Taylan Das - Academia.edu (original) (raw)

Papers by Taylan Das

Volume 8: 30th Conference on Mechanical Vibration and Noise, 2018

In this study, we present triboelectric nanogenerators (TENGs) for vibrational energy harvesting ... more In this study, we present triboelectric nanogenerators (TENGs) for vibrational energy harvesting in oil pipelines. The generators are designed to replenish the batteries of leak detection sensor, thereby increasing their lifespan and reducing the need for maintenance. The TENGs were designed to harvest energy from a 12-inch diameter pipeline, vibrating with at 32 Hz. Three alternative materials were used for the upper plate of a 4 × 4 cm TENG, namely Polytetrafluoroethylene (PTFE), unstructured polydimethylsiloxane (PDMS) and structured PDMS. Tests revealed that the unstructured PDMS TENG outperformed the PTFE TENG and generated 47.6 μW of power. Structuring the PDMS by patterning open channels on half of the surface increased the output power to 200.0 μW. When the spring constant of the structured PDMS TENG was optimized, the output power was further increased to 297.7 μW. These results demonstrate that structured PDMS shows promise in triboelectric energy harvesting, specifically ...

2022 IEEE 35th International Conference on Micro Electro Mechanical Systems Conference (MEMS)

This paper presents a novel varifocal mirror made of a micro-electromechanical system (MEMS) cont... more This paper presents a novel varifocal mirror made of a micro-electromechanical system (MEMS) continuous deformable mirror (DM). It uses resonant electrostatic actuation (REA) via single voltage waveform to vary the focus of a 1.6 mm circular DM. Unlike traditional DMs, REA eliminates the need for individually addressable electrodes and the use of complex influence functions. It also minimizes the electrode count, thereby providing for simpler and faster modulating DMs. The DM was integrated into an adaptive optics system as varifocal mirror. The system was able to realize an 8 cm focal shift between focal lengths of 11 cm and 19 cm by changing the phase angle between the DM drive signal and the pulse signal of the incident laser beam.

Lecture Notes in Mechanical Engineering, 2019

Robot programming is a very significant task in the field of robotics. Off-line programming (OLP)... more Robot programming is a very significant task in the field of robotics. Off-line programming (OLP) is a method performed before robot manipulation. It is the manual editing of the robot code using computer software to simulate the real robotic scenarios. Task sequence planning, short-term production, flexibility during operation and expecting real behaviour of the robots are some of the reasons that make the users prefer OLP. Operations can be visualized in many processes such as welding, cutting, even medical applications. In this study, off-line models are offered including the forward and inverse kinematics of a six Degree-Of-Freedom (DOF) serial robot manipulator (Denso VP-6242G). Robotic Toolbox combined with GUI Development Environment in Matlab® is used for the forward kinematics solution. A Matlab® Simulink model with Simmechanics blocks is used in the inverse kinematic analysis. Visualization is enriched by 3D Solidworks® models of the robot parts. Basic motion examples that...

Journal of Sound and Vibration

Abstract Curved composite beams are the most widely preferred structures due to their high streng... more Abstract Curved composite beams are the most widely preferred structures due to their high strength, low weight, corrosion and heat resistance. The aim of this study is to examine the modalities and natural frequencies of curved cracked composite (CCC) beams under different boundary conditions. Numerical and experimental free vibration analyses of curved composite beams with transverse cracks of various depths and locations are presented. Fixed-Fixed and Fixed-Free (cantilever) boundary conditions are used for both numerical and experimental studies. It is observed that the natural frequency values of the modes decrease as the crack depth increase depend on the crack position in the material.

Proceedings of the 1998 American Control Conference. ACC (IEEE Cat. No.98CH36207), 1998

Gazi University Journal of Science

This paper presents a new approach to eliminate the residual vibration of shedding system and the... more This paper presents a new approach to eliminate the residual vibration of shedding system and the associated mechanism that connects the heddle shafts with the cam mechanisms. Effective cam design method which is based on motion design of the cam pitch curve by “blends” of the traditional profiles, formed by superimposing three functions ; a cycloid, a ramped versine, and a ramp called as ramp-plus-ramped cycloid-plus-ramped versine is proposed in this study. This function is reshaped using the system’s natural frequency and damping ratio to yield almost zero residual vibration of the heddle shaft. The proposed method is then compared with the well known cam curves and its applicability is shown by simulation and experimental results. The results show that the proposed method is quite effective for fast vibration free motion of the heald frame.

2007 22nd International International Symposium on Computer and Information Sciences, 2007

... Ref. [5] proposed a new approach for offline tracing and representation of the signatures. ..... more ... Ref. [5] proposed a new approach for offline tracing and representation of the signatures. ... [8] used Multi layer perceptron for identification and authentification of handwritten signatures with a connectionist approach. Ref. ... Ref. [15] proposed a new method of off-line SV that ...

International Journal of Biometrics, 2011

... on Pattern Recognition, Cambridge, UK. Kalera, MK, Srihari, S. and Xu, A. (2004) 'Of... more ... on Pattern Recognition, Cambridge, UK. Kalera, MK, Srihari, S. and Xu, A. (2004) 'Off-line signature verification and identification using distance statistics', Int. ... Srinivasan, H., Srihari, SN and Beal, MJ (2005) 'Signature verification using Kolmogorov Smirnov statistics', Proc. Int. ...

Engineering Applications of Artificial Intelligence, 2009

Analysis of signature is a widely used and developed area of research for personal verification. ... more Analysis of signature is a widely used and developed area of research for personal verification. A typical signature verification (SV) system generally consists of four components: data acquisition, pre-processing, feature extraction and verification. A ...

Mathematical and Computational Applications

In this study, the in plane vibrations of cracked circular curved beams is investigated. The beam... more In this study, the in plane vibrations of cracked circular curved beams is investigated. The beam is an Euler-Bernoulli beam. Only bending and extension effects are included. The curvature is in a single plane. In plane vibrations is analyzed using FEM. In the analysis, elongation, bending and rotary inertia effects are included. Four degrees of freedom for in-plane vibrations is assumed. Natural frequencies of the beam with a crack in different locations and depths are calculated using FEM. Comparisons are made for different angles.

Materials

Cellular polypropylene (PP) has been recently used in energy harvesting applications. In this wor... more Cellular polypropylene (PP) has been recently used in energy harvesting applications. In this work, we investigate its viability and long-term stability under various operating conditions. Specifically, the effect of constant stress and stress cycling on output power and long-term stability of ferroelectret energy harvesters is analyzed. Our findings show that after 112 days constant stress significantly increases the piezoelectric charge constant d 33 and output power from 0.51 μW for a stress-free harvester to 2.71 μW. It also increases the harvester center frequency from 450 to 700 Hz and decreases its optimal resistance from 7 to 5.5 M Ω .