Disney’s BD-X droids have become a major attraction for Star Wars fans visiting Galaxy’s Edge. The small robots wobble through the parks with lifelike movements, reacting to guests and showing emotion through body language rather than speech. Disney has kept the technology closely guarded, leaving fans with little chance of seeing how the machines actually work.

That exclusivity pushed one engineering student to build his own version from scratch.

Kayden Knapik recreated a BD-X-inspired robot as part of his bachelor’s thesis project using consumer-grade hardware, home-built components, and open-source software. Despite limited robotics experience and no corporate budget, he produced a fully functioning bipedal droid that can walk, balance itself, respond to commands, and express emotion through moving antennas.

Consumer hardware approach

Knapik built the robot using parts available through online retailers instead of expensive industrial systems. Sixteen Robstride motors power the droid’s joints and provide enough torque for stable walking motions. The setup cost about $2,800, which sits far below the price of comparable proprietary robotics hardware.

He paired the motors with a standard 40-volt lithium-ion lawn mower battery to simplify charging and replacement. Sensors inside each joint track movement and positioning in real time, while an inertial measurement unit monitors tilt and orientation. Together, those systems help the robot maintain balance while moving across different surfaces.

Most of the outer structure came from a standard home 3D printer. Knapik initially used reinforced PETG plastic parts, but repeated stress tests cracked the hip assemblies under full motor load. He later replaced the high-stress sections with CNC-machined aluminum components, which solved the durability issue without requiring a full redesign.

Training through simulation

The robot’s movement system relies heavily on software rather than traditional hand-coded walking routines. Knapik created a digital replica of the droid inside NVIDIA’s robotics simulation platform and trained it through millions of virtual movement attempts.

During training, the simulation constantly altered variables such as weight distribution, surface grip, and motor timing. Those randomized conditions forced the robot to adapt to unstable environments and unexpected movement patterns. Once the training finished, Knapik transferred the learned behavior directly to the physical machine.

The first real-world tests exposed timing mismatches between the simulation and the actual motors, which caused awkward movement. Knapik refined the delays and adjusted the control system until the virtual model aligned more closely with the physical hardware. The robot eventually gained the ability to walk forward and backward while maintaining balance after minor pushes.

The droid also responds to voice commands and uses animated antenna movements to create more personality during interactions.

Open-source droid project

Knapik has published the CAD files, assembly instructions, and training software through a public GitHub project called BDX-R. The open-source release allows robotics hobbyists to build their own versions using accessible tools and materials.

He has already started designing a smaller version that could reduce the total cost to roughly $400.

The project reflects a broader shift in robotics development across the United States and beyond. Hardware that once remained limited to major entertainment companies and research institutions has become increasingly accessible through affordable motors, desktop manufacturing tools, and open-source AI software.