QAZAQ GREEN.  The Southwest Research Institute (SwRI) has developed an advanced structural technology that enhances the rigidity of deployable spacecraft components, enabling precise autonomous docking maneuvers. The new Parallelogram Synchronized Truss Assembly (PaSTA) system is being integrated with solar arrays on the Astroscale U.S. Refueler spacecraft, as well as into two deployable booms for another SwRI project.

The Astroscale U.S. Refueler, a 300-kilogram spacecraft, will perform the first hydrazine refueling mission above geostationary orbit for the U.S. Space Force — marking the first on-orbit refueling operation to support a U.S. Department of Defense asset. SwRI is responsible for building, integrating, and testing the spacecraft, which requires highly stable solar arrays to maintain precision during docking.

“Vibrations can disrupt docking operations, so stiffness is critical,” said SwRI Institute Engineer Randy Rose, inventor of the patented PaSTA technology. “PaSTA provides the rigidity necessary for accurate spacecraft maneuvers.”

The PaSTA framework acts as a structural backbone, keeping solar arrays stable once deployed. On the Astroscale U.S. Refueler, the arrays extend 4.5 feet from the spacecraft. On another SwRI spacecraft, each array will span 20 feet and generate up to 5,000 watts of power while maintaining the same precision.

According to Ryan Rickerson, head of SwRI’s Deployable Structures Section, PaSTA ensures all components deploy in sync, eliminating unpredictable hinge movements typical of conventional designs. The technology enables smooth, controlled unfolding even under challenging testing conditions on Earth.

Testing and integration of the PaSTA-equipped arrays are currently in progress at SwRI’s facilities in San Antonio, Texas.