Asian Transactions on Engineering

Volume: 01, Issue: 06, January 2012
ISSN 2221-4267


Title: Special purpose Nano-grinding Machine for Fabrication of Different Profiles on Optical Fibers Endfaces
Author: Yousef A. Gharbia
Paper ID: ATE-30101064
Pages: 1 - 9
Abstract: Optical fiber tips require to be modified in different ways to make them suitable for different applications. It has been well established in the literature that fabricating micro-lenses on optical fiber endfaces can be used to improve light coupling efficiency in optical fiber system, in optical sensors, in scanning electronic microscopy, etc. This paper looks into the feasibility of using nano-grinding technique to produce fiber tips with different profiles. The paper includes description of nano-grinding machine (NGM), determination of grinding parameters, and presents SEM and other optical microscope photographs of some samples of different profiles ground on single mode optical fibers endfaces.

Full Text: PDF (683 KB)


Title: Maintenance Practices in Cement Industry
Author: Hani Shafeek
Paper ID: ATE-70115068
Pages: 10 - 20
Abstract: This paper analyzes an existing maintenance management system in a cement factory in the Kingdom of Saudi Arabia using a modified questionnaire. The analysis shows that there are strong areas such as predictive maintenance and maintenance automation. Other areas are found weak such as training programs and maintenance reporting. Some areas are found mix between strong and weak such as maintenance documentation, and maintenance planning and scheduling. This paper is an assessment initiative for maintenance and productivity continuous improvement and can be integrated as a part of a decision support system for maintenance management.

Full Text: PDF (340 KB)


Title: A microcontroller based system to maximize extraction of solar energy
Author: Mostefa Ghassoul
Paper ID: ATE-60103067
Pages: 21 - 31
Abstract: This paper presents the design of a microchip PIC 18F452 micro controller based tracking solar energy system, where the panels could be located so that maximum solar energy could be extracted. The system is based on a small light detecting resistor mounted on a small miniature motor known as PILOT. Its role is to search for a position where maximum energy extraction could be obtained without consuming high energy. A second set represents the solar cells panels system. The panels are mounted on a bigger motor. If the energy, where the PILOT is located, is bigger than that produced by the panels, then the panels are rotated to align themselves with the PILOT position otherwise they are maintained at the current one. The main advantage of the system is that it uses a search procedure based on the PILOT scheme. The PILOT is rotated at a pre-programmed angle and at pre-determined periods using short pulses produced by the microcontroller's timers. This is done by delivering programmed pulses which drive the rotating motor carrying the PILOT through the same programmed angle. When the PILOT comes to standstill on the falling edge of the driving pulse, the voltages picked up by the two sensors mounted on the PILOT and the panels are compared. If the difference between the voltages picked by the PILOT sensor and the panel's sensor is less than the threshold, then the panels maintain their current position and the PILOT continues tracking the sun. If the difference is bigger than the threshold, then the microcontroller activates the panel's motor drive so that they align themselves with the PILOT. This is done by using a proximity switch mounted on the panels and a switch reflector mounted on the PILOT. When the proximity switch comes into the proximity of the reflector (about 3mm), it triggers the microcontroller to deactivate the panels drive, so that the panels come to a standstill after aligning themselves with the PILOT. The PILOT then waits for the next search; and it continues tracking the sun. When the system hits the end of run proximity switch, it stops and waits for sun set. When this is the case, then the system rolls forward through 180 degrees angle where the sunrise proximity switch is activated so it stops back and waits for the following morning. The choice of the PIC flash micro controller is because it could be reprogrammed on-line using the technique known as In-Circuit Serial Programming as well as its competitive price and size. It has also all the required interfaces and timers, and is very easy to program using either C language or assembly language.

Full Text: PDF (444 KB)


Title: Passive Electromagnetic Damping for Aerospace Electromechanical Actuation using PMSM
Authors: Mohsin Shahzad, Aadil Latif, Abdur Rashid and Khurram Jahangir
Paper ID: ATE-70114068
Pages: 32 - 39
Abstract: This paper presents MATLAB based design and implementation of Passive electromagnetic damping for the spoiler surface in an aircraft. The main objective is to set the parameters of damper so that the disturbances to the spoiler position can be minimized to an acceptable level hence, improving the response of the spoiler to a disturbance and also the energy flow back to the motor, its controllers and power electronic circuitry. In this paper, out of different damping techniques, passive electromagnetic damping is used to develop this model. By the end, results are compiled to show the improvement in response of the spoiler position after addition of designed passive damper.

Full Text: PDF (428 KB)