Very interesting, I do prefer mechanisms that do not rely on gears as they tend to generate less noise and heat while being more resistant to wear. A properly engineered capstan drive should never need replacing or maintenance.
Not sure if it was you without your name but, an Anon mentioned capstan drives are inherently capable of having both drums remotely connected to localize mass. Though this is true, it would require careful engineering to ensure low friction on the strings.
I do not use those so outside of gunpla. I was thinking she would use normal joints. If you have a good reason for her to use double joints though, please share.
We are planning on making her hollow for many reasons. Keeping her wires hidden within is a yet another advantage to her being hollow. As for pipes in her articulation points, do you mean bushings? Brass bushings can be made very thin with good friction properties. I thought we were planning on using normal bearings. Segmenting her design is indeed necessary for her to have proper articulation, glad you are already thinking about how to segment her design.
Ideally her mass would be mostly localized within her feet and hips. Feet to keep her balanced, the knightmare wheels on her ankle wings will help with this. As you mentioned, spreading out her points of contact with the ground is also a benefit of that design. Hips for balancing as an inverted pendulum. Many self balancing machines use this principle. The higher her mass is, the more torque is required for her to fall over. Since we're planning for her to move her upper torso, having the mass in her hips would be high enough for balancing without adding torsional forces to her waist servo.
We're definitely getting a lot of her design figured out. An editable online design document would be good to organize and update her specifications over time. Any idea for a good place to host such?