Remotely Moving Objects Underwater Using Sound #ASA188

Remotely Moving Objects Underwater Using Sound #ASA188

Acoustic metamaterial enables pushing, rotating, and more complex movements in 3D.

Media Contact:
AIP Media
301-209-3090
media@aip.org

NEW ORLEANS, May 20, 2025 – Sound can do more than just provide a nice beat. Sound waves have been used for everything from mapping the seafloor to breaking apart kidney stones. Thanks to a unique material structure, researchers can now move and position objects underwater without ever touching them directly.

Dajun Zhang, a doctoral student at the University of Wisconsin-Madison, will present his work on developing a metamaterial for underwater acoustic manipulation Tuesday, May 20, at 3:20 p.m. CT as part of the joint 188th Meeting of the Acoustical Society of America and 25th International Congress on Acoustics, running May 18-23.

metamaterial

The metamaterial created by Zhang is used to push and rotate an object adorned with the University of Wisconsin’s Bucky the Badger. Credit: Dajun Zhang

A metamaterial is a composite material that exhibits unique properties due to its structure. Zhang’s metamaterial features a small sawtooth pattern on its surface, which allows adjacent speakers to exert different forces on the material based on how the sound waves reflect off it. By carefully targeting the floating or submerged metamaterial with precise sound waves, Zhang can push and rotate any object attached to it exactly as much as he wants.

Manipulating objects in water without touching them could make a lot of underwater work easier. It could also be used inside the human body, which is mostly water, for applications like remote surgery or drug delivery.

“Our metamaterial offers a method to apply different acoustic radiation forces on objects in liquid media, such as underwater robots and vehicles, parts for assembly, or medical devices and drugs,” said Zhang.

However, manufacturing underwater metamaterials with the correct properties for object manipulation is difficult, especially with conventional methods.

“Current fabrication methods for underwater metamaterials do not provide the resolution or material properties required and are usually very expensive,” said Zhang. “To solve this issue, I developed a new fabrication method. This method is not only low cost and easy to implement but also achieves high fabrication resolution and large acoustic impedance contrast with water, which are keys to underwater metamaterials.”

In tests, Zhang used his metamaterial to manipulate floating objects, such as wood, wax, and plastic foam, along with objects completely submerged underwater. He attached his metamaterial to each object and used acoustic waves to push, pull, and rotate them. With submerged objects, this technique gave him the ability to manipulate them in three dimensions.

Zhang plans to continue his work, developing a metamaterial patch that is smaller and more flexible. He hopes his work will lead to new uses in medicine and underwater robotics.

“Our research opens new opportunities for both underwater acoustic metamaterials and remote manipulation,” said Zhang. “Acoustic metamaterials and metasurfaces can now be used to generate forces remotely for underwater or in-body levitation, actuation, and manipulation applications.”

——————— MORE MEETING INFORMATION ———————
Main Meeting Website: https://acousticalsociety.org/new-orleans-2025/
Technical Program: https://eppro01.ativ.me/src/EventPilot/php/express/web/planner.php?id=ASAICA25

ASA PRESS ROOM
In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.

LAY LANGUAGE PAPERS
ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are summaries (300-500 words) of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.

PRESS REGISTRATION
ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting and/or press conferences, contact AIP Media Services at media@aip.org. For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.

ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

ABOUT THE INTERNATIONAL COMMISSION FOR ACOUSTICS
The purpose of the International Commission for Acoustics (ICA) is to promote international development and collaboration in all fields of acoustics including research, development, education, and standardization. ICA’s mission is to be the reference point for the acoustic community, becoming more inclusive and proactive in our global outreach, increasing coordination and support for the growing international interest and activity in acoustics. Learn more at https://www.icacommission.org/.

From Traditional to Technological: Advancements in Fresco Conservation #ASA187

From Traditional to Technological: Advancements in Fresco Conservation #ASA187

Laser Doppler vibrometry is being used to conserve frescos in the US Capitol building

Media Contact:
AIP Media
301-209-3090
media@aip.org

MELVILLE, N.Y., Nov. 21, 2024 – Fresco painting, a technique that dates back to antiquity, involves applying dry pigments to wet plaster, creating stunning artwork that can last for centuries. Over time, however, these masterpieces often face degradation due to delamination, where decorative plaster layers separate from the underlying masonry or structural plaster. This deterioration can compromise the structural integrity of the artwork, necessitating restoration efforts.

Historically, conservators have gently knocked on the plaster with their knuckles or small mallets to assess the condition of the fresco. By listening to the emitted sound, they could identify the delaminated areas needing repair. While effective, this technique is limited both by the conservator’s experience and the small number of people in the world who possess these skills. 

