Posts Tagged‘test’

The Intriguing Science Behind Bouncing Dead Batteries.

Everyone can relate to the frustration of having a drawer full of batteries that are in an unknown state of charge. For most people the only method they have to deduce whether they’re good or not is to try them out in a device, something that inevitably leads to frustration when your spares show up dead as well. The inclusion of battery testers on the batteries themselves (or in the packaging) seemed like a great idea however it never seemed to catch on presumably due to cost factors. Whilst geeks like myself might have a voltmeter handy to get accurate readings in an instant they’re not a ubiquitous device and an effective way of testing batteries still eludes most.

That is until they see this video:

Honestly when I saw this video I was pretty sceptical as the video, whilst highly informative, is anything but scientific. Instead of having 2 batteries from the same brand (and preferably from the same batch) for comparison the effect could be explained by differences in manufacturing between the two. I didn’t take the opportunity to test it myself however, even though I do have a drawer full of batteries that are all in unknown states, but after seeing this video parroted around various life hacking sites I figured that if it was total bunk someone would’ve called shenanigans. It seems that the video is accurate and the science behind why empty batteries bounce is very interesting.

It’s not, as many have speculated, related to a reduction in weight between a full battery and a discharged one. Batteries like this are a closed system, chemically speaking, so save for a few milligrams here and there due to handling or (more catastrophically) a breach in them batteries don’t change their weight. Instead it’s a quirk of the manufacturing process and the change in densities of the various materials inside the battery, all of which result in it becoming bouncy.

In a typical alkaline battery the chemical reaction that takes place to produce charge also results in the materials shrinking. The reason for this is that as the battery discharges oxygen molecules from the cathode (negative ) manganese oxide terminal migrate to the anode (positive) zinc anode, producing zinc oxide. When this occurs the total volume decreases as the oxygen atoms are able to pack themselves much tighter on the zinc oxide terminal than they can on the manganese oxide. This results in the internals shrinking somewhat and, as a consequence, tugs on the side of the pressure seal on the bottom of the battery. This causes it to bow outwards providing a spring like structure which results in the bounce when dropped.

Now I haven’t looked at a lot of batteries recently but I can image that some other designs might make this trick fail due to the design of the cathode terminal. This also means that the trick is probably unique to the cylinder style batteries (A, C, D, etc.) as whilst other types of batteries have similar chemical reactions their construction is vastly different. So I wouldn’t recommend dropping your car or latern batteries to try and test them out, lest you want to spend some time in the chemical burn ward and paying for a large chemical spill.

Can We Drop This Whole Left/Right Brain Business Already?

I’m something of an armchair neuroscience minor as I often find myself researching behavioral traits, influences and motivations simply for the heck of it. I think its partly because I have this need to understand why people act the ways they do at a fundamental rather than practical level thanks to my many years spent as an extreme introvert during my high school years. It also hooks into the skeptical side of me quite well as I’ll often find bits of pop psychology that get bandied around by my not-as-interested friends that I’ll attempt to correct, lest they spread that nonsense to other people.

It seems that some ideas are just too sexy to go away, however.

I was watching TV recently, a veritable treasure trove of techniques based on modelling the human psyche, when an ad for a car popped up. Now I can’t remember exactly which car it was and a quick Google brought up two current campaigns that play on the same idea. The first one is a series of print ads from Mercedes-Benz and the second (and the one that seems the most familiar) is one from Kia:

They both play on that whole left brain/right brain idea where by the left side is some kind of cold calculating logic driven engine whilst the right side is the creative one, filled with random ideas and that spark that all creative people seek. This then lead onto the ideas that men are typically left side dominant and women are right side dominant. However there also seemed to be a bevy of online tests available to check if you were left or right side dominant, seeing if you’re more of a creative than logical kind of person. For years it seemed everyone was drinking this kool aid, seemingly without any consideration to how the brain actually works.

It is true that there are functions of the brain that appear to be dedicated to particular hemispheres, which is referred to as the lateralization of brain function, it can also be shown that both sides of the brain are quite capable of performing those functions and indeed do so in many cases. There’s also no guarantees as to which functions are lateralized where as different people will have different hemispheres dominant for a particular function. Short of removing one half of the brain no person can be truly left or right brain dominant in the sense of being creative or logical. Indeed the research shows that both logical and creative functions are present in both hemispheres completely debunking this whole idea.

