Shah studied an MSc in Manufacturing System Engineering and worked as an engineer and consultant at Bristol-based manufacturing companies to carry out 'continuous improvement' projects. He received an MPhil in Manufacturing from the University of the West of England, Bristol. He joined the Manufacturing Metrology Team (Advanced Manufacturing Technology Research Group) of the University of Nottingham to pursue his PhD (2015-19) under the supervision of Prof. Richard Leach and Dr. Samanta Piano. His PhD project is in the field of ultra-precision engineering and he is passionate to build his specialty in this field after his study.
The rapid development of high-power lasers has opened new opportunities for large-scale laser facilities to operate at high repetition rates as opposed to their current very low repetition rates. One… read more
The rapid development of high-power lasers has opened new opportunities for large-scale laser facilities to operate at high repetition rates as opposed to their current very low repetition rates. One of the many challenges to ensure reproducible optimum interaction conditions during high repetition rate laser operations is how to position and align a target at the laser focus with an accuracy of less than a micrometre. This represents a serious problem for a high-repetition rate laser system in which a fresh target has to be positioned and aligned at the laser focus at a rate of at least 0.1 Hz. To meet the specifications for target positioning accuracy, the Central Laser Facility (CLF) has designed and developed a new solution, called as high-accuracy microtargetry system (HAMS), for accurate and precision mounting and motion control of targets for the Astra-Gemini laser. Positioning and alignment accuracy of the target using HAMS will be dependent upon a number of factors, such as the target geometry, accumulation of errors on the motion stages and tripod of HAMS (rotational and translational motion errors, errors due to wobble/ eccentricity, etc.) and the flatness tolerances on the wafer and interface wheel. Research is currently being carried out to reduce the errors propagated through the individual elements of HAMS, such that the accumulated accuracy is within the defined specification.
HAMS has a hybrid kinematic structure, which consists of parallel and serial mechanisms, and is designed to exploit the advantageous characteristics of both types of kinematic structure. The hybrid structure is a new technology and has recently received much attention. Considerable research is going on to utilise hybrid structures in industrial applications, for example, Tricept and Exechon are two commercially successful hybrid machine tools. However, comprehensive studies of their design, kinematics, dynamics and error sources are still very limited.
The focus of the current research work of the PhD is to identify the wide range of errors that can affect the performance of the hybrid structure (HAMS), which causes the deviations of the positioning and orientation accuracy of microtargets during the positioning and alignment process of laser operations. Identifying these sources of error to develop effective error compensation strategies is particularly important for high-precision applications and, as such, developing an error model, based on kinematic analysis of the structure, is of particular interest of the current work.
Developing real-time metrology of the positioning and alignment of the micro-targets for high power laser systems operating at high repetition rates.