Detection color map of a fresco in the U.S. Capitol. Brighter colors indicate more vibration in the plaster, and therefore, a delamination. Credit: Nick Gangemi

Recent research by Joseph Vignola at the Catholic University of America is revolutionizing fresco assessment. Vignola and his team have applied laser Doppler vibrometry to locate delamination in the frescos of Constantino Brumidi in the U.S. Capitol building. This innovative method uses a laser to measure the vibration of a surface, enabling the team to detect delaminated areas based on their unique vibrational characteristics.

“By transmitting sound waves to induce motion in the plaster, the system captures vibrational signatures that reveal detailed information about the structural condition of the artwork,” said researcher Nicholas Gangemi.

One of the remarkable aspects of this technology is its ability to identify regions of delamination that may not exhibit any obvious outward signs of damage. The group’s current research focuses on developing techniques to accurately resolve the size and shape of these hidden defects, facilitating precise repairs that will ensure the preservation of the artwork for future generations.

Moreover, advancements in signal processing are enhancing the ability to analyze complex shapes of delaminated regions. 

Gangemi will present research related to this work Thursday, Nov. 21, at 11:25 a.m. ET as part of the virtual 187th Meeting of the Acoustical Society of America, running Nov. 18-22, 2024.

This research explores the simulation of frescoes with known delaminated shapes to validate their methods, ensuring that they can accurately assess and restore the artworks. These fresco surrogates have also offered a platform for Vignola and his team to scientifically validate the dated technique of knocking on a fresco and listening to the sound it makes. 

Looking ahead, this research aims to democratize conservation expertise by creating simple, accessible tools. One possibility is to develop smartphone or computer apps that utilize straightforward algorithms, allowing anyone—regardless of their background—to engage with fresco conservation. This initiative not only enhances the preservation process but also raises awareness of the challenges and techniques involved in maintaining these cultural treasures.

As technology continues to bridge the gap between traditional methods and modern science, fresco conservation is poised for a transformative future.

“We are developing techniques to allow us to preserve the artwork for generations to come,” Gangemi said.

———————– MORE MEETING INFORMATION ———————–
​Main Meeting Website: https://acousticalsociety.org/asa-virtual-fall-2024/
Technical Program: https://eppro01.ativ.me/src/EventPilot/php/express/web/planner.php?id=ASAFALL24

ASA PRESS ROOM
In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.

LAY LANGUAGE PAPERS
ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are summaries (300-500 words) of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.

PRESS REGISTRATION
ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the virtual meeting and/or press conferences, contact AIP Media Services at media@aip.org. For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.

ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

Mitigating Train Derailments Through Proactive Condition Monitoring of Rolling Stock

Constantine Tarawneh – constantine.tarawneh@utrgv.edu

University Transportation Center for Railway Safety
University of Texas Rio Grande Valley
Edinburg, Texas, 78539
United States

Popular version of 3aPA4 – Preventing Hot Bearing Derailments via Wireless Onboard Condition Monitoring
Presented at the 187th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0035227

–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–


The 2023 train derailment that occurred in East Palestine, OH, brought attention to the limitations of the detectors currently used in the industry. Typically, the health of train bearings is monitored intermittently through wayside temperature detection systems that can be as far as 40 miles apart. Nonetheless, catastrophic bearing failure is often sudden and develops rapidly. Current wayside detection systems are reactive in nature and depend on significant temperature increases above ambient. Thus, when these systems are triggered, train operators rarely have enough time to react before a derailment occurs, as it did in East Palestine, OH. Multiple comprehensive studies have shown that the temperature difference between healthy and faulty bearings is not statistically meaningful until the onset of catastrophic failure. Thus, temperature alone is an insufficient metric for health monitoring.

Video 1. Vibration and noise emitted from train bearings.

Over the past two decades, we have demonstrated vibration-based solutions for wireless onboard condition monitoring of train components to address this problem. Early stages of bearing failure are reliably detected via vibrations and acoustics signatures, as shown in Video 1, which can also be used to determine the severity and location of failure. This is accomplished in three levels of analysis where Level 1 determines the bearing condition based on the vibration levels within the bearing as compared to a maximum vibration threshold for healthy bearings. In Level 2, the vibration signature is analyzed to identify the defective component within the bearing, and Level 3 estimates the size of the defect based on a developed correlation that relates the vibration levels to defect size.

