I have been working on MEOWSER, my Arduino science fair project since 2008.

What is Mineral Element Browser (MEOWSER)?

Mineral Element Browser (MEOWSER) has two parts. A custom wooden cabinet containing APEX mineral samples with LED lighting has a giant touch screen overlay for navigation. Next to the wooden cabinet is a large touch screen monitor that displays the Periodic Table. You can point at elements on the Periodic Table to illuminate rocks containing that element. Also, you can point at rocks to illuminate elements found in that rock. An Arduino serves as the computer cabinet interface. Arduino software, Computer software, and electronic circuits were built to drive this stuff. An interactive chemistry quiz challenges participants..

MEOWSER ready-to-roll. MEOWSER disassembled.
MEOWSER video demo. MEOWSER APEX Element website.


I took MEOWSER out to visit Maker Faire Orlando 2019. Attendance was crazy crowded and I had a few families tell me they attended just to see MEOWSER for their child prodigies interested in chemistry, etc.
I won first place for Most Interesting and Entertaining Project.
Maker Faire Orlando 2019 MEOWSER First Place.
Darth Vader approved.


My longest running hobby interests have been chemistry and electronics. The old Radio Shack 100-in-1 Electronic Kit and Chemistry sets from the 1960's were my favorite boyhood "toys". There were no integrated circuits or microcontrollers. A single transistor was a big deal. I survived the perils of these toys to graduate from the University of Kansas with degrees in Biochemistry and Petroleum Engineering.
I was introduced to the Maker world by an April 2008 Wired magazine article on the Arduino single-board microcontrollers. My wife somehow knew I was interested and gave me the Arduino Mega [more digital pins and memory] for Christmas. I figured I would play around, learn about these new fancy new microcontrollers, and light up a few LED's.
Then the Maker bug hit. I envisioned a project combining the Arduino with chemistry, software development, and woodworking. MEOWSER was born. I had been viewing all the great online chemistry periodic tables that were showing up. The best one by far is the Dynamic Periodic Table. I was also fascinated with the Wooden Periodic Table which is a physical collection of all the elements and samples of items using those elements. My epiphany was to use a computer mouse to point at the periodic table and create a cabinet full of mineral samples with LED lighting on each sample. The whole thing would have a user interface running on the computer that would talk to an Arduino to control the LED's.

APEX Minerals

In the beginning, MEOWSER was going to be a 100% Element collection. However I quickly realized this was going to be somewhat boring. The vast majority of the elements are gray metals. A cabinet full of these metals didn't seem quite so appealing. Minerals are much more interesting. They come in many colors, shapes, textures, etc. Minerals also are conveniently packaged together into things called rocks which means just one chunk of stuff in my cabinet can represent quite a variety of different elements. Sold. Of course this makes the software and navigation more complicated because MINERALS must now connect ROCKS and ELEMENTS in the navigation.

Once I started identifying the minerals I wanted, I could have just picked the prettiest. But somehow I wanted to be more objective. I wanted some goal on WHAT to collect. That's when I hit upon the idea of
-----An APEX MINERAL contains the highest concentration (by weight) of a particular element. No other mineral contains more of this element.

My APEX definition can be manipulated in the interest of actually having something to display.
  • The mineral must be cheap. I have no desire to collect expensive minerals or go on some extended search for some obscure item.
  • The mineral should be non-weathered rock. There are a large variety of geologic processes which create various minerals. This is ok. What I want to avoid is minerals that have resulted from just general climatic weathering (evaporation, oxidation) since these are by their nature very transient.
  • The mineral should be inorganic. There are a variety of mineral deposits that are organic in origin but I really don't want to count those since these are by their nature very transient.
  • The mineral should NOT be a SALT. These are formed as evaporites or in volcanic fumaroles. They are destroyed on contact with water and make poor permanent collections.
  • The mineral should be a visible clump. There thousands of minerals which could be APEX except for that fact that they really only exist in microscopic quantities.
Most of the rocks were purchased on EBAY and ALIBABA.
My primary resources for researching minerals and APEX worthiness were
I created the MEOWSER APEX Mineral web site to explain each element, the APEX choices I had to make, and what I thought were the coolest information about each element.

