Max Mahoney (Chemistry) and I worked on a mechanical automata project this morning. Our long-term goal is to create laser cut wooden versions of the various mechanical mechanism building blocks in the beautiful book Karakuri: How to Make Mechanical Paper Models that Move by Keisuke Saka. To get a sense of what the design and development considerations might be, we decided to start with a Thingiverse search, and found Simple Machines – Geneva Stop (CC BY-NC-SA) by Zombie Cat. A few minor adjustments to the layout, and we cut the parts out of 1/4″(ish) hobby plywood. We ended up having to tweak a few of the parts to fit the dowels we had on hand, and we made a few slight modifications to the design based on the differences between the vector files and the thickness of our plywood, but overall it’s a great design and turned out pretty well for our first automata.

Geneva Drive

The rest of the afternoon was spent working with Nicole (student and Innovation Center staffer) on a stencil for organic chemistry.  Max hung around finishing the automata, and answered a few technical questions as Nicole and I worked through the layout in Illustrator.  We tested the first prototype, and decided that the various cut-outs representing the bonds needed to be scaled up a bit.  Below is version 2, including Nicole’s beloved chicken in the lower left hand corner, and a fancy star on the right.

Ochem Stencil

Test stenciling…

Nicole Testing the Stencil

The design finished and tested, we cut the final version out of acrylic.  Success!

Final Version Leaves the Laser

The file is up on Thingiverse, or you can just grab the PDF if you’d like to cut your own.

Kathleen Kirklin (FLC’s Interim President) took the robot for a spin in the library other day.

Kathleen Kirklin Drives Robot

I also had the chance to share with Kathleen and Gary Hartely (Dean) progress on the aquaponics project. The plan is to have the screen display some rolling information about the biological and chemical processes in play, interspersed with footage from the live fishcam that will be inside the tank. Pressing the big green arcade button will bring up charts and graphs of the in-tank (temp, pH, electroconductivity) and out-of-tank (temp, humidity, and perhaps one or two others) sensor data.

Robot Observation

Lots to do, but within the next couple of weeks there should be some serious development work on all parts of the project…

Photos courtesy of Tony Humphreys.

Fantastic progress this week on the aquaponics project.  The Theater Arts department finished the display, and FLC Maintenance drilled the holes in the raised floor under the unit, pulled the power and Ethernet, and bolted the whole thing to the floor to make it topple-proof.  FLC’s Data Science club, spearheaded by Nathaniel Adams (student) and Rebekah Keeley (student) have taken responsibility for the technical implementation, including visual and interaction design, front- and back-end Web development, database work, and getting the Raspberry Pi configured and working with the Arduino, which is doing the data gathering.

Meanwhile Taylor Zenobia (student) and Katie Stackhouse (student) have taken charge of the biological systems, selecting the fish species, and arranging the in-tank decor.

Adding Water

They washed and added the sand, rocks, and plants, then carried the water quite a distance from the Innovation Center to the Library. We’ve got inoculated filter media from the Science Fish (they’re currently living in the IC), which should speed up the tank start-up process. Taylor has been regularly monitoring the water, and once the water chemistry is stable, we’ll look at adding the fish, a few at a time.

Finally got a chance to put the cyanotype UV boxes we worked on over the last couple of weeks into production! Max Mahoney (Chemistry), Christa Oberth (Chemistry), and Heike Schmid (Art) organized a Science Center activity working with students to produce cyanotypes.  Following Max’s explanation of the process and the chemistry involved, and Heike’s discussion of the art history side of the equation, everyone got to work, some preparing paper by painting it with the sensitizer solution, others drying the still wet paper with a hairdryer, and others arranging materials and printing negatives.

Some students used feathers, leaves, and other object to create beautiful photograms, seen here through the UV filtering viewing panels Max and I built into the boxes…


…while others printed negatives on transparency film and used those to expose the photosensitive solution-treated paper.

Tree Photo

A lot of folks showed up, so some used the exposure boxes, and others used good old fashioned sunlight to expose their prints.

Letting the Sun Do the Work

About 16 minutes in the boxes, or longer in the sun, and the prints were ready for a rinse, and some optional post-processing in a bath of hydrogen peroxide (which was supposed to enhance the prints, though students were divided on whether it really did much at all), or tea or coffee (for a sepia look).


I took the opportunity to reproduce a group photo from yesterday’s CCC Maker Advisory Committee.

CCC Maker Advisory

Lots of ideas about how to improve the boxes – bigger, more LEDs, etc. – but very pleased with the version 1 results, and really pleased also to see faculty working on interdisciplinary projects!

After a rather lengthy pause in the project, owing mostly to institutional rhythms, Cameron Hoyt (formerly a student, now an employee of the college in the Theater Arts Department) and his crew began work on the structural skeleton of the aquaponics display.

Aquaponics Project

Sean Fannon (Psychology) and I secured a small grant to get our hands on an OpenBCI, which is an open source brain-computer interface, complete with a headset that can be printed on a 3D printer.  Sean plans to use the device to enable students to do some fairly sophisticated brain research.  Fortunately, the new Ultimaker 2+ Extended has a sufficiently large build envelope, so I set it up to print half of the headset overnight, and watched it on YouTube in an obsessive way using the Open Broadcaster setup.

