I've been wondering how exactly it is that actuators are joined to the structure of a thrust vector control system. The reason I'm confused may be illustrated by the following image of a Vernier engine.
It seems as if the joints upon which the two actuators are fixed allow movement only upon a single axis, and the two actuators are both fixed to the same rigid structure. The Rutherford engine, too, seems to have this structure. The two actuators are fixed $90^\circ$ apart from one another. If one actuator, then, extends to push the engine along its axis, how does the actuator fixed perpendicular to it allow for this motion?
The blue shape in the middle represents the thrust chamber, and the orange rectangles represent the actuators. The green rectangles represent joints with a single degree of freedom, which is the case in the above image so far as I can tell. The problem is that if one actuator were to push the thrust chamber, the other actuator which faces the perpendicular axis would have to twist on an angle to follow the movement of the thrust chamber. I don't see how this is possible if the joints all allow only one degree of freedom.