3D printers keep managing to blow our collective minds: from a 3D-printed heart to a an entire 3D-printed car, it seems there's almost nothing the machines can't do. Not impressed with any of that? Well, how about the fact that there's now a 3D printer in the space station that can print out the necessary tools to make repairs? It's admittedly all very exciting, even for the most skeptical among us.
Elias Bakken found himself taken with the 3D printing craze, but frustrated with the sheer noise from a 3D printer. So he found a way to fix it. The Replicape is an open source BeagleBone cape meant to make 3D printing a much more pleasant experience.
The Replicape cuts down on 3D printing noise.
As a maker, what was the biggest frustration you had working with 3D printers?
One of the biggest frustrations I had when starting hacking on 3D-printers was the amount of setup needed to get started with changing just a small thing in the firmware. At the time, I was trying to make a robotic arm for serving coffee on my MakerBot Cupcake. The machine broke half way (of course) and the only option for fixing it at the time was to switch from a DC motor based extruder to a stepper motor based extruder. I did manage to get it working, but the whole process left me thinking "This is not elegant." I still love getting the most out of small micro controllers, but if you want to be efficient, having a modern resourceful development board like BeagleBone Black is just so much more enjoyable to work with in everyday life.
Most people will never have to hack their 3D-printers code at all, but having a setup that makes fixing bugs a happy experience for those who do, makes future development and support that much more fun for all parties.
We do love hacking. What kind of hardware is in this thing?
Replicape is a cape that stacks on top of a BeagleBone Black, making the setup into a 3D-printer controller. Basically what a 3D-printer does is move in 3 physical directions (X, Y, Z) and feed filament into a hot nozzle. That is what the cape does. It has 5 silent stepper motor controllers (Trinamic TMC2100), three high power MOSFETs for controlling heat, inputs for measuring the temperature with thermistors and some smaller MOSFETs for controlling fans etc. It sounds simple and in many ways it is, but the challenge from an electronics standpoint is to get the EMC noise level down, get the temperature spread out sufficiently, and making the design robust to ruthless engineers!
Sounds great, but it must have been difficult bringing it to market.
The biggest hurdle in bringing the Replicape to market I would have to say has been the logistics related to the manufacture and distribution of the product. Everyone can hack together something that works, but making that into a viable product is what takes time. Hardware is easy if it's prototyping: scaling up production, delivering to the customers and handling discrepancies in that process is the difficult part.
The project is a BeagleBone cape.
So why should electrical engineers be interested in this?
Electrical engineers should be interested in Replicape if they're looking for a modern, well designed controller board for their 3D-printer or CNC project. It's not the only one out there, but there is a team behind it whose job it is to answer questions and is pushing the project ahead. That in combination with the fact that it is an open source project with a very liberal license makes it a product worth incorporating in a 3D-printer.
Why did you decide to make it open source?
Both the hardware and software is open source because I have seen the limitations of closed source systems. As an end user, the advantages might not be as obvious, but for any company looking to make either the hardware or software a part of their product, reaching a closed source binary blob will kill many projects in its tracks. I think it's also worth mentioning that open source does not mean that the code is available in a repository: it means having a license which supports further development, and ideally having the history available, well-documented and made available before the product is done.
Your original design won the Texas Instruments cape contest. Was that the motivation behind the Replicape?
Winning the Texas Instruments Cape contest was great back in the day, yes! The $1000 prize was quickly spent on women and booze, but the real prize was having the first batch of Replicapes manufactured, enabling a wider adoption by early adaptors and paving the way for the current revision!
You’re using Elmatica for your PCB curators. Did you have to go through other curators and what advice would you give for those looking to bring their PCB to production?
Elmatica has been an amazing resource through the whole process of developing the new Replicape. Even though this is just a pro bono project for them, because they love the work we are doing and the mindset surrounding this open source project, they have provided the absolute best service and enabled the before mentioned oh-so-difficult scaling-up part to be a lot less painful! Previously we have not used a curator in the same way. This project is really a walk in the park for these guys, who are usually concerned with military grade, dozen layer PCBs with way smaller margins, but it's been great to have an extra set of eyes when moving to a 4 layer PCB. For first timers, it is definitely worth consulting the pros before starting production.
Good advice. One more thing: how in the world do you maintain your majestic Norwegian beards?
Well, I cannot speak for the rest of the team, but personally I use barber Mike from Persons of Interest on Havemeyer in Williamsburg. He keeps my facial threads in line with military precision.
Elias mesmerizes us with his tremendous facial hair.
What would we do without the Norwegians? Well, in this instance, we'd have an insufferably loud 3D printer. Thanks to Elias for his great invention and his helpful beard advice.