Moving Around Space Without Propellant A mechanism as shown in following picture is floating freely in space.

Concentrating on the main components first, which is the long rod in the middle with another 8 smaller rods connected to it, each having some massive sphere at their end attached, which can be turned 360° via some electric motors inside the long rod. Ignore the rest of the mechanism for a moment.
The long rod hovers above a space platform, exactly where the pink line crosses with the red line.
To start simple, we use the electric motors to first accelerate A1,A2,B1 and B2. 
A1 and B2 get accelerated clockwise. B1 and A2 get accelerated counterclockwise.
This should result in the rod swinging/moving similar to a pendulum, from the red line, towards the green line and back to the red line given the right initial acceleration.
(we neglect friction of the bearings)
We start over again and accelerate A1,A2,B1 and B2 as described above, but this time, when the long rod reaches the point where the pink line crosses the green line, which should be when A1,A2,B1 and B2 have turned 180° (about to swing back towards the red line), we go on to accelerate C1,C2,D1 and D2 similarly.
Now C1,C2,D1 and D2 should counter the swing/movement from the green line back to the red line. 
So in theory, neglecting friction, the long rod should remain static, floating above the green line.
Using the rest of the mechanism now, to rotate the long rod around an arbitrary axis, as i imagine it, this device would move around the area of an imagined sphere, with a radius equal to the distance between the red and green line.
So in theory, just by rotating the rod properly, one could move between the points of where the green and blue lines cross the pink line for example.
So basically, we could move this device around the area of a sphere of any radius, limited only by the initial energy we put in and the stress this device could handle without falling apart.
To move the device, no further energy would be required, yet we would neither violate the conservation of momentum, nor the conservation of energy, while the center of mass would remain at the same place for this closed system, at all times.
Sounds too good to be true, so what did i get wrong? Or would this "UFO" actually work?
 A: Your question is very confusing, so I will first attempt to answer the spirit of your question with a cleaner scenario.
It is possible to "move" from one place to another if there is minimal friction. You can do so with yourself, a large box, and a bag full of baseballs. But it isn't as cool as it sounds (that is why I had to put quotes around move).
If you sit at one end of the box with your baseballs, then in your frame everything is at rest.
If you throw a baseball at the back wall then for a bit both you and the box move in the forward direction and the box will not slow down until after the ball hits the other side. After which point everything can come to rest again. But meanwhile you and the box have moved! And there is no propellant because the baseball stays inside the box.
However the baseball moved in the opposite direction. Eventually you run out of baseballs. And the center of energy doesn't move, not ever, not for an instant not even a little bit.
That last result is a general theorem in the absence of gravity or other external forces, the total momentum stays constant and the center of energy moves at a constant velocity. So if you started with everything at rest, the center of energy can't move.
It's called the center of energy theorem.
If you have two people, one at each end, and each with a bag of baseballs, you can shuttle back and forth. If that's what you want. Nothing deep.
So now we can look at your setup.  Originally everything was at rest. So the center of energy was stationary. So it must stay stationary.
Therefore as you activate your motors some energy must go one way for some energy to go the other way. And there is simply no way to end up with the center of energy in a new location. In the case with the box, the box could move one way because the baseballs move the other way.
I see absolutely no reason to think your motion would be like at all like a pendulum, but sure as some parts move one way the other parts can move an opposite way.
Now if there is gravity or other external forces you can move your center.  And you can still do it without propellants (except the unavoidable electromagnetic and gravitational radiation that happen from just moving around, which is like a kind of friction).
Some effects in that line are rather surprising, such as "swimming through spacetime".
