FALL 2023 seminar


8/25, Dr. Dung-An Wang

National Chung Hsing University, Taiwan

Applications of Compliant Mechanisms

11 am on 8/25


Steinman Hall Room 254

https://ccny.zoom.us/j/81357159148?pwd=Ym1maGRUeURDeTN3Y3RZOThaNUg0dz09


ABSTRACT

Compliant mechanisms with versatile configurations have applications in robotics, automatic machinery, biology, and medical devices.  The compliant mechanisms can be 3 dimensional or less depending on their working scenarios.  In this talk, we focus on planar compliant mechanisms composed of linkage type mechanisms and multistable mechanisms.  Design concepts and modelling methods will be presented.  Mostly, bistability is exploited in my work.  I also focus the beam constraint modelling method for proof of concept and feasibility investigation.  Possible applications in various fields are open and evolutions of the planar compliant mechanisms with genes from origami mechanisms will be introduced in the talk.

BIO

Dung-An Wang received the B.S. degree with high honors in mechanical engineering from the National Sun-Yet Sen University, Kaohsiung, Taiwan in 1992. He received the M.S. in mechanical engineering from the National Taiwan University, Taipei, Taiwan in 1996 and the Ph.D. degree in mechanical engineering from the University of Michigan at Ann Arbor, United States in 2004. While studying the Ph.D. degree, he joined National Steel, Michigan, United States, working on sheet metal forming. For his graduate work in University of Michigan, he specializing in MEMS, sheet metal forming and plasticity, with a dissertation on plastic and fracture analysis of engineering materials and welded structures. From 2004 to 2005, he worked at Da-Yeh University, ChangHua, Taiwan developing micromachined piezoelectric actuators and friction stir welding technologies. From 2005, he has been with National Chung Hsing University, Taichung, Taiwan, performing R&D on compliant mechanism design, novel ultrasonic horn design, steel leveling, micromachined energy harvesters and CMOS MEMS sensors and actuators. He is presently a distinguished professor in the National Chung Hsing University and a visiting professor in the Industrial University of Ho Chi Minh City, Vietnam. He in an inventor on several patents and has authored or coauthored a number of papers and a book chapter related to failure mechanisms of advanced welding processes.

9/7, Dr. Simiao Niu

Rutgers University

Wireless Bioelectric Network for Chronic Disease Management

2 pm on 9/7

Steinman Hall Room 254


ABSTRACT

60% of the world population live with at least one chronic disease. These diseases and associated comorbidities are now the leading causes of death. Effective management of complex chronic diseases requires body-wide, long-term, accurate, and continuous monitoring of multiple physiological signals from wearable devices to precisely determine the pathological state. These wearable physiological signal monitoring can dramatically reduce the demand of physician visiting and increase patients’ engagement and treatment adherence rate. Although wearable bioelectronic devices have shown huge potential in chronic disease management, existing technology still mostly relies on rigid chip components, where the interface between chips and skin/tissue has been a bottleneck that limits the system performance (noise, robustness etc). To address these challenges, my group's research has been involved in the exploration of rational system design concepts, material and device fabrication innovation, and tailored algorithms to enable a closed-loop wireless bioelectronic network that targets next-generation chronic disease management.

In this talk, I will discuss my group's efforts in building this technology platform. First, I will describe a body area sensor network technology platform. In the system design concept side, this technology utilizes a novel wireless hybridization strategy and an unconventional detuned RFID working regime that provide an ideal skin interface. In the material/device side, this system integrates several skin-conforming polymer-based soft devices (ring oscillators, RF diodes, antennas, transistors etc.) as an integrated soft multimode sensing sticker. Next, I will introduce a wireless closed-loop smart bandage that can accelerate and monitor the wound healing process with a low-impedance, high-toughness, and tunable adhesion hydrogel as skin interface. Finally, I will switch the topic to triboelectric nanogenerator, an emerging technology for mechanical energy harvesting, to provide alternative power supply for the on-body network. Overall, the developed technology platform could assess multiple health outcomes and treatment responses to various chronic diseases. Ultimately, this technology will help to reduce chronic disease burden, lower medical costs, and provide a better quality of life for patients.

