PI: Dr. Jennifer G. Sheridan, BigDog Interactive, Lancaster
Co-I (technology): Dr. Nick Bryan-Kinns, IMC Group, Computing Department, Queen Mary, University of London (Versions 1.1, 2.0, 2.1, 3.0/1)
Expert poier consultant: Matt Cooper
Additional Sound: Robin Fencott, Middlesex University (version 3.1)
Former Co-I (performance, v1.1/2005/2006): Alice Bayliss, School of Performance and Cultural Industries, Leeds University
Former Co-I (technology, v1.0/2005): Nick Villar, Computing Department, Lancaster University
About iPoi
What is Poi?
Imagine swinging a tiny computer around your body to create live visuals and audio like a DJ or VJ. iPoi is based on the ancient Maori art of poi and uses a wireless, peer-to-peer, sensor-packed upgrade of the original. iPoi is created by embedding tiny computers in tennis balls and socks, and swinging them wildly around your body. iPoi uses the wonder of acceleration, the hidden force that is in our every movement and has been performed in nightclubs, festivals and conferences in the UK, North America and Australia. To see a video of one iPoi performance, click here.
Poi is an ancient Maori art (see homeofpoi.com). Poi are simply balls (poi is a Maori word for ball) attached to chains or cords that are held in each hand and swung around the body in circular movements to create both simple and complex patterns in the air and around the dancer. In Maori culture they were originally constructed with a small rock on the end of a flaxen cord and were traditionally used by men and women to improve flexibility, strength and co-ordination for both work and war. These attributes make poi a particularly interesting object to use as an exertion interface in that they encourage really physical activity on the part of the performer. Today poi are popular objects adorned with tails and ribbons that glow in the dark or can be fixed with tiny flashing lights and are regularly used at clubs and festivals as a means for clubbers, or ‘poiers’, to gain access to and merge with the driving 4/4 beat of techno and trance music within the dance space. Like juggling, the physics of poi can be attributed to momentum, gravity, centripetal forces and acceleration. Small circular hand movements and wrist rotations are amplified at the end of the cord and thus the momentum and impact is increased creating a dynamic and fluid visual display. The figure above shows our poi expert Matt Cooper performing the Butterfly, a basic poi pattern.
By embedding a traditional set of poi with wireless technology we aimed to augment this amplification still further so that the relationship between the performer (the poier), the performed object (the poi) and its performance output (physical, visual and auditory manifestations) was extended and stretched to capacity. As swinging poi is generally a solitary activity and poiers regularly claim they are unaware of people watching them dance, we wanted to investigate how external manifestation of the object’s movement through space could influence and increase the desire to interact with others and with the aesthetic environment created as a direct result of the poi’s flight. We call our system iPoi.
iPoi is not a game, but rather a dance with a low entry fee that encourages spontaneous improvisation (Paidia, pure play). Multiple participants improvise their own version of the ancient dance through a demonstration of their traditional poi skills which are then fed back to the audience through realtime visual and sonic output. iPoi has no winners but rather it encourages people to teach, learn and share skills through watching and participating in a performance.
Prototypes: Wired and Wireless
Wired Prototype
Our first consideration was to understand the affordance of our chosen object and how we could use affordance in our design. Poi affords, among other actions, swinging. The action of swinging is based on momentum and basic gravitational pull. To better understand momentum and basic gravitational pull, our first step was to attach a sensor on the object itself (the poi ball) in order to read data from a swinging poi. We determined that we required a sensor that was small and lightweight enough so as not to interfere with the action of swinging yet complex enough to provide us with detailed sensor readings. We chose an accelerometer (for a discussion of why we chose to use an accelerometer, see (publications Bayliss 2005; Sheridan 2006). Attaching an accelerometer to poi allowed us to collect data from the swinging poi in realtime and helped us to understand the effects of momentum and gravitational pull. We could and then turn this data into a readable form for analysis.
