The AnyMoCap Framework

The AnyMoCap model is an effort to create a simple and unified framework for doing any kind of mocap analysis with the AnyBody Modeling System.

../_images/anymocap.jpg

Features

  • Adapts to any Mocap protocol
  • Optimization of marker locations and anthropometrics.
  • Support Marker based (C3D) and inertial based (BVH) input.
  • Support for standard forceplates: (Types 1-4) plus more.
  • Prediction of ground reaction forces
  • Easy setup with multiple trials and subjects

Overdeterminate kinematic analysis

Musculoskeletal models that use Motion caputure data are different from other types of models found the AMMR. Most importantly, MOCAP models usually require an over-determinate kinematic solver to handle the excess in information that the optical markers provide.

The over-determinate solver in AMS works great, but it can only find velocities and accelerations numerically. That has some performance issue when running inverse dynamics analysis. To overcome the problem, the MOCAP analysis is split into a two-step producedure, as illustrated on the figure below:

../_images/anymocap_flow.png

The overdeterminate kinematic analysis solves the model for positions, and writes joint angles to a a set of files. These joint angles can then be used with the determinate kinematic solver in the inverse dynamic analysis.

See also

The AnyBody tutorials, and the lesson on using the AnyMoCap model