Skip to main content

Students crash rockets to develop new asteroid sample collection technique

In what at first glance seems like a terrible sense of direction, in March students from the University of Washington fired rockets from kites and balloons at an altitude of 3,000 ft (914 m) straight into the ground at Black Rock, Nevada: a dry lake bed in the desert 100 mi (160 km) north of Reno. This may seem like the ultimate in larking about, but it's actually a serious effort to develop new ways of collecting samples from asteroids.The test was part of the “Sample Return Systems for Extreme Environments” project. The idea is to find cheaper, more efficient ways of collecting samples from asteroids and hazardous areas on Earth, such as volcanoes and nuclear disaster zones, by using penetrators instead of soft landers or ground crews to hammer out sample cores.
According to the team, this would result in lower cost than soft landing techniques by reducing the velocity and vehicle mass needed to gather the sample, minimizing damage on impact, as well as being mechanically simpler. In the Nevada test, the penetrators were fired at the ground using rocket boosters to provide as much speed as possible at impact.
“We’re trying to figure out what the maximum speed is that a rocket can survive a hard impact,” says Robert Winglee, a UW professor of Earth and space sciences.
CAD rendering of a sample return spacecraft (Image: NASA)
The penetrator used in the test is 6 ft (1.8 m) long and 6 in (15.2 cm) in diameter. A carbon fiber airframe makes up the main body of the penetrator, which has a hardened solid tip with three sample ports. The tip must be harder than the material it penetrates, so it consists of aluminum or steel, depending on the target.
Behind the tip and lining the airframe is a crumple zone filled with Hexcel: a honeycomb aluminum material that collapses in an orderly fashion to absorb the force of impact. This protects the central collecting tube, which is attached to a tether developed in collaboration with Robert Hoyt of Tethers Unlimited Inc. of Bothell, Washington. The purpose of the tether is to control the impact speed of the penetrator and allow for sample return while helping to minimize the onboard electronics needed.
The way the penetrator works is that it is either dropped from space or, if used on Earth, fired into the ground using a rocket called a "sustainer" from a balloon or kite. When the penetrator hits, it's at 100 m/s (330 ft/s) and a force of 1,000 g’s on Earth and 1 km/s (0.6 mi/s) and 10,000 g’s if aimed at an asteroid.
Schematic of penetrator test vehicle
On impact, the penetrator burrows several feet into the surface and the force of impact rams sample material through the ports on either side of the nose, which funnels it to the interior sample return capsule that is attached by tether to a balloon or a spacecraft. The tether attached to the capsule is then used to reel in the capsule to the balloon or mothership to recover the sample.
The ultimate goal of the project is an unmanned sample collector spacecraft for studying asteroids or small moons. Using a solar-electric ion propulsion system, it would cruise to its target to conduct either a flyby or orbital survey. Once on station, the craft would fire a penetrator, which would burrow into the surface, then a tether would immediately haul the sample container back into the craft for return to Earth. The spacecraft would carry multiple penetrators for multiple sample collection.
According to Winglee, this year's test were successful, but the impact wasn't fast enough for a proper test, but it still won US$500,000 over two years from NASA Innovative Advanced Concepts. A second phase of testing in California is scheduled for next Northern Hemisphere summer and the year after with the goal of hitting the ground at Mach 2 (1,500 mph, 2,400 km/h).

Comments

Post a Comment

Popular posts from this blog

Connectify Dispatch combines multiple internet connections into high speed bandwidth

Connectify, a company known for software that can turn your computer into a wireless hotspot, is at work on a new project called Dispatch that will turn all internet connections available to your device into one glorious (and hopefully faster and more stable) stream of high-speed bandwidth. The project appears to take some of its cues from live video broadcasting companies like  LiveU , which sells custom made backpacks wired up with 3G/4G and Wi-Fi transceivers. These backpacks then spread the traffic load over whatever available networks it can connect to in order to maximize bandwidth, which is obviously a major plus if you're streaming live video. Dispatch, however, is planned as a software-only solution for the masses – no special backpack required. It will dynamically manage the traffic based on which networks provide the greatest bandwidth and have the clearest signal, which also means that even if one of the networks drops out entirely, you'll still have interne...
Post a Comment
Read more

New type of silicone exhibits both viscous and elastic properties

Looking for a more effective solution to the all-too-common wobbly table dilemma than a folded up bit of cardboard or piece of rubber under the leg, University of Virginia physicist Lou Bloomfield created a new type of silicone rubber called Vistik – it's malleable enough to take on any shape when pressed, but is still resilient enough to offer support, as it  gradually starts to return to its original shape as the pressure is released. The material could have many applications ... beyond just steadying up wobbly tables. Vistik is a viscoelastic material, meaning that it exhibits both viscous and elastic properties. As a result, when compared to something such as conventional silicone rubber, there’s a considerable time lag in its response to continuous pressure. “It seems elastic in response to sudden forces or impacts, denting in proportion to the sudden, brief stress and then returning almost instantly to its earlier shape when that stress is removed,” Prof. Bloomfield ex...
Post a Comment
Read more

Tricycle House pedal-powered RV offers lots of home comforts

The idea of living life on the road in an RV can be appealing. Unfortunately, most RV’s aren’t very environmentally friendly, nor are they self-sufficient. However, the Tricycle House isn’t like most RV’s, as it relies on pedal power to move between destinations, and boasts several pieces of clever folding furniture to provide those much-needed home comforts. Conceived by architectural firm People’s Industrial Design Office (PIDO) for 2012’s “Get It Louder” Exhibition in Beijing, the Tricycle House addresses the fact that private ownership of land is not permitted in China. The pedal-powered RV envisions a future in which individual Chinese people are able to more fully connect with their land, while living simply and sustainably, on their own terms. The Tardis-like house structure is affixed to a tricycle and constructed from polypropylene (a thermoplastic polymer). The polypropylene is cut with a CNC router, before being folded and welded into shape, retaining its strength but ga...
Post a Comment
Read more