Submission Type
Poster
Abstract
By utilizing 3-D computer models, it is possible to use the information to reconstruct the musculature of Tyrannosaurus rex. In this study, we obtained laser scans of a nearly complete set of T. rexforelimb bones from the Field Museum. We imported these scans into the software “Maya” (Autodesk) and articulated the separate bones to form the forelimb and created joints around which the bones can move. Then, we imported this model into another software, “OpenSim” (Stanford), where we created muscles as lines, and made sure they interacted properly by creating “via points” and “wrapping surfaces.” Muscle moment arms were automatically calculated, which roughly correlate with the amount of torque a muscle can produce over a joint. The moment arms for all the muscles around a joint were summed, normalized, and graphed, showing the most efficient angles for bones, which indicates function. Multiple hypotheses were collected to determine feasibility with our dataset. So far, it has been determined that muscles affecting shoulder abduction, flexion, and rotation functioned most efficiently agonistically. Highly positive abduction and flexion and highly negative rotation angles were most efficient. The data were compared with a Guanlong model, a basal tyrannosaur, to determine how moment arms evolved in the clade.
Recommended Citation
Schirrmacher, Kurt, "232-Use of 3-D Models and Muscle Moment Arms to Determine the Function and Evolution of Tyrannosaurus rex Forelimbs" (2024). GREAT Day Posters. 62.
https://knightscholar.geneseo.edu/great-day-symposium/great-day-2024/posters-2024/62
232-Use of 3-D Models and Muscle Moment Arms to Determine the Function and Evolution of Tyrannosaurus rex Forelimbs
By utilizing 3-D computer models, it is possible to use the information to reconstruct the musculature of Tyrannosaurus rex. In this study, we obtained laser scans of a nearly complete set of T. rexforelimb bones from the Field Museum. We imported these scans into the software “Maya” (Autodesk) and articulated the separate bones to form the forelimb and created joints around which the bones can move. Then, we imported this model into another software, “OpenSim” (Stanford), where we created muscles as lines, and made sure they interacted properly by creating “via points” and “wrapping surfaces.” Muscle moment arms were automatically calculated, which roughly correlate with the amount of torque a muscle can produce over a joint. The moment arms for all the muscles around a joint were summed, normalized, and graphed, showing the most efficient angles for bones, which indicates function. Multiple hypotheses were collected to determine feasibility with our dataset. So far, it has been determined that muscles affecting shoulder abduction, flexion, and rotation functioned most efficiently agonistically. Highly positive abduction and flexion and highly negative rotation angles were most efficient. The data were compared with a Guanlong model, a basal tyrannosaur, to determine how moment arms evolved in the clade.