What was even more preposterous were the online tests devised to determine whether you were right or left brain dominant. The most famous of which, one which spurred a rather heated discussion between me and my friends at the time, was the spinning dancer. Looking at the image you’ll see the dancer spinning either clockwise or counter clockwise and that was somehow meant to tell which part of your brain was dominant. Funnily enough I could see it spin both ways and could make it change on demand by looking at the feet and the shadow so I wasn’t entirely convinced that it was a proper test for a phenomenon I already didn’t believe in. Indeed it is simply just an optical illusion with your brain “filling in” details that it perceives as missing and such activities are carried out by the visual cortex which spans both hemispheres.

The fact that we’re still seeing things referencing this whole fake phenomena means that it’s still widely believed to be true, which is really unfortunate. Whether a person is more creative or logical has nothing to do with which part of their brain is dominant and is in fact more likely due to the nurturing of the innate creative/logical talent that we all have. I guess any simple metric that divides people into two groups will always be popular (“Oh you shouldn’t listen to him, he’s such a left brain!”). It’s a shame really but hopefully like any fad it’ll eventually fade away, never to be mentioned again.

Copenhagen Suborbitals: Changing The Space Access Game.

Getting off the rock which we’re gravitationally bound to is an expensive endeavor, so much so that doing it has well been out of the reach of anyone but the super-governments of the world for almost half a century. We’re in the middle of a space revolution with private companies popping up everywhere promising to reduce the cost of access to space with many of them delivering on their promises. Still even with so many revolutions happening in the private space industry the cost of doing so is still well out of the reach of the vast majority of people in the world, even though they’ve come down by an order of magnitude in the past decade.

Still there are people working on extremely novel solutions to this problem and they’re starting to show some very promising results. Late last year I wrote about Copenhagen Suborbitals a volunteer team that is working on a single person rocket using only donated funds. Back then they were gearing up to launch their first test rocket called HEAT from their sea launch platform that was propelled by a submarine that one of its creators built. Unfortunately they did not manage to launch as the cryogenic valve for the liquefied oxygen had frozen shut (thanks to the hair dryer they used as a heater draining the batteries on the sub) preventing the rocket from igniting. They were determined to launch it however and just recently they gave it another attempt.

The upgraded rocket, dubbed HEAT-1X, has a few improvements over its previous incarnation. The sea launch platform is now a fully enclosed unit, no longer requiring external propulsion from a submarine to get it into position. HEAT-1X now uses a polyurethane rubber mix instead of the previously used paraffin wax which was found to not vaporize completely which caused a reduction in the resulting amount of thrust. With these improvements in mind they attempted launching again back on the 3rd of June, and the results speak for themselves:

The launch, whilst undoubtedly a success for all involved, wasn’t without its share of problems. HEAT-1X did manage to achieve supersonic speed however it deviated from its direct vertical flight path considerably. Even though they were out in the ocean mission control decided to shut down the engine after 21 seconds of flight. The craft still managed to achieve a height of approximately 2.8KM in that time and covered over 8KM in ground distance. There was successful separation of the booster and craft stages however the parachute on the booster was torn free due to the high drag it experienced. The space craft’s parachutes didn’t unfurl properly either causing it to receive significant damage upon landing. Unfortunately the booster was lost to the Baltic Sea but the capsule was recovered successfully.

Despite those problems the HEAT-1X flight represents a tremendous step forward for the Copenhagen Suborbitals team and shows that they are quite capable of building a craft capable of delivering people into suborbital space. They’re still a long way from putting a person in one of their crafts (3~5 years is their estimate) but this launch validates much of the work they have done to this point. I really can’t wait to see them achieve their vision of getting someone into space on a shoestring budget and should they succeed they will make Denmark the fourth nation ever to launch a man into space (Russia, USA and China were ahead of them, if you were wondering). Considering that it will all be done with volunteer time and donations make the achievement even more incredible and I’m sure they’re inspiring many of their younger Danes to pursue a life in the sciences and engineering.

Could Skylon Be The First Single Stage to Orbit Craft?

