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Mechanical Engineering Laboratory 1990 March |
| 12-1 Power Transmission System | 
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Power Transmission System The increasing use of power transmission systems in unusual environments such as those found in aviation and space applications, requires continuous improvements in performance and reliability. Many different combinations of mechanical components are found in transmission systems, and the purpose of this study is to investigate the characteristics of a typical range of component combinations in different environments, with a view to developing new methods for design and performance evaluation. Research is also under way towards the creation of integrated design systems which use the knowledge gained in this study to produce optimized mechanisms. |
| 12-2 Control of Structure-borne Noise | 
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Control of Structure-borne Noise It is well known that the vibrational modes of any structure largely determine the characteristics of the noise it emits when excited, but this type of noise generation mechanism is as yet not completely understood. This project is aimed at gaining this understanding, with a view to achieving the capability to design structures such that the balance of vibrational modes causes near-field noise cancellation thus giving a structure which is, overall, noise-free. |
| 13-1 Micro-machines | 
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Micro-machines It appears that micro-machines - which have hitherto been found only in the realm of science fiction films - may at last make an appearance in the real world, making significant contributions in fields such as genetic engineering and medical technology. Recent developments in mechanical and electronic engineering have already lead to the capability to produce components, sensors, and actuators which are so small that they are almost invisible. However, the production of micro-machines which are practically useful still requires considerable basic research on mechanisms, materials, and production techniques. This project aims to establish the new, key mechanical engineering technologies which are required to support the production of practical micro-machines. |
| 13-2 Methods for Evaluation of Ice and Snow Tires | 
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Methods for Evaluation of Ice and Snow Tires Tire performance under icy conditions is an important factor affecting vehicle dynamics in certain conditions. A test rig for evaluating the performance of tires on ice has been developed, consisting of a drum which is uniformly coated with ice on the inside. This rig is currently being used for the study of test standards, and for analysis of the mechanisms governing tire traction under icy conditions. |
| 14-1 Ceramic Rolling Bearings | 
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Ceramic Rolling Bearings Ceramic bearings which have good thermal properties, low weight, high stiffness, non-magnetism and corrosion resistance, are currently attracting much attention since they have the potential to provide solutions for several pressing engineering problems. This project is aimed at the evaluation of ceramic materials with a view to applying them in such bearings. The work also includes determination of bearing performance under high speed, high temperature conditions, and evaluation of lubricants and lubrication techniques. |
| 14-2 Wear Diagnosis and Failure Prediction for Machine Elements | 
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Wear Diagnosis and Failure Prediction for Machine Elements On-line diagnosis techniques are important tools for improving machine reliability. This project is aimed at the development of diagnosis techniques for rolling bearings and gears, using acoustic emission (AE), vibration analysis, and temperature measurement. The work has shown that AE signals can be reliably used to predict rolling fatigue failures, and a new failure-detection technique has been developed which gives four different kinds of output information by the appropriate processing of signals from only one sensor. AE techniques for the investigation of running gears are also under development. |
| 15-1 Processing under Non-equilibrium Thermal Conditions | 
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Processing under Non-equilibrium Thermal Conditions High energy ion implantation and high speed particle impact produce non-equilibrium states in materials, and can be used to make devices which have properties not achievable by conventional techniques. This research makes use of a MeV ion implanter and a particle impactor to investigate techniques for the production of this type of novel device. The ion implantor can produce ions whose energies are stable and well-determined, in the range from 50 keV to a few MeV. It is used for surface modification studies, hybrid machining, and fabrication of layered micro-mechanical components. The particle accelerator can accelerate small particles to speeds of up to several km/s, and has a new quick valve system which makes repeated operation possible. It is used for the study of shock phenomena associated with impact. |
| 15-2 Acoustic Microscopes and their Application to Materials Evaluation | 
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Acoustic Microscopes and their Application to Materials Evaluation As the requirement for materials which have good performance under extreme conditions increases, new technology is needed to evaluate their mechanical properties. This project is aimed at the development of novel scanning acoustic microscope and photoacoustic microscope for materials evaluation applications. Scanning acoustic microscope can detect flaws as small as a few micrometers. A new system is being developed where the temperature of the sample can be brought to between ambient and liquid nitrogen. At the same time the sample may also be mechanically stressed. In photoacoustic microscope the sample is irradiated with a chopped light beam and the mechanical characteristics is evaluated from the acoustic signals generated as a result of the irradiation. An extension of this method, whereby the wavelength of the light beam may be swept during the measurement to extract detailed information, is currently under development for thermal shock studies. |