Printing OpenBCI Mark III

Came in this morning, and it all seems to have printed well. In what is a first, I think I might not have enough PLA on the spool to finish the job.  Unfortunately, the Ultimaker uses the fat stuff (2.85 mm), and the Printrbot uses 1.75 mm, which I’ve got a lot of. I read somewhere that the Ultimaker can be tweaked to run the smaller filament, so I might just have to give that a shot.  Some of the smaller bits I plan to use to test the Form 2 that should arrive some time in early July.

OpenBCI Ultracortex Mark III

Max Mahoney (Chemistry) and I met today to do some preliminary sensor calibration for the aquaponics system.  Max brought over various solutions of known pH and µS/cm.

Solutions of known pH for aquaponics sensor calibration

We connected the pH sensor to the Cooking Hacks Open Aquarium shield, and went through the procedure of calibrating the sensor, which involved basically sticking the sensor into a beaker of various solutions, recording the values, and tweaking some variables in the Arduino sketch.

pH calibration for aquaponics sensor

The process for the electroconductivity sensor was much the same. Both worked without a hitch, and once the calibration procedure was complete, we tested the water from the experimental system – 7.54 ph/298.24 µS/cm – and from the quarantine tank – 7.07 pH/176.83 µS/cm. There’s something up with the temperature sensor, which gives a zero value no matter what, so we’ll need to get that sorted, but overall a very successful work day. To top it of, the power and Ethernet should be installed out in the library tomorrow!

Max calibrating pH sensor for the aquaponics build

The gear is beginning to roll in! As with any reasonably complex endeavor at any reasonably complex institution, procuring the “stuff” to make a project work takes a great deal of time and energy – lots of rules and forms and budget strings and signatures and hoops to be jumped through. For this particular project, the electronics – chiefly Arduino shields and associated sensors – are sourced from a Spanish company called Cooking Hacks.  We chose this particular system because a) the parts seem to be well integrated and seemingly well thought out, and b) Cooking Hacks seems to have the code worked out, not just for the shields and sensor interfaces, but for the server-side bits that make the web integration work.  In short, the goal is to get a prototype up and working with a minimum of coding and fuss, and the Cooking Hacks gear seems to fit the bill.

Making Across the Curriculum - Aquaponics Project Hardware

I was able to get most of the sensors working in relatively short order, so I’m feeling good about the progress.  Still waiting on the purchase order for the tank itself, and the ECO-Cycle Aquaponics Kit for the top, but we were able to get a small test tank up and running, thanks to some spare parts the Biology Department was able to scrounge, and some help from Max Mahoney (Chemistry).

Making Across the Curriculum - Aquaponics Project Test Tank

In addition to the little aquaponics setup above, we gathered up another unused 23-gallon tank, complete with filtration and gravel and all the parts necessary to bring up a complete “development instance” of the project in the Innovation Center, which we’ll use to test the electronics, and to get the water and filtration and fish and procedures sorted out.  Progress!

The Aquaponics Project is taking shape. Met today with Professor Ian Wallace and students from the Theater Arts program to talk about the requirements for installation.

Aquaponics Project Design Meeting

The tentative plan has TA students welding the base, and then skinning it with wood, resplendent with infographics carved using their ShopBot setup. Amy Brinkley (Librarian) moved some furniture this morning to make room for the installation, so we all went out and talked through the project in its natural habitat, kicking around ideas about lighting, associated displays of library materials, and design elements.  Students Cameron and Carlos will be working on some conceptual drawings and models so we can move forward in January!

Max Mahoney (Professor of Chemistry) had an idea about using the Innovation Center’s 3D printer to create some manipulatives to help demonstrate to chemistry students concepts of atomic bonding.  Something like this:

Here’s what Max has to say about it:

The nature of chemical bonds is rooted in complex physical forces. These forces result in atoms being both attracted and held apart at a specific distance. We hope to develop a hands-on model for students, which conveys this important chemical information. Currently available designs of molecular model kits allow the construction of complex molecules in 3 dimensions, but do a poor job of representing the exact nature of each chemical bond. Our goal is to create a model that will allow students to feel the chemical bond and see the bond lengths. The recently discovered ‘inverter magnets’ have the property of both repelling and attracting each other, so that the atoms seem to hold each other in a ‘tractor beam.’ The distance they are separated represents the bond length.

Initial designs will focus on demonstrating the principle of bond length and bond vibration between two atoms. Enclosures for the inverter magnets are currently being 3D printed and their shapes optimized. These models use strong neodymium magnets so that students can feel the significant push and pull of the two ‘atoms.’ Magnets of different strengths will result in varying degrees of bond strengths (and vibrational rates), which can be measured by the student using force gauges.

Subsequent designs of these models will demonstrate each atom’s unique bonding pattern. Specialized cases for the inverter magnets will be 3D printed to mimic an atom’s ability to form multiple bonds.

The key aspect of these models is that the magnets do not touch and can be made to vibrate at a specific frequency so that the model is dynamic. Currently, students are taught these concepts with either static models, or with video animation. The strength of our model lies in the ability for students see and feel tangible objects displaying atomic principles on a macro scale.

We did some design talking/drawing:

Magnet Thought Process 1

Magnet Thought Process 2

Max went home, bought some magnets, taught himself SketchUp, and has printed a few different prototypes.

Magnets - How do they work?

Stay tuned…