OSIRIS-REx – Testing In Progress
Posted by Annie Wargetz
17-07-2015 15:12 CDT
This article originally appeared at Dante Lauretta's blog and is reposted here with Annie Wargetz's permission. -Ed.
The OSIRIS-REx spacecraft is in the assembly and testing phase at Lockheed Martin’s facility outside of Denver, Colorado. The instruments have begun to arrive at the facility, with OTES and OVIRS being delivered in the past weeks.
While the OLA, OCAMS, and REXIS instruments continue working towards their deliveries, other hardware onsite at Lockheed is undergoing testing prior to installation. The hardware is put through tests here on Earth prior to launching into space.
One of the tests the hardware is put through is called vibration testing. Spacecraft are subject to high levels of vibrations during launch. The high level of noise emitted from rockets, the vibrations from the thrust of the rocket, and the atmospheric environment of launch all contribute to these vibrations the spacecraft experience during ascent.
Another series of tests includes placing the hardware into chambers that are sealed off and simulate the temperatures and pressures of space. These tests are referred to as the Thermal Vacuum tests, or TVAC tests.
Let’s take a look at some of the specific testing that the different pieces of hardware are undergoing.
The Sample Return Container
The Sample Return Container (SRC) is responsible for housing the sample once it is collected from Bennu and returning it to the surface of the Earth. Since the SRC will be re-entering Earth’s atmosphere after being released from the spacecraft itself, it must be balanced so that the re-entry trajectory is as straight as possible.
The SRC is spun at high speeds while being held in different orientations in order to test the balance of its mass.
In addition to the spin tests, the SRC has also undergone vibration testing. The entire spacecraft experiences a high level of vibrations during the climb into space, so testing the individual components of the spacecraft allows for checking them out prior to launch.
The SRC also has gone through thermal vacuum, or TVAC, testing which exposes the hardware to the extreme temperatures and low pressures of space.
The TAGSAM Sampling Mechanism
These pictures show the progress being made on the TAGSAM instrument which will be responsible for executing the sampling sequence. The arm will extend from the spacecraft, placing the sample head on the surface of Bennu so that the sample can be collected.
Once the TAGSAM instrument is mounted to the vibration testing apparatus, the vibration testing is conducted.
In addition to the vibration testing, the TAGSAM instrument has been undergoing functional testing. Large balloons filled with helium are affixed to the instrument to offset the effects of gravity on the instrument. TAGSAM is then moved to test its range of motion.
The High Gain Antenna
The High Gain Antenna (HGA) is the most powerful communications antenna on the spacecraft. It will play a fundamental role in communicating with Earth during the mission via NASA’s Deep Space Network. It is also undergoing testing in preparation for installation onto the main spacecraft structure.