Thomas L. Szabo1 – tlszabo@bu.edu Peter Kaczkowski2 – peterkaczkowski@verasonics.com
1. Biomedical Engineering Boston University 11335 NE 122nd Way
2. Verasonics, Inc. 44 Cummington Mall Suite 100 Boston, MA 02215 Kirkland, WA 98034
Popular version of 1aED3 – Acoustics education accelerated by interactive simulators and research imaging system experiments Presented Monday morning, November 29th, 2021 181st ASA Meeting Click here to read the abstract
COVID-19 has cast a shadow across college science education. Conventional approaches and flipped classes included a lecture (either live or pre-watched), followed by the solution of specific homework problems done (either independently or in an interactive learning session) and supplemented with laboratories. COVID-19 restricted in-person class and laboratory time. Differences in student background and skill level became apparent, especially in the labor-intensive solution of specific homework problems.
At Boston University, an alternative consisting of a ten-module introductory ultrasound imaging curriculum was developed in which students engaged with course material experientially by using real time Graphical User Interface (GUI)-based physics simulators. These simulators replaced an equation or a set of equations. The simulators allow the user to vary the input variables Xn with a GUI (typically consisting of drop-down menus, sliders, or knobs). The output is in the form of selectable output variables Ym as a function of the subset of chosen input variables Xn. In most simulators, the type of output display is also user selectable.
In this new approach, students interact with simulators accommodating a wide range of skill levels, from beginner to advanced. With guidance, students advance at their own pace and obtain quantitative results in real-time, without traditional bottlenecks associated with homework calculations and mathematical derivations. Because each simulator typically has tens of thousands of input parameter combinations, students have a more global understanding of the concepts. Unlike a typical homework set, these simulators provide students with an understanding of the functional relationship of variables in a continuous and efficient way. Students can learn quickly which variables are most important and their functional interactions.
Interactive simulator for imaging a three dimensional object using typical ultrasound imaging modes.
A frame from a video of transducer manipulation to image a phantom in a laboratory exercise by using an ultrasound research imaging system.
Interactive simulator video
Professor Szabo, under the sponsorship of Verasonics®, worked with several biomedical and electrical engineering graduate students part-time at Boston University for three years to develop programs for the simulators in MATLAB®, a scientific programming language. A set of accompanying lectures explained the software as part of an introductory ultrasound imaging curriculum designed to teach underlying physical principles, signal processing, and image processing concepts. He and Peter Kaczkowski, Director of Ultrasound Science at Verasonics, created a series of focused laboratories to further experience the curriculum principles. Using specialized imaging phantoms, students can learn about the imaging process firsthand, as well as the workings of an imaging system as they follow signals through a Verasonics Vantage™ Research Ultrasound System.
Verasonics is planning to offer a comprehensive course based on the simulators and laboratories. In addition, the authors are writing a companion textbook based on interactive simulators and focused laboratories. Verasonics, a privately held company, in Kirkland, Washington, USA, provides researchers and developers with advanced ultrasound imaging systems and flexible tools. For more information, visit https://verasonics.com/.
How do you give students in an online acoustics course a hands-on lab experience?
At the State University of New York (SUNY) at New Paltz, students in the online sections of “The World of Sound” use a lab kit that was designed by the instructor. Students pay for shipment of the kits to their homes at the start of the course and return them at the end. They submit photos or videos of their activities along with their completed lab reports.
These kits had been in use for several years in an online post-baccalaureate program that prepares students for graduate study in speech-language pathology when the COVID19 pandemic radically changed the undergraduate on-campus version the course.
“The World of Sound” is a four-credit general education lab science course. Undergraduates typically work in groups of three and share equipment within and across lab sections. By summer of 2020, it was clear that on-campus labs in the upcoming fall semester would have to meet social distancing requirements, with no sharing of materials, and that there could be a pivot to fully remote instruction at any time. The cost of the needed individual instructional materials was a consideration due to the fiscal impact of COVID19. A revised lab kit was developed that contains everything needed for seven labs, costs under $30.00, and has a shipping weight of less than two pounds.
