Tabletop Scanning Electron Microscope
From the TV series ARROW
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Project Breakdown
By Richard Molnar
I'd created the design of this prop by incorporating visual cues from two actual tabletop SEMs made by Hitachi and Nikon.
I'd created the design of this prop by incorporating visual cues from two actual tabletop SEMs made by Hitachi and Nikon.
Hitachi TM3000
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JEOL (Nikon) JCM-6000 NeoScope Benchtop SEM
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Approval Process
Two different housings were submitted for consideration (see below). The one selected was my favourite. It was kind of a mash-up between the color and design cues of the Nikon SEM, with the general proportions and layout of the Hitachi version. Both were commercially available custom computer enclosures.
Two different housings were submitted for consideration (see below). The one selected was my favourite. It was kind of a mash-up between the color and design cues of the Nikon SEM, with the general proportions and layout of the Hitachi version. Both were commercially available custom computer enclosures.
Before being approved however, a number of crude mockups were thrown together and photographed for Production approval. The version finally selected, was the least elaborate of those submitted.
This was the most elaborate configuration submitted.
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An alternate housing choice for the SEM.
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The chosen configuration.
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Control panel design rendering.
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In all, there were 9 different versions submitted for Production approval (click photos to enlarge). All included an LCD monitor, keyboard, and mouse that were ultimately supplied by Production; different from those used in the mockups.
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Construction
Once the chosen case was selected, I needed to relocate the drive bays from the top, to their new location at the bottom, in order to accommodate the planned location of the specimen chamber drawer. This was achieved by first drilling out the rivets that held the front chassis together, inverting it, then re-riveting it back together (I also removed a hard drive cage that was going to be problematic). It was then a simple matter to snap the case fascia back on… now inverted 180 degrees. |
The stock configuration of the case.
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Graphical Treatments Prior to modifying the computer case, I'd dropped off a 1:1 rendering of the control panel and some decal designs to a favorite sign shop of mine for several different modes of output. They produced 2 control panel cosmetic pieces made from a novel clear/colored layered plastic sheet as well as some custom decals. "Reverse-Engraving" The type of plastic sheet I'd selected for engraving was about 1/16" thick and featured a satin grey finish. That said, this material is actually 2 different thinner sheets laminated together; the top being the color-layer, and the bottom being clear. When "reverse engraved" onto the clear-layer, the text appears mirrored. This is intentional because this type of material is designed to be viewed from the color-layer side where it appears normal. As you might expect, the text is rendered as clear lettering on a grey background. This provides 2 useful options for finishing: (1) Backfilling the engraved lettering with paint in the color of your choice (making it appear custom printed) or (2), leave it transparent for backlighting. I during this project I used both options. The finished control panel that looks as though it had been reverse silk-screened on polycarbonate sheet and is indistinguishable from a commercially made product. Two oval shaped indicators and two different "Resolution Scale" graphics were left clear and received the appropriate LED backlighting for their respective functions. Custom Decals
When detailing props of this kind I aways make an effort to include some authentic looking and interesting graphical treatments. In the case of one of the decals I'd designed, I requested that Production "clear" a manufacture's name that I could incorporate into the front panel and nameplate. To my delight, they provided "Rabehl Scientific"; named after Ken Rabehl, the show's Art Director, friend, and long-term colleague of mine. (It's actually common practice to use crew member names for this purpose.) |
Control panel reverse-engraving Instructions to the sign shop.
The completed upper control panel depicting both reverse-engraved text finishing options: some areas backfilled with paint, while others receive LED backlight illumination.
Custom Manufacturer's Nameplate
Custom Warning Decal
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Enhancements
Although I made an effort to stay true to the functional attributes of real tabletop SEMs, one feature everyone wanted to see was a motorized specimen chamber door. It was simply deemed more interesting than the manually operated version found on the genuine article. To this end, Prop Master, Ken Hawryliw suggested that I consider using the tray mechanism from a CD/DVD drive in order to achieve this effect economically. Unfortunately, this kind of mechanism is only suited to transporting a light-weight payload and was quickly abandoned in favor of a purpose-built mechanism. Other concessions made to enhance the appearance were the inclusion of LED lighting inside the specimen chamber and a "blue-halo" effect that radiates from the aluminum "X/Y" control dials. |
The tabletop SEM on set.
