Toothbrush saves the space station

The headline is probably overwrought, but essentially astronauts on the International Space Station needed to replace a power unit on the exterior of the space station.  They tried to complete this replacement a week ago, but were foiled by metal shavings in a bolt hole that made it impossible to drive a bolt.  So after eight hours in space, the astronauts returned to the space station to come up with a way to overcome the problem.  The main catch being that they couldn’t run down to Home Depot to pick up some parts – they had to make do with what was on-board.  In a scene that I like to imagine was exactly like the one from the movie Apollo 13, the international space station astronauts along with engineers, technicians, scientists, and assorted- interested parties on the ground came up with a solution.

There are a couple of things I like about this.  First is the teamwork and communication involved that got the problem fixed.  Secondly, like I have mentioned about keeping good records, everyone know exactly what was on the space station.  They were then able to figure out how to use those items in not-intended manners to fix the problem.  With these tools, smart and motivated people were able to solve the problem.  From reading the articles, I don’t think that the toothbrush actually saved space station – from what I can tell they used it to clean the metal shavings out of the bolt hole – but the troubleshooting was impressive.

As an engineer, I need to remember to keep this open mindset when I approach new problems and non-working issues.  Maybe I can use a tool in a different way than I am using it now to overcome my obstacle an move on.  It seems that the space program is providing quite a bit of food for thought over the the past few months.  I hope it continues.

Data is necessary to solve problems

I recently read an article that got me thinking.  In a nutshell, part way through their 1970s/1980s mission out of the solar system, the Pioneer spacecraft started moving slower than they should.  No one could figure out why this was.  At first, it was surmised that engine fuel was leaking out.  This was ruled out as the slow speed continued for months.  No one could figure out why the spacecraft was moving slower than it should.  The problem was taken up again, 10 years after Pioneer 10 was lost to NASA.  The new theory is that the heat given off from the thermoelectric units “pushes” against the spacecraft, thereby retarding the forward motion.  This is all well and good, but in the article, there was one point that was amazing/confounding to me.

VG: Why has it taken so long to reach this point?
ST: Lack of proper data storage was a huge problem. In the 1970s and 1980s, mission data was recorded on magnetic tapes, and to study the Pioneer anomaly we needed the probe’s navigational data. But mission tapes were normally saved for only a few months and then thrown away, so you’re lucky if you can find what you need. The only data available from Pioneer 10 was from planetary flybys, which were kept to study gravity around planets. Then we had to figure out how to read it. You need a proper machine with the right software, and you need to “upconvert” the data to modern formats so it can be used in today’s computer modeling systems. That took years.

So the NASA threw away most of its data and stored what it did keep in almost-unusable formats?!?!  This is a problem for engineering at all levels:  hobby, inventor, consumer, industrial, etc.  Basically when a problem or a “Huh?” arise, the only way to find a solution is to have reliable data.  Sometimes that data is extremely hard to come by, if not impossible.  I know I’ve participated in some designs that I would be hard-pressed to recreate the design environment and/or the exact parameters of use.  It’s a shame that information has been lost, but it would be even more of a shame if I were forced to fix something because 10 years down the road something isn’t working right.  I am glad NASA figured out their problem – in doing so they have given me some food for thought.

Pioneer Family

New Mars rover, Curiosity, a study in great robot design

In the past I’ve highlighted some of the current Mars Rover’s accomplishments.  It is crazy to think that the Opportunity has been roving the surface of Mars for eight years sending back great images and performing path-breaking exploration.  But, there are greater things on the horizon:  the Curiosity.

mars4.jpg

There are several mind-boggling things about the robot, but I am going to touch on four that seem really impressive:  nuclear power, size, landing method, and instrumentation.  When coupled with a space flight and foreign planet exploration, this robot sets the standard.

