Spacewalkers step out for robotic system

Philippe Perin, top, and Franklin Chang-Diaz attach a portable foot restraint Chang-Diaz will use to anchor himself to a robotic arm during the spacewalk.

HOUSTON, Texas (CNN) -- The crew of the space shuttle Endeavour began installing new equipment Sunday on the international space station.

Mission specialists Franklin Chang-Díaz, an American, and Philippe Perrin, a Frenchman, went on a spacewalk as part of the master plan to assemble and expand the space station.

The primary goal of the spacewalk is to install a Power and Data Grapple Fixture, a key component of the Mobile Servicing System, to the space station.

The MSS is a robotic system that will play a key role in space station assembly and maintenance, helping crew members move equipment and supplies around the station.

The pair also unloaded protective shields, known as Service Module Debris Panels, from Endeavour's cargo bay and stow them for a future spacewalk when they will be installed on the space station.

CNN NewsPass VIDEO Space shuttle Endeavour crew members take the first of three planned space walks (June 9) Play video   MISSION GUIDE A CNN.com Endeavour mission guide  has crew bios, a mission timeline and more.

It was the first of three spacewalks that will be carried out on the mission.

Chang-Díaz, 52, has been on six space flights, while Perrin, 39, is making his first voyage. Sunday's spacewalk was the first for each of them.

Endeavour docked with the space station Friday after nearly a week of launch delays. The shuttle brought supplies and a relief crew.

The space station's Expedition Four crew -- two Americans and one Russian -- has been on board the station since December 7. The Expedition Five crew has two Russians and one American.