Title
Artists




Perversely Interactive System
Lynn Hughes and Simon Laroche
METABOLISM
Synopsis

Perversely Interactive System is an installation which puts the spectator- participant into relation with a virtual other whose image (s)he controls through a biofeedback device.

The piece consists of a large scale video projection and a wireless biofeedback handset that measures galvanic skin resistance (variation in sweat gland activity). A reduction in galvanic skin resistance occurs as a result of the lowering of levels of internal stress which are accompanied by physiological reactions such as muscle tension. These reactions are normally regulated by the autonomic nervous system but an individual can learn to control them by relaxation techniques such as breathing, meditation, visualization etc.

The video projection begins with the image of a woman with her back turned. As the participant learns to reduce his or her stress / sweat level this causes the image of the woman in the video to turn around, and advance (hesitantly) towards the participant.

In Perversely Interactive System we were interested in the symmetry, and the engagement, between the image of the person on the screen and the individual in front of the screen. The fact that the person on the screen is controlled by the body functions of the participant sets up a kind of empathy, an intimacy. At the same time the virtual other remains fugitive and difficult to control . (It is worth noting that this piece functions psychologically rather differently depending on whether the participant is male or female).

Technical
specifications

A PC computer connected to a midi interface and then to a wireless radio receiver controls the projector, the sound system and the image on the screen. The software used is Pure Data* (Pd) an open source graphical music software very similar to the MAX software for the MAC. The receiver receives data from a wireless handset and transmits it to the Pd program which analyses the data and causes the image of the woman on the screen to start, continue or pause based on an average of a short series of readings. At the same time the sound system receives instructions from a Pd sound modulation patch. The sound used is a simple, visceral low tone that increases/ decreases in frequency with each (non-averaged) reading received from the handset and provides the user with a continuous sense of what is happening in his/her body.

The Pd programming controls an avi file of video footage of a woman walking towards the camera from about 30 feet in the distance so that, when the average readings indicate a lowering in tension over a short period of time the woman advances. She will advance a few steps to a predetermined “pause” place. If the readings continue to remain low or drop she will then advance to the next pause. If the participant’s tension level rises (often due to the excitement of success) then the woman waits. The image of the woman can be made to advance until she is standing life size in front of the participant. When the handset is released the image gradually fades and then reappears at the starting point where the woman is in the distance with her back turned.

The image is projected on a custom rear projection screen that mimics the proportions of the figure. It has no frame and is suspended via a Plexiglas rod inserted in a tube sewn into the top border of the projection material. The handset casing was produced by rapid-prototyping. It is plastic and incorporates two metal bands for the finger contact that delivers the skin readings.

*also described at http://crca.ucsd.edu/~msp/Pd_documentation/
as “a patchable environment for audio analysis, synthesis, and processing, with a rich set of multimedia capabilities” written by Miller S. Puckette who also wrote MAX for the Mac.

Hardware:
PC, video card, sound card, Midi-man midi interface + long midi cables, projector, pair of speakers with subwoofer, biofeedback handset adapted from Thought Technologies basic GSR with added… wireless transmitter and receiver.

Software:
Pure-Data

  
Schemes
and pictures




 
Video
Assessment This piece was intended to offer a relatively intimate and implicating experience of a relation to a virtual other. Everything was kept as simple and stripped down as possible so that the focus remained on the effort to get the virtual woman to respond -rather than on narrative or distractingly metaphorical elements.

The installation worked very well at Dare-Dare. The screen was suspended in the middle of the gallery and seemed to float in the darkened space adding to the feeling of ephemerality or virtuality of the image. The screen also functioned equally well from either side and the fact that the woman walked towards one even when from “behind” the screen contributed to the eerie feeling set up by the image and screen. Except for the sound system wiring, almost all the wiring was taped up so that it was not in evidence and the computer was also concealed. Again, these details reinforced the simplicity of the installation and the sense of mystery implicit in the type of interaction and image.

The receiver was taped to a pipe directly over the screen and the reception was excellent from anywhere in the space so that the participant could really walk freely around the space and the image while interacting.

The system was very robust and there were no real problems or bugs during the four days it was presented.

The weakest element of the piece was the physical appearance of the handheld interface. The design was too close to a computer mouse or the equally familiar remote control handset and as a result people tried to use it in inappropriate ways. A second design has since been elaborated which avoids these connotations and is more intuitive to use although it may still be useful to provide some visual explanation of how to hold and use the interface.

In fact one of the most interesting conclusions that we came to after showing this prototype was that complete lack of instructions or explanation is not only rarely practical but also is not always desirable for other reasons. In the case of this piece, the interaction was only really meaningful and involving when participants knew that it was their stress level that controlled the image. This set up the desired situation where wanting to succeed was likely to made it all the more difficult –where getting what one desired required controlling or denying that desire.