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Dialing It In
Another "enhancement' suggested by the design, was the purported ability to position the specimen stage via electric motors controlled by the X/Y dials. This concept was really born out of necessity. Real SEMs actually had elaborate and precise mechanical linkages connected to the X/Y dials that were fully visible whenever the specimen chamber door was open. Given time and budget constraints, I opted for suggesting that this particular SEM had an advanced "position-by-wire" feature, which justified the simplified design of the positioning mechanism.
Another "enhancement' suggested by the design, was the purported ability to position the specimen stage via electric motors controlled by the X/Y dials. This concept was really born out of necessity. Real SEMs actually had elaborate and precise mechanical linkages connected to the X/Y dials that were fully visible whenever the specimen chamber door was open. Given time and budget constraints, I opted for suggesting that this particular SEM had an advanced "position-by-wire" feature, which justified the simplified design of the positioning mechanism.
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Fine Adjustments
Another imagined "advanced feature" was the "COURSE and "FINE" X/Y adjustment. This novel feature was simulated by pressed the face of either positioning dial, which caused backlit indicators to toggle between large and small scales. This feature was relatively easy to achieve, given that the dials were actually a ready-made computer accessory that already incorporated an internal momentary switch (as well as the aforementioned "blue-halo" illumination). |
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Choosing this particular item to serve as the X/Y dials was inspired by something I noticed in one of the SEM reference photos I'd gathered. It immediately caught my eye, as it was something I used everyday… an accessory connected to my iMac called a "Powermate" (below left).
The highlighted item is a GRIFFIN TECHNOLOGY "Powermate".
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EUREKA! I now had a viable candidate for the requisite turned aluminum dials, with the added bonus, of a nifty lighting-effect, and a useful momentary pushbutton.
Electronics Design
The electronics were a pretty straight forward amalgamation of off-the-shelf electronic modules for servomotor and LED indicator control. I'd chosen this route, as it was faster and more efficient (and less expensive to the client) to utilize on-hand solutions, rather than designing and building a custom control board.
The electronics were a pretty straight forward amalgamation of off-the-shelf electronic modules for servomotor and LED indicator control. I'd chosen this route, as it was faster and more efficient (and less expensive to the client) to utilize on-hand solutions, rather than designing and building a custom control board.
Control Electronics Schematic
Internal Layout
Sometimes having a "good eye" and a little luck helps. The components that became the basis of the servo drawer assembly and specimen chamber base were made from 2 different sizes of commercially available electronic enclosures made from aluminum.
Besides being the appropriate size, they already had useful channels incorporated into their interior walls that were designed to accommodate the insertion of appropriately sized circuit boards. I was able to use a pair of these channels as guideways for the movable drawer.
The drawer component was made from 1/16" aluminum sheet stock, which would move smoothly through these channels. The application of self-adhesive TEFLON tape to the edges of the drawer that engaged the channels further enhanced the smoothness of travel and tightened up the tolerance to provide a more precise fit.
Sometimes having a "good eye" and a little luck helps. The components that became the basis of the servo drawer assembly and specimen chamber base were made from 2 different sizes of commercially available electronic enclosures made from aluminum.
Besides being the appropriate size, they already had useful channels incorporated into their interior walls that were designed to accommodate the insertion of appropriately sized circuit boards. I was able to use a pair of these channels as guideways for the movable drawer.
The drawer component was made from 1/16" aluminum sheet stock, which would move smoothly through these channels. The application of self-adhesive TEFLON tape to the edges of the drawer that engaged the channels further enhanced the smoothness of travel and tightened up the tolerance to provide a more precise fit.
Internal Layout
Video Clip Showing Operational Features
Tabletop SEM - ARROW from PROPOLOGY on Vimeo.
As Seen on ARROW
The RABELL SCIENTIFIC TT-1B tabletop SEM as seen in the episode "The Scientist"
Surprisingly little custom fabrication was required to complete this project. That said, a great deal of planning went into ordering the right components and ensuring that they would arrive on time in order to to meet the completion deadline. Really fun to design and build!