Digital human modeling capabilities for task-based survivability

Although modeling and simulation are fertile areas for research and development within medicine, education, and human factors, there is a growing need for fully integrated organ systems as part of any digital human model (DHM). This need is particularly high in task-based survivability assessment. However, the current static geometry used in DHM is insufficient for evaluating conditions during simulated task performance. This insufficiency is due to the fact that internal viscera are inherently non-rigid objects. Therefore, undesirable, and unrealistic behaviors occur when using static models to represent internal viscera as the DHM moves through a variety of postures.

The capacity for DHMs to take on a variety of postures and positions contributes to their overall usefulness in modeling and simulation. By using static models to represent internal viscera, errors in model behavior must be tolerated, or the DHM must be limited to a posture that matches the models’ configurations. With the either option being undesirable there is a need to represent internal viscera using dynamic models. A dynamic model will allow for the geometry used in representing the internal viscera to deform as the DHM.

Thus this work proposes a computational platform for controlling the motion and deformation of internal viscera models within a DHM. This platform consists of two components. The first component is a new method for maintaining a relative position within a dynamic character’s mesh called skin-based parenting. The second component is a system which takes a free-from deformation technique used in artistic modeling and eliminates the manual input that is usually required. This platform produces representations of internal viscera which conform to the character’s posture in real-time at an interactive rate. Thus enabling the assessment of how particular environmental influences relate to the position and orientation of internal viscera models within a DHM in a variety of postures.