Design of the mechanical components greatly depends on their expected structural performances. In modern design applications these performances are quantified by computer-based analysis and occasionally confirmed by experimental measurements or theoretical calculations. The dependency of the mechanical product to the structural analysis process is more significant under the product’s multi-functionality aspect that requires analyses for a variety of Variable Input Parameters, to obtain various structural responses and against more than one failure or design criterion. Structural analysis is known as the expert field, which requires an upfront investment and facilitation to be implemented in commercial design environment. On the other hand, the product design process is a systematic and sequential activity that put the designer in the central role of decision making. Lack of mutual understanding between these two disciplines reduces the efficiency of the structural analysis for design. This research aims to develop an integrated methodology to embed the structural analysis in the design process. The proposed methodology in this research combines the benefits of state-of-the-art approaches, early simulation and Validation and Verification practice, towards the specified aim. Moreover the novelty of the proposed methodology is in creative implication of Quality Function Deployment method to include the product’s multi-functionality aspect. The QFD-Based Design Integrated Structural Analysis methodology produces a reliable platform to increase the efficiency of the structural analysis process for product design purpose. The application of this methodology is examined through an industrial case-study for the telescopic cantilever boom, as it appears in Access platforms, and Cranes products. Findings of the case-study create a reliable account for the structural performance in early stages of the design, and ensure the functionality of the proposed methodology.

In this study, particle impact damping is measured for a cantilever beam with a particle-filled enclosure attached to its free end. Many particle materials are tested: lead spheres, steel spheres, glass spheres, tungsten carbide pellets, lead dust, steel dust, and sand. The effects of particle size are also investigated. Particle diameters are varied from about 0.2 mm to 3 mm. The experimental data collected is offered as a resourceful database for future development of an analytical model of particle impact damping.

In this study, particle impact damping is measured for a cantilever beam with a particle-filled enclosure attached to its free end. Many particle materials are tested: lead spheres, steel spheres, glass spheres, tungsten carbide pellets, lead dust, steel dust, and sand. The effects of particle size are also investigated. Particle diameters are varied from about 0.2 mm to 3 mm. The experimental data collected is offered as a resourceful database for future development of an analytical model of particle impact damping.

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In the field of optical fiber sensors, one of the most versatile structures is the Fabry-Perot interferometer. This thesis will present a novel sensor based on an Intrisnic Fabry-Perot Inferferometer (IFPI) cavity to measure axial acceleration, refractive index, and temperature. The sensor structure is based on previous work done by R. Wang at the Center for Photonics Technology. This work suggests its flexibility in many different roles with a sensitivity to axial acceleration of 70 pm/unit of acceleration, to refractive index of 60 nm/Refractive Index Unit, and to temperature of 7.8 pm/°C. Future work is also discussed in measuring tangential acceleration with direction using a PM fiber as the lead-in and observing the reflections on the slow and fast axes. / Master of Science

As micro-electromechanical systems (MEMS) and smart technologies have been more matured, applications for wider fields are more available. Piezoelectric materials have the property of electromechanical energy conversion, which can convert vibration energy into electrical energy. In this paper, a general concept of the piezoelectric energy conversion is first given. Then, a simple modeling design and analysis for a special transverse mode of the piezoelectric generator called mode 31 is presented. With regard to analytical method, the piezoelectric equivalent circuit model is able to illustrate the important parameters that influence the process how the piezoelectric element generates electrical energy. We may adjust unimorph voltage by controlling the deflection of cantilever beam. And the output power is taken as the indicated parameters for the generator. The energy conversion efficiency of the generator depends on the operation frequency. By using this way, the piezoelectric power generator may be widely applied to environment with both low-frequency and high-frequency vibration range.

Composite materials are widely used in demanding applications in aerospace and other industries. In order to understand the complex behaviour of the composite materials and their components, standardised test methods are used. One example is the double cantilever beam (DCB) test in which the test specimen is loaded in an opening, i.e., tensile mode. Failures in composite materials loaded compression are different from those in tension, for example, kink band or buckling-like failures can occur. In this project, several DCBs are designed and a new fixture which allows for compression testing of a DCB is developed for an existing Instron testing machine. The fixture overcomes a known problem of tensile peak causing the failure of the adhesive at the inner surfaces of the DBC by applying additional compressive loads along the outer surfaces of the DBC. The compressive forces can induce the desired kink band formation so that researchers can better study the failure mode. The conceptual development of the new DCBs and the new fixture are presented. Several prototypes of the specimens and the fixture are modelled using the three-dimensional (3D) computer-aided design software Creo Parametric 2.0.  One of the fixtures is selected to further study. The different DCB specimens are studied in order to obtain information about the kink band using 3D finite element analysis with the software programme Abaqus CAE. The selected fixture is analysed to determine if there are any areas of concern. Finally, the behaviour of the compression stress along the DCB using two pairs of forces is studied. Unfortunately, it is determined that the tensile peak experienced by the adhesive cannot be eliminated by the application of two pairs of compressive loads, one at the free end and the other in the vicinity of the tensile peak. Several suggestions are made for future work which might serve to reduce the tensile peak; e.g., the movable force couple is applied as a surface load instead of a point load. For this, the fixture will have to be modified with a new geometry, although the DCB could be the same. This will allow further work to focus on the combined behaviour of the tensile peak and the fixture.

Galloping of structures such as transmission lines and bridges is a classical aeroelastic instability that has been considered as harmful and destructive. However, there exists potential to harness useful energy from this phenomenon. The study presented in this paper focuses on harvesting wind energy that is being transferred to a galloping beam. The beam has a rigid prismatic tip body. Triangular and D-section are the two kinds of cross section of the tip body that are studied, developed and tested. Piezoelectric sheets are bonded on the top and bottom surface of elastic portion of the beam. During galloping, vibrational motion is input to the system due to aerodynamic forces acting on the tip body. This motion is converted into electrical energy by the piezoelectric (PZT) sheets. A potential application for this device is to power wireless sensor networks on outdoor structures such as bridges and buildings. The relative importance of various parameters of the system such as wind speed, material properties of the beam, electrical load, beam natural frequency and aerodynamic geometry of the tip body is discussed. A model is developed to predict the dynamic response, voltage and power results. Experimental investigations are performed on a representative device in order to verify the accuracy of the model as well as to study the feasibility of the device. A maximum output power of 1.14 mW was measured at a wind velocity of 10.5 mph. / text

Wireless sensing applications have extended into power transmission line monitoring applications. Minimal power consumption of sensor electronics have enabled kinetic energy harvesting systems to provides a means of self sustainability in the form of parasitic energy harvesting from power transmission lines. With this goal in mind, a miniature piezoelectric bimorph cantilever harvester has been developed using a magnetic tip mass which interacts with the oscillating magnetic flux surrounding power transmission wires. The focus of this thesis is develop an analytical model which can be used to optimize the amount of piezoelectric material to support sensory electronics. Special emphasis has also been placed on magnet orientation and geometry to ensure optimal magnetic flux interaction between input and output mechanisms. A single prototype harvester is designed with an arbitrary piezoelectric material length and experimentally validated at different conductor wire currents. The analytical model shows excellent agreement in frequency prediction for the prototype tested. Two damping techniques are used to experimentally extract modal damping ratios to predict peak mechanical and electrical responses at resonance frequencies. The miniature prototype design is less than 30 mm in length with only 10 mm piezoelectric material to produce a total volume of 154 10^-12 cm^3. The power output is measured at 174.1 W of power when positioned over top a 10 AWG copper conductor a distance of 6 mm with approximately 16 Amps of current passing though the conductor.