The current way of accessing space isn’t sustainable if we want to make it as a space fairing species. Whilst the methods we use today are proven and extremely reliable they are amongst the most inefficient ways of lifting payload into orbit around our planet, requiring craft that are orders of magnitude larger than the precious cargo they carry. Unfortunately the alternatives haven’t been too forthcoming, due in part to nuclear technologies being extremely taboo and the others still being highly theoretical. Still even highly theoretical ideas can have a lot of merit especially if they have smaller aspects that can be tested and verified independently, giving the overall theory some legs to stand on.

I’ve talked before about the idea of creating a craft that uses only a single stage to orbit (SSTO), in essence a craft that has only one complete stage and conceivably makes extensive use of traditional aerodynamic principles to do away with a lot of the weight that conventional rockets have. My proposal relied on two tested technologies, the scramjet and aerospike engine, that would form the basis of a craft that would be the Model T equivalent for space travel; in essence opening up space access to anyone who wanted it. In all honesty such a craft seeing reality is a long way off but that doesn’t mean people aren’t investigating the idea of building a SSTO craft using different technologies.

One such company is Reaction Engines, a name that I was only marginally familiar with before. They’ve got a proposal for a SSTO craft called Skylon that uses a very interesting engine design that combines both an air breathing jet engine as well as a traditional rocket motors. The design recently passed its first technical review with flying colours and could see prototypes built within the decade:

They want the next phase of development to include a ground demonstration of its key innovation – its Sabre engine.

This power unit is designed to breathe oxygen from the air in the early phases of flight – just like jet engines – before switching to full rocket mode as the Skylon vehicle climbs out of the atmosphere.

It is the spaceplane’s “single-stage-to-orbit” operation and its re-usability that makes Skylon such an enticing prospect and one that could substantially reduce the cost of space activity, say its proponents.

The engine they’re proposing, called Sabre, has an extremely interesting design. At lower speeds it functions much like a normal jet engine however as speeds approach Mach 5, the point at which my hand waving design would switch to a scramjet, it continues to operate in much the same fashion. They do however employ a very exotic cooling system so that the engine doesn’t melt in the 1000+ degree heat that would be blasting the components and once Skylon is out of the atmosphere it switches to a normal rocket engine to finish off the job.

The issues I see, that face nearly all SSTO designs, is the rule of 6 for getting to orbit. The rule simply states that at Mach 6 at 60,000 feet you have approximately 6% of the total energy required to make it successfully to orbit. Skylon’s engines operate in the jet mode all the way up to Mach 5 to an altitude of 85,000 feet which is no small feet in itself, but it’s still a far cry from the total energy required. It is true though that the first stages of any rocket are the most inefficient and eliminating them by using the atmosphere for both oxidiser and thrust could prove to be a real boon for delivering payloads into orbit. Still whether this will be practical with Skylon and the Sabre engine remains to be seen but there are tests scheduled for the not too distant future.

Walking through unknown territory like this is always fraught with unknowns so it’s no wonder that the team at Reaction Engines has been met with such skepticism over their idea. Personally I’m still on the fence as their technology stack is still mostly unproven but I applaud their vision for wanting to build the first SSTO craft. I’d love to see the Skylon making trips to the International Space Station, effectively replacing the shuttle and extending the ISS’ lifetime but until we see some more proof that their concept works I’m going to be skeptical, but it won’t take much to make into a believer 😉

SpaceX’s Falcon 9 Creates Orbital Dragon and History Once Again.

6 months ago I wrote about SpaceX’s historic flight of their Falcon 9 rocket and how much it meant to us space romantics. Their tentative schedule had me all aflutter with the possibility of seeing not one, but two more flights of their flagship rocket within this year. It was looking entirely possible too as just on a month later they were already building the next rocket and there was even a hint that I might get to see it take off on my trip through America. Whilst I may not have gotten to see the launch for myself SpaceX is not one to disappoint with them launching their second Falcon 9 rocket earlier this morning carrying a fully fledged version of their crew and cargo capsule, the Dragon.

