Last year, the 3D printing industry was stirred by a new proofofconcept put forth by Autodesk known as Project Escher. With an exciting video demonstrating how the technology worked, Autodesk unveiled a method for simultaneously 3D printing different parts of an object with multiple printheads.
The Cronus 3D printer from Titan Robotics running Autodesk Netfabb. (Image courtesy of Titan Robotics.)
As exciting as the footage was, the industry has since been waiting for signs that Project Escher would actually be available to the public. At CES this year, the wait was put to an end as Colorado-based start-up Titan Robotics showed off Cronus, the first commercially available 3D printer relying on Project Escher technology.
ENGINEERING.com spoke with the CEO of Titan Robotics, Clay Guillory, about Cronus and what it means for 3D printing.
The technology behind Project Escher can be implemented into 3D printers using a new plug-in for Netfabb, Autodesk's 3D printing software. With a free version of Netfabb, it's possible to run two printheads, but, as users upgrade, it becomes possible to control even more tool heads to simultaneously work on different parts of the same project. Imagine five individual, independent bots printing one very long part on a single printbed. That's what Cronus does.
Using Netfabb, the Cronus is able to print with five independent printheads simultaneously. (Image courtesy of Titan Robotics.)
The way that Netfabb is able to manage multiple bots at once is through a single computer referred to as the “conductor.” Outputting a toolpath with built-in checkpoints for the printheads, the conductor instructs each player in the fabrication orchestra where and when to print. Each printhead is aware of its position and relays that information to the conductor, building what Autodesk calls “collaborative control.” In the case of Cronus, this computer is a Raspberry Pi mounted to the printer.
“Previously, if you were to do something like this on a dual-channel CNC or a three- or four multichannel CNC, you’d have to use sensors,” Guillory explained. “The software eliminates the need to have a million dollars’ worth of sensors on a machine like this.”
Titan Robotics is already known for its big 3D printers, but in order to produce big parts quickly, the firm relies on a heavy duty pellet extruder with a wide nozzle for high output extrusion of 10 pounds per hour. This, however, leads to very large layer lines that require further CNC machining for a decent finish. With Cronus and collaborative control, however, it's possible to 3D print large-scale parts with fine detail at high speeds.
The ability to deploy five printheads to work on one big print allows Cronus to 3D print with 3D printing filament and fine nozzles. Therefore, the printer has high resolution, but can print with the same speed as a pellet extruder, traveling at a rate of over one meter per second. And it does so in a sizable build volume of 72 in x 30 in x 20 in.
Cronus uses five gantries to 3D print objects at 4 to 5 times the speed of traditional thermoplastic extrusion systems. (Image courtesy of Titan Robotics.)
There already exist on the market 3D printers that use multiple printheads to fabricate parts, such as the Stacker S4 3D printer, and, though these machines can print duplicate objects at once, the printheads work in unison.
Guillory said, “The Cronus and Autodesk Netfabb's collaborative multi-head 3D printing technology is very different from Stacker 3D and printers like it, as those machines can only print several of the same part in unison on a single bed using a single gantry. You are limited to size and can only print the same model at a time. The Cronus, utilizing Netfabb, could do something similar but even more advanced, acting as five individual machines printing the same part or even different parts all at the same time. On the Cronus, the multiple printheads move independently of each other; they're not bound to the same toolpathing like on Stacker 3D. But like we talked about, the real beauty of the Cronus is the software that can direct all five printheads to work together on a single large part—each of the five printheads have an optimized tool path to fabricate a part in the most efficient way possible.”
Autodesk first turned to Titan Robotics for its experience developing custom machines. “Cronus is the first industrial version of Project Escher using that technology,” Guillory said. “They had built machines on their own, but they were kind of like RepRaps, and they weren't very heavy duty. So, they contacted us and we built an industrial solution for testing out their software.”
Interestingly, Titan Robotics got into the business of custom industrial 3D printers through Guillory’s previous experience as a mechanical engineer for a custom CNC manufacturer in Colorado called Diversified Machine Systems (DMS).
Guillory relayed the story, “I was one of two mechanical engineers that designed all of their machines, and they make custom CNC routers. So, every day I'd have a new CNC to build. It was always a puzzle, and I did that for two years. Then, one day, I built a Prusa i3 RepRap [3D printer kit] in my living room as a hobby. I put an ad on craigslist right after I got it printing. I thought I'd be building RepRaps for people, but, the next day, someone called me and said they wanted a 30 in x 30 in x 45 in machine.”
Guillory then built half of the machine in his garage and the other half at DMS. Soon after, Guillory started seeing interest from other parties and decided to quit his job at DMS to pursue custom 3D printer manufacturing fulltime. For a year and a half, he worked out of his garage until finally getting an 8,000-square foot workshop space and now has 15 employees.
Unlike some of the other larger 3D printers on the market, which often feature aluminum frames and stepper motors, Titan Robotics' machines are all made from steel, milled and calibrated inhouse. The firm's equipment also uses recirculating ball screws to provide virtually no backlash and closed loop AC servo motors, which are both fast and precise.
That first printer made for Guillory's craigslist customer went on to become the company's flagship printer, Atlas. Titan Robotics has also put out the slightly smaller, but still substantial, Hyperion 3D printer, which has a 24 in x 24 in x 24 in build volume. All of the firm's machines are fully customizable.
The Future of Collaborative Cronus
Guillory has said that, so far, Titan Robotics has received a good deal of serious interest in the new printer and envisions Cronus being used for very fast prototype iteration and even the production of end parts.
For instance, Guillory explained that his mechanical engineer, medal-winning paralympic athlete Allison Jones, wants to see the machine used to quickly manufacture custom prosthetics. Printing a large prosthetic socket might take two days on Atlas, but might only take two hours on Cronus, according to Guillory.
Because, in a future release of Netfabb, it's will be possible to prep parts for hybrid manufacturing, for use of both 3D printing extruders and CNC routers, it's not difficult to imagine what a Cronus of the future might look like. While a part is printed on one end of the printbed, perhaps even with a pellet extruder, a CNC router might be shaving it at the other end.
In fact, Guillory said that Titan Robotics is working on a hybrid platform, in addition to a machine named Prometheus, which, as one might guess from the name, will be even larger than the printers made by the company so far. More than that, Prometheus will be engineered to use ULTEM, a plastic with such a high melting temperature and thermal stress that it is impossible to work with on almost any 3D printer not made by Stratasys.
If Cronus can already produce an object in one-fourth to one-fifth the time it takes another extrusion 3D printer to do the same, picture what it might do with hybrid manufacturing capabilities and aerospace-grade plastic. Swap out Cronus’s gantry system for industrial robotic arms, and you’ve got the foundation for an entire assembly line of robots performing fabrication, pick-and-place, assembly and everything else in one production workflow.
In other words, Titan Robotics may be working on some very big things and we'll hopefully be able to update you with more details on them as soon as this spring. Until then, you can visit the company's website
for more details.