This is a progress report on the construction of the apparatus for the Fiber-Optic Michelson-Morley Experiment (FOMMX). The first phase is mechanical, to be followed by electrical, data-taking computer, software, communications, laser/optical fiber phases.

This strictly mechanical phase is perhaps 80% complete. The completed assemblies are shown in the photograph and described below. The main assembly that is not yet done is the motor support frame.

FOMMX Mechanical subsystem requirements:
  1. Provide mechanical support for two 5 meter lengths of optical fiber. Each length is called an arm. The two arms are to be set perpendicular to each other in a horizontal plane.
  2. The arms must rotate in a horizontal plane.
  3. The arms must be positioned near the ceiling, rotating, while taking data. They must be positioned at or a few feet above the floor for initial construction and later maintenance. 

The hub has both arms in place. It is temporarily hanging from the top of the stator.

FOMMX components in the picture:
  1. The optical fibers of the arms will be immediately contained in clear plastic trays about an inch wide. The trays will be slid into the clear 4" diameter clear acrylic tubes. Clear tubes are used to enable anyone to see the optical fiber without dismantling the arms.
  2. Each acrylic tube is supported by an aluminum frame made of four 1" x 2" x 6' extrusions manufactured by These acrylic tubes are attached to the aluminum frames by cords.
  3. The two arm frames are attached to the hub, which is 9" square and 30" high and made from 1" x 1" extrusions. The hub holds the arms perpendicular to each other.
  4. Not yet completed is a servo motor assembly that will fit above the hub and that will cause the hub and arms to rotate at more or less 4 RPM in a horizontal plane.
  5. The height of the assembly will be set near the floor or near the ceiling by an electric hoist mounted in the ceiling.
  6. The hoist is out of the picture but two lines hoist are visible in the picture above two pulleys in the top of the assembly. The 1/8" steel cable leaves the hoist, goes down to the pulley unit, across the pulley unit, then up to an "anchor" in the ceiling. The pulley unit is the top of the stator. The top of the stator will connect to the motor unit when the latter is complete and the motor will connect via a shaft to the hub.
This is the first time that all of the assemblies that have been built have been lifted in the intended manner by the hoist. In this picture, the hub is a foot off the floor, although not immediately apparent. It is directly above the brown piece of cardboard. Thus the post title "Lift-Off". (No rocket engines have been fired in this process.)

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