We glued the accelerometer directly on to the surface of the poi. The accelerometer was directly wired to a Smart-It sensor board. The Smart-It was fitted with a PIC micro-controller which allowed us to store and run acustomized program for reading acceleration data. The Smart-It was then attached to a MIDI interface and the MIDI interface was attached to a PC via a serial cable (Figure 1). We ran our customized program the Smart-It, and collected streaming acceleration data from the accelerometer. As we swung the poi in the air, we could then see the acceleration changing on the PC screen. We streamed the MIDI data through GarageBand to hear the audio output.
The figure above shows the configuration of wired poi prototype with attached accelerometer. As the poier swings poi around their body the accelerometer sends the acceleration data in realtime to the Smart-It over a wired connection. The Smart-It converts the data to MIDI notes which are then read by the MIDI interface. The MIDI notes are sent from the MIDI interface to a music instrument which can read MIDI or to a PC. The MIDI notes are then read in any program on the PC which can read MIDI such as Garageband. So as the poier swings the poi, he creates musical notes or controls video.
Whilst the data transmission and accelerometer worked fine for translating acceleration data into musical notes, the awkwardness of the wires meant that the poi object limited the poier's freedom of movement. In other words, our witting poier was limited as to how he could really perform – the poi object restricted performative behaviour rather than encourage it. We determined that if we wanted to allow for witting performance our next prototyping phase had to focus on realizing wireless data transmission between the poi objects and the PC.
Wireless Prototype: Single Channel
Our development goal for our second prototype was to allow poiers multiple degrees of freedom and non-restricted movement. To do this, we required a wireless interface. For our second prototype system we custom designed a sensor board with an attached accelerometer that was small enough to fit inside a poi ball (figure to right). Our design was purposely simple and included our original accelerometer, a radio transmitter for wirelessly transmitting data from the poi to the Smart-It, a PIC microcontroller containing the poi code, a 3V Lithium-Ion flat battery, and two LEDs for indicating when the poi was on and when it was transmitting data.
The figure below shows our custom-designed iPoi board and configuration of first wireless prototype. Poi is embedded with a round sensor board with an attached accelerometer. Acceleration data is transmitted wirelessly to the Smart-It. The Smart-It translates the acceleration data to MIDI notes which are read by the MIDI controller and sent to the PC via a wired connection. The poier swings the poi with multiple degrees of freedom of movement and the acceleration data is translated into musical notes or controls visual output.
The figure below shows the in-situ set up for the guerilla performance we performedd in a nightclub. One performer and one VJ agreed to perform at the beginning of the evening. The VJ’s job was to map the poi acceleration data to various visual effects, such as `scrub' and `rotate', using a VJ software tool. As the poier performed various moves, the visuals would change based on which visual effect the VJ had chosen. The acceleration data changed the speed of the effect. So if the VJ selected ‘rotote image’ then as the poier swung poi, the image would rotate faster or slower depending on how fast the poier was swinging the poi. The VJ varied the effects depending on the response of the people observing the performance and the response from the poier.
Wireless Prototype: Multi-channel
Our intention with the prototyping phase of the project was to augment poi so as to facilitate witting transitions in performative behaviour. We describe our earlier prototypes in [see publications] which examined how each prototyped object worked closer to our goal of facilitating witting transitions.
Both our wired and first wireless prototypes certainly encouraged witting performance to some extent. However, the limitations of both of the systems meant that we could only transmit data on a single channel; only one poier and one poi ball could be used at any one time. This limitation meant that the data flow was transmitting from one poi ball only and therefore captured data from one poi in motion (in other words, half of the poi pattern being performed). To detect full poi patterns, we required a system that would allow us to collect data from both poi in realtime.
