Mock Up Design

 For designing the mock up, we had to change a few of the dimensions due to machining constraints but we were able to keep all the tolerances to the specified values in the drawing package.  The dimension most notably that was changed, was the size of the hex head.  These dimensions changed because of the equipment and the means that were being used to make the hex shape.  All of the other parts were adjusted to reflect this change in hex size. 

 A full solid model and drawing package was made using solid works before we machined our mock up.

Mock Up Fabrication 

Hex Head:
The hex head was made by the University of Idaho Facilities.  It was machined out of tool steel.  The shape was formed by bending three pieces to the appropriate angels and then welding the sides together.

Press Fit Pins:
The pins were made from quarter inch bar stock and the ends were chamfered on the lathe.

Attachment Rails:
These were made from tool steel and milled down to the appropriate size while also getting a nice finish on them.  Then, the hole was milled down through the rods at just under a quarter inch in diameter.  Finally, a threaded hole was added in each rail for the insertion of a set screw to simulate binding.

Fins:
These were made from welding a piece of sheet metal to an eight inch bar stock.  Only the ends were welded to prevent warping and binding of the part.  A holding jig was made to insure that the sheet metal was centered on the rail.

Elements:
These were made out of bar stock of two different sizes.  For the smaller elements, we are going to attach a wire to simulate the wire which is wrapped around each element in the actual assembly.  The shape of the end was done using the CNC lathe.  Then the rods were milled to obtain the slit and hole in them. 

Pin Removal 

Lever Arm System:

 A long lever arm is used to push the pin out using a long moment arm.  Although this design has good mechanical advantage and ease of use with the master slave manipulators, it would have a very complex linkage to prevent interference with the hex head.

 Screw Punch Mechanism:

 This design would require some means of a position system to be moved around the hex head.  The design pictured is a rolling system attached to rails that would be on the table of operation.  A pushing rod would then be screwed down into contact with the pin and then continued to be turned until pin is pushed out the other end.  This design has lots of good attributes including ease of use with master slaves and no real mechanical constraints.  The only downfall is the positioning of the device.

Fin Removal

Gripper Rail System:

This design would use the element contours to grip against and pull the fin out from the hex head, taking the elements with it.  The gripper system makes good use of existing surfaces but with unknown spacing of elements, this design could be hard to implement

Fin Rail Grip System:

This grip system would grip onto the fins and then pull the fin and elements out from the hex head.  Once again, this design makes good use of existing surfaces.  The downfall to this design is the strength of the fin given that it is only .030 inches thick.  It would also require very precise movements with the master slave.

Element Removal

Waffle Maker:

The elements would be rigidly secured on both sides (top holder not shown) to allow for fin to be slide out from under the elements.  This design uses the holes in the fin to secure the fin for ease of pushing or pulling.  The tight positioning of the elements and their weight could make this process difficult. 

Fin/Element Combination:

The combination design both removes the fin and the elements at the same time.  For this design, the elements would have to be strapped together by some means to prevent them for coming with the rail.  This design has many good features along with fast completion of the process and use of existing contours.  The only possible downfalls are the spacing for the hook to attach on the rail and the strength of the materials being pulled on.