To demonstrate this process, Figure 1 provides the vibration and temperature profiles for two bearings. Examining the vibration profile, the vibration levels within bearing R7 exceed the maximum threshold for healthy bearings 730 hours into the test, thus indicating a defective bearing. At the same time, the operating temperature of that bearing never exceeded the normal operating range, which would suggest that the bearing is healthy. Upon teardown and visual inspection, we found severe damage to the bearing components at the raceways, as pictured in Figure 2. Despite severe damage all around the bearing inner ring (cone), the operating temperature did not indicate any abnormal behavior.

Figure 1: Vibration and temperature profiles of two railroad bearings showcasing how vibration levels within the bearings can indicate the development of defects while operating temperature does not exhibit any abnormal behavior.
Figure 2: Picture of the damage that developed within bearing R7 (refer to Figure 1). Interestingly, the bearing inner ring (cone) had severe damage and a crack that the vibration levels picked up but not the operating temperature.

We believe that vibration-based sensors can provide proactive monitoring of bearing conditions affording rail operators ample time to detect the onset of bearing failure and schedule non-disruptive maintenance. Our work aims to continue to optimize these new methods and help the rail industry deploy these technologies to advance rail safety and efficiency. Moreover, this research program has had an extraordinary transformative impact from the local to the national level by training hundreds of engineers from underrepresented backgrounds and positioning them for success in industry, government, and higher education.

Understanding rapid fluid flow from the passage of a sound wave

James Friend – jfriend@ucsd.edu

Medically Advanced Devices Laboratory, Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA, 92093, United States

Popular version of 1pPA6 – Acoustic Streaming
Presented at the 187th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0035040

–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–


Acoustic streaming is the flow of fluid driven by the interaction of sound waves with a fluid. Traditionally, this effect was viewed as slow and steady, but recent research shows it can cause fluids to flow rapidly and usefully. To understand how this mechanism works, the researchers devised an entirely new approach to the problem, spatiotemporally separating the acoustics from the fluid flow, providing a closed-form solution, a first. This phenomena has applications in areas like medical diagnostics, biosensing, and microfluidics where precise fluid manipulation is needed, and the analysis techniques may be useful from particle physics to geoengineering.

Spider Silk Sound System #ASA186

Spider Silk Sound System #ASA186

Spiderweb silk moves at the velocity of particles in a sound field for highly sensitive, long-distance sound detection.

Media Contact:
AIP Media
301-209-3090
media@aip.org

OTTAWA, Ontario, May 16, 2024 – The best microphone in the world might have an unexpected source: spider silk. Spiders weave webs to trap their insect snacks, but the sticky strands also help spiders hear. Unlike human eardrums and conventional microphones that detect sound pressure waves, spider silk responds to changes in the velocities of air particles as they are thrust about by a sound field. This sound velocity detection method remains largely underexplored compared to pressure sensing, but it holds great potential for high-sensitivity, long-distance sound detection.

Researchers from Binghamton University investigated how spiders listen to their environments through webs. They found the webs match the acoustic particle velocity for a wide range of sound frequencies. Ronald Miles will present their work Thursday, May 16, at 10:00 a.m. EDT as part of a joint meeting of the Acoustical Society of America and the Canadian Acoustical Association, running May 13-17 at the Shaw Centre located in downtown Ottawa, Ontario, Canada.

silk

Larinioides sclopetarius, commonly known as bridge spiders, helped researchers from Binghamton University investigate how spiders listen to their environments through webs as a way to inspire future designs for microphones that would also be able to respond to sound-driven airflow. Image credit: Junpeng Lai

“Most insects that can hear sound use fine hairs or their antennae, which don’t respond to sound pressure,” said Miles, a professor of mechanical engineering. “Instead, these thin structures respond to the motion of the air in a sound field. I wondered how to make an engineered device that would also be able to respond to sound-driven airflow. We tried various man-made fibers that were very thin, but they were also very fragile and difficult to work with. Then, Dr. Jian Zhou was walking in our campus nature preserve and saw a spiderweb blowing in the breeze. He thought spider silk might be a great thing to try.”

Before building such a device, the team had to prove spiderwebs truly responded to sound-driven airflow. To test this hypothesis, they simply opened their lab windows to observe the Larinioides sclopetarius, or bridge spiders, that call the windowsills home. They played sound ranging from 1 Hz to 50 kHz for the spiders and measured the spider silk motion with a laser vibrometer. They found the sound-induced velocity of the silk was the same as the particles in the air surrounding it, confirming the mechanism that these spiders use to detect their prey.

