NASA Implementing New And Old Technologies For Crew Access Arm
September 24, 2012

NASA Implementing New And Old Technologies For Crew Access Arm

Lawrence LeBlond for - Your Universe Online

NASA engineers in Florida are coalescing traditional and new technologies to design a crew access arm on a mobile launcher at Kennedy Space Center (KSC) that will be used for the space agency´s Orion spacecraft, reports Linda Herridge, correspondent for NASA´s KSC.

Engineers with the Ground Systems Development and Operations Program at KSC are working diligently to design and develop the 60-foot hydraulic arm that will be similar to the one used during the Apollo missions. Kelli Maloney, a mechanical design engineer for the center´s Engineering Directorate, said the arm will have two levels and incorporate hardware from both the Apollo and Space Shuttle programs.

Orion will be the most advanced manned spacecraft ever developed by NASA. It is being designed to be able to carry astronauts farther into space than any craft has ever done before. The Space Launch System (SLS) is also designed to be flexible for launching spacecraft for both crew and cargo missions, and will expand human´s presence across the solar system. Orion is scheduled to make its first launch in 2017.

The crew access arm will include a new “White Room” on the upper level. This area will provide access to the Orion crew module and will contain a six-foot-long access platform, nicknamed the “diving board,” that will extend from Orion to the crew module. A lower-level walkway will provide access to two panels on the spacecraft´s service module.

Engineers will use design technology from the inflatable dock seal on the space shuttle´s orbiter access arm, as well as storage cabinets and safety equipment from the shuttle-era White Room, according to Maloney.

Apollo-era hinges will be used to rotate the access arm out to the crew module, she added. These hinges will be retrofitted with new digital encoders to accurately obtain the arm´s position. “This information will be fed back to the Program Logic Controllers in an electrical room on the Mobile Launcher tower in order to achieve precise control of arm position,” Maloney said.

“It´s a challenge, because you have to think about every detail,” Maloney added. “It´s very diverse.”

Engineers are using 3D visualization tools to view the concept throughout the design process. The design team is reusing Apollo-era controls, scanning them and uploading them into a special 3D design software program. The process saves time and costs, Maloney noted.

“Having access to 3-D scanning capabilities is very helpful so that we can see how the design will fit into the existing structures, such as the mobile launcher, the Vehicle Assembly Building and Launch Pad 39B,” Maloney said.

The new innovations will also allow the White Room to be removed and replaced further up on the arm to accommodate access to larger cargo vehicles and future manned vehicles.

The NASA design team, which also consists of Engineering Services Contract engineers, expect to have design review nearly two-thirds complete by January, with design work continuing throughout 2013. Fabrication of the arm could begin in 2014, with initial testing coming as early as 2015.