Research: Rigid-body Mechanics

Featured Research: Rigid-body Mechanics

Loomis, Balkcom, Trinkle, and Gottlieb

Rigid-body models are fundamental to almost all algorithms for physical simulation, planning, and control. Even flexible objects are often modelled as collections of rigid bodies loosely joined by springs. As with all models, however, rigid bodies do not capture all desirable characteristics of the physical system. The solutions to rigid-body dynamics equations with Coulomb friction may be inconsistent, or indeterminate. Efficiency is also a concern -- computing the solutions to the dynamics equations in the inner loop of a design or control algortihm is expensive.

Balkcom, Trinkle, and Gottlieb designed an algorithm for computing all possible forces and torques consistent with constraints on the motion of rigid bodies, and used the algorithm to compute parts-seating plans that are robust to incomplete or incorrect sensor information and to frictional indeterminacy. More recently, Loomis and Balkcom have explored methods for efficiently computing manipulation plans for unstacking piles of objects by exploiting the similarity between the dynamics computations at different stages of the disassembly.

Rigid-body Mechanics