Dr. M. Amin Karami Profile

Dr. M. Amin Karami

at Univ at Buffalo

SPIE Involvement:

Author

Proceedings Article | 15 March 2018 Presentation + Paper

Nonlinear thermally buckled piezoelectric energy harvester

Mh Ansari, M. Amin Karami

Proceedings Volume 10595, 105951A (2018) https://doi.org/10.1117/12.2300899

KEYWORDS: Resistors, Heart, Biomedical optics, Beam shaping, Sensors, Safety, Microelectromechanical systems, Capacitance, Shape analysis, Energy harvesting

Read Abstract +

Proceedings Article | 15 March 2018 Presentation + Paper

Tunable bandgaps in a deployable metamaterial

Aditya Nanda, M. Amin Karami

Proceedings Volume 10595, 105952O (2018) https://doi.org/10.1117/12.2300897

KEYWORDS: Wave propagation, Finite element methods, Metamaterials, Matrices, Modulation, Signal attenuation, Digital filtering, Tunable filters, Solar cells, Beam analyzers

Read Abstract +

In this manuscript, we envision deployable structures (such as solar arrays) and origami-inspired foldable structures as metamaterials capable of tunable wave manipulation. Specifically, we present a metamaterial whose bandgaps can be modulated by changing the fold angle of adjacent panels. The repeating unit cell of the structure consists of a beam (representing a panel) and a torsional spring (representing the folding mechanism). Two important cases are considered. Firstly, the fold angle (angle between adjacent beams), Ψ, is zero and only flexural waves propagate. In the second case, the fold angle is greater than zero (Ψ > 0). This causes longitudinal and transverse vibration to be coupled. FEM models are used to validate both these analyses.

Increasing the fold angle was found to inflict profound changes to the wave transmission characteristics of the structure. In general, increasing the fold angles caused the bandwidth of bandgaps to increase significantly. For the lowest four bandgaps we found bandwidth increases of 252 %, 177 %, 230 % and 163 % respectively at Ψ = 90 deg (relative to the bandwidths at Ψ = 0). In addition, significant increase in bandwidth of the odd-numbered bandgaps occurs even at small fold angles- the bandwidth for the first and third bandgaps effectively double in size (increase by 100%) at Ψ = 20 deg relative to those at Ψ = 0. This has important ramifications in the context of tunable wave manipulation and adaptive filtering.

In addition, by expanding out the characteristic equation of transfer matrix for the straight structure, we prove that the upper band edge of the n^th bandgap will always equal the n^th simply supported natural frequency of the constituent beam. Further, we found that the ratio (EI/k_t) is an important parameter affecting the bandwidth of bandgaps. For low values of the ratio, effectively, no bandgap exists. For higher values of the ratio (EI/k_t), we obtain a relatively large bandgap over which no waves propagate. This can have important ramifications for the design of foldable structures. As an alternative to impedance-based structural health monitoring, these insights can aid in health monitoring of deployable structures by tracking the bandwidth of bandgaps which can provide important clues about the mechanical parameters of the structure.

Proceedings Article | 5 April 2017 Paper

Analyzing the frequency band gap in functionally graded materials with harmonically varying material properties

M.h. Ansari, M. Amin Karami

Proceedings Volume 10170, 101701J (2017) https://doi.org/10.1117/12.2260296

KEYWORDS: Metamaterials, Mathematical modeling, Shape analysis, Wave propagation, Modal analysis, Smart materials, Acoustics, Chemical elements, Signal attenuation, Modulation, Solids, Finite element methods

Read Abstract +

Proceedings Article | 20 April 2016 Presentation + Paper

Energy harvesting from arterial blood pressure for powering embedded brain sensors

Aditya Nanda, M. Amin Karami

Proceedings Volume 9803, 98032Z (2016) https://doi.org/10.1117/12.2219234

KEYWORDS: Sensors, Energy harvesting, Brain, Blood pressure, Modal analysis, Sensing systems, Ferroelectric polymers, Arteries, Protactinium, Resistance

Read Abstract +

Proceedings Article | 20 April 2016 Presentation + Paper

Energy harvesting from mastication forces via a smart tooth

Muath Bani-Hani, M. Amin Karami

Proceedings Volume 9803, 98030A (2016) https://doi.org/10.1117/12.2219390

KEYWORDS: Energy harvesting, Teeth, Systems modeling, Performance modeling, Smart materials, Sensor performance, Pulse generators, Sensors, Lead, Instrument modeling, Mathematical modeling, Ions, Beryllium, Bridges

Read Abstract +

Proceedings Article | 31 March 2012 Paper

Nonlinear dynamics of the bi-stable piezoelectric wind energy harvester

M. Amin Karami, J. Farmer, Daniel Inman

Proceedings Volume 8341, 83410C (2012) https://doi.org/10.1117/12.915722

KEYWORDS: Wind energy, Magnetism, Energy harvesting, Complex systems, Nonlinear dynamics, Teeth, Wind measurement, Prototyping, Beam shaping, Wind turbine technology

Read Abstract +

Proceedings Article | 26 April 2011 Paper

Linear and nonlinear energy harvesters for powering pacemakers from heart beat vibrations

M. Amin Karami, Daniel Inman

Proceedings Volume 7977, 797703 (2011) https://doi.org/10.1117/12.880168

KEYWORDS: Heart, Complex systems, Energy harvesting, Chest, Velocity measurements, Microelectromechanical systems, Magnetism, Intelligence systems, Surgery, Biomedical optics

Read Abstract +

Proceedings Article | 9 April 2010 Paper

Nonlinear hybrid energy harvesting utilizing a Piezo-magneto-elastic spring

Mohammmad Karami, Daniel Inman

Proceedings Volume 7643, 76430U (2010) https://doi.org/10.1117/12.847566

KEYWORDS: Energy harvesting, Electromagnetism, Complex systems, Oscillators, Magnetism, Resistance, Intelligence systems, Systems modeling, Chemical elements, Electromagnetic coupling

Read Abstract +

Proceedings Article | 7 April 2009 Paper

Vibration analysis of the zigzag micro-structure for energy harvesting

Mohammad Amin Karami, Daniel Inman

Proceedings Volume 7288, 728809 (2009) https://doi.org/10.1117/12.815476

KEYWORDS: Energy harvesting, Microelectromechanical systems, Vibrometry, Testing and analysis, Shape analysis, Sensors, Beam shaping, Partial differential equations, Solar energy, Composites

Read Abstract +

Showing 5 of 9 publications

Conference Committee Involvement (5)

Active and Passive Smart Structures and Integrated Systems XV

8 March 2021 | Online Only, California, United States

Active and Passive Smart Structures and Integrated Systems XIV

27 April 2020 | Online Only, California, United States

Active and Passive Smart Structures and Integrated Systems XIII

4 March 2019 | Denver, Colorado, United States

Active and Passive Smart Structures and Integrated Systems XII

5 March 2018 | Denver, Colorado, United States

Active and Passive Smart Structures and Integrated Systems XI

26 March 2017 | Portland, Oregon, United States

Keywords/Phrases

Search In:

Publication Years