BIO

Dr. Simiao Niu is an assistant professor at the Department of Biomedical Engineering, Rutgers University. Before Rutgers, he was a hardware system engineer at the health technology team in Apple Inc. He received his postdoctoral training in the Department of Chemical Engineering, Stanford University, under the supervision of Prof. Zhenan Bao, and received his Ph.D. degree in the School of Materials Science and Engineering at the Georgia Institute of Technology in 2016, under the supervision of Prof. Zhong Lin Wang. Dr. Niu earned his master of science degree in Electrical and Computer Engineering at the Georgia Institute of Technology in 2015 and his bachelor of engineering degree in the Institute of Microelectronics at Tsinghua University in 2011 with the highest honors and outstanding undergraduate thesis award. Dr. Niu's past research on wearable technology and bioelectronics has led to multiple awards, including the 2020 - 2022 Clarivate Web of Science Cross-Field Highly Cited Researcher, the 36th Japan Telecommunications Advancement Foundation Award, Research.com 2022 Rising Star of Science Award, Apple Special Recognition Award, and the MRS graduate student award. His current work focuses on wearable devices and energy harvesting systems for biomedical applications.

9/21, Dr. Paolo celli

Stony Brook University

Load Bearing, Shape-retaining Morphing Structures

2 pm on 9/21

Steinman Hall Room 254


ABSTRACT

Shape-morphing systems are designed to predictably achieve large shape changes in response to applied loads. Their applications range from everyday objects like foldable chairs, to drug delivery capsules and to temporary civil structures and deployable space structures. This talk will showcase some of our current activities in this context.

Our first objective is to answer the curiosity-driven question of finding a simple strategy to design flat sheets that can be transformed into 3D surfaces with non-zero Gaussian curvature. After illustrating a method to achieve this goal via frustrated mechanisms, I will present the subsequent steps we took to try and bridge the gap between a strategy that is only bound to work at the tabletop scale using rubbery materials, and larger-scale structural applications. Then, we will illustrate how to create morphing structures that can retain their morphed shape via localized snap-through buckling and without the need for external anchoring. Finally, we will hint at the possibility of creating locally snapping structures that display a dependence of their final shape on the snapping sequence.


BIO

Paolo Celli is an Assistant Professor in the Department of Civil Engineering at Stony Brook University. His research involves experimental and computational aspects of solid and structural mechanics, structural dynamics, and wave physics. His current interests are in the areas of i) shape-morphing and deployable structures, ii) structures with time-varying properties, iii) structures for renewable energy and iv) robotics applications. Prior to joining SBU in January 2020, he was a postdoc in mechanical and civil engineering at Caltech. Trained as a mechanical engineer in Italy, he obtained his PhD in civil engineering from the University of Minnesota in 2017.


9/28, Dr. Inigo Sanz-Pena 

City College of New York

Biomimetic wearable assistive devices with embedded sensing capabilities

2 pm on 9/28

Steinman Hall Room 254


ABSTRACT

Dr. Sanz-Pena’s research focuses on developing wearable assistive robots and orthotics with embedded sensing capabilities for healthcare applications to increase biofeedback monitoring capabilities and improve the quality of life. His approach is the implementation of metamaterials in the components of biomechatronic devices using additive manufacturing and computational design. He is currently working on modular additively manufactured wearable robots to improve biomimicry and personalization and increase the proprioception of exoskeletons. As part of this effort, he is focusing on embedding pressure and motion sensing in the material and structural properties of robots using piezoresistive elements and parametric design of architected materials.


BIO

Dr. I. Sanz-Pena is a Postdoctoral Research Associate at the Rehabilitation Robotics Laboratory at the University of Illinois at Chicago, Department of Mechanical and Industrial Engineering. He received his Ph.D. with Summa Cum Laude honors from Universidad de La Rioja, Spain, in collaboration with New York University (NYU) and held post-doctoral appointments at Imperial College London at the Biomechanics Group. He was a Research Associate at the NYU Langone Orthopedic Hospital and a project engineer at Biele Group.

10/5, Dr. Bo Wang

City College of New York

Robust Control of Heterogeneous Underactuated Vehicle Networks in Uncertain Environments

2 pm on 10/5

Steinman Hall Room 254


ABSTRACT

Heterogeneous networks are multi-agent systems that contain different dynamical models. A multi-vehicle system usually contains different types of vehicles that may possess different parameters and dynamics. For instance, a combination of ground, marine, and aerial vehicles can be used for military operations to increase the striking force from multiple sources. Nevertheless, efforts to develop cooperative control approaches applicable to heterogeneous multi-vehicle systems have been limited. Moreover, nonholonomicity and underactuation are two main obstacles in the control design for multi-vehicle systems. The problem of cooperative control of underactuated networks is far more complicated than control of fully-actuated networks.

This talk is devoted to introducing several distributed control approaches that are applicable to multi-vehicle systems. We shall present the following problems for heterogeneous underactuated and nonholonomic multi-vehicle systems:

1)  Robust formation control. By exploiting the structural properties of the planar vehicle model, a robust formation control framework is proposed for planar underactuated vehicle networks.

