News

How do our fingertips vibrate? DigiTip can answer! 01 July 2021

Our article “Free and Forced Vibration Modes of the Human Fingertip” has recently been published in Applied Sciences. In this study, we developed DigiTip, a detailed three-dimensional finite element model of a representative human fingertip that is based on prior anatomical and biomechanical studies. Using this model, we first performed modal analyses to determine the free vibration modes with associated frequencies up to about 250 Hz. Subsequently, we applied distributed harmonic forces at the fingerprint centroid in three principal directions to predict forced vibration responses through frequency-response analyses. The results illuminate the dynamic behavior of the human fingertip in haptic interactions involving oscillating stimuli, such as textures and vibratory alerts, and they show how the modal information can predict the forced vibration responses of the soft tissue.
Link to the article

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Another journal article published in Materials 15 June 2021

My article “Design of circular composite cylinders for optimal natural frequencies” has recently been published in Materials. This study concerns optimizing the eigenfrequencies of circular composite cylinders using lamination parameters. In the lamination parameter plane, novel response contours are obtained for the first and second natural frequencies as well as their difference. The lamination parameters yielding the maximum response values are determined, and the first two mode shapes are shown for the optimum points. The results demonstrate that the maximum fundamental frequency points of the laminated cylinders mostly lie at the inner lamination parameter domain, unlike the singly curved composite panels. In addition, the second eigenfrequency shows a nonconvex response surface containing multiple local maxima for several cases. Moreover, the frequency difference contours appear as highly irregular, which is unconventional for free vibration responses.
Link to the article

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Let’s make things COMPACT! 05 June 2021

My article “COMPACT: Concurrent or Ordered Matrix-based Packing Arrangement Computation Technique” has been published in Applied Sciences. The method presented in this study allows the objects to be rotated by arbitrary angles, unlike the right-angled rotation restrictions imposed in many existing packing optimization studies based on raster methods. The raster approximations are obtained through loop-free operations that improve efficiency. Additionally, a novel performance metric is introduced, which favors efficient filling of the available space by maximizing the overall contact within the domain. Moreover, the objective functions are exploited to discard the overlap and overflow constraints and enable the use of unconstrained optimization methods. The results of the case studies demonstrate the effectiveness of the proposed technique.
Link to the article

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New journal article has been published in Materials 15 May 2021

I am glad to share that my article “Concurrent lamination and tapering optimization of cantilever composite plates under shear” has been published in Materials. In this study, I focused on simultaneously optimizing layer and taper angles of cantilever composite laminates under shear. Such an approach fully utilizes stiffness tailoring and geometric design to maximize the operational performance of the structure.
Link to the article

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Honored to be on shellbuckling.com 04 January 2021

I am proud to share that my profile is now on shellbuckling.com, a website featuring developments regarding buckling of shell structures as well as the people who substantially contributed to the field.
Link to my page

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Our journal article has been published in Computers & Structures 15 October 2020

I am happy to share that our article “Dynamic analysis of doubly curved composite panels using lamination parameters and spectral-Tchebychev method” has been published in Computers & Structures. In this paper, we built a modeling framework for the dynamic analysis of doubly curved composite panels. The proposed framework combines the computational efficiency advantages of both lamination parameters formulation and spectral-Tchebychev method. Besides the developed methodology, our novel results give insight on the optimal dynamic design of doubly curved shells.
Link to the article

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Our ICRA 2020 paper is now online 15 September 2020

Our paper “Calibrating a Soft ERT-Based Tactile Sensor with a Multiphysics Model and Sim-to-real Transfer Learning” has been published in the proceedings of 2020 IEEE International Conference on Robotics and Automation (ICRA). In this study we introduced a new method for calibrating soft ERT-based tactile sensors using sim-to-real transfer learning with a finite element multiphysics model. The model is composed of three simple models that together map contact pressure distributions to voltage measurements. We optimized the model parameters to reduce the gap between the simulation and reality. Our results show that the developed calibration technique can be utilized for improving the sensing performance of ERT-based tactile sensors.
Link to the article

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Presented two work-in-progress posters in EuroHaptics 2020 10 September 2020

EuroHaptics 2020, the primary European meeting for researchers working on haptic perception and technology, took place on September 6-9, in Leiden, Netherlands. Due to COVID-19 pandemic, the conference organizers hybridized an in-person meeting with a virtual event. I found the opportunity to present two work-in-progress (WIP) posters that contain a part of our research that we have been conducting in the Max Planck Institute for Intelligent Systems. The conference was very succesful as it enabled exchange of ideas between researchers of the field and paved the way for potential collaborations.

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New journal article has been published in Composite Structures 27 March 2020

I am glad to share that our article “Unifying lamination parameters with spectral-Tchebychev method for variable-stiffness composite plate design” has been published in Composite Structures. In this study we developed an effective framework for the analysis and optimization of the variable-stiffness composite plates. We exploited computational advantages of lamination parameter interpolation method and spectral-Tchebyshev technique to obtain a very efficient design tool.
Link to the article

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A Visit to Fethiye Science High School 03 March 2020

Today, Yasemin Vardar and I visited Fethiye Science High School to speak with the students about possible career paths in engineering and science. Impressed by the excellent questions that have been asked, we are convinced that a very bright generation is approaching!

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Our journal article got published in Materials & Design 03 June 2019

I am happy to say that our article “Multi-objective optimization of composite plates using lamination parameters” has been published in Materials & Design. In this study we investigated multi-objective optimization of composite plates using lamination parameters. We aimed to provide insight on the conformity/conflict of multiple performance metrics by determining Pareto-optimal solutions for different problem cases.
Link to the article

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Presented work-in-progress poster at World Haptics Conference 2019 11 July 2019

I presented our work-in-progress poster entitled “High-Fidelity Multiphysics Finite Element Modeling of Finger-Surface Interactions with Tactile Feedback” at World Haptics Conference 2019 held in Tokyo, Japan. The diversity and quality of the studies demonstrated in the conference were absolutely fantastic!

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