Professor and Director of Robotics Program | Mechanical & Nuclear Engineering
Professor Hadimani specializes in non-invasive brain stimulation, biomagnetics, magnetocalorics and energy harvesting research.
Email: rhadimani@vcu.edu
Areas of Expertise
Transcranial Magnetic Stimulation (Tms), Piezoelectric Energy Harvesting, Magnetic Nanoparticles, Magnetocaloric Effect, Rare-Earth Magnetic Materials, Biomagnetics, Non-Invasive Brain Stimulation
Dr. Ravi Hadimani is a Professor at the Department of Mechanical and Nuclear Engineering of Virginia Commonwealth University (VCU). He is also the Director of the Robotics program at the College of Engineering of VCU. He has established a nationally and internationally recognized research program in Biomagnetics, including magnetic neuromodulation, biomagnetic nanoparticles and devices. Across his career, his scholarly output includes 126 original research papers, 17 granted and pending patents, and over 265 international conference presentations. His research has led to industrial licensing and the formation of a university spin-off company focused on neuromodulation technologies (RAM Phantoms LLC). He is an inducted senior member of the US Academy of Inventors and the Chair of the IEEE Robotics and Automation Society Richmond Chapter. He is also the Editor-in-Chief of the IEEE Magnetics Newsletter.
Prof. Hadimani has also developed a hybrid piezoelectric–photovoltaic energy harvester capable of harvesting energy from solar, wind, and rain. This work received the UK Energy Innovation Award (2011) and was featured by BBC, New Scientist, and Scientific American. He also developed and patented piezoelectric polymer fibers for energy-harvesting textiles. He served as an Associate Scientist at Ames Laboratory, a U.S. Department of Energy National Laboratory, and as an Adjunct Assistant Professor at Iowa State University. Prof. Hadimani has received several national and international honors, including VCU’s National and International Recognition Award (NIRA), the Engineer of the Year Award (2020) from the Richmond Joint Engineers’ Council, the International Young Scientist Fellowship from the National Natural Science Foundation of China (2013), and the UK Energy Innovation Award (2011). He was recently inducted as a senior member of the U.S. National Academy of Inventors.
Accomplishments
Engineer of the Year 2020
2020-02-19
2020 Engineer of the Year awarded by Richmond Joint Engineers' Council.
Finalist British Council Alumni Award 2018
2018-01-28
One of the finalists for British Council's 2018 "Study UK" Alumni Award. https://www.britishcouncil.us/study-uk/alumni-awards
Outreach Award
2015-02-28
Received the Outreach Award by the American Physical Society, GMAG topical group.
International Young Scientist Award
2012-12-31
Recipient of the International Young Scientist Award from the National Natural Science Foundation, China (NSFC).
Energy Innovation Award
2010-12-31
Recipient of the Energy Innovation Award by the UK Energy Innovation Centre for the development of hybrid photovoltaic-piezoelectric cell that can harvest electrical energy from sun, wind and rain.
Affiliations
IEEE, (Magnetics Society, Engineering in Medicine and Biology)
American Physical Society (GMAG and Medical Physics)
“It is the perfect example of how students can get interested in something and start their own company,” said Ravi L. Hadimani, an assistant professor of mechanical and nuclear engineering at VCU who taught Beiro mechatronics and advised him on his independent studies project.
With the ever-increasing need for energy, more non-conventional energy harvesting techniques are needed. Energy can be harvested from wind, rain and other sources of mechanical energy using piezoelectric material devices. Polymer piezoelectric films have shown to produce higher energy compared to the classical ceramic piezoelectric materials from wind and rain. I was the primary researcher of a team that invented a hybrid piezoelectric and photoelectric energy harvester which was capable of harvesting energy from sun, wind and rain. This invention was awarded the UK Energy Innovation Award in 2011 which was published in various news articles such as BBC, New Scientist, Scientific America, etc. I have also developed and patented piezoelectric polymer fiber that can be weaved or knitted into energy harvesting fabric. The piezoelectric films can also act as substrates for photovoltaic cells and generate power using wind and rain energy in the absence of solar energy. I have developed and patented a hybrid photovoltaic and piezoelectric energy harvesting device that can continually harvest energy from multiple natural sources of energy such as sun, wind and rain. Our long term goal in Piezoelectric Energy Harvesting field is to improve the polarization of PVDF fiber and to develop a fully functional garment that is capable of harvesting energy from wind and other mechanical vibrations.
We are interested in developing thin films of rare-earth magnetocaloric and magnetoelastic materials. Thin films of magnetocaloric materials have the potential to be used in cooling the integrated circuits that can reduce the heating effects in high density microchips. Magnetocaloric thin films can also be used in various MEMS applications and in the read head in hard disk drives to lower the temperature of the magnetic heads and thus increase the saturation magnetization above the current limit of 2.4 tesla. Fabrication of thin films of these materials are best achieved by femto second pulsed laser deposition (PLD). In the development of these thin films by femto second PLD, various unknown meta-stable magnetic phases have been observed. These phases need to be identified and characterized. The properties of these phases can be tailored to enhance the magnetocaloric effect and magnetoelastic effect by PLD parameters. Classical characterization techniques such as EDS and XRD fail to determine the accurate composition and crystal structure of the films. Advanced techniques such as Auger Spectroscopy and TEM should be used to analyze these films.
