cover

Final Documentation: Beats Exposed

About the Project

Beats Exposed is an interactive performance experience that breaks down the barrier between audience and performer. By exposing the body’s vital signs, the performer invites the audience to see beyond the polished act and into the extreme physical and personal effort.

Beats Exposed is built to be used in performance on, or off, stage. It is lightweight and able to run in a variety of settings.

The current iteration of the project is performed with an aerialist. It exposes the exertion in an artform that is extremely demanding, yet typically meant to appear effortless.

The performer wears a Polar pulse sensor and Moteino wireless transceiver while performing. The transceiver communicates wirelessly with a second Moteino transceiver connected to a computer. The pulse is transferred serially to a P5 program with both audio and visualizations.

In this experience, the audience hears the sound of a heartbeat timed with the performer’s pulse. The visualization, also reacting to the pulse, projects from the ceiling onto the performer, surrounding area, and any audience members that have come in close. The resulting experience is intimate, personal and engaging.

The project website is beatsexposed.com.

Here are photos from our PComp Final setup.

both
lisa3
lisa1-1000
danielle
lisa2

Here’s a video of it working during a playtest at my house:

In this video, taken directly after the performance, you can see the pulse of the performer beating rapidly through the projection on the floor:

This video cycles through some P5 projections:

The final project includes additional projections built by Danielle Butler.

Project Background

Beats Exposed is a collaboration between a lighting designer and two aerialists with backgrounds including work in the circus and on Broadway. We came together to build a experience that breaks down the barrier between audience and performer that is present in most traditional performances.

Performance often aims to transport its audience from reality with theatrical lighting, dramatic costumes, and fantastical feats that seem “effortless.” This type of performance can be striking, but it comes with a high ticket cost, confines on location, and the need for a large audience. These constraints can be extremely limiting.

In this collaboration we wanted to examine these fantastical feats from a different perspective—one that embraces and exposes the physicality as a tool for connecting human to human. It is meant to take away the glass wall and “effortlessness” of performance. It is a moment by moment reminder of the performer’s physicality, vitality and mortality.

We also wanted to tackle issues of accessibility. We believe that performance art is something that should be accessible to all. Creating a performance experience that could be used outside of traditional venues allows us to share the experience to non-traditional audiences.

Audience

Beats Exposed is created around the concept of connectivity. The project is designed to appeal to a wide range of people, no technology or performance understanding is necessary. The project explores how revealing the vitals of a performer can deepen the experience of a viewer, this connectivity can occur on a subconscious or conscious level, allowing access to people of all ages and experiences. On the surface it is a visually stimulating experience of adept physicality encased in projected light and designs that move with the sound of the performer’s heartbeat. Exploring deeper reveals the technology that drives the project. Similar to the heartbeat it is hidden inside a small wearable, radio waves and code.

Hardware

Polar pulse sensor with transmitter and receiver.
Polar pulse sensor with transmitter and receiver.

Our method for measuring the heart beat of the performer changed drastically over the course of our testing. The first version we used worked via sticky electrodes attached to the chest and connected to an EKG frontend that measures the minute voltages generated by the heart. We ran into issues when the performer was doing anything other than being seated, as body movement generated a lot of noise. We then tried a different EKG frontend circuit which was similar to those found in exercise equipment, but again noise became a huge issue whenever the performer moved.

After ample research, we began to learn that it was necessary to measure body movement alongside the heartbeat, in order to eliminate the body movement noise from the heartbeat electrodes. We found a product–the Polar T34 pulse monitor that does this processing automatically. By using this product as our sensor, we were able to get a very accurate heartbeat pulse that was free from any noise.

Our final human interface works by receiving a pulse signal from the Polar monitor for every heartbeat, which is then transmitted wirelessly via Monteino transmitter (over a 915MHz serial bridge) that is worn by the performer. This 915MHz signal is then received by a second Moteino that sends the pulse along to P5 via serial. In order to make sure that P5 sees every pulse, each heart beat is about 320ms long.

Code

The code behind this project is written in Arduino and P5. It is available on Github here.

Humbling Outcomes: What We Learned

Our original proposal included a breath/stretch sensor in addition to the pulse sensor. We thought implementing this would be relatively simple. In reality, the stretch sensor was very sensitive to movement and we were unsuccessful at getting a usable reading.

It took three iterations over about one month to get the pulse sensor working as we intended. We tried an optical pulse sensor, a three electrode EKG heart monitor, and a two electrode heartbeat monitor. All three of these sensors were plagued with electrical noise whenever the performer moved. Finally we arrived at the Polar T34 heartbeat band, which is designed to produce a reliable heartbeat even during times of heavy physical movements. We found this band provided an extremely accurate representation of the performers heartbeat, even when they were moving.

We spent a lot of time working with the the serial communication to get a reliable signal. Once the signal was in P5, we found we had to simplify our sketches significantly in order for them to run reliably. In the future we would likely try to use Processing for visuals.

Interestingly, some of our testers had a negative reaction to the sound of the heartbeat played over headphones. We don’t yet understand why some find the sound unbearable, while others find it centering and calming. We will continue to refine the sound and user test to get a better understanding of this sensitivity.

Thanks

Thanks to the great community at ITP we had a lot of help with the technical aspects of our project. We would like to thank ITP resident J. H. Moon for his help with our p5.js code, and ITP Professor Benedetta Piantella for helping us implement the wireless serial bridge to transmit our sensors to our visuals. Many second year students were also happy to support us and answer our questions including Thea Rae, Justin Peake, and Joe Mango.

Submit a comment

Your email address will not be published. Required fields are marked *