ABSTRACT
This paper presents an efficient dynamics-based computer animation system for simulating and controlling the motion of articulated figures. A non-trivial extension of Featherstone's O(n) recursive forward dynamics algorithm is derived which allows enforcing one or more constraints on the animated figures. We demonstrate how the constraint force evaluation algorithm we have developed makes it possible to simulate collisions between articulated figures, to compute the results of impulsive forces, to enforce joint limits, to model closed kinematic loops, and to robustly control motion at interactive rates. Particular care has been taken to make the algorithm not only fast, but also easy to implement and use. To better illustrate how the constraint force evaluation algorithm works, we provide pseudocode for its major components. Additionally, we analyze its computational complexity and finally we present examples demonstrating how our system has been used to generate interactive, physically correct complex motion with small user effort.
Subject(s)
Acceleration , Algorithms , Computer Graphics , Computer Simulation , Locomotion/physiology , Models, Anatomic , Biomechanical Phenomena , Humans , Imaging, Three-Dimensional , JointsABSTRACT
The MediSim system extends virtual environment technology to allow medical personnel to interact with and train on simulated casualties. The casualty model employs a three-dimensional animated human body that displays appropriate physical and behavioral responses to injury and/or treatment. Medical corpsmen behaviors were developed to allow the actions of simulated medical personnel to conform to both military practice and medical protocols during patient assessment and stabilization. A trainee may initiate medic actions through a mouse and menu interface; a VR interface has also been created by Stansfield's research group at Sandia National Labs.
