Boeing Design Competition

Boeing is a global leader in aerospace innovation, known for pushing technological boundaries in aviation. As part of a Boeing-sponsored competition at Cal Poly, our team was tasked with developing a robotic system to assist with aircraft cabin cleaning between flights. The intention was to create a ceiling-mounted robot that could travel along the interior of the aircraft and aid in reducing turnaround time by automating parts of the cleaning process. This project focused on designing and prototyping the gantry system, drive mechanism, and core sensing technologies to ensure safe and precise movement within the aircraft.

I served as the lead mechanical designer and manufacturing lead for the project, handling both CAD design in SolidWorks and the manufacturing strategy to ensure the system was functional, manufacturable, and efficient. I designed the ceiling-mounted rail system, custom wheel assemblies, and powertrain, making sure the robot could move smoothly while blending seamlessly into the aircraft interior. I also worked on sensor integration for collision avoidance and positioning, ensuring the system could operate safely in close proximity to flight crew members.

The final product was a fully functional robotic system capable of traversing the length of the aircraft using a custom rail system, detecting obstacles in real time, and operating safely within its environment. While the cleaning mechanism was not yet implemented due to time constraints, the motion and sensing systems were successfully completed and tested. Boeing engineers reviewed our design and approved our approach as a viable direction for further development.

The structural backbone of the system was the ceiling-mounted gantry, which needed to be lightweight, structurally sound, and low-profile to ensure it wouldn’t interfere with passenger movement or flight crew operations. The custom V-rail design I developed provided both structural rigidity and precise alignment, while also maintaining an aesthetic integration with the aircraft interior. When painted to match the ceiling, the rails appeared as simple crown molding, making the system discreet when not in use.

The motion system was a critical aspect of the design, ensuring smooth, controlled movement along the aircraft ceiling. I developed a custom wheel system specifically designed to fit within the V-rails, using TPU 3D-printed wheels that could absorb imperfections in the rails while maintaining stable, self-aligning movement. This ensured the robot would stay perfectly centered within the tracks without the need for additional guiding components.

The drive system used a belt-driven stepper motor to move the robot along the rails. To prevent belt slippage, we implemented a tensioning mechanism with additional pulleys, ensuring at least 180 degrees of belt contact with the drive pulley. I performed calculations to determine the appropriate motor size based on the robot’s weight, required acceleration, and speed targets, ensuring that the system could move efficiently without excessive power draw.

Since the robot would be operating near flight crew members, safety was a priority. A set of four ultrasonic sensors was mounted at the lowest points of the robotic carriage, providing a cost-effective and reliable way to detect obstacles. These sensors ensured that if anything was in the robot’s path, movement would stop immediately until the obstruction was cleared. This real-time response helped guarantee that the system could function without risk of accidental contact with personnel or equipment.

An additional layer of safety and precision came from four high-precision lidar sensors, each mounted at a wheel position. These sensors played a dual role in ensuring the system's accuracy. They could detect obstacles or foreign objects placed on the rails, preventing damage to the robot or the aircraft. More importantly, they provided real-time position tracking by measuring distances along the length of the aircraft. The system was programmed to recognize the full aircraft length, allowing it to determine its exact location at all times. By averaging the readings from all four lidar sensors, the system could filter out anomalies and maintain an extremely accurate position reference. If any sensor provided an inconsistent reading, the system could detect the error and ensure no incorrect movement commands were executed.

The robot’s power and control systems were designed for simplicity and reliability during prototyping. The system ran on two lead-acid batteries wired in series (24V) to ensure consistent power output throughout its operation. An Arduino Mega was used to process sensor inputs, handle motor control, and manage emergency stop functions, providing a straightforward yet effective control system. While the Arduino-based approach worked for testing, it had limitations in handling both stepper motor control and multiple sensors simultaneously, leading to the conclusion that future iterations would benefit from either a dedicated stepper motor controller or a switch to a DC motor system with external position feedback.

The next step for the project would be the development of the actual cleaning mechanism, which was the primary goal of the Boeing challenge. While the system’s mobility, safety features, and structural framework were successfully implemented, a fully integrated cleaning system would require further design, testing, and optimization. Future development would focus on determining the most efficient cleaning method that could operate within the confined aircraft space while maintaining the speed and safety requirements of the airline industry.

The stepper motor system provided precise movement but had processing limitations when running alongside multiple sensors on the Arduino Mega. A future version would require either a dedicated motor controller for improved performance or a simplified DC motor system with external positioning feedback. This change would enhance responsiveness, reduce complexity, and ensure the system could scale beyond a prototype phase.

The prototype successfully demonstrated core functionality, but the manufacturing methods used were not ideal for large-scale production. The use of off-the-shelf components like 3D printer rails and welded structures made development easier but would need to be replaced with custom, purpose-built components. Switching to a custom extruded aluminum rail system instead of welded sheet metal would improve durability, ease of installation, and consistency in manufacturing, ensuring that future versions of the robot could be more easily implemented in real-world aircraft environments.