Ghulam Ishaq Khan Institute of Engineering Sciences and Technology

About: Ghulam Ishaq Khan Institute of Engineering Sciences and Technology is a education organization based out in Topi, Pakistan. It is known for research contribution in the topics: Thin film & Quantum efficiency. The organization has 618 authors who have published 940 publications receiving 10674 citations.

Fabrication and investigation of cellulose acetate-copper oxide nano-composite based humidity sensors

Abstract: Cellulose acetate-copper oxide (CA-CuO) nano-composite based smart humidity sensors have been fabricated by using instrument-less novel technology, which is being introduced first time by our group. In this technology no major instrument is involved in the fabrication process. The composites are developed by solution and mechanical mixing techniques to fabricate film and pellet type sensors, respectively. The composition and surface morphologies are analyzed by field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDS). Results of investigation show that the sensing range is from 0 to 90% relative humidity (RH) and sensing mechanism is based on change in resistance and capacitance with change in humidity. With change in humidity from 0 to 90% RH the resistance decreases by 1093 times, while the capacitance increases by 127 times. Average change in resistance and capacitance is up to 3.8 MΩ/%RH and 19.2 pF/%RH, respectively. The adsorption-desorption behavior and the consequences of measuring frequency have been discussed in detail. The fabricated sensors are attractive to develop reliable humidity meter for environmental monitoring and industrial applications.

Design, implementation and testing of electrostatic SOI MUMPs based microgripper

Abstract: This paper presents a detail modeling, finite element analysis and testing results of MEMS based electrostatically actuated microgripper. Interdigitated lateral comb pairs have been used to actuate the microgripper. The microgripper is optimized using standard SOI-MUMPs technology in L-Edit of MEMS-Pro with dual jaws actuation at low voltages. Coupled electromechanical finite element analysis performed in COVENTOR-WARE shows total displacement of 15.5 μm at jaws tip at 50 V, which is quite comparable to experimental result of 17 μm displacement at the tip of gripper jaw for the same voltage. Micromanipulation experiments have successfully demonstrated the gripping, holding micro-objects between 53 and 70 μm in size. The simulated model is used to study detail profile of Von Mises stresses and deformations in the model. It is noted that maximum stress in microgripper is 200 MPa which is much smaller than yield stress of 7 GPa. The slight difference between finite element analysis and experimental results is because of small variations in process material parameters. The total size of gripper is 5.03 × 6.5 mm2.