BattleBots is a popular American television series that sees teams of skilled engineers putting up their specially designed combat robots against each other for the championship. One such team was Team SawBlaze, where they integrated the design flexibility and rapid iteration capabilities afforded by metal 3D printing brand, Desktop Metal.
Several factors have to be considered when designing the robot for battle as well as to overcome arena obstacles. Team members thus have to demonstrate their creativity, engineering skills, strategy, and driving ability, so as to maximize the robot’s performance while trying to overcome the shortest build time of one month for the 2018 season.
As opposed to other BattleBot robots that fight using brute force, Team SawBlaze uses a precision damage strategy that was more difficult to execute, of which their weaponry included a diamond abrasive rescue saw blade and flame-thrower.
One key component was the backstop: a sub-assembly that straddles and protects the blade. The backstop must withstand stiffness, strength, hardness, corrosion resistance, and heat resistance as it withstands continuous hits during battle.
With limited time and budget, the method of fabrication was crucial especially for customized parts like the backstop. Team SawBlaze identified in-house metal 3D printing from Desktop Metal as being the most feasible option.
- CNC Machining – 2 -3 weeks to produce, costing $606
- Direct Metal Laser Sintering (DLMS) – 2 weeks to produce, costing $1,285
- Studio System* – 3 days to produce, costing $56
Team SawBlaze printed two end pieces of the backstop using AISI 4140 low-alloy steel, before fastening them together with a metal-cross bar. The parts were designed with “cut-outs” and a closed-cell infill pattern throughout to eliminate excess material and reduce its weight. This technique was impossible to accomplish with other manufacturing processes.
By leveraging on the benefits of in-house metal 3D printing, Team SawBlaze was able to achieve a 90-95% part cost reduction while developing a lightweight combat robot that adhered to the 250lbs (113kg) weight restriction.
* The Studio System+ has since replaced the Studio System with new enhanced features.