Often when we write about robots, we talk about helpful robots, meant to improve our lives or further research in some important way. In this case, however, we’ll be looking at robots built for two simple purposes: to entertain and destroy.
BattleBots is a televised series that first aired in 2000 which brings some of the most robust, most violent robots into the ring. The robots, armed with saws, pulverizers, ramrods and more, really just go at each other for our entertainment. Nearly as interesting as the destruction that takes place onscreen is what goes on behind the scenes—what goes into bringing the violent bots to life.
Each robot that takes the ring in BattleBots is painstakingly engineered and manufactured by a specialized team to meet certain requirements. For one, the robots can’t weigh more than 250 lbs and they must be equipped with at least one independently-powered weapon. They must also be impact resistant, precise and fully controllable. To add an extra challenge to this year’s BattleBots edition, teams were also given the shortest build calendar to date, with only a month to build their bots.
To overcome the strict time limitations imposed, Team SawBlaze, a Boston-based team made up of MIT engineering students and graduates, turned to Desktop Metal to use its Studio System equipment to rapidly and cost effectively produce an important part for its flame-throwing, saw wielding robot.
It was Jamison Go, a mechanical engineer at Desktop Metal and the captain of Team SawBlaze who realized that Desktop Metal’s additive manufacturing technology could help his team to build its robot without compromising quality and leveraging design flexibility, rapid production, lower costs and high-performance materials.
Specifically, Desktop Metal’s Studio System was used to manufacture a backstop part for the robot, a sub-assembly that straddles and protects the diamond abrasive rescue saw blade. The critical part, which had to sustain various loads, needed to be stiff, strong, hard and resistant to corrosion and heat. Importantly, the part also had to be as lightweight as possible to stay within weight limits.
“In contrast to most BattleBots robots that apply brute force, SawBlaze applies precision damage,” said Go. “This strategy is much more difficult to execute. Working against a limited development timeline, our processes must be extremely efficient in order to achieve an optimized and consistent strength-to-weight ratio as the robot moves and comes into contact with the competition.”
Opting to use Desktop Metal’s 3D printing system over other manufacturing options (such as CNC machining or DMLS), Team SawBlaze succeeded in building a lightweight backstop that integrated cut-outs into its design as well as closed-cell infill to reduce material usage and weight. The part was printed in two ends out of AISI 4140 low-alloy steel and were fastened to each end of a metal crossbar.
In the end, the part was delivered in just three days and cost only $56. Desktop Metal compares the process to using DMLS through a third party which would take two weeks and cost $1,285 and using a CNC machining service which would take two to three weeks and costs upwards of $600. Overall, the team was able to achieve a 90-95% reduction in both part cost and weight.
The biggest question, of course, is how well did Team SawBlaze’s robot perform in the ring with the 3D printed part. The answer? Very well. SawBlaze took out its first competing robot in just 94 seconds and went on to win a number of other battles.