The launch itself didn’t go by without a hitch though with some bad telemetry data causing the initial launch to be scrubbed and rescheduled for about an hour later. However once they were past that minor hurdle they were able to continue with launch preparations and launch without incident. This is testament to their ability to rapidly troubleshoot and resolve problems that would likely cost anyone else at least a day to recover from. Elon Musk is definitely onto something when he thought about running a launcher company as a startup, rather than a traditional organisation.

The mission profile was a relatively simple one although it represents a giant leap forward in capability for SpaceX. The previous launch of the Falcon 9 carried with it a Dragon Spacecraft Qualification Unit, basically just a shell of a full Dragon capsule designed to be little more than a weight on top of the Falcon 9 rocket. That capsule lacked the ability to separate from the second stage of the Falcon 9 it was attached to and was also designed to burn up on re-entry. The payload for this mission however was a fully functional Dragon capsule with the full suite of avionics, support systems and the ability to return to earth from orbit. It was also carrying a small fleet of government owned CubeSats that were launched shortly after they achieved orbit. Approximately 3 hours after the Falcon 9’s launch the Dragon capsule returned safely to earth, splashing down in the Pacific Ocean.

I, along with every other space nut out there, are incredibly excited about what this means for the future of space. Not only has SpaceX managed to successfully launch a brand new rocket twice in 6 months they’ve done so with an almost flawless record. The pace at which they’re progressing is really quite astonishing considering how small they are compared to those who’ve achieved the same goals previously. The team that Elon Musk has assembled really deserves all the credit that they get and I now I wait with baited breath at their next launch as that will be the first private spacecraft ever to visit the International Space Station.

It’s really quite exciting to see progress like this in an area that was once considered only accessible by the world’s superpower governments. Whilst we’re still a long, long way from such technology becoming an everyday part of our lives like commercial air travel has the progress that SpaceX has made shows that the current cost to orbit can and will come down over time. This also gives NASA the opportunity to stop focusing on the more rudimentary aspects of flight that SpaceX is now capable of handling, leaving them to return to what they were once known best for: pushing the envelope of what the human race is capable of in space. So whilst we won’t be seeing another Falcon 9 launch this year as I had hoped all those months ago this perfect flight of the first fully functional Dragon capsule signals that the future of space travel for us humans is not just bright, it’s positively blinding.

SpaceShipTwo, Flying Solo.

I’ll be the first to admit that I have a massive nerd crush on any private space company that’s demonstrated working hardware. Long time readers of this blog will know that there are two in particular: Virgin Galactic and SpaceX. Most recently all of my love has been directed to SpaceX as they began to make waves with their Falcon 1 and 9 rockets but it’s been a while since we heard anything about Virgin Galactic’s craft, SpaceShipTwo. Three months ago saw them flying a full crew aboard both the VSS Enterprise and Mothership Eve so we knew they were in the thick of testing and verifying all of their flight systems. Still even the extremely head of Virgin Galactic, Richard Branson, hadn’t made any statements about the progress of the craft.

That was until just recently, however.

Flicking through my Twitter feed this morning I noticed quite a few articles popping up mentioning SpaceShipTwo. As it turns out the sub-orbital craft made its first solo flight after be released from it’s mothership at 45,000 feet and gliding back down to earth:

“This was one of the most exciting days in the whole history of Virgin,” said Richard Branson, founder of Virgin Galactic. “For the first time since we seriously began the project in 2004, I watched the world’s first manned commercial spaceship landing on the runway at Mojave Air and Space Port and it was a great moment. Now, the sky is no longer the limit and we will begin the process of pushing beyond to the final frontier of space itself over the next year.”

“This is a critical milestone in Virgin Galactic’s test program and a great day for the commercial spaceflight industry,” added John Gedmark, Executive Director of the Commercial Spaceflight Federation. “At the end of the day, getting hardware off the ground is what it’s really all about. Today’s SpaceShipTwo test flight marks another key milestone towards opening the space frontier for private individuals, researchers, and explorers. Congratulations to the entire SpaceShipTwo team.”

Virgin Galactic has since released a video of the flight in question:

The news comes hot on the heels of an announcement made just a couple weeks ago that Virgin Galactic will be open for business in just 18 months. Between now and then there are still a myriad of tests and certifications that need to be done on the craft, not least of which is several powered flights to the edge of space. This first drop test verifies SpaceShipTwo’s glider mode of operation and is a crucial first step towards the ultimate goal of powered flight. The next 18 months will see a steady progression tests to push the envelope of SpaceShipTwo’s capabilities ensuring that this iconic spacecraft is never too far from public eye.

