Chimpanzee Model

We have created a new, general purpose quadrupedal chimpanzee model as part of a Natural Environment Research Council project (NERC NE/C520447/1). It is described in Sellers WI, Margetts L, Bates KT, Chamberlain AT (2013) Exploring Diagonal Gait Using a Forward Dynamic Three-Dimensional Chimpanzee Simulation. Folia Primatologia (2013). The starting point for the model was a full-body CT scan of an adult male chimpanzee that died of natural causes with no obvious musculoskeletal defects at a UK zoo. It was CT scanned after a post-mortem examination and there has been some damage to the skeleton due to that. The skeleton and skin surfaces have been extracted from the CT scan and rigged with anatomically and physiologically correct muscles. In the paper, the model was used to generate quadrupedal walking locomotion to investigate why primates use so-called diagonal sequence gaits when most quadrupedal animals use so-called lateral sequence gaits.

Screen shot of quadrupedal chimpanzee model in GaitSym 2013

A number of files are available for download:
  • The raw CT data of the chimpanzee (scan1 (130MB), scan2 (183MB))
  • The complete set of GaitSym chimpanzee files (26MB) including the skin and bone shapes, fully rigged, posable quadrupedal model, and both new and old format model files showing quadrupedal locomotion.

Two sets of models have been provided. (1) the ones used in the paper; (2) the ones using the new GaitSym 2013 compliant muscle model. It is recommended that the new models are used in future work because the old muscle model is deprecated.

Volumetric rendering of the chimpanzee skull directly from the CT using Osirix.