SBIR Phase I: Twin Bearingless Motor with Integrated Thrust and Radial Suspension

The broader/commercial impact of this Small Business Innovation Research Phase I project is the development of more reliable, efficient, and maintenance-free electric motors for industrial systems. Mechanical bearings are a leading cause of failure in motors used in compressors, pumps, and other energy-intensive equipment, creating downtime, high maintenance costs, and energy losses. This project will address the challenge of eliminating mechanical contact inside motors by enabling stable magnetic support of rotating shafts without physical bearings. The project will investigate new ways to generate and control axial forces inside electric motors, which is a major barrier to fully eliminating mechanical bearings. These advances could reduce energy consumption, lower operating costs, and improve the reliability of critical infrastructure such as heating, cooling, and industrial systems. This project will investigate a high-risk, hard-to-replicate approach for generating controllable axial force directly within an electric motor, enabling full magnetic support of a rotating shaft without mechanical bearings. Conventional bearingless motors can stabilize shafts radially but lack the ability to generate sufficient axial force, requiring separate thrust bearings or auxiliary systems. The primary innovation explored in this work is a motor architecture that produces axial force using the same electromagnetic structures that generate torque, eliminating the need for dedicated thrust components. The scope of the project includes the design, modeling, and experimental validation of a motor system capable of producing independently controllable torque, radial and tilting forces, and axial force. The intellectual contribution of this work is the development of new magnetic field configurations and control strategies that intentionally create axial force while maintaining torque and radial force performance and stability. This represents a departure from traditional motor designs which intentionally avoid axial forces. The proposed methodology combines analytical modeling, three-dimensional electromagnetic simulation, and hardware prototyping. The project will develop physics-based models to predict force generation, validate these models using numerical simulation, and construct prototype hardware to experimentally measure axial and radial force performance. Control methods will be evaluated to demonstrate independent force regulation without degrading torque output. The results of this work will establish the feasibility of fully magnetically supported motors and provide a foundation for future development of oil-free, friction-free, high-reliability rotating machinery. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.