Mounting the arms

After thinking about the possible features, I decided that my R3-B9 should have two servo-driven arms that sit inside the long horizontal slit in body, together with a bar of four white LEDs. The arms should have a blue LED on the front side, and two white LEDs on the inside, so they extend the four white center LEDs when the arms are opened. Here is the assembly of the arms:

The arms are fastened to micro servos which are mounted inside the body on wooden plates.

The provisional installation looks like this:

In the second step, I build the mount for the four white center LEDs. The LEDs are not directly visible, but light through some white plastic (taken from a vinegar bottle).