Emmanuel Fléty, SPA(S)M 2/4 : The Epic Tale of Embedded Electronics

The Artistic Residency Blog

Entering the Engineering and Prototyping workshop on IRCAM's first basement floor, and meeting Emmanuel Fléty, opens the door to a little-known side of the institute's research and, more broadly, of the world of embedded devices. What goes on here, in this hodgepodge where the latest 3D printers rub shoulders with a mosaic of screens, stacks of oscilloscopes and cupboards overflowing with electronic boxes—vintage or otherwise—is a high-level craft, combining new lutheries and electronic geek genius.

Emmanuel Flety @ircam

"Geek": the word has been dropped, and Emmanuel Fléty embraces it with an aplomb that's not lacking in humor and pride. For the man is a true enthusiast, as well as an outstanding historian of his field. Since his first forays into the marvellous world of electronics, he has witnessed the passage of successive technologies and standards: those we remember (MIDI), those we've forgotten (like the memory chips we had to bake for 15 minutes to erase them before reprogramming them - a cycle that had to be repeated every time, for the slightest code correction or improvement), and those that are in use today (like the Internet of Things, which "saved us", says Fléty).

An inspired tinkerer from his early teens, Emmanuel Fléty first studied electrical engineering and industrial computing (at the IUT in Ville d'Avray, where he has fond memories of creative freedom in a discipline that was still in its infancy), then went on to train as an electronics and computing engineer at ENSEA.

"At the time, I was more interested in development, but even then I was curious about embedded electronics, a field that lies at the crossroads of electronics and computer science, from manufacturing to programming. I liked automated systems, like those that control certain processes in cars or those that equip elevators. I found it quite magical: how does the elevator computer manage priority rules, for example? From the very start of my training, I loved making these systems, so I could apply my knowledge in concrete terms right away. I remember my first embedded system. In the early 1990s, I designed and installed a centralized door opening and closing system in a friend's R5, which also closed the windows with just one click. It was a classy feature! At the time, it was a feature found only in luxury cars. That's how I got hooked on microcontrollers, and I really liked both the "laborious craftsmanship" aspect (as a child, I wanted to be a violin or jewelry maker), but also the logistical constraints linked to these devices, and the challenge of doing a lot with a little."

It was in these years that Emmanuel Fléty began collaborating with IRCAM with the Analysis-Synthesis team, as part of an IUT internship. He worked on an analysis module for the Super Phase Vocoder (SVP).

"I took part in the implementation and coding of linear spectrum prediction, making a spectral envelope interpolated in a predictive and linear way from the spectrum, in order to perform cross-synthesis in particular. It was this type of information reduction technique, based on the principle of perceptual weights, that gave rise to MP3."

Emmanuel Flety's studio

A few years later, he was asked by IRCAM to classify sensors for gesture controllers. At the time, electronics was at a standstill at IRCAM, following the abandonment of the 4X. Dismayed by previous failures linked to radical technological choices, the focus shifted to IT, at the expense of hardware, with the rise of what was to become Max.

But this redirection of research efforts obscured an entire field of computer music: the interpretation of electronics by musicians on stage. In other words, the interaction of the musician's playing with the electronics, which can range from simple synchronization to a genuine influence of the performance on the electronic discourse, via real-time modification of synthesis or computer processing parameters.

As it happens, it was also at this time (in the course of the 1990s) that IRCAM launched its famous Cursus program and its students aspired to this kind of interaction. This is why it was necessary to establish the state of the art.

And so Emmanuel Fléty's future career unfolds: a career at the intersection of several milieus, several disciplines, several signals, between acoustics and electronics, the musical and the technical, the artistic and the scientific. And he does it all: device design and manufacture, programming, translation of an audio signal into an electrical signal, then electronics and computers, and vice versa. In technical language, it's called "digitization and acquisition interfaces".

His hobby? Miniaturized low-latency wireless sensors", essential tools not only for motion capture and recognition, but also for the creation of new gestural interfaces and digital lutherie. His day-to-day challenges include device discretion and maneuverability, low latency, easy integration of signals into interfaces, etc...

Over the years, Emmanuel Fléty has developed landmark technologies, such as the AtoMIC Pro, a universal, programmable, industrially-produced 2x16-channel MIDI converter. This is a must-have, "which enabled signals to be digitized as quickly as possible, making the most of the MIDI available at the Tim,"  or the EtherSense, which increased throughput by a factor of 32 while reducing latency, followed by its portable version, the WiSe Box. His experience and adaptability have enabled him to make the most of all standards, such as the OSC (OpenSound Control) invented by David Wessel, which divides the latency of the AtoMic Pro by 32 and which, when released, left the software struggling to keep up!

Emmanuel Flety in his atelier

Moving from one floor of the institute to the next, Emmanuel Fléty takes part in numerous inter-team projects, working on a wide variety of augmented instruments (pianos, violins, violas, cellos, harps, accordions, etc.) or gesture sensors - such as the AtoMic Pro. ) or gesture sensors - such as the revolutionary R-IoT, developed in collaboration with Frédéric Bevilacqua's ISMM (Interaction son musique mouvement) team, which measures 3D movements along 9 axes, and which, since its first version seven years ago, has been used by virtually all IRCAM composers wishing to work on movement.

It's this R-IoT (whose name is a pun on "riot") that ISMM and Emmanuel Fléty are working on once again, notably as part of Basile Chassaing's artistic research residency; the latter's research accompanying and nourishing the tool's development.

Some of the improvements are obvious. The previous R-IoT design dates back to 2017, so a series of updates is needed to deal with the obsolescence of certain standards and components. As a result, the platform is now equipped with a new microcontroller, offering in one fell swoop dual support for the new Bluetooth (Bluetooth Low Energy or BLE) and WiFi standards, as well as extended compatibility with the official Arduino development environment (the previous R-IoT was programmed on what is known as a "fork", i.e. a derivative of the Arduino software base - the term "fork" referring to the bifurcation taken by a code from the official code base).

This also provides an opportunity to simplify the configuration interface, which will be carried out either via a web page or a configuration file, and will include a "Data Logger" function, in other words, in situ recording of the data collected by the sensors.

On the hardware front, this new microcontroller means that the R-IoT will be able to accommodate new sensors (altitude and temperature), as well as more input and output ports for connecting external sensors.

Finally, and perhaps most spectacularly, Emmanuel Fléty plans to make the new platform compatible with a small external display.

"The idea," he says, "is to make a more ergonomic wrist version, to streamline communication between stage and control room, and to facilitate configuration... We're getting closer to what a connected watch offers, but without losing sight of our subject: generating expressivity via the artistic gesture, and doing so wirelessly and with low latency."

In our next episodes, we'll meet Emmanuelle Grach, the choreographer alongside whom Basile Chassaing is working.

[1] Open source prototyping platform that enables users to create interactive electronic objects from hardware-free electronic boards featuring a microcontroller. The schematics of these electronic boards are available under a free license.