterns as inspiration. This thesis presents an in-depth analysis of a particular origami fold -- the waterbomb base -- to facilitate its use in future engineering problems. The watebomb base is of interest due to its familiarity to the origami community, simple topology (can be made by folding a single sheet of paper four times), scalability, generalizability, and interesting kinetic behavior. It can behave as a nonlinear spring as well as a one- or two-way bistable mechanism. This thesis presents models of the kinetic behavior of the traditional waterbomb base as well as some non-traditional variants to be used as tools in future development of waterbomb-base-inspired mechanisms. In all cases considered here, developability as well as rotational symmetry in both the geometry and motion of the mechanisms are assumed. The thesis provides an introduction to origami and reviews some of the ways in which it has been studied and applied in engineering fields. The waterbomb base is also presented as a specific origami fold with practical application potential. Models for the behavior of the traditional waterbomb base are introduced and its potential usefulness as a testbed for actuation methods is discussed. Models are developed for its kinematic and bistable behavior, including the forces needed to transition between stable states. These models are validated by comparison to physical prototype testing and finite element analysis. The thesis introduces the generalized waterbomb base (WB) and generalized split-fold waterbomb base (SFWB). The WB maintains the pattern of alternating mountain and valley folds around the vertex but in this generalized case any even number of folds greater than or equal to 6 is allowed. An SFWB is created by splitting each fold of a WB into two “half folds”, effectively doubling the number of folds and links but halving the deflection at each fold. The same models that were developed for the traditional waterbomb base are developed for the WB and the SFWB and a few potential applications are discussed.

With the increase of global temperature and decrease of fossil fuel sources, biofuels become an excellent alternative in present days. Because of its oxygenated nature, biofuels are found to be more environmentally friendly over fossil fuels. Therefore, in this study, initially two different biofuels: ethanol and 2,5 dimethyl furan (DMF) are considered as an additive to gasoline which shows a significant improvement in its combustion characteristics. Due to this promising result for further studies of these biofuel, details chemical kinetic study of biofuels is considered in this work through generating its mechanism for engine relevant conditions. Detail chemical mechanism PCRL-Mech1 is generated for ethanol which is applicable for wide range of operating conditions. The mechanism is successfully validated with available experimental data of laminar burning speed (LBS) and ignition delay time (IDT). Species concentration at different reactor conditions are also considered for the comparison which shows an excellent agreement. Detail mechanism generation for another newer biofuel anisole is also considered because of its favorable features in combustion properties and potential source of biomass. Anisole is a higher hydrocarbon aromatic component and comparative newer fuel which has limited experimental data. However, with that available experimental data, the developed anisole mechanism shows a good agreement predicting LBS and IDT results. The chemical kinetics of this fuel is also analyzed through reaction path flux and sensitivity analyses. Although, detail mechanisms have higher accuracy, they would be very expensive when using in multiscale computational fluid dynamics (CFD) modeling. Therefore, different mechanism reduction schemes are considered to reduce the mechanism size. Initially direct relation graph (DRG), direct relation graph with error propagation (DRGEP) and sensitivity analysis is implemented to generate a skeleton mechanism for PCRL-Mech1, which successfully reduced its size. In addition, the rate-controlled constraint equilibrium (RCCE) analysis is considered as a reduction scheme. The constraints for RCCE calculation are selected through approximate singular value decomposition of actual degree of disequilibrium (ASVDADD) analysis. A good comparison of temperature profile of RCCE simulation proves the success of ASVDADD method.

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This thesis presents a technique for the optimal synthesis of planar five-link mechanisms that produce a desired mechanical advantage function over a specified path. Since a five-bar linkage has two degrees of freedom, small deviations from the specified path are possible without significantly altering the mechanical advantage function. The research shows one potential application, the design of strength machines, where it is important to control force while allowing the user freedom of motion. In the past, closed-form analytical synthesis techniques have been used to design mechanical-advantage-generating linkages. This method is time consuming and case specific. However, optimal synthesis techniques apply to the general case and present a robust solution procedure. This thesis uses the non-linear pattern search technique of Hooke and Jeeves to synthesize five-bar linkages. The search technique matches user strength curves and mechanism resistance curves to produce a five-link mechanism. This mechanism produces the desired mechanical-advantage function and serves as the basis for strength training machines. Unlike analytical synthesis, optimization allows direct incorporation of a greater number of design constraints, thus resulting in solutions that are more practical. The pattern search technique aims to minimize a given objective function that depends primarily on the force generating capabilities and kinematic constraints on of the linkage. / Master of Science