November 1998
Mike Plissi and Calum Torrie came to Hannover for a final design review of
the modecleaner double pendulums. For the first time three complete stacks
have been assembled, including motors and flex-pivots. The top-plates have
been manufactured by Skodock; they were damped by partly filling them with
graphite-doped RTV. A dummy mirror served to test the suspension. The result
of this dry exercise was that the mechanical design is ok, up to a few little
changes to be made by our workshop.
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| Angela Di Virgilio from Pisa came by to visit GEO 600. Here she takes a look at the assembly shop. (From l.t.r.: Karsten, Angela, Aniello, Benno, Mike.) | ||
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| Benno and Kasem look how to fix the roundtables to the TCMa top plate
lying on it's back. The top "plate" has evolved from a planar to a rather Escher-like structure. | Peter and Jochen look at the top plate hovering above the stacks. | |
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| Kasem and Benno put the top plate onto the stacks. | Mike adjusts the fit of the top plate. | |
Stacks and Top Plate
After being equipped with all the intermediate masses and mirrors the top plates have to be inserted into the tank and placed onto the stacks. This sequence shows the device for the soft lowering of the top plates. The test run proved the feasibility of this concept.
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| This view shows the stacks mounted on the resp. holder plates. The
large thick thread-poles hold the upper part of the tank after opening it. The small ones bear square plates for the lowering device. | The lowering device consists of three beams and a round plate. The beams are fixed to the square plates. | |
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| Here the top plate is bolted to the lowering device. The stage is
lowered by turning the nuts holding the square plates. (From l.t.r.: Mike, Benno, Calum, Peter.) | The top plate sits upon the stacks. Now the lowering device can be removed. |
Assembly of the Double Pendulum
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| The top plates are made from box-section stainless steel elements. There are nozzles in each layer in order to allow damping material to be filled in. Here Mike and Calum apply fluid graphite-doped RTV to the top plates. A rather messy affair! | By contrast the wiring of the control devices is a very delicate affair. The top plate has been inserted into the tank. From the intermediate round table the coil holder goes down. Below one can see a dummy mirror. Calum and Benno fix the wires of the coils. |
Stacks, Top Plate and Pendulum
These pictures show various stages of a test run trying the assembly of the
modecleaner suspension. After being equipped with an intermediate mass, coils
and a dummy mirror, the top plate is lowered onto the stacks.
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