NASA was so concerned that vibrations reverberating from deployment of Bigelow Aerospace’s Expandable Activity Module (BEAM) could damage the International Space Station (ISS) that the agency initially pursued a manual pressurization technique of “five seconds on, 15 minutes off,” company founder Bob Bigelow told Defense Daily Friday.
Bigelow said Thursday’s first, but failed, attempt to properly pressurize BEAM had nothing to do with the spacecraft. Instead, he said it stemmed from a NASA computerized modeling effort that did not match how the spacecraft was expanding in reality. Bigelow said this drove NASA to stop Thursday’s expansion process as soon as the expansion pattern didn’t match the agency’s model profiles.
In response, Bigelow said NASA pursued a manual pressurization technique in which the agency would pressurize for five seconds, then wait 15 minutes to see the effect. NASA would then repeat this process, but Bigelow didn’t think this was a good idea. He instead believed NASA would have been better keeping the airflow constant as he said BEAM is so powerful, its hull requires some “encouragement” to expand itself. Bigelow said the hull on BEAM is stronger than the aluminum hulls on ISS.
“If you take a small breath of air, the hull doesn’t notice much until you get to a certain point,” Bigelow said.
This is one of two possible ways to pressurize BEAM. Bigelow said the other is to use BEAM’s full complement of onboard air tanks with automatic apparatus that can be controlled to the rate of expansion. NASA, he said, did not use this approach. The five seconds on, 15 minutes off approach, Bigelow said, used a simple valve attached to BEAM’s bulkhead that features a control panel that allows an astronaut to press a button and get five second bursts of air that come from ISS as the station was pressurized and BEAM was not.
NASA on Saturday successfully expanded BEAM to its full volume, according to an agency statement, beginning two years of tests to demonstrate the new expandable technology. NASA said 25 “pulses” of air were introduced into BEAM to get to its full capacity of 1,400 mass kg and 16 cubic meters. NASA did say it used BEAM’s eight air tanks to complete pressurization Saturday.
BEAM leak checks are underway, NASA said, and will continue until astronaut Jeff Williams gets approval to enter the module on June 6. Williams will install sensors inside BEAM to measure its environment.
Bigelow said BEAM is now “open for business” as NASA told him to make BEAM available for payloads. Bigelow said if a company had roughly $50,000 or $100,000, depending on the complexity of the payload, the company is ready to help facilitate their payloads.
In other Bigelow Aerospace news, Bigelow said he hopes to start taking deposits and reservations by late 2017 for the B330, a larger habitat than BEAM at 330 cubic meters. He said he wants to have two B330s ready to deploy sometime in 2020.
Expandable habitats are designed to take up less room on a spacecraft, but provide greater volume for living and working in space once expanded. This first test of an expandable module in BEAM will allow investigators to gauge how well the habitat performs and, specifically, how well it protects against solar radiation, space debris and the temperature extremes of space.
NASA did not respond to a request for comment by press time Tuesday.