Claude Lacoursičre, Chief Technical Officer CMLabs Simulations Inc. Montreál, Qc, Canada

After college studies in music performance and initial university studies in biochemistry, Claude joined the physics department of McGill University where he received an Honors Undergraduate degree and a Master's degree. He was then working on computer simulations of first order phase transitions. After some PhD work with at the Center for Nonlinear Dynamics in Physiology and Medicine of McGill University where he developped physics based simulations of physiological systems and published a few papers, he joined Lateral Logic in 1996, a startup founded by former colleagues from the undergraduate physics program. Though the company has changed name twice since, he has consistently worked on developing physics simulation software for virtual reality applications such as heavy vehicle operator training, virtual engineering, games, robot control, intelligent systems and medicine. His work has primarily focused on rigid multibody dynamics with contact and friction, with special attention to heavy vehicles. Since February 2001, Claude is the CTO of CMLabs Simulation Inc. and continues his work on physics modeling and numerical methods development.

Seminar 1:
Time: Thursday Jan 31 2002 at 15.15
Location: MA156, MIT building

Simulation of Rigid Multibody Dynamics for Virtual Environment.

Virtual Environments using interactive 3D graphics as their main components have proved their effectiveness in simulation training, rapid prototyping and entertainment over the years. As visual realism has improved greatly both in quality and availability, behavioral realism is becoming increasingly important. Given the degree of realism of the objects seen in virtual environments today, users expect their movement and behavior to beequally realistic. This requires the interactive simulation of the laws of physics which can be used in a variety of ways to bring realism to virtual scenes.

Since many 3D environments are composed of rigid geometric objects, it is only natural to concentrate first on simulation of rigid multibody physics with contact and friction. This involves a mixture of geometric interference detection (also known as collision detection), contact physics and the physics of assemblies of rigid bodies with kinematic constraints. I will review the computational problems linked with both geometric interference detection and those linked with the non-smooth dynamics of contact physics. In particular, I will review several forumaltions of the contact dynamics equations and their solution methods.

Seminar 2:
Time: Fridag Feb 1 2002 at 11.00
Location: CS conference room, MIT building.

Potential for Parallelisation of Interactive Physics Based Simulations

In the quest for more and more realistic Virtual Environments which
integrate 3D graphics, sound, haptics and motion subsystems, interactive
simulation of physics has proven to be a very useful tool. However, the
computational problems being addressed are very challenging and given the
hard limits imposed on the basic refresh rate of any interactive
simulation, parallelisation is an interesting avenue to explore. However,
the challenges being faced here are rather different in nature from the
typical cases which have been studied so far in parallel computing. I will
address the main issues in parallelisation namely, going from the main
simulation loop down to the linear algebra subproblems and explore
potential for parallelisation at every stage. In particular, I will
address the issues of task parallelism between geometry and phyics, domain
decomposition and recombination for coupling of sub-systems.

This is an informal and exploratory talk intended to stimulate interest.
No hard experimental results will be presented.

email: claude.lacoursiere@cm-labs.com

Visit the CMLab Simulations web site.