For the requirements of high-speed signal transmission has been increasing, the fiber array in the communication system has a lot of advantages which can not be replaced. But the loss of coupling efficiency is a difficult problem as the distance of communication is getting longer and longer. In order to increase the transmission and the coupling efficiency, we produce the two with high precision to reach the goal. The technique producing one dimension fiber array is very adept now. This paper chooses mounting several one dimension fiber array to produce the two dimension fiber array. Because BGA has self-alignment character, the fiber array can get nice mounting accuracy in horizontal but can¡¦t get in vertical. We use active packing to manufacture two dimension fiber. In this process we exert external force to control the mounting height. In the first, use approximate software to get the best manufacturing parameter. Then complete the experiment and compare the result with the approximation.

As magnetic computer disks are developed to ever-greater data storage densities, the accuracy required for head positioning is moving beyond the accuracy provided by present technology using single-stage voice-coil motors in hard disk drives. This thesis details work to develop a novel active suspension arm with 2-dimensional actuation for use in advanced hard disk drives. The arm developed is capable of high-bandwidth data tracking as well as precision head flying height control motion. High-bandwidth data tracking is facilitated by the use of piezoelectric stack actuator, positioned closer to the head. The suspension arm is also capable of motion in the orthogonal axis. This motion represents active flying height control to maintain the correct altitude during drive operation. To characterise the suspension arm's structural dynamics, a high-resolution measurement system based on the optical beam deflection technique has been developed. This has enabled the accurate measurement of minute end-deflections of the suspension arm in 2-dimensions, to sub-nanometre resolution above noise. The design process of the suspension arm has led into the development of novel piezoelectric-actuated arms. In the work involving lead zirconate titanate (PZT) thick films as actuators, work in this thesis shows that reinforcing the films with fibre improves the overall actuation characteristics of the thick films. This discovery benefits applications such as structural health monitoring. The final suspension arm design has been adopted because it is simple in design, easier to integrate within current hard disk drive environment and easier to fabricate in mass. Closed-loop control algorithms based on proportional, integral and derivative (PID) controller techniques have been developed and implemented to demonstrate high bandwidths that have been achieved. The suspension arm developed presents an important solution in head-positioning technology in that it offers much higher bandwidths for data tracking and flying height control; both very essential in achieving even higher data storage densities on magnetic disks at much reduced head flying heights, compared to those in existing hard disk drives.

As science and technology continue to advance, innovative developments in transportation can enhance product safety and security for the benefit and welfare of society. The federal government requires every commercial truck to be inspected before each trip. This pre-trip inspection ensures the safe mechanical condition of each vehicle before it is used. An Unmanned Aerial Vehicle (UAV) could be used to provide an automated inspection, thus reducing driver workload, inspection costs and time while increasing inspection accuracy. This thesis develops a primary component of the algorithm that is required to implement UAV pre-trip inspections for commercial trucks using an android-based application. Specifically, this thesis provides foundational work of providing stable height control in an outdoor environment using a laser sensor and an android flight control application that includes take-off, landing, throttle control, and real-time video transmission. The height algorithm developed is the core of this thesis project. Phantom 2 Vision+ uses a pressure sensor to calculate the altitude of the drone for height stabilization. However, these altitude readings do not provide the precision required for this project. Rather, the goal of autonomously controlling height with great precision necessitated the use of a laser rangefinder sensor in the development of the height control algorithm. Another major contribution from this thesis research is to extend the limited capabilities of the DJI software development kit in order to provide more sophisticated control goals without modifying the drone dynamics. The results of this project are also directly applicable to a number of additional uses of drones in the transportation industry.

In high density magnetic hard disk drives, both fast track seeking and extremely accurate positioning of the read/write head are required. A new piezoelectric microactuator with transverse and lateral control of the head positioning system for high density hard disk drives is proposed. First, the structure of the new piezoelectric microactuator is illustrated. Design of the new microactuator is based on the axial deformation of piezoelectric elements for lateral motion and the bimorph actuation of piezoelectric elements for transverse motion. Next, a mathematical model of the microactuator system is defined. Static properties associated with the displacement of the system are evaluated and then dynamic system equations of the system are evaluated. Frequency response of the system is studied based on the dynamic system equations of the actuator system. Dynamic properties of the system with a variety of system parameters are evaluated. Finally, the controller design for the actuator is presented. Simulation results show that the new actuator achieves a maximum stroke of displacement of more than 0.2m with servo bandwidth of more than 5 kHz in the lateral direction and the flying height is decreased to less than 6 nm with resonance frequency of more than 100 kHz under the 0.5 % damping assumption. The new piezoelectric microactuator improves performance of high density hard disk drives by increasing servo bandwidth and decreasing flying height.

Made available in DSpace on 2015-05-14T12:09:10Z (GMT). No. of bitstreams: 1 parte4.pdf: 2480068 bytes, checksum: 34bc2a4e8a262fe9f29d5e3768665cbb (MD5) Previous issue date: 2006-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work discusses the stepped control of building heights in three seashore districts of João Pessoa-PB, Brazil Cabo Branco, Tambaú e Manaíra , with a view to grasp the principles and concepts underlying the adoption of that instrument. The discussion of the issue required an analysis of the relations between density and the performance of the urban organism. A simulation was made to foresee the densification of a sample of Tambaú district following the present legislation and the tendencies of the property market and the impact of this densification on the local traffic was pointed out. The research has shown that the instrument in question and the other relevant legislation are not able to control effectively the local density / O presente trabalho discute a questão do gabarito escalonado em vigor na orla marítima de João Pessoa - PB (bairros do Cabo Branco, de Tambaú e de Manaíra), buscando esclarecer os princípios e conceitos que fundamentaram a adoção desse mecanismo. Para embasar a discussão do tema, analisaram-se as relações entre a densidade e o funcionamento do organismo urbano. Foi simulado um adensamento em conformidade com a legislação vigente e as tendências do mercado de um trecho do bairro de Tambaú e verificaram-se as repercussões dele no funcionamento do sistema viário. Constatou-se na pesquisa que a legislação em vigor na área sujeita ao gabarito escalonado não consegue controlar de forma eficaz a densidade local