Right from our earliest tricorder development discussions, we felt it was our duty to do something special with the removable data disc concept, which we knew would add a level of immersive interaction and realism to our replica tricorder. Initial thoughts of creating plug-in data discs with USB flash drives buried in them were quickly ruled out. Not only are the discs very close together – requiring a push-to-release mechanism to access them – but we felt that a prosaic, and obviously 20th century, USB plug would look clumsily incongruous on a piece of 23rd century tech, especially when compared with the other uncluttered-looking memory cards clearly in use on the Enterprise.
Our first task was to design an ejector mechanism that would work smoothly and reliably, and fit in the limited space the prop has to offer in this area. The eight-disc array is fairly tightly boxed in between the hood, the lower compartment cavity wall and the back of the tricorder. Disc insertion and ejection is further complicated by the fact that the disc diameter is larger than the apparent opening the discs must pass through to be taken in and out of their dock. An array of spring-loaded latching switches attached to thin, crescent-shaped, bendy ‘catcher’s mitts’, which flex to hold and eject the discs, coupled with an upper “glamour bar” that rotates out of the way when a disc is ejected, provided the aesthetic functionality we were after. With all the discs inserted, and while being displayed in a cabinet, the glamour bar springs into position over the top of the array and the tricorder looks perfectly like a pristine version of the first season hero. But for those that want to boldly go beyond display and into the realm of realistic function, pressing any one of the discs ejects it with a satisfyingly premium click. The latching switch at the back of each disc slot tells the tricorder’s software which of the slots have discs in them.
With the ejector’s mechanical design well on the way to completion, we went to work on making the discs a plausibly functional part of the tricorder’s operation. Initially, we considered ways of ‘writing’ even just small amounts of data wirelessly to the discs (using an RFID chip embedded in the disc), but technical issues caused by the proximity of discs to each other, and the metal outer ring, closed down that idea. Given the capability of the tricorder’s internal electronics, and the onboard memory’s ability to cope with the functions we had planned for it, our thinking moved away from the complexity of adding hardware to each disc. To make the discs integral to the tricorder’s operation, for example, using them to activate the tricorder’s various functions, the tricorder has to be able to identify each disc. To simplify the identification process and add another level to the interaction required by the user to operate the tricorder, we chose to only monitor the disc slot furthest to the right. Using this as the activation position ties nicely in with the possibility that, in the hero prop’s original incarnation, this particular disc was the removable one. The right-most slot also allows us to hide the disc identification sensor behind the moiré panel. |
