Gemini/Agena docking mechanism
The Gemini/Agena docking mechanisms utilize simple mechanical elements to provide a capability for initial engagement between two orbiting vehicles. The docking mechanisms then rigidize the attachment in a manner suitable for subsequent maneuver with the Agena propulsion system. Finally, the mechanisms provide a capability for disengaging and repeating the entire docking cycle. The mechanical elements used are found in daily terrestrial applications.
Agena docking↗