The 84th Annual Meeting of the American Association of Physical Anthropologists (2015)


Improving gait generation in fossil primates using multigoal evolutionary robotics

WILLIAM I. SELLERS1 and EISHI HIRASAKI2.

1Faculty of Life Sciences, University of Manchester, 2Primate Research Institute, Kyoto University

March 27, 2015 10:45, Grand Ballroom A/B Add to calendar

Forward dynamic simulation techniques are important tools for reconstructing the locomotion of extinct animals. In these approaches a detailed musculoskeletal model is created and movements are generated by calculating the muscle-generated and external forces and solving the equations of motion for an articulated structure with an appropriate mass distribution. Current popular techniques often rely on optimisation goals such as maximising forward speed or minimising the energetic cost of transport as a way of choosing between the large number of possible muscle activation patterns. However whilst these single goal optimisation approaches work well for hypothesis driven investigation, the quality of the predicted kinematics is often disappointing particularly when more sophisticated 3D models are used. Here we demonstrate, using a high-biofidelity quadrupedal model of a chimpanzee and our newly developed markerless 3D motion capture technique, how the inclusion of multiple optimisation goals greatly improves the kinematic realism of forward dynamic simulations, and particularly how this affects the footfall sequences that the simulation chooses. This work supports the idea that gait choice in primates is unlikely to be dictated by a single biomechanical factor but is more likely to be the result of multiple constraints such as performance, economy, skeletal loading, and balance acting together.

This work was funded by BBSRC, JSPS, NERC and the Leverhulme Trust.