  • Nuclear Power:  This is the big one.  The Curiosity uses the heat from a lump of decaying plutonium to generate electricity (I wonder if they are using TEMs for this – we’ve done some work with them and their inefficiencies have always stymied a robust design) to run the robot.  This solves the problem of solar panels getting dirty, operation at night, and weak sun energy on Mars.  I don’t think this is a viable method for the home-robot market, but I am really impressed by this.
  • Size:  This thing is a monster.    It is about the size of a Mini Cooper!  That’s about 15 feet long.  The largeness of the robot is another reason for the nuclear power source:  it simply needs more oomph than a solar-based solution can provide.  With a size like that it will be able to cover large distances in its target zone:  the Gale Crater.
  • Landing Method:  This might be the craziest thing of all.  Basically the capsule containing the Curiosity enters the Martian atmosphere, slows down, and then deploys a parachute.  After it slows, it jettisons the heat shield to expose the rover to the planet.  Rockets then fire, allowing the capsule to hover, then cables extend to the planet surface and the rover is lowered to the ground.  If that is not enough, the capsule then fires up the rockets again and shoots itself far away from the Curiosity so that it won’t damage the rover on impact.  There seems to be a huge amount of things that can go wrong with this approach, but they needed something that the inflatable ball landing approach, because the robot is so large.  I can barely get my mind around the complexities of this landing approach.
  • Instrumentation:  The robot is equipped with an HDTV camera; various sensing, masking, and filtering capabilities so the robot can “see” in different spectra; a laser that can vaporize rock – the rover then can analyze the vapor; an x-ray spectrometer; and a 7-foot robot arm to list just a few.  All of the instrumentation is on-board to help determine if the life or its precursors ever existed on Mars.

Basically, this rover is taking a gun to a knife fight.  There are a bunch of things that can go wrong on the way there, but if the Curiosity lands safely on the surface of Mars, I expect a bunch of great science to to performed.

A Soft Jumping Robot

soft_robot_jumping

Japanese researchers have created prototypes for “soft” robots that can jump, crawl,  and roll (even uphill).  A detailed summary of their work can be seen in this pdf file.  The prototype uses Shape Memory Alloys, or SMAs, by Toki Corporation.  By applying a pulse-width modulated signal the alloy is heated and deforms to a predefined shape.  Multiple SMAs allow the overall circular form of the robot to be deformed allowing rolling and jumping shapes to be created.  A more 3-dimensional version, where multiple circles are used to create a spheroid shape, can also crawl.

Most mobile robots use wheels or legs to create ground locomotion, so this concept is a unique departure from those ideas.  Like a lot of research ideas the actual practical applications are limited.  Currently SMA are not very energy efficient and have quite a bit of hysteresis in their pre-formed shape.  This means your power supply (batteries) and controller may not be able to reside on the mobile shape and that the shapes you form may have a lot of variability.

But imagine thousands of miniature strips of SMAs each receiving tiny currents from a central controller and you’ve pretty much modeled a human joint.    You can also imagine how useful robots based on this technology could be in places where energy is readily available and gravity is not a force to be reckoned with.  Satellite technology and space exploration might benefit from the ideas proposed by these researchers.

End of an era

Here is a moving pictorial essay of the now-mothballed space shuttle fleet.  Although the original promise (frequent, low-cost flights to space for both the government and private  entities) of the space shuttle program never played out in reality, the shuttle itself always inspired me.  I am fully on-board with the new space initiatives that bring private funding, know-how, and excitement to space-travel and exploration, but the shuttle has a warm spot in my heart.  I am too young to have been caught up in the race to the moon.  I came of age with the promise and heartache of the shuttle.  It seems odd to me that the program has now ended.  I hope that it won’t take too long for regular manned flight to space to resume again. . . although I don’t think it will come from NASA.

