Artist 3D Prints an Amazing Thermal Reactive LED ‘MOOD Coaster’

Do you remember those mood rings that were extremely popular in the late ’70s and early ’80s? Even today you still see people wearing these uniquely fascinating pieces of jewelry. The mood ring was invented back in 1975 by Josh Reynolds and Maris Ambats, by bonding liquid crystals with quartz stones, creating a thermochromic element. Changes in temperature generally cause the crystals to reflect different wavelengths of light, changing the colors of the stone in the process. While these rings don’t actually tell you your ‘mood,’ they do a substantial job of telling you your body temperature.

One artist, named Noah Hornberger, has been trying to make a living by creating unique, innovative products. This past year, he has launched an Etsy shop in order to sell his 3D printed home decor, much of which is incredibly beautiful. However, when he heard of a contest from MakerBot and FirstBuild, called the Countertop Challenge, he had to jump at the opportunity, with his idea for a one-of-a-kind 3D printed coaster, called the “MOOD Coaster.”

“The idea for the mood coaster came about because it has been so unusually cold for the last few weeks in Michigan,” Hornberger tells 3DPrint.com. “My morning coffee would keep cooling down so fast, and for some reason I thought of a coaster that would indicate the temperature of the cup. At first I was thinking just a normal thermostat, but then I could see the potential for more of a lighting special effect with RGB LEDS and some programming.”

Much like the mood rings of the ’70s, the MOOD Coaster is based on the same general concept: temperature determines the color displayed. Sorting through a box of “Arduino odds and ends,” Hornberger wondered if he would be able to get a reliable temperature reading using some spare thermistors that he had on hand for repairing his 3D printers.

“A thermistor turns out to be an easy thing to set up and before you know it I had a little demo [running],” Hornberger tells us.

He proceeded to set up his MOOD Coaster so that an ice cold frozen bag of peas would turn the lights blue, while a steaming hot cup of joe would turn them red. The programming code he used sets up a signal for controlling the LEDs and then does a quick calculation which turns the numerical temperature reading into  RGB color. The Arudino Pro Mini then takes this RGB color code and sends a signal to the LEDs, telling them which color to display. There is also a button on the side of the coaster to allow for the selection of different color modes.

The non 3D printed items Hornberger used include the following:

• Brain: Arduino Pro Mini 5v 16mhz
• LEDs: NeoPixel Ring, 24 addressable RGB LEDs
• Temperature: Honeywell 10k Thermistor

He recommends 3D printing the four separate pieces of the coaster using a layer height of 0.25 or 0.3mm. The outer shell also must be printed with a little bit of support material. With his project now complete, Hornberger hopes to have a chance at winning the MakerBot and FirstBuild Countertop Challenge. Feel free to vote for him on Thingiverse.

As for Hornberger’s future plans, we should be expecting to see a lot more from him soon.

“Now that I have some experience selling 3D printed items, I am ready to launch bigger ideas like gestural music synthesizers, reactive robots and other gadgets like the MOOD Coaster,” he tells us.

What do you think of this 3D printed MOOD Coaster? Is it something you would like to have placed under your morning coffee mug each morning? Discuss in the 3D Printed MOOD Coaster forum thread on 3DPB.com. Check out the video of the coaster in action below.