This afternoon one of our PhD student researchers, Rod Selfridge, successfully defended his PhD. The form of these exams, or vivas, varies from country to country, and even institution to institution, which we discussed previously. Here, its pretty gruelling; behind closed doors, with two expert examiners probing every aspect of the PhD.
Rod’s PhD was on ‘Real-time sound synthesis of aeroacoustic sounds using physical models.’ Aeroacoustic sounds are those generated from turbulent fluid motion or aerodynamic forces, like wind whistling or the swoosh of a sword. But when researchers simulate such phenomena, they usually use highly computational approaches. If you need to analyse airplane noise, it might be okay to spend hours of computing time for a few seconds of sound, but you can’t use that approach in games or virtual reality. The alternative is procedural audio, which involves real-time and controllable sound generation. But that is usually not based on the actual physics that generated the sound. For complicated sounds, at best it is inspired by the physics.
Rod wondered if physical models could be implemented in a procedural audio context. For this, he took a fairly novel approach. Physical modelling often involves gridding up a space and looking at the interaction between each grid element , such as in finite difference time domain methods. But there are equations explaining many aspects of aeroacoustics, so why not build them directly into the model. This is like the difference between modelling a bouncing ball by building a dynamic model of the space in which it could move, or you could just apply Newton’s laws of motion. And Rod took the latter approach. Here’s a slick video summarising what the PhD is about,
It worked. He was able to apply real-time, interactive physical models of propeller sounds, aeolian tones, cavity tones, edge tones, the aeolian harp, a bullroarer. He won the Silver Design Award and Best Student Paper Award at the 141st AES Convention, and the Best Paper Award at the Sound and Music Computing conference. And he produced some great demonstration videos of his work, like
Rod also contributed a lot of great blog entries,
- Aeroacoustic Sound Effects – Journal Article
- The edgiest tone yet…
- The cavity tone……
- Applied Sciences Journal Article
- Physically Derived Sound Synthesis Model of a Propeller
- International Congress on Sound and Vibration (ICSV) London 2017
- Sound Synthesis of an Aeolian Harp
- The Swoosh of the Sword
- Real-Time Synthesis of an Aeolian tone
So congratulations to Dr. Rod Selfridge, and best of luck with his future endeavours. 🙂
This is the first blog entry I’ve written for a graduating PhD student. I really should do it for all of them- they’ve all been doing great stuff.
And finally, here’s a list of all Rod’s papers as a member of the Intelligent Sound Engineering team.
· R. Selfridge, D. Moffat, E. Avital and J. D. Reiss, ‘Creating Real-Time Aeroacoustic Sound Effects Using Physically Derived Models,’ Journal of the Audio Engineering Society, 66 (7/8), pp. 594–607, July/August 2018, DOI: https://doi.org/10.17743/jaes.2018.0033
· R. Selfridge, D. Moffat and J. D. Reiss, ‘Sound Synthesis of Objects Swinging through Air Using Physical Models,’ Applied Sciences, v. 7 (11), Nov. 2017, Online version doi:10.3390/app7111177
· R. Selfridge, J. D. Reiss, E. Avital, Physically Derived Synthesis Model of an Edge Tone, Audio Engineering Society Convention 144, May 2018
· R. Selfridge, D. Moffat and J. D. Reiss, ‘Physically Derived Sound Synthesis Model of a Propeller,’ Audio Mostly, London, 2017
· R. Selfridge, D. Moffat and J. D. Reiss, ‘Physically Derived Synthesis Model of a Cavity Tone,’ Digital Audio Effects (DAFx) Conf., Edinburgh, September 5–9, 2017
· R. Selfridge, D. J. Moffat and J. D. Reiss, ‘Real-time physical model for synthesis of sword swing sounds,’ Best paper award, Sound and Music Computing (SMC), Helsinki, July 5-8, 2017.
· R. Selfridge, D. J. Moffat, E. Avital, and J. D. Reiss, ‘Real-time physical model of an Aeolian harp,’ 24th International Congress on Sound and Vibration (ICSV), London, July 23-27, 2017.
· R. Selfridge, J. D. Reiss, E. Avital, and X. Tang, “Physically derived synthesis model of aeolian tones,” winner of the Best Student Paper award, 141st Audio Engineering Society Convention USA, 2016.
· R. Selfridge and J. D. Reiss, Interactive Mixing Using the Wii Controller, AES 130th Convention, May 2011.