Human Modeling – From Bubblemen to Skeletons 2001-01-2086
This paper introduces a novel human modeling system utilizing the ADAMS (Mechanical Dynamics Inc.) multi-body simulation program. The FIGURE Human Modeling system is a plug-in to ADAMS, which provides users with the capability to generate human models of various levels of detail and fidelity, permitting simulations ranging from passive response (crash, falls, etc.) to active participation (sports performance, task simulation).
One of the major innovations of FIGURE is how human motion is simulated using a concept of “motion agents”. Motion agents are parts, which are positioned on the body segments at the location of the motion target marker from the motion, capture system. The motion agent is attached to the body part with a 6 degree-of-freedom spring so as to be a “motion influencer” rather than a “motion governor”. Data from the motion capture system drives the agents thereby driving the human model. Since the human model is physics-based, the model will not violate joint restrictions, environment contacts, etc. From this simulation, resulting muscle elongation histories are then captured. A second simulation is performed using these muscle elongation histories via proportional derivative (PD) controllers to drive the human model using a direct dynamics approach.
The paper introduces the modeling paradigm of FIGURE and provides an example of direct dynamics simulation based on data from a newly introduced motion capture device.