Many projects require electrical or electronic circuitry.  The projects in this section are those with a significant electrical aspect.  Whether logic circuits, display drivers, or mechanical control circuits, these are one-off, hand-wired designs.

Match the Moon!


I designed this interactive for the Planetarium Queue at the Maryland Science Center.  It’s super-simple: there are two large wheels on the front.  The left wheel has images of six planets; the right wheel has images of six moons.  The visitor rotates the left wheel to select a planet and then the right wheel to select the corresponding moon.  When a selection has been made on each wheel, the “Check Answer” button on the control panel illuminates.  Upon pressing the button, the visitor will discover if he is “Correct!” or if he should “Try Again!”.  Even thought this interactive is simple, it garnered high dwell times during prototyping.

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Place the Planet!

I designed this “Place the Planet” interactive for the Planetarium Queue at the Maryland Science Center. The basic idea: to have the visitor line up the planets by increasing distance from the Sun. The positive reaction during prototyping led us to add a similar activity wherein the visitor arranges the planets in order of increasing mass, which we considered (and found to be) slightly more challenging.

Ejection Mechanism

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Project: In Cahners Computer Place, there is 1/3 (cut lengthwise) of an automobile against the wall, around which is a Plexiglas barrier, behind which is a mural of a civic emergency.   Hidden in this car is a faux improvised explosive device (IED).  Within this small corral is a MARCbot.  The MARCbot is a small, wheeled robot with a camera at the end of an articulated boom designed and built specifically to inspect potential IEDs.  It is operated with a remote control unit called an Operator Control Unit (OCU).  This is where I came in.  Even though OCU was designed for combat situations, it was nowhere near robust enough to withstand the museum-going public.  (The preceding sentence is in no way a joke.)  I was asked to design and construct a kiosk that would house the OCU, make it more accessible for people with varying manual dexterity, and to add one final feature, to be explained below. For a sneak preview, see the video below.

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Time Flies!

This is by far the largest single project I have completed for the museum. Graphics aside, nearly every physical aspect of this exhibit was designed and constructed by me. This entry will cover the overall design, cabinetry, control circuitry, mechanical devices, and even the mode of interaction. Due to this entry’s complexity, I will cover Time Flies! in several sub-sections, each accessible by one of the links below.



PER3 Interactive

Fly Cam

Sneak peek for the Fly Cam!

Logic Game

Project: An interactive activity to demonstrate the function of logic gates.  What you see here is a functional prototype. In fact, it has been on the museum floor for years. I designed and built this display simply to demonstrate the possibilities of such an interactive to the powers that be.  Unfortunately, it works exactly as it is and therefore needed no update to be strictly functional.  As a result, this conspicuously raw plywood-and-construction-paper display remains stubbornly in situ.

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Project: Poor vision is frequently caused by the condition wherein one’s retina is no longer located in the lens’s focal plane. This displacement can be either in front of the focal plane (hyperopia), or behind it (myopia). For this project, I wanted to show how the location of the retina could affect the focus of an image and how corrective lenses are used to compensate for these conditions.

Check out this riveting – riveting! – video of the Sliding Retina.

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Project: I designed and constructed a display so that visitors could make simple electrical circuits and observe the way they behave under different configurations.

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Taste Buds!

Project: I designed and constructed an electronic circuit and related display to illustrate the difference between those who are Phenylthiocarbamide (PTC) tasters and those who are not.  Simply put, those who readily taste PTC (a molecule responsible for bitterness) require the activation of only one receptor to experience bitterness, while those who are not PTC tasters require the activation of several receptors.  The program manager of the Human Body Connection decided on the straight-forward approach of having a display with two “taste buds” –  one representing a PTC taster, the other representing a PTC non-taster.  These are the clear plastic domes seen in the photo.  Each taste bud has four receptors in the form of a ring attached to the dome.  The interactive display is activated by a PTC “molecule” carried by the staff.

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