The workshop introduced participants to the Arduino platform and various approaches to designing gestural sensing systems. Below you can see our most recent wearable interface prototype (built as part of our ongoing creative R&D with Legs on the Wall) which has been extended to include a glove based interface in addition to flex and accelerometer sensors.
Wearable prototype #2 and joystick
The second prototype has been designed so that it can be retrofitted to different performers of different sizes. Donna has used a neoprene and velcro system to mount sensors and provided a means to replace or change sensors via locking connectors for each sensor. The workshop also provided an opportunity to give an overview of the Max/Jitter patching environment and how gestural data was mapped in the process of achieving successful and engaging creative outcomes.
Donna Hewitt showing wearable prototype #1
The workshop participants had a broad range of prior knowledge (from little, to quite a lot), but all seemed to get a lot out of the workshop process. And besides… it’s such a lovely building.
General – $20.00
Industry – $15.00
Student/Educator – $10.00
Donna Hewitt – Macrophonics
In late 2012 the artist collective Macrophonics visited internationally-recognised physical theatre company, Legs On The Wall, to experiment with sensor-based technology and how it can be adapted specifically for live performances. What emerged was a tool for creating live art, one that uses both the body of a performer and the space they move through. Now Macrophonics and Legs On The Wall offer audiences a glimpse into what comes next – the creation of a new work that transforms the dancer into the conductor, the musician into the actor, and the stage into the interface.
This presentation will feature Professor Julian Knowles of Macquarie University’s Department of Media, Music, Communication and Cultural Studies and Patrick Nolan, Artistic Director of Legs On The Wall, and a demonstration of the Macrophonics technology with performer Tim Ohl.
THE MAKING OF…
In a series of fast-paced, one-hour tag-team sessions, creative teams from the worlds of television, gaming, music, and animation take us behind-the-scenes to introduce us to the people and processes that make huge creative projects a reality.
These sessions explore strategies for making international real-time collaborations work, find out what tools are essential for co-ordinating multi-part projects, and meet some of the world’s most interesting companies and creatives.
Radio Interview with Julian Knowles – 2SER Sydney, Australia (from 17:20 onwards)
While Donna works on building the wearable top with sensors, Julian is working on making ‘musical scenes’. These scenes are modular, with a range of musical elements which can be triggered or manipulated in an improvisational manner. They are designed for non-musician physical theatre performers/acrobats. The wearable top will have a Triaxial Accelerometer (reading X, Y, Z axes) mounted on the right arm, a flex sensor on the left elbow and some buttons. Julian has been using a Wii remote to simulate the accelerometer and buttons so he can work on parameter mapping and prototype some a/v scenes while Donna is working on building the wearable interface. The Wii remote can act as a hand held device which contains much of the functionality of the wearable (accelerometer and buttons)
Nintendo Wii Remote (Wiimote) puts out pitch, roll, yaw and z (g force) data
Julian is using the fantastic software Osculator to take the bluetooth Wiimote data and convert it to midi. He is then streaming the midi into a patch in MaxMSP which allows him to condition, scale and route the data streams before they get sent to Ableton Live to control audio.
The system is very robust and today Julian had it working to a distance of over 15 metres. Let’s hope the wifi from the Lilypad is as solid. Here is an example of the wii remote being used to control audio. The accelerometer XYZ outputs control various audio filter processing parameters and volume changes, while the buttons are used to trigger audio events.
On the video side, Julian has been building a realtime video processing system in the Jitter environment.
The following example shows the wii remote accelerometer XYZ parameters mapped to video processing. No audio processing is taking place in this example. Julian is just listening to some music while he programs and tests the video processing system. In this example the wii remote is driving a patch Julian has written in Jitter. A quicktime movie is used as input and the wiimote is driving real time processing. Julian has also extended the jitter patch to allow it to process a live camera input.
Donna has been working away on the wearable interface that will contain the functionality of the above (plus more). She has been designing the layout of the sensors and working out how to connect everything within the given constraints of the LilyPad system. The conductive thread that can be used to sew the sensors in and connect to the main board has quite a high resistance, and so runs need to be kept short. Likewise the run between the battery board and the Lilypad/Xbee board needs to be short, so as to keep maximum current available. Runs of conductive thread cannot be crossed over or they will short out.
Donna – roughing out the sensors on a black sports top
We’re hoping to get the wearable interface completed in the next day or two so we can start to test it out with the modular musical materials. For the purposes of the showing, we’ll demonstrate three a/v ‘scenes’ in sequence, demonstrating different approaches and relationships between gesture and media.
The first scene will be drone/video synthesis based (with the performers stage positions driving processing). This state will have a very strong correlation between the audio and video processing gestures and will allow for multiple performers moving in relation to ultrasonic range finder sensors.
The second scene will involve the wearable interface, with direct/detailed gestural control of audio and video elements from a solo performer.
