"A Nervous System Model for Direct Dynamics Animation" Direct dynamics animation consists of synthesizing the movements of a model from the More

"A Nervous System Model for Direct Dynamics Animation" Direct dynamics animation consists of synthesizing the movements of a model from the specification of its physical properties (mass and moment of inertia), the conditions of bond between its contracting parties, the conditions of contact with other bodies and the forces that acts on it. This approaching has the advantage to generate animations with physical realism. The problem, that continues relevant as inquiry object, is the control of the model: "What forces must be applied to the model to generate the desired movement?". The solution of the problem, presented in this work, assumes that the studied model consists of a structure of rigid link bodies whose movements are generated by internal actuators, with its forces defined by a nervous system. With use of artificial neural networks and evolutionary computation, the proposed controller is capable of adapting itself to control different articulated models, and to generate varied types of movements while it keeps the stability even with small variations of the terrain. The presented model possesses, in its core, a Central Pattern Generator (CPG) based on neural oscillators, that has their activities regulated by the sensorial module, to allow the balance of the structure and stability of the movement, responding to environment variations. For the adaptation to the articulated structure and learning of movements, the controller has a cognitive module, responsible for the search of neural parameters, through genetic algorithms, and the feedback networks (sensorial answers to environment variations), with genetic programming. Results are presented related to the control of models humanoid, cheetah, frog, luxo and luxo-2, having these last two ones equal topologies, but with variations in the sizes of the bodies and freedom of the joints. All the models are tested in plain land and with slope. ODE (http://www.ode.org/) was used to physical simulation.
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'A Study Of Wave Phenomenon' 'A Study of Wave Phenomenon' consists of a four foot high console adorned with 26 illuminated More

'A Study Of Wave Phenomenon' 'A Study of Wave Phenomenon' consists of a four foot high console adorned with 26 illuminated buttons and a joystick. Controlled by the console is a dynamic system consisting of a modern apple macintosh computer, a television monitor, a pair of stereo speakers and an active subwoofer with a small circular metal vibrating plate attached to it which is filled with a thin layer of black ink. A television monitor is positioned to reflect the image on its screen into the ink, a digital video camera in turn films this reflection. The monitor, camera and subwoofer are housed within a unit where the vibrating plate and its ink layer can be observed. Sound output can be selected in a random way using the joystick from a selection of many audio samples rescued from chance and improvised recordings of cheap electronic toys, keyboards (some of which have been hacked into and re wired ) and old 8 bit video games that have been scrambled using trial and error coding. Sound output can also be selected in a predictable way using the blue button bank to select from a series of different frequencies and waveforms the amplitude of which can be adjusted using the joystick. It is important to note that all the functions of the console controls must be discovered by the user, the more time spent playing will result in more of an understanding of the nature of the system and it's interface There are two banks of buttons positioned either side of the joystick, one for initiating a random selection of an image or animation and one for initiating a random selection from a bank of short video loops. These are reflected and filmed live from the surface of the ink and the whole 'mix' is back projected onto a screen in front of the console. The resulting effect is one of being able, through dynamic feedback reliant on user input to experience the direct physical, visual effect of sound upon a liquid. Combined with connected self similar imagery and logical human technologies, from snowflakes, brain slices and video feedback to digital technologies and binary, scrambled video game graphics, automated systems and logical scientific models. The realization, within the consciousness of the user, of being in full control of some aspects of the system and only being able to initiate influence on other parts highlights harmony between order and chaos whilst hopefully raising questions about the viability of mutually exclusive oppositions and separation prevalent in much western thinking and language. The title of the piece pays homage to the life's work of Hans Jenny and his experiments with the effects of sound upon matter. His book is entitled 'Cymatics', A Study of Wave Phenomenon'. The work contained within this book along with the pioneering acoustical work of Ernst Chladni have been a vital source of reference and inspiration in the conception of this work.
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