“Because spider silk is, of course, created by spiders, it isn’t practical to incorporate it into the billions of microphones that are made each year,” said Miles. “It does, however, teach us a lot about what mechanical properties are desirable in a microphone and may inspire entirely new designs.”

———————– MORE MEETING INFORMATION ———————–
​Main Meeting Website: https://acousticalsociety.org/ottawa/    
Technical Program: https://eppro02.ativ.me/src/EventPilot/php/express/web/planner.php?id=ASASPRING24

ASA PRESS ROOM
In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.

LAY LANGUAGE PAPERS
ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are summaries (300-500 words) of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.

PRESS REGISTRATION
ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the in-person meeting or virtual press conferences, contact AIP Media Services at media@aip.org. For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.

ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

ABOUT THE CANADIAN ACOUSTICAL ASSOCIATION/ASSOCIATION CANADIENNE D’ACOUSTIQUE

  • fosters communication among people working in all areas of acoustics in Canada
  • promotes the growth and practical application of knowledge in acoustics
  • encourages education, research, protection of the environment, and employment in acoustics
  • is an umbrella organization through which general issues in education, employment and research can be addressed at a national and multidisciplinary level

The CAA is a member society of the International Institute of Noise Control Engineering (I-INCE) and the International Commission for Acoustics (ICA), and is an affiliate society of the International Institute of Acoustics and Vibration (IIAV). Visit https://caa-aca.ca/.

What could happen to Earth if we blew up an incoming asteroid?

Brin Bailey – brittanybailey@ucsb.edu

University of California, Santa Barbara, Physics Department, Santa Barbara, CA, 93106, United States

Popular version of 4aPA12 – Acoustic ground effects simulations from asteroid disruption via the ‘Pulverize It’ method
Presented at the 186 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0027433

–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–

Let’s imagine a hypothetical scenario: a new asteroid has just been discovered, on a path straight towards Earth, threatening to hit us in just a few days. What can we do about it?

A new study funded by NASA is trying to answer that question. Pulverize It, or PI for short, is a proposed method for planetary defense–the effort of monitoring and protecting Earth from incoming asteroids. In essence, PI’s plan of attack is to penetrate an incoming asteroid with high-speed, bullet-like projectiles, which would split the asteroid into many smaller fragments (pieces) (Figure 1). PI’s key difference from other planetary defense methods is its versatility. It is designed to work for a wide variety of scenarios, meaning that PI could be used whether an asteroid impact is one year away or one week away (depending on the asteroid’s size and speed).

asteroid

Figure 1. PI works by penetrating an asteroid with a high-speed, high-density projectile, which rapidly converts a portion of the asteroid’s kinetic energy into heat and shock waves within the rocky material. The heat energy of the impact locally vaporizes and ionizes material near the impact site(s), and the subsequent shock waves damage and fracture the asteroid material as they move and pass (refract) through it.

How is this possible, and how could the asteroid fragments affect us here on Earth? Rather than using momentum transfer–like in methods such as asteroid deflection, as demonstrated by NASA’s recent Double Asteroid Redirection Test (DART) mission–PI utilizes energy transfer to mitigate a threat by disassembling (or breaking apart) an asteroid.

If the asteroid is blown apart while far away from Earth (generally, at least several months before impact), these fragments would miss the planet entirely. This is PI’s preferred mode of operation,as it is always more favorable to keep the action away from us when possible. In a scenario where we have little warning time (a “terminal” scenario), the small asteroid fragments may enter Earth’s atmosphere–but this is part of the plan (Figure 2).

asteroid

Figure 2. In a short-warning scenario where the asteroid is intercepted and broken up close to Earth (“terminal” scenario), the fragment cloud enters Earth’s atmosphere. Each fragment will burst at high altitude, dispersing the energy of the original asteroid into optical and acoustical ground effects. As the fragments in the cloud spread out, they will enter the atmosphere at different times and in different places, creating spatially and temporally de-correlated shock waves. The spread of the fragment cloud depends on a variety of factors, mainly intercept time (the amount of time between asteroid breakup and ground impact) and fragment disruption velocity (the speed and direction at which fragments move away from the fragment cloud’s center of mass).

Earth’s atmosphere acts as a bulletproof vest, shielding us from harmful ultraviolet radiation, typical space debris, and, in this case, asteroid fragments. As these small rocky pieces enter the atmosphere at very high speeds, air molecules exert large amounts of pressure on them. This puts stress on the rock and causes it to break up. As the fragment’s altitude decreases, the atmosphere’s density increases. This adds heat and increases pressure until the fragment can’t remain intact anymore, causing the fragment to detonate, or “burst.”