MEOWSER Architecture

MEOWSER displays a Periodic Table on the computer. Click on the Periodic Table to send command to an Arduino. Commands are relayed through electronics to drive the LED lights in the cabinet.
I know how to code the computer display and the needed database. That is what paid the bills for my entire career. The database contains tables of data for
  • ELEMENTS - name,description,url,notes
  • MINERALS - name,description,chemical formula,url,notes.
  • ROCKS - name,picture name.
  • CABINETS [each row of rocks is a modular cabinet with it's own electronics] - description, 3 Arduino pins connected.
  • Tables for each many-to-many relationship [yes data modeller IT techy jargon] - MineralElements, RockMinerals, LED's [lights for each rock]

MEOWSER Electronics

I had to experiment with my electronics and the Arduino. My first experiments were to buy some LED lights and turn them on/off using the Arduino. This means learning how to program the Arduino with its language called "Processing". Just another easy programming syntax to learn. My first LED attempts were with low amperage, low lumens, LED's. I soon discovered this was not going to work for display of mineral specimens. So I ordered a few more powerful 100 milliamp LEDS from China. Wait a month. Experiment. Order many of what I need. Wait another month.
The Arduino Mega has 2 limitions I had to overcome. The first limitation is 54 digital pins on Arduino Mega. Each pin drives one LED unless I get tricky. I need to drive 100 LED lights for my mineral cabinet.

My design was to use a BYTE of data sent through an Arduino pin to drive 8 LEDS instead of one. This is possible by splitting the BYTE into 8 BITS. Each BIT drives one LED. A 74hc595 SHIFT REGISTER is an Integrated Circuit chip. It performs this task of splitting a BYTE into BITS. Input one BYTE and Output 8 BITS. I learned how to use the 74hc595 to make this happen. Now it gets even cooler. You can chain 2 74hc595 together so that 2 BYTES from a single Arduino pin can control 16 LED. Since each row of my mineral cabinet has 16 LED (by design), One pin on the Arduino can now control 16 LED. woo hoo. I have now advanced past my childhood old Radio Shack 100-in-1 Electronic Kit and learned about modern Integrated Circuits. A major deal for me.
The second Arduino Mega limitions is that the pins are low power (40 milliamp) and can only drive low power devices. My 100 milliamp LEDS are high power. This means I need a separate power supply for the LEDS. I need to use the Arduino to drive SWITCHES (transistors) to turn on the power for each LED. A standard computer power supply has 10-20 amps of 5 volts. Perfect. I can drive about 100 of my LED safely by simply inserting a Resistor to drop the voltage to the 3.2 volts of the LEDS. I need the Arduino low voltage BIT commands to drive transistors to switch the power on/off to each LED. Another common Integrated Circuit called a ULN2803A Darlington Array is perfect. It is effectively 8 transistors on a chip. So now each mineral cabinet needs 2 74hc595 SHIFT REGISTER and 2 ULN2803A Darlington Array to run 16 LED using just 1 Arduino Data pin. [2 extra pins are needed for each cabinet that I didn't talk about. Arduino Clock pin and Arduino Latch pin]. All electronics are mounted on a breadboard to avoid soldering. Each cabinet has its own breadboard mounted on the back.


My wooden mineral cabinet is version 4.0. Each row of rocks is a separate cabinet with its own breadboard circuitry. These can be separated for maintenance. My first designs were too complicated. My illuminated display labels were not working.
The bottom row is different. It contains the hidden PC power supply and a large area to display a single breadboard for this bottom cabinet that can be illuminated for display purposes.

MEOWSER Photography

MEOWSER displays multiple images for each rock. I had to get photographic closeups for each. Now I can really appreciate the difficulties of lighting for small objects. Many of my photos were taken outdoors for sufficient lighting since I don't have good indoor lighting. The primary image is used to create multiple images hilighting the minerals in each rock.

MEOWSER cabinet Touchframe

I made a MAJOR improvement on MEOWSER a couple years ago. I was able to make the cabinet itself touchable. You point at a rock and the elements in that rock light up. Now MEOWER has smooth 2-way navigation between ROCKS and ELEMENTS. To make this all possible I purchased a Touchframe from China. This is basically what looks like a picture frame which is really an Infrared IR frame intended to make an old computer monitor touch sensitive. Just mount it over MEOWSER (a large outer cabinet had to be built to accomodate the fixed size Touchframes being sold), plug it into the computer, and handle the touch clicks on the cabinet (lots of problems here differentiating between cabinet and computer monitor clicks in the software).

The old MEOWSER navigation used an image of the rock cabinet on the computer screen. This was not intuitive for many users. I never liked the old navigation much.

MEOWSER Conventions

I have taken MEOWSER to several MAKER Fairs. Lots of geeky people showing their stuff. Most attendees see MEOWSER, click a few things, and then quickly move on. However, its fun to watch some kids who get drawn in and will spend 15 minutes poking around and figuring out all the stuff MEOWSER has in it.