Magnetic nanoparticles have gained tremendous attention due to their ability to navigate through the body and vary the physical properties of the tissues of interest. We have designed a technique to produce gadolinium based nanoparticles that are ferromagnetic at room temperature which can increase the MRI quality significantly. These particles can also be used in hyperthermia and targeted drug delivery
Transcranial Magnetic Stimulation (TMS) is promising neuromodulation technique which alters the neuronal functions when time-varying short pulses of the magnetic field induce an electric field in the brain. This has been used to treat depression and is currently FDA approved. Commercial TMS coils produce non-focused cortical stimulation, however, many neurological disorders such as Parkinson’s disease and Post-Traumatic Stress Disorder (PTSD) originate from deeper regions middle of the brain. In deep-brain stimulation, accurate calculation of electric field requires detailed information about the structure and electrical properties of various tissues in the brain. This calculation of electric field in the brain is normally done with a homogeneous head model which is not adequately realistic.
Research Grants
IRES: US/UK Multidisciplinary Collaboration in Magnetics
National Science Foundation 2014-04-30 RES: US/UK Multidisciplinary Collaboration in Magnetics
BT3-Biological Technologies-Life Sciences Research Tool
National Science Foundation 2016-05-31 It is an STTR grant from NSF in collaboration with National Standards and Technology (NIST)
On-chip studies of neuron cells under magnetic field stimulation
National Science Foundation 2016-05-31 On-chip studies of neuron cells under magnetic field stimulation
Optimization of thermal spray coating using sensors: magnetic
Commonwealth Center for Advanced Manufacturing 2016-09-30 Optimization of thermal spray coating using sensors: magnetic
American Institute of Physics Advances (AIP Advances) 2017-01-03
Self-polarized Gd5Si4-polyvinylidene fluoride (PVDF) nanocomposite films have been synthesized via a facile phase-inversion technique. For the 5 wt% Gd5Si4-PVDF films, the enhancement of the piezoelectric β-phase and crystallinity are confirmed using Fourier transform infrared (FTIR) spectroscopy (phase fraction, Fβ, of 81% as compared to 49% for pristine PVDF) and differential scanning calorimetry (crystallinity, ∆Xc, of 58% as compared to 46% for pristine PVDF), respectively. The Gd5Si4 magnetic nanoparticles, prepared using high-energy ball milling were characterized using Dynamic Light Scattering and Vibrating Sample Magnetometry (VSM) to reveal a particle size of ∼470 nm with a high magnetization of 11 emu/g. The VSM analysis of free-standing Gd5Si4-PVDF films revealed that while the pristine PVDF membrane shows weak diamagnetic behavior, the Gd5Si4-PVDF films loaded at 2.5 wt% and 5 wt% Gd5Si4 show enhanced ferromagnetic behavior with paramagnetic contribution from Gd5Si3 phase. The interfacial interactions between Gd5Si4 and PVDF results in the preferential crystallization of the β-phase as con-firmed via the shift in the CH2 asymmetric and symmetric stretching vibrations in the FTIR. These results confirm the magnetic Gd5Si4 nanoparticles embedded in the PVDF membrane lead to an increased β-phase fraction, which paves the way for future efficient energy harvesting applications using a combination of magnetic and piezoelectric effects.
American Institute of Physics Advances (AIP Advances) 2017-01-10
Transcranial Magnetic Stimulation is an emerging non-invasive treatment for depres- sion, Parkinson’s disease, and a variety of other neurological disorders. Many Parkin- son’s patients receive the treatment known as Deep Brain Stimulation, but often require additional therapy for speech and swallowing impairment. Transcranial Mag- netic Stimulation has been explored as a possible treatment by stimulating the mouth motor area of the brain. We have calculated induced electric field, magnetic field, and temperature distributions in the brain using finite element analysis and anatom- ically realistic heterogeneous head models fitted with Deep Brain Stimulation leads. A Figure of 8 coil, current of 5000 A, and frequency of 2.5 kHz are used as simula- tion parameters. Results suggest that Deep Brain Stimulation leads cause surrounding tissues to experience slightly increased E-field (∆Emax =30 V/m), but not exceed- ing the nominal values induced in brain tissue by Transcranial Magnetic Stimulation without leads (215 V/m). The maximum temperature in the brain tissues surround- ing leads did not change significantly from the normal human body temperature of 37 ◦C. Therefore, we ascertain that Transcranial Magnetic Stimulation in the mouth motor area may stimulate brain tissue surrounding Deep Brain Stimulation leads, but will not cause tissue damage.
