Accomplishing the Unlikely

Robotic Screwdriver Armature

 This project required the design of a practical screwdriving armature to be fitted to an existing robot arm. The armature had to be lightweight and easily maneuverable to fit through small slats on casings and screw printed circuit boards into place inside as another robot soldered the wires connecting the different PCBs.

As usual, I began by making preliminary drawings. I drew various designs and determined which were the most practical. I designed several variations of the rotary actuator placements to find something which required little energy while not restricting capability and maneuverability. The original design, done by an engineer within the company itself, incorporated various moving parts which generated conflicting residual forces. A great deal of error-prone calculations had to be done to compensate for the resistance and other interference. My design eliminated such conflicts in movement.

The preliminary drawings are shown below. 

 I showed the preliminary designs to the client. He made a formal presentation of them and, with his own client, determined which would be the most practical for their particular application. When they had made the determination and planned the dimensions, my client sent me the results, and I created a new design based on it. I incorporated an infrared laser which detects where the screw must be placed - the distance between the infrared laser and the screwdriver is programmed as a constant, and a motor in the robot arm (not shown) adjusts the arm that precise distance (dimension "D") upon detection of the placement.

 The final fabrication drawings, drawn in AutoCAD, are shown below.