To me SpaceShipTwo represents exactly where the private space industry needs to be heading. Branson’s focus on commoditising travel to space ensures that, whilst sub-orbital junkets are out of the reach of the everyman today, one day they will be as international air travel was decades ago. Virgin Galactic is also committed to furthering their capabilities beyond sub-orbital flights with Branson stating on several occasions that should SpaceShipTwo be a success (and by all means, it already is) that the next generation of craft will be capable of orbital flight. You could take that as just marketing hype but when the man behind SpaceShipOne already has designs for such a craft it would seem doubtful that it was mere rhetoric.

Humanity is on the cusp of a revolution in space where venturing to the final frontier will be as common as visiting another country. As someone who can’t stop dreaming about seeing the blue marble for themselves the idea of anyone with the will and the want to venture beyond our atmosphere being able to do so brings me unimaginable joy. The next decade will see amazing revolutions in the private space travel industry and I, for one, can’t wait.

The Science of the Human Condition.

I’m not usually one to newsbot¹ but this article got me thinking in a direction that I wanted to share:

People with strong religious beliefs appear to want doctors to do everything they can to keep them alive as death approaches, a US study suggests.

Researchers followed 345 patients with terminal cancer up until their deaths.

Those who regularly prayed were more than three times more likely to receive intensive life-prolonging care than those who relied least on religion.

The team’s report was published in the Journal of the American Medical Association.

It suggests that such care, including resuscitation, may make death more uncomfortable.

Just over 30% of those asked agreed with the statement that religion was “the most important thing that keeps you going”.

Let it be known first that I like religion, it does a lot of good things for otherwise lost and direction-less people. It is very interesting to note this funny little bit of science and it does give rise to some interesting philosophical points.

It would seem that believers in religion would at the time of their deaths be more comfortable with the idea of passing onto the next plane of existence. Since they are guaranteed by their faith that there is something waiting for them on the other side that should put their mind at ease.

Or does it?

The time leading up to your death really becomes the ultimate test of your faith. You start thinking about your legacy, how you led your life and what will become of the world when you depart it. Then if that isn’t enough you will then start to think about whether or not you’ve lived your life close enough to the rules that were set out by your religion, and more likely then not all the things you’ve done wrong in that time. Needless to say this would lead to desperation more then acceptance, since you would want more time to reconcile your faults before passing on and receiving your final judgement.

Atheists on the other hand believe that there is nothing after death just as there was nothing for them before birth. If you’re truly in touch with that kind of belief (Atheists have faith to you know) then you know there’s nothing you can do to change it. Although I would postulate that before  the point of no return, I.E. before the doctors have tried everything to save you and haven’t said “x days/hours to live”, they would behave much the same as the religious attempting every possible avenue to extend their mortal existence.

It may just be that the religious have more reason to continue living, since they have more work to do before they pass on.

After reading some discussion on this topic someone posted a quote that I’ve believed in most of my life, ever since I left Christianity as my religion:

“Live a good life. If there are gods and they are just, then they will not care how devout you have been, but will welcome you based on the virtues you have lived by. If there are gods, but unjust, then you should not want to worship them. If there are no gods, then you will be gone, but will have lived a noble life that will live on in the memories of your loved ones.” – Marcus Aurelius

It is interesting to note however the one flaw in this line of thinking. That the Gods and us share a similar line of thought, and our definitions of just and unjust are similar. Therefore, we can only assume (take in faith) that should the Gods be just and you live a good life that Marcus is correct.

¹Since I can’t find a definition for this word, I shall coin it now. Newsbot, when used as a noun, refers to a person/blog/entity that takes a story directly from the news and then takes some or all of the content and posts it on their site/medium with a small amount of additional detail, usually an opinion or drivel. When used as an adjective it refers to the process of hunting down news to regurgitate somewhere else in order to appear that you’re actually producing content, when really you’re just repeating someone else’s hard work and trying to add a bit of flavour. If you can’t guess already I think people who produce newsbot blogs don’t add any value, but that’s another post for another day 😉