Mitsubishi Electric Corporation (TOKYO: 6503) has agreed with Orbital Sciences Corporation (Orbital) to supply Proximity Link System (PLS) components to guide Orbital’s Cygnus Spacecraft to the ISS on nine re-supply missions for NASA. The PLS components were originally developed for the H-II Transfer Vehicle (HTV) program by Mitsubishi Electric under contract with the Japan Aerospace Exploration Agency (JAXA).

Mitsubishi Electric will deliver the PLS components to Orbital between 2010 and 2014 in a deal valued at approximately US$66 million (6 billion yen), making it one of the largest contracts tying a Japanese company to NASA’s space exploration program. The Cygnus Spacecraft is under development by Orbital under a Commercial Orbital Transportation Services (COTS) Space Act Agreement with NASA. A demo flight is scheduled to launch in 2011 for a commercial cargo delivery system to ISS, following the retirement of the Space Shuttle in 2010. The eight subsequent missions will transport cargo to the ISS between 2011 and 2015 under Orbital’s Commercial Resupply Services (CRS) Contract with NASA.

The PLS components, composed of transponders, diplexers and data handling processors, are essential for rendezvous control between re-supply spacecraft and the ISS. When the re-supply spacecraft approaches the ISS, the on-board PLS initiates a signaling exchange with the PROX (Proximity Communication System), which is built into the ISS as a part of the Japanese Kibo Experimental Module, and guides the spacecraft in rendezvous and berthing with the ISS. Once the re-supply spacecraft is in close proximity to the ISS, it is grappled by the Space Station robotic arm and maneuvered to its final berthed position at the Nadir port of Harmony. The development and manufacture of the PLS components will be carried out at Mitsubishi Electric’s factory in Kamakura, Japan.