When taken together, these bursts can be thought of as a cosmic fireworks show. As each fragment travels through the atmosphere and bursts, it produces a small amount of light (like a shooting star) and pressure (as a shock wave, like a sonic boom). The collection of these optical and acoustical effects, referred to as “ground effects,” work to disperse the energy of the original asteroid over a wide area and over time. In reasonable mitigation scenarios that are appropriate for the incoming asteroid (for example, based on asteroid size or by breaking the asteroid into a very large number of very small pieces), these ground effects result in little to no damage.

In this study, we investigate the acoustical ground effects that PI may produce when blowing apart an incoming asteroid in a “terminal” scenario with little warning. As each fragment enters Earth’s atmosphere and bursts, the pressure released creates a shock wave, carrying energy and creating an audible “boom” for each fragment (a sonic boom). Using custom codes, we simulate the acoustical ground effects for a variety of scenarios that are designed to keep the total pressure output below 3 kPa–the pressure at which residential windows may begin to break–in order to minimize potential damage (Figure 3).

Figure 3. Simulation of the acoustical ground effects from a 50 m diameter asteroid which is broken into 1000 fragments one day before impact. The asteroid is modeled as a spherical rocky body (average density of 2.6 g/cm3) traveling through space at 20 km/s and entering Earth’s atmosphere at an angle of 45°. The fragments move away from each other at an average speed of 1 m/s. The sonic “booms” produced by the fragment bursts are simulated here based upon the arrival of each shock wave at an observer on the ground (indicated by the green dot in the left plot). Note that both plots take into account the constructive interference between shock waves. Left: real-time pressure. Right: maximum pressure, where each pixel displays the highest pressure it has experienced. The dark orange lines, which display higher pressure values, signify areas where two shock waves have overlapped.

Figure 4. Simulation of the acoustical ground effects from an unfragmented (as in, not broken up) 50 m diameter asteroid. The asteroid is modeled as a spherical rocky body (average density of 2.6 g/cm3) traveling through space at 20 km/s and entering Earth’s atmosphere at an angle of 45°. Upon entering and descending through Earth’s atmosphere, the asteroid undergoes a great amount of pressure from air molecules, eventually causing the asteroid to airburst. This burst releases a large amount of pressure, creating a powerful shock wave. Left: real-time pressure. Right: maximum pressure, where each pixel displays the highest pressure it has experienced.

Our simulations support that the ground effects from an asteroid blown apart by PI are vastly less damaging than if the asteroid hit Earth intact. For example, we find that a 50-meter-diameter asteroid that is broken into 1000 fragments only one day before Earth impact is vastly less damaging than if it was left intact (Figure 3 versus Figure 4). In the mitigated scenario, we estimate that the observation area (±150 km from the fragment cloud’s center) would experience an average pressure of ~0.4 kPa and a maximum pressure of ~2 kPa (Figure 3). In the unfragmented asteroid case (as in, not broken up), we estimate an average pressure of ~3 kPa and a maximum pressure of ~20 kPa (Figure 4). The asteroid mitigated by PI keeps all areas below the 3 kPa damage threshold, while the maximum pressure in the unmitigated case is almost seven times higher than the threshold.

The key is that the shock waves from the many fragments are “de-correlated” at any given observer, and hence vastly less threatening. Our findings suggest that PI is an effective approach for planetary defense that can be used in both short-warning (“terminal” scenarios) and extended warning scenarios, to result in little to no ground damage.

While we would rather not use this terminal defense mode–as it is preferable to intercept asteroids far ahead of time–PI’s short-warning mode could be used to mitigate threats that we fail to see coming. We envision that asteroid impact events similar to the in Chelyabinsk airburst in 2013 (~20 m diameter) or Tunguska airburst in 1908 (~40-50 m diameter) could be effectively mitigated by PI with remarkably short intercepts and relatively little intercept mass.

Website and additional resources
Please see our website for further information regarding the PI project, including papers, visuals, and simulations. For our full suite of ground effects simulations, please check our YouTube channel.

Funding
Funding for this program comes from NASA NIAC Phase I grant 80NSSC22K0764 , NASA NIAC Phase II grant 80NSSC23K0966, NASA California Space Grant NNX10AT93H and the Emmett and Gladys W. fund. We gratefully acknowledge support from the NASA Ames High End Computing Capability (HECC) and Lawrence Livermore National Laboratory (LLNL) for the use of their ALE3D simulation tools used for modeling the hypervelocity penetrator impacts, as well as funding from NVIDIA for an Academic Hardware Grant for a high-end GPU to speed up ground effect simulations.