Combat Robotics - “RGBeater”
With my second 15lb combat robot “RGBeater”, my goal was to optimize the mechanical design as much as possible while maintaining a sleek form factor. My design combines a heavy hitting “beater bar” weapon optimized for energy transfer with a unique omni-wheel drive that allows sliding to minimize the weapon’s gyroscopic effect and opponent engagement. Using Fusion 360’s shape optimization along with material selection (Grd 6 Titanium for wedges, UHMW polyethylene for armor), I was able to design mass-efficient structures informed by physics calculations (such as the 37 degree wedge maximizing vertical impulse). Each component was sourced based on reliability, strength and weight, including titanium fasteners and base plate and brushless outrunner motors. Our manufacturing partner machined the beater bar using Wire EDM and waterjetted the chassis frame components using my GD&T drawings and DXF files, while I completed the machining on a CNC mill using Fusion 360 CAM software and led our build team in final assembly at the shop.
RGBeater in Action
Near-Full assembly of RGBeater
Design process of using Fusion 360 shape optimization for 2D weight reduction for all structural members: Finite Element Analysis, application of results into final CAD design, and manufacturing with via waterjet + Tormach PCNC 1100 CNC Mill
Full bottom-up CAD of RGBeater
Drafting for CNC mill post-processing of the waterjetted cross support
Wire EDM machined weapon. 4140 Steel Hardened to 45 HRC. Optimized for energy transfer and MoI/kg, 45.2% more mass efficient than a simple bar.
Calculating metrics to inform the design, such as balancing engagement with Kinetic Energy (~1 g of TNT), choosing a drive gear ratio to balance max speed and acceleration, and tuning the drive voltage to prevent gyroscopic precession flipping the robot.
Perspective view of RGBeater CAD