2) Formation stabilization and tracking control. A time-varying control strategy is presented to solve the simultaneous formation stabilization and tracking control problem for planar vehicles based on persistency of excitation.

3) Source seeking control. We propose a source seeking scheme for generic force-controlled underactuated vehicles by surge force tuning. The controller requires only real-time measurements of the source signal and ensures practical stability with respect to the linear motion coordinates for the closed-loop system.

In addition to the above theoretical analysis and control designs, we also apply these theoretical tools to real vehicle systems, including nonholonomic mobile robots, underactuated surface vessels, and quadcopters, to validate our control algorithms.


BIO

Bo Wang is an Assistant Professor of Mechanical Engineering at the City College of New York. He received the Master of Science (MSc.) degree in Control Theory and Engineering from the University of Chinese Academy of Sciences, China, in 2018, and the Ph.D. degree in Mechanical Engineering from Villanova University in 2022. After receiving his Ph.D., he was a postdoctoral fellow at the University of Illinois Urbana-Champaign. His research interests include nonlinear control theory (robust, adaptive, and passive), underactuated systems, nonholonomic systems, geometric control theory, networked control systems, extremum seeking control, learning-based control, and robotics.

10/12, Dr. Jorge Ahumada

University of Maryland Baltimore County

Coupling of Evaporative and Electrodynamic Effects on Charged Droplets of Pure and Nanofluids

2 pm on 10/12

Steinman Hall Room 254


ABSTRACT

The use of nanofluids is an attractive alternative for the pressing need to shift toward more energy-efficient hydrocarbon fuels. During the vaporization of nanofluid droplets, the particles are carried from the suspension into the liquid-gas interfacial zone where the properties of the nanomaterial can be exploited. A parametric study is presented in which shell size, time to shell formation, and the quantitative deviation from the -law are investigated as a function of initial particle concentration and Péclet number. Experimentally, single, isolated droplets are generated using the dripping mode of electrospray  (ES) and captured by an electrodynamic balance (EDB) to freely levitate during their evaporative lifetime. The effects of the charges on the liquid and gas phases are studied. In particular these effects are coupled with the hygroscopy of short-chained alcohols and presented as a function of ambient relative humidity. Electrically charged droplets are susceptible to Coulombic fissions (CF), a mechanism for secondary atomization through which charges (and a small fraction of mass) are released upon reaching a charge limit (known as Rayleigh limit). CF in evaporating water droplets and water/alumina nanofluid droplets (NFD) were studied. It is of interest to investigate the dynamics of CF in NFD, which are expected to vary with time as the particle concentration increases and the fluid properties change. High-speed imagery was used to measure the droplet diameter and its deformations during CF.


11/2, Dr. Joo H. Kim

New York University


Toward Biped Robots Walking Like Humans:

Stability and Efficienty Perspectives

2 pm

Steinman Hall Room 254


ABSTRACT

Stability and efficiency are two main performance measures for legged locomotion.  Quantitative models of these measures are critical in design and control of biped robots.  In this talk, rigorous mathematical models of robot balance stability and energy efficiency will be introduced.  The balance stability of a biped robot is quantified by partitioning an augmented state space of center-of-mass position and velocity.  Based on comprehensive definitions of the states of balance, the partitions are provided by the boundaries of balanced, capturable, and falling states of a biped robot.  Whole-body system dynamics with distributed contacts is established and integrated into optimization problems, in which the effects of multi-level momentum and stepping strategies are incorporated.  For energy efficiency, energy consumption of a robot is derived in terms of state variables, control inputs, and system parameters.  The model forms are derived theoretically using the switched electromechanical dynamics of a servomotor, while their characteristic parameters are estimated from experiments.  The predictive model can accurately evaluate instantaneous energy consumption rate without limitations inherent in experimental measurements or other approximation methods.  These models are demonstrated with robot walking experiments along with their comparative analyses against human walking.  Finally, some preliminary ideas of on-going work on formalizing the stability-efficiency trade-off relationships in bipedal walking and their potential use in benchmarking human gait for advanced design and control of walking robots will be discussed. 

