MIMESIS : An interactive tool for movement synthesis

MIMESIS is an interactive modeling environment developed by ACROE, which allows any user to build their own physical models to generate movements. These models are built with CORDIS-ANIMA, a modeling language that implements the basic principles of Physics through networks of simple modules: inertia, interactions, Newtons’s third law.

 

Key features

MIMESIS is different from usual modeling environments used in computer graphis and animation because it doesn’t focus on shape, but on movement and on the model that generates it. Consequently, an essential property of MIMESIS is that fact it is not used to model objects, but to model behaviors. The idea of “object”, which is predominant in shape modelers, is completely replaced by the idea of “network”: a model is a network of connected CORDIS-ANIMA modules.

In MIMESIS, the user defines and manipulates very varied and possibly complex physical networks, ranging from highly structured models of puppets, vehicles, etc., to large homogeneous networks used to model materials (sands, pastes, …), and from a dozen of physical modules to tens of thousands. But the richness of dynamic effects obtained is also linked to the fact that, even with few physical modules, the different subparts of a model are interdependent through the bidirectional physical interactions, which creates complex emerging couplings.

Structure of the environment

MIMESIS allows creators to work at the lowest level of physical models and doesn’t hide the fundamental principles of the technology used. It results from this approach a complete freedom to build models, by manipulating directly the inertia and interaction modules that constitute the networks, which makes MIMESIS not only a modeling tool, but a creative tool. This choice also has the advantage to bring the user to enact and understand the fundamental philosophical concepts of the system.

Modeling language

 

 

 

The MIMESIS environment includes a scripting language to create and manipulate the physical networks. The last version is called PNSL (Physical Network Scripting Language). It has been designed so as to be as generic as possible and to address all modeling activities allowed by CORDIS-ANIMA, such as creating, labeling and connecting modules.

 

 

 

 

 

 

 

 

 

How does MIMESIS allow to create all kinds of dynamic effects ?

The concepts described above and offered to any user through MIMESIS support properties that are required in a creative tool dedicated to generation of visual movement.

Firstly, creating movement is all about searching for an organic link between time and space. For this purpose, the notions of “intensive” and “extensive” physical variables are really helpful. This is why they are explicit in the formalism. Space is intimately linked to extensive variables, such as position, displacement and speed. The concept of force allows to implicitly link these variables in time, through difference equations. Therefore, far beyond modeling as it is conventionally thought of in animation software where a shape is first built then put in motion, or in motion capture systems in which a movement is performed and then associated to a shape, there is no opposition here between space and time.

This formalism has at least three of the well-known properties of a network and that are essential for any creation tool: genericity, modularity, and consistency of the model during its construction by the user. The first property of modularity is expressed by being able to build a model step by step, by increasing its complexity, differently from the usual equational formulation that must immediately be complete. This property is fundamental for creating a tool, which will allow any user to make what they want by joining – or composing - components.

The second property of genericity is expressed by the fact that the combination of elementary behavior leads to a "networks" approach, which is known to allow modeling a wide variety of dynamical behaviors. This second property is also essential for a creation tool, since the artistic activity aims to create new effects and therefore cannot be restricted to a predefined set of effects.

The third property is that when building a network, the user does not manipulate equations. However, the syntax of modules handled by the user guarantees that they always build a physically coherent network without having to worry about it. The user is thus relieved of both formulating equations and managing the physical consistency of these equations. This property is essential since the artistic activity necessarily contains a phase of intense focus on desired effects rather than their mathematical or computational implementation.

These three principles allowed to generate a wide range of dynamic effects with a single formalism and a single type of expertise (some examples are given below): muscles, articulated rigid bodies, deformable, turbulences, fractures, biological cells, avalanches, pastes, crowds, or dance movements.

 


Various versions of MIMESIS are available for trial or sale : see Products