A little over a year ago, Rich Ranky was at North­eastern, working on research for his PhD about how to build a force-​​measuring sensor into a plastic com­po­nent. Back then, Ranky was injecting con­duc­tive slurry into plastic pieces with a caulking gun. Now, his 3D printer, Donatello, prints patented sen­sors that mea­sure tem­per­a­ture, vibra­tion, heart sen­sors and elec­tricity, all for a cost between $10 to $15.

Ranky spun his com­pany, 3-​​Spark, out of North­eastern with pro­fes­sors Con­stan­tinos Mavroidis and Mark Sivak. He received $100,000 in seed funding from the Uni­ver­sity, and uses the school’s machine shops for most of his hard­ware development.

I feel like Northeastern’s baby,” Ranky said, laughing. “They have been really, really good to me.”

Though he appre­ci­ates the exer­cise he gets from biking back and forth from North­eastern to Mass­Chal­lenge, Ranky is lob­bying the accel­er­ator to install a machine shop some­where in the building, per­haps in the new loca­tion at the Inno­va­tion Design Center. Until that time, things will con­tinue to be a little chaotic for 3Spark, but not nearly as chaotic as the printer itself.

As Ranky explains the inner-​​workings of the printer:

There is a plastic depo­si­tion system which is the plastic laying down the housing and frame­work of the struc­ture, and then there is the con­duc­tive depo­si­tion system—patent-pending—which is putting the con­duc­tive mate­rial down. How­ever, you design it in the com­puter, the plastic goes through the layers and it will leave a channel half open and then with the motor­ized syringe, it off­sets and squeezes the con­duc­tive mate­rial into the channel and the plastic con­tinues building on top of it.

Basi­cally, the plastic body of the sensor is printed layer-​​by-​​layer, sort of like a reverse shredder. As it builds it leaves a little gap, which is filled with con­duc­tive mate­rial resulting in what looks like a metal splinter.


Read the article at BostInno →