The SICIB (Sistema Interactivo de Composicion e Improvisacion para Bailarines) is a computer system based on the use of sensors for interactive music composition. The system allows to obtain musical information by tracing body movement of dancers.
Brief history – SICIB (Sistema Interactivo de Composicion e Improvisacion para Bailarines) was developed through a working group of the Multimedia Centre (CN) of the Centro Nacional de las Artes (CNA) of Mexico City during the early 2000’s. This is a computer system can extract information from body movement to generate data control or synthetic sounds. It can be seen, in effect, as a technological music instrument technology designed to give new possibilities to composers, respect to production of multimedia works.
Historical antecedent – The work on SICIB born within a context established. Firstly, the authors draw on the experiences, in the mid-sixties, by John Cage, David Tudor and Merce Cunningham. From this collaboration was born Variations V (1965), a multimedia work in which dancers could trigger playback of sounds moving between the photoelectric cells placed within the operating area. Although it was not conceived as a computer music composition, Variations V has revolutionized the concept of the relationship between the composer and choreographic elements of dance.
Models computer reference – Besides the experience of Cage, Tudor, and Cunningham, lie other experiences oriented, this time, towards the use of computers. This provide to SICIB’s researchers, reference models. Among these is worth remembering the BigEye of STEIM in Amsterdam (STudio voor Elektro-Instrumental Muziek) or CONTROL SUIT of NoTAM (Norwegian Network for Technology, Acoustics and Music).
The conceptual model – To develop SICIB, the researchers began with the analysis of the common elements to dance and music. With this approach have identified certain characteristics: exposition of ideas, links and transitions between the different sections of a general structure, problems of form, variations and embellishments.
Technological equipment – Once identified these common elements, it was to formalize and give substance to a system that was able to really put in relation two different artistic expressions. To achieve this goal, was defined use of computer and motion sensors. To these are added software for information management and manipulation.
Sensors – The SICIB has been equipped with sensors capable of recording information of movement of dancers. Were used Flock of Birds, of the Ascension Techonology Corporation (www.ascension-tech.com), technically known as motion trackers, developed for medical purposes. These sensors, once placed on body, were able to return information according to the axes x, y and z, registering about 144 measurements per second within a radius of about 4 meters from a central transmitter. The sensors are connected via serial to a computer dedicated to recording data, should provide specific information with respect to the curvature and torsion of the body, position them in space, movement speed, acceleration and sudden changes of direction. Torsion and curvature information were obtained through an application of theorem by Frenet-Serret.
Management software – The operation of SICIB is related to the use of two software: Escamol and Aura. The first is a useful language to create musical scores made in reference to grammatical rules. Realized in Prolog, was equipped with an interface written in Tcl/Tk. Body movement information allowed Escamol to generate MIDI output or in Aura and Csound format. Aura, however, is a object-oriented language designed for the creation of virtual synthesizers and synthesis algorithms. Aura textual approach also allowed the real-time control and manipulation of musical parameters. Aura, SICIB and Escamol are interfaced through UNIX pipeline communication.
Control interface – The control of the entire system, then, was through an interface realized in Tcl/Tk. Through this, the user can execute several tasks: get in a Prolog environment to define conditional rules (If-Then), start Escamol, Aura or Csound, launch an application written in C and designed for the filtering of information from sensors. The latter was able to perform different functions: in particular was designed to manage the link between sensors and computer (a Silicon Graphics workstation), filter the information received and add timing information to the data received.
Defining parameter – Beyond the technical aspects, the SICIB required the definition of a very detailed work plan. In fact it was very important to establish, from the start, what kind of information recorded by each sensor, then determine what kind of musical parameter combine to each movement recorded. All of this was defined by a system of rules of Condition/Action (If-Then) developed in Prolog environment. The rules set out, could be saved by giving origin to a library useful in subsequent work. More rules could be applied to a single sensor, as well as more sensors could be affected by a single rule. The system of rules could be activated or deactivated at any time of the performance.
For this topic I’ve read:
 Roberto Morales-Manzanares, Eduardo Morales, Roger Dannenberg, Jonathan Berger, SICIB: An Interactive Music Composition System Using Body Movements, Computer Music Journal, Vol. 25 , 2001.