BIO

Dr. Joo H. Kim is an Associate Professor in the Department of Mechanical and Aerospace Engineering at New York University (NYU) and affiliated faculty of NYU’s Center for Urban Science and Progress (CUSP).  Dr. Kim directs the Applied Dynamics and Optimization Laboratory for the broad areas of dynamics, control, and optimization of mechanical systems.  With applications in robotic and biomechanical systems and their intersections, such as wearable robots, his current research topics include the energetics of dynamic systems, legged balance and gait stability, and integration of dynamics/control with numerical optimization.  Dr. Kim received a Ph.D. degree in mechanical engineering in 2006, and M.S. degrees in mathematics, mechanical engineering, and biomedical engineering, all from the University of Iowa, and a B.S. degree in mechanical engineering from Korea University, Seoul, South Korea.  He is a member (elected) of the ASME Mechanisms and Robotics Technical Committee and a Senior Member of IEEE.  His current and past roles as an Associate Editor include the ASME Journal of Mechanical Design, the ASME Journal of Mechanisms and Robotics, and the Conference Editorial Board of the IEEE Robotics and Automation Society.  Dr. Kim is the recipient of several awards and honors, including the 2007 Top Government Technology of the Year Award from the State of Iowa, the 2014 Advanced Modeling and Simulation Best Paper Award from the ASME Computers and Information in Engineering Division, the 2015 Freudenstein/General Motors Young Investigator Award from the ASME Design Engineering Division, and the 2020 Associate Editor Award from the ASME Journal of Mechanical Design. 

11/9, Dr. George Moutsanidis

Stony Brook University


Recent Advances in Particle-based Numerical Methods for Extreme Events Modeling

2 pm on 11/9


Steinman Hall Room 254


ABSTRACT

Particle-based numerical methods, such as Smoothed Particle Hydrodynamics (SPH) and the Material Point Method (MPM), are increasingly gaining recognition within the engineering community. They offer notable advantages in representing substantial solid deformations, extreme material distortion, and free-surface flows. However, when compared to well-established mesh-based numerical techniques like the finite element method, particle-based approaches still face certain challenges. These include issues related to higher-order convergence, addressing incompressible materials, and effectively modeling damage and fracture. In this presentation, we will highlight recent advances in SPH and MPM aimed at mitigating the aforementioned limitations. Our primary objective is to enhance their capabilities for simulating extreme events, particularly in the context of scenarios like air-blast-structure interaction and coastal fluid-structure interaction.


BIO

Dr. George Moutsanidis is an Assistant Professor in the Department of Civil Engineering at Stony Brook University. He completed his PhD in Structural Engineering and Computational Science at University of California San Diego in 2018. Prior to that, he obtained an MS degree in Civil Engineering from the University of Texas at Austin and a B.Sc. in Civil Engineering from Aristotle University of Thessaloniki. Before joining Stony Brook University, he worked as a Postdoctoral Research Associate at Brown University’s School of Engineering. His research interests lie in the general areas of computational mechanics, engineering, and sciences, and he works on the development of high-performance, high-fidelity computational methods for the simulation of extreme events, such as air-blast-structure interaction, fluid-structure interaction, hypervelocity impact, and fracture. He has also been largely involved with the improvement of several state-of-the-art computational techniques including the Finite Element Method, Isogeometric Analysis, Smoothed Particle Hydrodynamics, Material Point Method, Reproducing Kernel Particle Methods, and Peridynamics.

Joint ME/Levich Seminar

11/16, Dr. Timm Krueger

University of Edinburgh

Particle Pairs and Suspensions in Inertial Microfluidics - Insights from Computer Simulations

ABSTRACT

Inertial particle microfluidics is a relatively new technology that exploits inertial effects to manipulate and control particle dynamics. Under inertial flow conditions, particle-particle interactions can lead to the formation of pairs and trains of particles. We analyse the behaviour of two and multiple capsules in channel flow under moderate inertia. We employ an immersed-boundary-lattice-Boltzmann-finite-element solver to account for the fluid mechanics, the capsule dynamics, and their coupling. We find that the formation of stable pairs of particles depends on the relative size and softness of the particles and their positions at the time of their first encounter. Suspensions with more particles show shear-induced fluctuations that compete with inertial focussing. Applications relying on lateral focussing, such as separation, or precise inter-particle spacing, such as cytometry, might benefit from our findings.

 

BIO

My research group is interested in understanding the dynamics of cellular blood flow in the microcirculation and in microfluidic devices, in particular in inertial microfluidics. We are using computer simulations to explore fundamental mechanisms and answer questions related to biological problems.

 

2008-2011: PhD in Physics at Max Planck Institute in Dusseldorf and Ruhr University Bochum, Germany

2011-2012: Postdoc in Applied Physics at Technical University Eindhoven, Netherlands

2012-2013: Postdoc in Chemistry at University College London, UK

2013-2018: Chancellor’s Fellow at University of Edinburgh, UK

2018-2020: Lecturer (Assistant Professor) in Chemical Engineering at University of Edinburgh, UK

2020-2023: Reader (Associate Professor) in Chemical Engineering at University of Edinburgh, UK

Since 2023: Professor of Fluid and Suspension Dynamics at University of Edinburgh, UK