An articulated 3D human in HTML5

I am developing an open sign language gesture builder, in some ways very similar to Vcom3D's Gesture Builder - see product demo on bottom of this page.

The main goal is to make this app work in all major browsers without any need to install a plugin or browser add-ons.

I am having problems finding the simplest way to create an articulated human character, that would have controllable arms and fingers, just as the avatar from Vcom3D's Gesture Builder:

I googled alot and checked many 3D human model creators/manipulators, like MakeHuman and Blender, which could be helpful developing a 3D model, but i have no idea how I could use it inside an HTML5 environment.

Do you have any ideas? I would be very thankful!

Edit: Chico3001 gave a really good answer explaining how to implement animation using Javascript and HTML5 elements. However, my real problem is how to create relatively good looking sprites that I could use to create such animations?

I like the comment: "You mean, you want to build a spaceship, but don't know how to build a bike?"

I do not think the sprites will help you very far. Your example screenshot indicates you want to rotate objects and also you want to give it a notion of 3D, which involves shading and other nice extras.

If somebody would buy me time (lots of time) and I had the task to build a 3D gesture builder, I would base all my work on things like that:

http://de.wikipedia.org/wiki/Scalable_Vector_Graphics

http://www.lutanho.net/svgvml3d/

http://www.svgopen.org/2010/papers/58-WebGL__SVG/

http://javascript.open-libraries.com/multimedia/3d/svg-vml-3d-javscript-libraries/

http://debeissat.nicolas.free.fr/svg3d.php