EHA hydraulic actuator for the Five-hundred-meter Aperture Spherical radio Telescope of the National Astronomical Observatory of China

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) of the National Astronomical Observatory of China is the world's largest single-aperture telescope. The hydraulic actuator, which powers and controls FAST's aperture movement, is crucial to FAST’s astronomical observation capabilities and overall performance. Uranus won the bid by outshining several formidable competitors worldwide with its exceptional and innovative EHA technology solution. The actuator, with no global precedents to reference, presented extreme development challenges. Drawing on more than 30 years of hydraulic technology expertise, Uranus has successfully navigated these challenges, dedicating two years to ensuring excellence through every phase, from design and prototype development to factory simulation testing. After three years of trial operation, the actuator successfully passed the national formal inspection and won the Outstanding Contribution Award from the National Astronomical Observatory.

FAST actuators feature a highly integrated electromechanical and hydraulic design, offering capabilities such as source switching, tracking, precise positioning, position retention,  passive travel on fault, overload protection, manual operation, electromagnetic shielding, and status monitoring. The 2,225 actuators working in pressure, speed, and displacement, can be independently adjusted at any time, operating synchronously. This innovation overcomes the technical challenges of EHA multi-point precise synchronous control, establishes a benchmark in such technology, and advances the adoption of EHA in intelligent digitalization applications, contributing to China's fundamental scientific research. The EHA actuator has been awarded 6 national invention patents, one utility model patent, and one design patent.