The bio-mechanic workspace plugin: Enabling biomechanical measurement and simulation across workflows and software applications

Abstract

The Bio-Mechanic (BM) plugin for the CSIRO Workspace platform is presented and its benefits are discussed in context with the design principles and strengths of Workspace. The BM plugin facilitates a number of activities for biomechanics science including movement measurement, model personalisation, kinematic analysis, forward dynamics simulation, numerical analysis and visualisation pre-processing. Since this codebase is written as a plugin for Workspace it inherits by design a large range of interoperability, reusability and productivity benefits. The structure of the BM plugin is presented in context with typical uses of the operations. File readers have been developed which populate model components from popularly used sources (e.g. common simulation package and marker-based motion capture formats). A range of operations can be used to clean input data, such as to reduce noise in movement or force data. Models can be scaled or rigged to surface meshes. Kinematic analysis can be carried out to determine the characteristics of a body movement or the differences between multiple movements. Forward dynamic simulation can be performed to determine the environmental loading on the body and the internal biomechanical loading such as tendon, muscle and joint forces. Results from kinematic analysis or forward simulation can be graphed using custom widgets and visualised in 3D. Operations and workflows are naturally interoperable, using the same datatypes and interfaces, and easily shareable. When combined with a user interface the workflows can be easily developed into standalone software programs. Four use cases are presented to highlight the benefits of producing biomechanical workflows using the BM Workspace plugin. First, a dataset from the literature is visualised in 3D and the pose of the skeleton and muscles is easily displayed at any of the time instances of the supplied motion data. Second, a simple workflow is presented which uses the same dataset to simulate foot-ground contact during running and to predict the external force on the body and the resulting movement of the body centre of mass. This is a typical high value usage of simulation for biomechanics which is extremely easy to implement and customise for users without a software design background. Third, the use of the plugin to build, analyse, visualise and report on a large and detailed simulation that uses an external solver is described. A coupled biomechanical-smoothed particle hydrodynamics (SPH) simulation is used to study sporting technique improvement where physical experimentation is difficult to perform and quantify. The plugin enables quick model development and analysis which is critical for timely completion of such large simulations. Fourth, a deployed software application built upon the BM plugin is described which combines a database of elite divers and more than sixty diving performances in an interactive virtual experimentation tool for coaches to improve springboard diving technique. Because the software was built in the Workspace environment it is modular, highly interoperable and its design was easily experimented with. As a result, its development was highly agile and productive. Typical with Workspace plugins, the BM plugin has many benefits inherited from the use of the Workspace environment. The operations, workflows and standalone software are highly interactive and intuitive. Operations and workflows are naturally interoperable and reusable. Linkages with other code bases and solvers is easily achieved and already in place for many popular libraries. Productivity of users is increased by the aforementioned benefits which enables more breadth and depth of scientific inquiry to be completed. Finally, commercialisation and speed to market are improved because the method of use is efficient, restructuring can be done easily and quickly and because workflows can be converted into standalone software with little user effort.