Russian cosmonauts conduct second spacewalk to activate European Robotic Arm

by Joseph Navin

On April 28, Russian cosmonauts Oleg Artemyev and Denis Matveev ventured outside the International Space Station in the second planned spacewalk to activate the European Robotic Arm (ERA). This follows last week’s spacewalk, where astronauts removed covers from the arm and installed a control panel.

The spacewalk is known as VKD-53 began at 14:58 UTC. Both Artemyev and Matveev were scheduled to spend around six hours and 45 minutes outside the ISS, with final EVA time clocking in at seven hours 42 minutes.

This spacewalk saw the first movement of the ERA as it is maneuvered out of launch position.

VKD-53 Spacewalk:

Prior to the EVA, both Artemyev and fellow Roscosmos cosmonaut Sergey Korsakov prepared for the spacewalk. During practice over the weekend, Korsakov simulated operating the European Robotic Arm.

The two cosmonauts – Artemyev and Matveev – began the spacewalk inside the Poisk module, which has served as the airlock for the Russian segment of the ISS since the retirement of the Pirs module. Once both cosmonauts egressed the Poisk module, they used a Strela crane to reach the Nauka module.

Once there, both cosmonauts used existing handles on the exterior of Nauka to get to the European Robotic Arm, which was stowed and secured in launch position on the side of the module. One of the first tasks was to remove a covering on the lower section of the arm.

Render of Nauka with the ERA visible – via NASA

The launch position for the ERA was nicknamed the “Charlie Chaplin” configuration by ERA engineers due to the resemblance of the configuration to the comedic stance of the English actor Charlie Chaplin.

Both Artemyev and Matveev then worked on unstowing the arm from this position. Later on, the ERA was extended and was commanded to attach to existing interfaces on Nauka. The ERA was then moved from the aft side of Nauka, where it was stowed during launch, to the forward-facing side of Nauka.

During this operation of the ERA, Korsakov controled the arm from inside the Russian segment.

Following this activity, both Artemyev and Matveev used the Strela crane to ingress the hatch on the Poisk module. After the hatch was closed, the interior of the Poisk module will once again be pressurized.

For Artemyev, VKD-53 was his fifth spacewalk and Soyuz MS-21 is his third flight into space. VKD-53 was the second spacewalk for Matveev, who is currently on his first spaceflight.

During the spacewalk, Artemyev wore Orlan-ISS Spacesuit No. 5, and Matveev used Orlan-ISS Spacesuit No. 4. Artemyev’s suit featured two red stripes, while Matveev’s suit featured two blue stripes.

Oleg Artemyev waves from outside the International Space Station during the spacewalk on April 18. Credit: NASA.

Both Roscosmos and Soviet space programs have used versions of the Orlan spacesuit since 1977. Cosmonauts first used the suit aboard the Salyut 6 space station during Expedition EO-1.

The first in this series of spacewalks to activate the European Robotic Arm occurred on April 18 and was conducted by both Artemyev and Matveev. The next spacewalk in this series will be conducted by Artemyev and Italian astronaut Samantha Cristoforetti of the European Space Agency (ESA), who arrived at the ISS on Crew-4.

That third spacewalk in this series is scheduled to occur in mid-May.

Artemyev, Matveev, and Korsakov arrived at the orbiting outpost on Soyuz MS-21, which launched on March 18 from the Baikonur Cosmodrome in Kazakhstan. They docked to the Russian Prichal module later that same day. Soyuz MS-21 was the first crewed spacecraft to dock to Prichal following its arrival at the ISS in November 2021.

All three crew members – Artemyev, Matveev, and Korsakov – attended the same technical university called Bauman Moscow State Technical University. The three cosmonauts are a part of ISS Expedition 67.

The European Robotic Arm
The European Robotic Arm (ERA) is the third robotic arm to be installed on the ISS, following the Canadarm2 and the Japanese Experiment Module Remote Manipulator System (JEMRMS), which are both located on the US Orbital Segment (USOS) of the ISS.

An infographic on the European Robotic Arm. Credit: European Space Agency.

The ERA is the first robotic arm on the Russian Orbital Segment on the ISS. The arm will supplement the existing Strela cranes on the Russian segment and will assist cosmonauts during future Russian EVAs. It can be operated from inside and outside the Station and by controllers on the ground.

Unlike the Canadarm2, the ERA will not be used to berth spacecraft arriving at the Station as Canadarm2 does for the Cygnus and HTV spacecraft.

Both the ERA and Nauka launched into space onboard a Proton-M rocket from the Baikonur Cosmodrome on July 21, 2021, and subsequently arrived at the ISS on July 29.

Later in 2021, French astronaut Thomas Pesquet of ESA and Russian cosmonaut Peter Dubrov of Roscosmos worked to configure interior controllers for the arm and software.

The ERA has an arm length of 11.3m and it can reach up to 9.7m. At launch, the arm had a mass of 630kg. The arm also has seven joints that provide roll, yaw, and pitch movements.

The robotic arm was designed and constructed by Airbus Defense and Space Netherlands. It was constructed of aluminum and carbon fiber. The ERA took around two decades of development, testing, and construction before launching due to technical issues and delays of Nauka.

Lead image: Roscosmos cosmonauts Oleg Artemyev and Denis Matveev are seen outside the Nauka module during VKD-52 on April 18. Via NASA

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