New model topology and rigging

A project log for Motion Capture system that you can build yourself

An open hardware-software framework based on inertial sensors that anyone can use to build a human motion capture system.

Bruno LaurencichBruno Laurencich 08/24/2018 at 14:020 Comments

Since we’ve focused our communication efforts in an electronic-oriented website, we’ve been omitting an important part of our project: the 3D model and rigging we use to visualize the captures.

At the beginning we used a slightly modified version of a female model that we downloaded from blendswap.

The model was originally created by AlexanderLee and we really liked its shape, but it was not optimized for real time visualization, and the rigging didn’t match our requirements. This meant that Bruno (Chordata’s founder and a 3D animator himself) had to apply some changes on the fly and in a rush. Then, as it usually happens, we kept recycling the model that resulted from those quick changes.

That kept being a limitation until one day François showed up offering his 3D modeling and rigging skills. He did a great job adapting the model to be used in real-time motion capture.

The changes he made are subtle, and almost invisible to those who are not specialized on 3D modeling:

-Retopology: This is the process of rearranging the flow of polygons on a mesh to better respond to certain deformations. Check out the comparison images below: do you note how smooth the formation in the front area of the shoulder is with the new topology?

Old topology

New topology

-New skinning and weight paint: The “weights” are just values inside each vertex that determine the amount of deformation each bone produces. To correctly set these values a process similar to how spray painting is done. It’s a long process that requires continuous adjustments on several areas over and over again…

Thanks François for this great contribution! Even if the captures can be applied to any arbitrary model and rigging, having a good default one for visualization is a great improvement that will allow us to improve Chordata and test it in better conditions.