NASA Docking System

NASA Docking System (active androgynous variant on top, permanently passive variant on the bottom). 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.

The NASA Docking System is NASA's implementation of the International Docking System Standard (IDSS), an international spacecraft docking standard promulgated by the International Space Station Multilateral Coordination Board. NDS is a spacecraft docking and berthing mechanism used on the International Space Station (ISS), the Boeing Starliner, and the Orion spacecraft. The international Low Impact Docking System (iLIDS) was the precursor to the NDS. NDS Block 1 was designed, built, and tested by the Boeing Company in Huntsville, Alabama. Design qualification testing took place through January 2017.

Using NDS, NASA developed the International Docking Adapter (IDA) to provide two IDSS-compliant docking ports on the ISS. The IDAs were delivered to the ISS starting in 2016. Each of two existing Pressurized Mating Adapters has an IDA permanently attached, so the former PMA function is no longer available for visiting spacecraft. Since 2019, visiting spacecraft that implement IDSS dock to the NDS ports on the IDAs. These include Crew Dragon, Cargo Dragon 2, and the Boeing Starliner.