The joints are a mixture of ball joints, pivots and hinges. Most of the joints have pistons as their driving force, but some are missing otherwise the image becomes a little crowded.
Each hand currently has nineteen pistons on it. The hands are very important as they are they primary way that the robots; which are mute, can express themselves.
The retro power packs / generators on the back, and the aerial on the front will both have 'Metropolis' like overlapping rings of energy constantly moving up and down them.