Simulating how the human body deforms in contact with external objects, tight clothing, or other humans is of central importance to many fields. Despite great advances in numerical methods, the material properties required to accurately simulate the body of a real human have been sorely lacking. Here we show that mechanical properties of the human body can be directly measured using a novel hand-held device. We describe a complete pipeline for measurement, modeling, parameter estimation, and simulation using the finite element method. We introduce a phenomenological model (the sliding thick skin model) that is effective for both simulation and parameter estimation. Our data also provide new insights into how the human body actually behaves. The methods described here can be used to create personalized models of an individual human or of a population. Consequently, our methods have many potential applications in computer animation, product design, e-commerce, and medicine.

We describe the first end-to-end system, called VitalFit, for predicting the fit of close-to-body garments using soft body avatars. Soft body avatars may be constructed by registering our VitalBody template to existing rigid avatars, or directly to 3D body scans. The resulting soft avatar includes a tetrahedral mesh and soft tissue material properties that may be numerically simulated using the finite element method (FEM). Designers, fit specialists, and pattern engineers may create virtual garments and evaluate fit using VitalFit DX, a plugin for Adobe Illustrator®. Users can import existing patterns or create them anew, and modify the patterns using the familiar tools in Adobe Illustrator®. In VitalFit the garment and body are simulated together, with two-way coupling of forces and displacements. This allows us to predict how human soft tissues deform in contact with the garment. We can also predict stresses and strains in both garment and body. VitalFit can simulate the coupled dynamics of soft tissues and garment, during running and other activities of daily living. These new tools can be used to predict not only static fit, but also how a garment may function in real life.