According to NASA, Bresnik and Vande Hei will replace one of two Latching End Effectors (LEE) on the station's robotic arm, Canadarm2.
Astronauts Mark Vande Hei, left, and Randy Bresnik work on the International Space Station.
"The second and third spacewalks will be devoted to lubricating the newly installed end effector and replacing cameras on the left side of the station's truss and the right side of the station's US Destiny laboratory", Nasa said. Joe Acaba arrived at the space station September 12 for his third mission to space.
This bundle of latches - more than a meter long - is used to grab visiting spacecraft, and provides power and data.
They replaced one of two Latching End Effectors (LEE) which had lost the ability to grip effectively, said the USA space agency. Vande Hei, EV-2, is wearing an unmarked suit and is using helmetcam 20.
The spacewalk will be the first out of their three planned for October that having the aim to get the Canadian robotic arm in good shape for doing effective work outside the ISS. That way, the arm can move like an inchworm across the sprawling structure.
The Canadarm 2 measures 57.7 feet long, weighs almost 4,000 pounds, has seven joints and, in the weightless environment of low-Earth orbit, can move large spacecraft and modules from one point to another.
The Canadian-built arm has been in orbit for 16 years.
Canadarm2 was launched in 2001, so it's starting to experience some wear and tear. While this will be the first-ever spacewalk of the latter, it will mark the third one of Bresnik. The second spacewalk is scheduled for October 10, and the third for October 18. It hasn't caused any slowdown in standard ISS operations, and the crew keeps a spare LEE around in case of just such an emergency.
Similar to the International Space Station, this new space station will be open to to astronauts and cosmonauts globally.