This project involves two studies:

1) We compared five approaches to model external hand forces and moments (EHF&M) in dynamic two-handed lifting tasks using the Lifting Full-Body model.

2) We improved the Fully Articulated Thoracolumbar Spine model and validated it during 9 dynamic lifting/lowering tasks using the five EHF&M modeling approaches .

License: Spine Musculoskeletal Models

1) For details on the first study (EHF&M modeling approaches), please refer to our paper:
Akhavanfar, M., Uchida, T. K., Clouthier, A. L., & Graham, R. B. (2022). Sharing the Load: Modeling Loads in OpenSim to Simulate Two-Handed Lifting. Multibody System Dynamics, 54(2), 213–234. [DOI: 10.1007/s11044-021-09808-7]

The goal of this study was to compare five modeling approaches for simulating the interaction between external loads and hands. These introduced modeling approaches possess varying complexities and are tested for various two-handed lifting tasks. The accuracy of each approach is assessed by comparing the resulting residual forces and moments. You can download sample model files and data to evaluate the EHF&M approaches from previous releases in the Downloads section.

2) For information about the second study (validating spinal forces estimated by our new model), please refer to our paper:
Akhavanfar, M., Mir-Orefice, A., Uchida, T. K., & Graham, R. B. (2023). An Enhanced Spine Model Validated for Simulating Dynamic Lifting Tasks in OpenSim. Annals of Biomedical Engineering. [DOI: 10.1007/s10439-023-03368-x]

In this study, we developed a new spine model and validated the intervertebral spinal forces estimated by our model during a variety of dynamic lifting/lowering tasks. We also investigated which EHF&M modeling approach resulted in the most accurate spinal load estimates. This new release includes the newly developed spine model for OpenSim, along with sample setup files and MATLAB scripts designed to automatically generate the necessary models and motion files required for kinematic and dynamic analysis of EHF&M Approaches 3–5. Please carefully read the release notes and the README.pdf in the "NewFATLSModelValidation.zip" folder.