About one-fourth of the undergraduates in the course chose to study fully remotely during fall 2020. These students had their kits shipped to them and they attended a weekly virtual lab session. Each student in the seated course was issued an individual lab kit in a shipping box that was addressed to the department for ease of return shipment. Seated labs were conducted with all required precautions including face coverings and social distancing. The kits contained everything needed for each lab, including basic supplies, so no equipment had to be shared.
Although the college was able to keep COVID19 rates low enough to stay open for the entire semester, about 15% of the students in the course transitioned to remote learning at least briefly for reasons such as illness or quarantine, missing a required covid test date, financial issues, or COVID19-related family responsibilities or crises. Having their lab kits in their possession allowed these students to move seamlessly between seated and virtual lab sessions without falling behind. Every undergraduate who studied remotely for part or all of the semester completed the course successfully.
Cameron Vongsawad – cvongsawad@byu.edu Mark Berardi – markberardi12@gmail.com Kent Gee – kentgee@physics.byu.edu Tracianne Neilsen – tbn@byu.edu Jeannette Lawler – jeannette_lawler@physics.byu.edu Department of Physics & Astronomy Brigham Young University Provo, Utah 84602
Popular version of paper 2pED, “Development of an acoustics outreach program for the deaf” Presented Tuesday Afternoon, May 19, 2015, 1:45 pm, Commonwealth 2 169th ASA Meeting, Pittsburgh Click here to read the abstract.
The deaf and hard of hearing have less intuition with sound but are no strangers to the effects of pressure, vibrations, and other basic acoustical principles. Brigham Young University recently expanded their “Sounds to Astound” outreach program (sounds.byu.edu) and developed an acoustics demonstration program for visiting deaf students. The program was designed to help the students connect to a wide variety of acoustical principles through highly visual and kinesthetic demonstrations of sound as well as utilizing the students’ primary language of American Sign Language (ASL).
In science education, the “Hear and See” methodology (Beauchamp 2005) has been shown to be an effective teaching tool in assisting students to internalize new concepts. This sensory-focused approach can be applied to a deaf audience in a different way, the “See and Feel” method. In both, whenever possible students participate in demonstrations to experience the physical principle being taught.
In developing the “See and Feel” approach, a fundamental consideration was to select the principles of sound that were easily communicated using words that exist and are commonly used in ASL. For example, the word “pressure” is common, while the word “wave” is uncommon. Additionally, the sign for “wave” is closely associated with a water wave, which could lead to confusion about the nature of sound as a longitudinal wave. In the absence of an ASL sign for “resonance,” the nature of sound was taught by focusing on the signs for “vibration” and “pressure.” Additional vocabulary, i.e., mode, amplitude, node, antinode, and wave propagation, were presented using classifiers (non-lexical visualizations of gestures and hand shapes) and finger spelling the words. (Sheetz 2012)
Two bilingual teaching approaches were tried to make ASL the primary instruction language while also enabling communication among the demonstrators. In the first approach, the presenter used ASL and spoken English simultaneously. In the second approach, the presenter used only ASL and other interpreters provided the spoken English translation. The second approach proved to be more effective for both the audience and the presenters because it allowed the presenter to focus on describing the principles in the native framework of ASL, resulting in a better presentation flow for the deaf students.
In addition to the tabletop demonstrations (illustrated in the figures), the students were also able to feel sound in BYU’s reverberation chamber as a large subwoofer was operated at resonance frequencies of the room. The students were invited to walk around the room to find where the vibrations felt weakest. In doing so, the students mapped the nodal lines of the wave patterns in the room. In addition, the participants enjoyed standing in the corners of the room, where the sound pressure is eight times as strong and feeling the power of sound vibrations.
The experience of sharing acoustics with the deaf and hard of hearing has been remarkable. We have learned a few lessons about what does and doesn’t work well with regards to the ASL communication, visual instruction, and accessibility of the demos to all participants. Clear ASL communication is key to the success of the event. As described above, it is more effective if the main presenter communicates with ASL and someone else, who understands ASL and physics, provides a verbal interpretation for non-ASL volunteers. Having a fair ratio of interpreters to participants gives individualized voices for each person in attendance throughout the event. Another important consideration is that the ASL presenter needs to be visible to all students at all times. Extra thought is required to illuminate the presenter when the demonstrations require low lighting for maximum visual effect.
