Step 1: Brackets
The first picture shows a bracket schema used to hold servos together in an arm construction. The material used to build the entire skeleton is aluminium.
Next picture illustrates previously mentioned aluminium brackets already bended and screwed with servos. The box on the bottom of the arm serves as a connection between the arm construction and base. This joint will be later supported with needle bearing. Thus it will got rid of a significant amount of a load that it would otherwise have to deal with.
Step 2: The Base
The base itself is made out of two aluminium circles. One of them has a hole drilled in the middle which enables servo control horn to be attached to the arm construction. The servo itself was glued between plates that were connected with bolds and nuts. Subsequently all cables from servo motors were wired to a board where an 8-link cable was soldered. This cable connects the control box and robotic arm.
Step 3: Control Box
So, what does the control box consist of? The interior of the box includes arduino, potentiometers that directly controls the arm movements. That is one option. The other one is to classically upload the code to arduino. For this purpose an extension cord for usb cable is needed. Next components are breadboard, and several wires for interconnecting the entire hardware part. The final insight look into the box might be seen in the big picture below.
Step 4: Gripper
The last missing part is a gripper. It is one of very few components not built manually but ordered from the internet. The gripper is screwed on the top of the robotic arm using an aluminium rectangle in between.