Assorted Links and Housecleaning

  • A while back I mentioned a size comparison for the solar system.  Here is a neat utility that goes from the super small (strings) to super large (estimated universe), with a bunch of cool references (T-Rex, all people stacked on top of each other, etc.).  The really cool thing is that it was created by a seventh grader!
  • After a slight delay,  the SpaceX rocket launched and is real close to docking with the International Space Station.  I’m glad my initial excitement has been rewarded.  Robots unite!

  • In addition, the Mars Rover is back fired up and running.  It is already sending back cool pictures of Mars.  I dig how this picture of the horizon, also has a “self-portrait” of the rover’s shadow.  Robots unite!

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Two cool space-related news items

I have a passing interest in space and space exploration (just how passing will soon become apparent) and I like to share the wonder of space when I see something cool.  Two events just came to my attention that I think are worth mentioning.

  • First, this Saturday, a privately funded rocket will launch from Cape Canaveral and dock with the International Space Station for a resupply mission.  It will be a robot-controlled/automated flight (so no private astronauts. . . . yet).  There a few things about this that I like.  First that it is privately funded and the company is specifically aiming to get private astronauts/space-tourists into space.  The other thing that is neat is the automated aspect of the flight.  While automation has always been a part of space exploration, once I start thinking about how embedded and advanced the automation is, it blows my mind.

  • The second neat thing, is something that had fallen completely off my radar:  the Mars Rover.  It is just now coming out of its fifth Martian winter (eight Earth years) and now is back to exploring.  It will now add to the 21.4 miles of territory it has thus far explored.  This is an ultimate robot.  It is solar powered, remote controlled, and controlled with an embedded system.  It boggles my mind that it only was supposed to be a three month mission and it is still operating eight years later.  This is especially true, when it was necessary to re-format its memory and upload a new program to solve a memory-conflict problem. . .  from 150,000,000km away.  I love it when a plan comes together.

  • Bonus Item – Don’t forget that this Sunday at 6:23pm PST there is a solar eclipse that can be viewed on the West Coast.

Asteroid Mining with Robots – an interview

A few weeks ago the web was all aflame because of the plans of some extremely rich folks to mine an asteroid for platinum and platinum-like minerals.

Here is a neat interview with an MIT scientist (Sara Seager)  that has signed onto the venture talking about some of the technical aspects of the project.   There are a couple of salient points that she makes in the interview that I think are worth mentioning.

  • The mining will have to be done by robots.  In addition, the robot technology is essentially there right now to do it.  That is because mineral and oil extraction is currently taking place at the bottom of the sea, which is a close parallel to space in regards to environment, ruggedness, etc.
  • There are two ways to mine the asteroid:  send robots to the rock, mine the rock, and return.  OR, send robots to the rock, lasso the rock, tow it to a lunar orbit, and then different robots to the rock to mine it.  From a purely gut-level reflex, I prefer the former alternative.  No sense in bringing an extinction-level event closer to earth.

High Art

docking_atv3_ISS

Great photo from the International Space Station of the robotic cargo vehicle ATV-3 docking.

NASA’s page.

It’s always the small stuff. . .

Six months ago, the physics world was aflame with news that neutrinos may travel faster than the speed of light!  If true, the results would overturn a century of theoretical physics and dramatically shift our understanding of the universe.  Plus, humans might be able to travel to a galaxy far far away.  Alas, it appears that the error was introduced by . . .  loose cables?!?!  Improperly tightened cables introduced a 60ns delay into the timing measurements, which would account for the vast majority of the observed “time shift”.  Anyone that has ever debugged something on the bench can relate:  a intermittent power connection; a cold solder joint; or a hairline fracture can cause nonsensical results that can waste hours and days.

So our understanding of how the universe works is back on solid ground, due to diligent engineering and the operation of the scientific method.  BUT. . . there is more to the story.  During the exploration that uncovered the loose cable issue, another small error that would shift the results back into the sci-fi realm was discovered.  Science never sleeps, and the bench-top gremlins are never defeated, only pushed back for a while.  I can’t wait to see the next chapter in this fascinating story.