The third involve a complex interplay of sensors and parameters. The wearable interface will perform time domain manipulation and transport control on quicktime materials whilst driving filters and processors in the audio domain. The scene will also make use of physical objects sounding on stage, driven by the wearable interface. The interface data will be used to control signals flowing through physical objects (in this case cymbals and a snare drum) and audio/spatial relationships will unfold between the performer’s gestures, proximity to objects and sound behaviours. Tim is taking care of the actuator setup.
Wearable interface. Pressure sensors on the shoulder blades.
Ultimately we are aiming for a fully responsive media environment. The aim is for the stage performer(s) to drive both audio and video elements and feel immersed in a highly responsive mediascape.
Wearable interface. Pressure sensors on shoulder blades
We’re now well into our Macrophonics Open Source creative development project at Legs on the Wall in Sydney. Lots of experimentation going on at this stage and we’ll start to resolve things down during the week before our stint in the theatre next week. We’ve opened out the exploration to sounding objects – driving audio signals into snare drums, cymbals and other resonant objects to set them off acoustically. The idea is that certain parts of the stage area contain assemblages of resonant objects and, through video and hardware sensing, performers will be able to activate the array of objects within an auditory ‘scene’ that we create. These auditory scenes will contain flexible sonic ‘modules’ – collections of sounds and musical motifs that can be recombined freely.
15″ loudspeaker driver coupled to a 15″ snare
At the moment, we’re experimenting to find the resonant frequency of each of the trial objects. We also want to get a sense of how the objects behave with different input signals. At the moment, we’ve set up the input to the ‘actuators’ to run from discrete sends so that they can be blended/balanced with the signals from the main loudspeakers. From a control perspective, we will compare wearable sensors (using the Lilypad Arduino platform) located on the performer, with video tracking from above the stage. The wearable sensors have the advantage of being robust in respect of different lighting states, but need to be protected from damage by the physical theatre performer. This could prove challenging. The video tracking approach is robust from a physical point of view, but highly light dependant – so changing light conditions can affect the threshold settings for the tracking patches so that tracking becomes less reliable through changing light states.
Donna working with Lilypad Arduino. Seen here with small accelerometer sensor
The plan is to use the accelerometers on the wrists of the performers so that arm movements and rotations will output X,Y,Z co-ordinates. We’ll also be trying out light sensors on the performers, flex sensors and some heat sensors. The Lilypad is a great platform for wearable computing – the main issue is the small number of analog inputs, so we will need to investigate the potential to have multiple Lilypads sending data over wifi (via the Xbee platform) to a single computer. If this poses an issue for us, we could mount a second Lilypad/Xbee set up and have it transmitting to a second receiver at a second computer. As we have not yet established an approach to data mapping and distribution to the media performers, this second model may actually be more ergonomic. We shall see.
Lilypad Arduino with Lilypad Xbee (top left) at Donna’s workstation
In the shot above you can see the Lilypad Arduino connected to a Lilypad Xbee board which takes care of the wireless communication of sensor data to an Xbee receiver at the computer. The Lilypad Xbee is currently getting power from a USB cable, but will soon be powered by an AAA battery. Once all the sensors have been connected up and prototyped in this way, the whole thing will be sewn into a garment and the sensors will be connected to the board via conductive thread.
Julian Knowles and Tim Bruniges (positioning sonic actuators). Photo: Lucy Parakhina
The Macrophonics artist collective has just commenced our Open Source media technologies residency with Sydney based physical theatre company Legs on the Wall at their Red Box development space. Background information on the project can be found here.
Macrophonics live – Brisbane Festival 2011
The residency sees the group examine a range of interface technologies and approaches to explore the nexus between theatrical performers and a four member live media ensemble. The objective is to build a responsive performance environment that will allow the theatre performers to have direct gestural input into the media control system, defining new relationships between the performance ensemble, the media design elements and the media ensemble.
We’ve broadly structured our investigation across two approaches. The first is video tracking/computer vision techniques (using the cv.jit suite of objects for Jitter) where the stage area can be analysed and moving objects tracked.
Jitter patch – cv.jit suite of ‘computer vision’ (video analysis) objectsMoving masses in the video frame are identified and then tracked
The second area of investigation is wearable garment interfaces that sense movement directly at each performer (accelerometers, pressure and flex sensors, light sensors etc) and send data wirelessly to the media ensemble. We are using the LilyPad Arduino platform for this work. The LilyPad is a small, flat implementation of the Arduino platform that can be sewn into garments. Conductive ‘thread’ can then be sewn in ‘tracks’ into the garment to form the links between the device and the attached sensors.
LilyPad Arduino
The LilyPad can be run from a battery source and can, with a bit of extra stuff, transmit data wirelessly over an ad hoc wireless network.
Lilypad arduino sewn into garment with conductive thread. Image credit: Rain Rabbit (flickr)Donna’s LilyPad – ready for sewing
donna hewitt : julian knowles : tim bruniges : wade marynowsky