Because most of the demonstration traditionally rely on the perception of sound, care must be taken to provide visual instruction about the vibrations for hearing-impaired participants. (Lang 1973, 1981) This required the presenters to think creatively about how to modify demos. Dividing students into smaller groups (3-4 students) allow each student to interact with the demonstrations more closely. (Vongsawad 2014) This hands-on approach will improve the students’ ability to “See & Feel” the principles of sound being illustrated in the demonstrations and benefit more fully from the event.
While a bit hesitant at first, by the end of the event, students were participating more freely, asking questions and excited about what they had learned. They left with a better understanding of principles of acoustics and how sound affects their lives. The primary benefit, however, was providing opportunities for deaf children to see that resources exist at universities for them to succeed in higher education.
Acknowledgments We would like to acknowledge support for this work from a National Science Foundation Grant (IIS-1124548) and from the Sorensen Impact Foundation. The visiting students also took part in a research project to develop a technology referred to as “Signglasses” – head-mounted artificial reality displays that could be used to help deaf and hard of hearing students better participate in planetarium shows. We also appreciate the support from the Acoustical Society of America in the development of BYU’s student chapter outreach program, “Sounds to Astound.” This work could not have been completed without the help of the Jean Massieu School of the Deaf in Salt Lake City, Utah.
Figure 1: Vibrations on a string were made to appear “frozen” in time by matching the frequency of a strobe light to the frequency of oscillation, which enhanced the ability of students to analyze the wave properties visually.
Figure 2: The Rubens Tube is another classic physics and acoustics demonstration to show resonance in a pipe. Similarly to the vibrations on a string, but this time being affected by sound waves directly. A speaker is attached to the end of a tube full of propane and the exiting propane that is lit on fire shows the variations in pressure due to the pressure wave caused by the sound in the tube. Here students are able to visualize a variety of sound properties.
Figure 3: Free spectrum analyzer and oscilloscope software was used to visualize the properties of sound broken up into its derivative parts. Students were encouraged to make sounds by clapping, snapping, using a tuning fork or their voice, and were able to see that sounds made in different ways have different features. It was significant for the hearing-impaired students to see that the noises they made looked similar to everyone else’s.
Figure 4: A loudspeaker driven at a frequency of 40 Hz was used to first make a candle flame flicker and then blow out as the loudness was increased to demonstrate the power of sound traveling as a pressure wave in the air.
Figure 5: A surface vibration loudspeaker placed on a table was another effective demonstration for the students to feel the sound. Students felt the sound as the surface vibration loudspeaker was placed on a table. Some students placed the surface vibration loudspeaker on their heads for an even more personal experience with sound.
Figure 6: Pond foggers use high frequency and high amplitude sound to turn water into fog, or cold water vapor. This demonstration gave students the opportunity to see and feel how powerful sound or vibrations can be. They could also put their fingers close to the fogger and feel the vibrations in the water.
This video demonstrates the use of ASL as the primary means of communication for students. Communication in their native language improved understanding.
References
Michael S. Beauchamp, “See me, hear me, touch me: Multisensory integration in lateral occipital-temporal cortex,” Cognitive Neuroscience: Current Opinion in Neurobiology 15, 145-153 (2005).
N. A. Scheetz, Deaf Education in the 21st Century: Topics and Trends (Pearson, Boston, 2012) pp. 152-62.
Cameron T. Vongsawad, Tracianne B. Neilsen, and Kent L. Gee, “Development of educational stations for Acoustical Society of America outreach,” Proc. Mtgs. Acoust. 20, 025003 (2014).
Harry G. Lang, “Teaching Physics to the Deaf,” Phys. Teach. 11, 527 (September 1973).
Harry, G. Lang, “Acoustics for deaf physics students,” Phys. Teach. 11, 248 (April 1981).