Our final prototype focused on allowing multiple users to mutually engage (Bryan-Kinns et al., 2007) with each other using poi to create one communal, dynamic sound and visual piece. Bryan-Kinns et al. define mutual engagement as ‘the points at which people spark together, lose themselves in their joint action, and arrive together at a point of co-action’. This meant that we needed to extend our wireless interface to allow for multi-channel data transmission (ie. transmitting signals from multiple poi simultaneously). The Mote board provided this interface (moteiv.com).
The Mote (above left) itself is placed in a long sock (left) and swung around the body. Acceleration data from the swinging iPoi is transmitted to a base Mote attached to a PC. The data is then wirelessly transmitted to another PC where it is used to create visual imagery and audio soundscapes. The system we developed is dynamically reconfigurable allowing us to connect several iPoi and computers on the fly to create ad-hoc installations e.g. allowing DJs and VJs to interact with the data from the swinging iPoi. See configuration image below.
To perform iPoi, the installation had three basic components: sets of poi embedded with Motes, three computers, and projector facilities. We describe one performance in detail here. The event took place in a location which usually functioned as a dance studio - a large rectangular room with tall windows down one length of the room and at one end, mirrors along one end and a balcony (Figure below). As there was no method of attaching a projector to the ceiling, we had to fix our projector on a large stepladder in the middle of the room which was covered the ladder with black cloth.
From our earlier guerilla performance, we recognized that not everyone is comfortable performing in front of groups of people and that sometimes the expert poier made the system look difficult to use. To address this issue, we secreted a Mote inside a small teddy bear (See figure right). The teddy bear afforded the action of shaking, a subtler movement and a rather more inconspicuous object than the iPoi (right) .
We used three computers to control the audio and visual elements. One computer collected the realtime data wirelessly from the Motes. This data was then sent wirelessly to the audio application running on another computer. Both of these computers sat in the far corner of the room underneath the balcony in a metal box. Our third computer sat underneath the projector on the ladder in the middle of the room. This computer, which ran our visual output, was connected to the projector. The projector then cast the resultant image onto a white wall. To create a more defined performance space within what was otherwise an empty room with no lighting to direct focus or delineate particular areas, we placed several iPoi on a plinth between the projector and the projection wall.
Each iPoi had the capacity to trigger one set of pre-recorded audio samples and one pre-made visual. So swinging one iPoi would contribute to both a soundscape and an image layered over the top of the background image and sound. Swinging several iPoi would create additional layers in much the same way as a DJ or VJ might layer tracks and images over each other to create an individual interpretation of the raw materials available. For this particular installation one iPoi controlled a digital animation of a shadow puppet dog on the left hand side of the screen. The longer a performer swung the iPoi, the further the dog would move towards the middle of the projection screen. A different iPoi controlled a similar dog on the right hand side, another controlled random words and a fourth created a real time plot of acceleration data on the bottom of the screen. (Important to note is that the sounds and visuals did not cancel each other out – images and visuals were calibrated so that they complemented each other to create one coherent layered soundscape and visual projection.)
Two soundscapes (referred to as fx and dog music) were created for the piece and played using Ableton Live (http://www.ableton.com). Each consisted of a continuously playing loop of five structured musical tracks which were selectively activated by the objects when they moved, and one track which continuously played a simple heartbeat. Both soundscapes had a dance/techno feel and played at 120bpm (although fx had a softer, more organic quality than dog music). The audio soundscapes were changed half way through the evening so that the performance stayed engaging and fresh.
iPoi Publications
Sheridan, J.G., Bryan-Kinns, N. and Baylss, A. (2007). Encouraging Witting Participation and Performance in Digital Live Art. 21st British HCI Group Annual Conference, 3-7 September, Lancaster, UK. [PDF]
Bryan-Kinns, N. and Sheridan, J. (2007) Supporting Mutual Engagement in Creative Collaboration. Workshop on Tools in Support of Creative Collaboration, 6th Creativity and Cognition Conference, 13 June, Washington, USA. [PDF]
Sheridan, J.G., Bayliss, A. and Bryan-Kinns, N. (2007). The interior life of iPoi: objects that entice witting transitions in performative behaviour. International Journal of Performance Arts and Digital Media 3(2). Intellect: Bristol.
