NASA Docking System

Each of two existing Pressurized Mating Adapters has an IDA permanently attached, so the former PMA function is no longer available for visiting spacecraft.

[2] In form and function NDS resembles the Shuttle/Soyuz APAS-95 mechanism already in use for the docking ports and pressurized mating adapters on the International Space Station.

There is no compatibility with the larger common berthing mechanism used on the US segment of the ISS, the Japanese H-II Transfer Vehicle, the original SpaceX Dragon, and Orbital Sciences' Cygnus spacecraft.

[10] Boeing's proposal was the Soft Impact Mating and Attenuation Concept (SIMAC), a design originally conceived in 2003 for the Orbital Space Plane (OSP) Program.

[11] In August 2014, Boeing announced that the critical design review for the redesigned NDS had been completed.

[12] Following this change the IDSS was modified (to rev D), so the new design of the NASA Docking System is still compatible with the standard.

[13] IDA-2 was delivered successfully on SpaceX's CRS-9 mission in July 2016, and then installed on PMA-2 in August of that year during a spacewalk by Jeffrey Williams and Kathleen Rubins as part of Expedition 48.

NASA Docking System (active androgynous variant on top, permanently passive variant on the bottom). [ citation needed ] Mechanical latches (visible on the guide petals) in the active ring clamp onto the passive section for contact and capture
IDAs shown connected to PMA-2 and PMA-3 on the Harmony node.
Testing of the X-38 Low-Impact Docking System.
Image showing the design changes from IDSS revision b to c