Robo Challenge is a creative engineering company in Birmingham that pushes design and materials to the cutting edge. Brothers Grant and James, and their father Nick, have built a reputation for their robots being among the toughest and most creative in the world.

Robo Challenge combines the latest technologies with engineering design expertise to bring ideas to life. Among other projects, the "House Robots" for the TV series "Robot Wars" were designed here, the world's fastest chainsaw-powered vehicle was built, and an autonomous image recognition and GPS-based line marker for soccer fields was developed. 

Challenge

Spectre had to be created: a next-generation combat robot equipped with a state-of-the-art hydraulic breaker as a weapon. As the engineering team behind BBC's "Robot Wars," Robo Challenge was not allowed to participate in the robot battles here. So, the Spectre was quickly designed for the "King Of Bots" (KOB) tournament in China. James Cooper, Managing Director of Robo Challenge, explains: "In no other industry are materials, batteries, and motors pushed to their limits like in robot combat. We have to construct a 110-kilogram fighting machine that then has three minutes to either destroy its opponent or be destroyed by it in a 110-ton bulletproof arena. 

There's one crucial difference between combat robots and the automotive or aerospace industries: With combat robots, safety doesn't have to be considered. Unlike in Formula 1, for example, there's no safety risk for spectators during robot battles, even in the most spectacular fight scenes. This allows us to push the tolerances of material specifications much further without having to fear catastrophic consequences."

Robo Challenge's design brief for the new combat robot called for a reinvention of the hydraulic breaker. Rotating weapons have dominated robot combat recently, and the redesign was to be inspired by this. James further explains: "King of Bots is our opportunity to combine many creative designs for an extreme environment. We wanted to offer the world the seemingly impossible: a hydraulic breaker that would push the technological envelope of 'Robot Wars'."

Solution

Markforged 3D printer from Mark3D: Robo Challenge needed a reliable, high-strength 3D printer capable of 3D printing ready-to-use parts with a more organic design and stronger materials. The team turned to Mark3D, an award-winning UK reseller of Markforged 3D printers. Mark3D sells, supports, and installs Markforged equipment, which uses CFF (Continuous Filament Fabrication) technology to produce finished products. Robo Challenge invested in a Mark Two 3D printer with dual print heads. One print head extrudes Onyx, while the other reinforces the Onyx with carbon fiber. Carbon fiber is six times stronger and 18 times stiffer than Onyx, and was developed as a replacement for aluminum. Components printed with carbon fiber are as strong as aluminum, with a flexural strength of 470 MPa. 

"Thanks to Markforged's carbon fiber 3D printer from Mark3D, the possibilities are now open to us. We can push the boundaries of materials and tolerances, creating super-strong and featherweight 3D printed components." James Cooper, Managing Director, Robo Challenge

Markforged's 3D printers can also reinforce 3D printed components with Kevlar and fiberglass.

For James, reliability is paramount: "Spectre's success is based on being ready to fight in the arena and being able to take a beating. The carbon fiber is as strong as aluminum. The filaments used in Markforged 3D printers make a print more dimensionally stable than the FDM printers we've used previously. We can orient the carbon fiber as needed, ensuring our part has sufficient stability at any point and in any axis." Markforged's CFF technology also allows Robo Challenge more design freedom. James knows that with 3D printing, his team can invest more time in creating the perfect part: "We no longer worry about how our design will be compromised by steel and conventional manufacturing methods. We're no longer limited to the capabilities of a 3-axis mill; we can experiment with generative design and create any shape imaginable."

Stronger and lighter materials 3D printing Previously, Spectre's "clavicles" were made of aluminum. Each weighed around one kilogram. Using the carbon fiber technology of the Markforged 3D printer, the weight was halved without sacrificing strength. "We utilized the advantages of carbon fiber for all of Spectre's internal components. This allowed us to achieve stiffness and strength without increasing the weight. This was a huge step forward for us," reports James. By 3D printing with carbon fiber, Robo Challenge saved an average of 500 grams per internal component. This reduced Spectre's overall weight by a total of 2.5 kilograms. Robo Challenge used this to install a second battery pack, which allows Spectre's crusher to operate at its full power.

The result

Spectre won the 2017 KOB World Championship. Its advanced hydraulic breaker can now exert 22 tons of force (the last highly successful hydraulic breaker only exerted nine tons). James explains what sets Spectre apart from rival robots: “Meticulous attention to detail and precise analysis of components. Spectre is not just a design project, but also a work of art.” “Thanks to Markforged’s carbon fiber 3D printer from Mark3D, the possibilities are now open to us. We can push the boundaries with materials and their tolerances, creating super-strong and feather-light 3D printed components. The result is a robot optimized in every way, one that looks as good as if it belongs in a Formula 1 garage, not in an arena of fighting robots.” For the 2018 KOB Championship in China, Robo Challenge plans to use Spectre, generative
Design and 3D printed parts to defend the title.

At a glance
– Replace aluminum parts with 3D-printed components
– Super strong end products
– About 50% lighter parts
– No more design compromises

"Mark3D is a great provider of our Markforged 3D printer and associated materials. The dedicated team is incredibly helpful, providing us with datasheets and intricate samples of the many available materials. When projects were under time pressure, they far exceeded our expectations with fast and practical support. To ensure Spectre was ready for battle in time, we even had some of its components printed at Mark3D!" James Cooper, RoboChallenge