Learning Tai Chi with 3D?

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 I have recently started learning Chen-style Tai Chi. I like the activity and my instructor, but as I am finding out, it requires more than just a few minutes of practice to improve performance. I have started looking for sources for additional help. Recorded videos are very helpful as they can be a tool for practising at home, but the computer nerd in me wonders if there is a better way. 

What I came up with is to create 3D animations in a similar way to a video recording, but with the added benefit that the user could set the point of view of the scene at will. So I started to look around to see how that could be achieved, as my knowledge of the field is second to none. 

I learned that motion capture could be used to obtain the motion pattern from a human performer, and that piece of information could be later used to animate a 3D character in a virtual environment. However, the way this is done sometimes requires expensive equipment that may also interfere with the range of motion of the performer, but when done right, it offers a very natural motion for animated 3D characters. More recently, probably surfing the AI wave, several companies (like Move.ai, Deepmotion, or Rokoko) have popped up in this space with software tools that offer single and multi-camera solutions that allegedly require no other tools than digital cameras.

I have tried the free offering of these companies with some video recordings, but while the demos they show look really good, my experience has been pretty bad, and only 15 or 20 seconds of video were permitted for my tests. To make things worse, I realized that on top of the whole body motion capture, the fingers' motion is also important in Tai Chi, which makes it an even more demanding motion capture project. 

Then I looked around the web for existing Tai Chi motion capture projects. I have found different sources of captures with different technologies, some even including the fingers motion, but turning these into an animated 3D character requires a series of different processing steps I am not familiar with (character skeleton, inverse kinematics to transform the motion capture into angles of joints movements, adapting that to the geometry of the chosen 3D character skeleton aka retargetting). And none of these captures were for Chen-style Tai Chi, nor of full forms (a form is a sequence of choreographed movements or postures).

All in all, it seems a larger project than I anticipated, and for now, I can only show you a quick prototype I made as a proof of concept. Should I find enough traction, I would continue the development. But beyond the technical details, the participation of a knowledgeable Tai Chi master would be required. My guess is that those who make a living teaching Tai Chi may not be interested in creating tools they could perceive as a threat to their job. 

I do not think that learning Tai Chi is very different from other physical activities, like other martial arts or dancing. And for all these activities, I reckon getting beyond the video recording into the 3D animation might be a powerful learning tool that, in my opinion, may help the technology-savvy newcomers.

Tips: You can click on the prototype to change the point of view of the animation. You can use the scroller to change the animation speed. You can click here to get the animation on a new webpage.

Sorry, I used a canned animation for the prototype and not a real Tai Chi set of movements.

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