Sheridan, J., Bayliss, A. and Bryan-Kinns, N. (2006). iPoi: acceleration as a medium for digital live art. Demonstration. The 8th International Conference on Ubiquitous Computing, 19 September, Orange County California, USA. [PDF]
Sheridan, J.G., Bayliss, A. and Bryan-Kinns, N. (2006). iPOI. In Proceedings of the First International Symposium on Culture, Creativity and Interaction Design, 12 September, Queen Mary, University of London, UK. [PDF]
Sheridan, J.G. (2006) Digital Live Art: Mediating Wittingness in Playful Arenas, PhD Thesis, Computing Department, Lancaster University, UK.
Bayliss, A. and Sheridan, J.G. (2006) Collaborative Clubland: Performing Ubiquity, Mindplay Conference on Digital Media Theory, Culture, Practice and Play, 20 January 2006, London Metropolitan University, UK.
Bayliss, A., Sheridan, J.G., and Villar, N. (2005) New Shapes on the Dancefloor: Influencing ambient sound and vision with computationally-augmented poi. International Journal of Performance Arts and Digital Media 1(1). Intellect: Bristol, pp. 67-82.
Appearances: Demos and Performances
matterealities, mobilities, innovation, 5 November 2007, Nuffield Theatre, Lancaster UK.
(re)Actor2, 10 September 2007, Leeds UK.
SolFest, 24-26 August 2007, Cumbria UK.
Microsoft, 20 August 2007, Cambridge UK.
Planet Angel, 10 August 2007, London UK.
Wickerman Festival, 20-22 July 2007, Dundrennan, Scotland.
Beat Herder, 29 June - 1 July 2007, Ribble Valley, Lancashire UK. Cancelled due to torrential downpour/loss of electricity!
Emergent Objects, 7th June 2007, Design for the 21st Century, Leeds University, Leeds, UK. Emergent Objects
Sunrise Celebration, 31 May - 4 June 2007, Somerset UK.
Our development goal for our second prototype was to allow poiers multiple degrees of freedom and non-restricted movement. To do this, we required a wireless interface. For our second prototype system we custom designed a sensor board with an attached accelerometer that was small enough to fit inside a poi ball (figure to right). Our design was purposely simple and included our original accelerometer, a radio transmitter for wirelessly transmitting data from the poi to the Smart-It, a PIC microcontroller containing the poi code, a 3V Lithium-Ion flat battery, and two LEDs for indicating when the poi was on and when it was transmitting data.
Our intention with the prototyping phase of the project was to augment poi so as to facilitate witting transitions in performative behaviour. We describe our earlier prototypes in [see publications] which examined how each prototyped object worked closer to our goal of facilitating witting transitions.
Our final prototype focused on allowing multiple users to mutually engage (Bryan-Kinns et al., 2007) with each other using poi to create one communal, dynamic sound and visual piece. Bryan-Kinns et al. define mutual engagement as ‘the points at which people spark together, lose themselves in their joint action, and arrive together at a point of co-action’. This meant that we needed to extend our wireless interface to allow for multi-channel data transmission (ie. transmitting signals from multiple poi simultaneously). The Mote board provided this interface (moteiv.com).
We used three computers to control the audio and visual elements. One computer collected the realtime data wirelessly from the Motes. This data was then sent wirelessly to the audio application running on another computer. Both of these computers sat in the far corner of the room underneath the balcony in a metal box. Our third computer sat underneath the projector on the ladder in the middle of the room. This computer, which ran our visual output, was connected to the projector. The projector then cast the resultant image onto a white wall. To create a more defined performance space within what was otherwise an empty room with no lighting to direct focus or delineate particular areas, we placed several iPoi on a plinth between the projector and the projection wall.