Louisiana Tech Region I Status Report


1)  Subcontract Renewal

Kathleen extented the subcontract with Idaho State University (Tony Forest). The contract states that the GEMs should  be delivered to LaTech end of May 2008.

2) Students and Rotator Software ...

We have several students claiming intensive hours working on the software and hardware of the rotator. The truth is that the rotator software has not improved for quite some time .... Remember my JLab talk where I showed the Java GUI  that should be able to steer the rotator ?! Well, The GUI is just a GUI ... nice buttoms, nothing more. Turned out that the two students claiming hours on it (and therefore lots of money) have IMHO not the slightest idea how to talk to the motor controller and how and esp. what to send for i.e. initialization and various motor commands and readbacks.

Consequences: One student actually just quit otherwise we would have fired him anyway. The contract of the other student will expire soon ...

 The motor controller differs quite a lot from i.e. W&M wire scanner. The documentation is poor and is mainly tailored using their commandline interface called TRIPOS which is not useful for a counting house operation during the experiment.
I was about to buy a new motor controller handling 3 motors (rotator + 2 translation stages) that has enough documentation so we can use i.e. LabView and take advantage of the W&M Labview code and modify it. Last week the Italian company of our current motor controller finally responded after several weeks (their standard deadtime) to our emails. They have sent us detailed (it looks detailed ...) information on the internal motor commands and what bit-pattern  have to be sent over the serial bus.
So my goal is to get rid of this good looking but non-functional Java crap and replace it with LabView anyway.

BTW.: TRIPOS is the inhouse (internal) software of the motor controller company. Currently we are using a more or less the original TRIPOS programm for operating the Rotator.

Another (engineering) student is currently working on designing a mechanical system that allows to insert and retract the GEM into/from the rotator ring through
the concrete blocks surrounding the GEMs (collimator housing). He is still fighting with his favorite Solid-Edge CAD program (this is the standard software used by LaTech engineers ...) and he will probably graduate this summer, yeah ...

3) Students and Rotator Hardware

One of the tasks is to measure the mechanical precision of the rotator and translation stages *directly* rather than estimating it from assumed mechanical tolerances i.e. of the worm gear. Since mid December we have a CCD camera system and an optics zoom very similar to the W&M wire scanner. Since end of January I finally could have a meeting with one of these famous Rotator software gurus and get trained on TRIPOS ( ... not on their non-functional JAVA crap). Up to now no student actually made some measurement although they know it is urgent ....

Another hardware related project is to add mechanical end switches on the rotator indicating at least 4 octant position. So instead of rotating ~45 deg from octant to octant you actually rotate the ring until it hits a switch related to the octant you dial in. A survey measurement of the octant cutouts and switches will then be used for microstepping into the perfect position (symmetric coverage of the octant cutout). Task for the students was (and still is ...) on how to add switched to the motor controller (using I/O channels) and how to recognize and process this information in software (starting with TRIPOS).
So I asked to attach i.e. a marker like a dowel pin on the backside of the rotator ring and place a microswitch on its path.
Combined with the CCD camera system you can figure out on how precisely you can come back to an octant position and which element (microswitch position resolution or general mechanical backlash) is the limiting factor.

Another project: making extension cables for the motor controller and translation stages for separating the mircoprocessor based motor controller into a radiation save area:   not completed.
At least the motor controller box is now detached from the aluminum backwall which interfered with the right translation stage before ...





4) Mini Cleanroon Hood

I purchased a small but affordable cleanroom hood that allows to assemble and disassemble current or fure GEMs (i.e. Qweak and/or Fermilab) at LaTech without risking any (additional) contaminations (i.e. lints, flakes, dandruff). When we have time and/or students (...) I would like to refurbish the existing prototype GEMs that are currently in bad shape. The hood has a HEPA filter on top and produces an adjustable overpressure with filtered air (laminar vertical air flow). BTW: This small clean room provides a cleaner environment that the W&M clean room.

   




That's all folks,
    |{laus