Engineering an Underwater Drive System for the Macao Pagoda
The greatest challenge of the Macao Pagoda project was not the motor itself, but ensuring long-term reliability in a submerged environment.
Instead of relying solely on dynamic shaft seals—which inevitably wear over time—we designed the system to minimize their number. The batteries and control electronics were installed in one sealed enclosure, while the motor and gearbox were housed in a separate compartment connected through sealed electrical and pneumatic feedthroughs.
To further improve reliability, all enclosures were maintained under slight positive air pressure using a scuba cylinder and a specially adjusted pressure regulator. In the event of a seal failure, air escaped outward instead of allowing water to enter, while pressure loss or air bubbles provided immediate leak detection.
The control switches were actuated magnetically, eliminating mechanical penetrations through the enclosure and removing additional dynamic seals.
This innovative architecture provided the reliability and safety required for continuous underwater operation, ensuring years of dependable service in a permanent public attraction where any unexpected failure would have interrupted performances for thousands of visitors.