Month: December 2015

A Softer Touch: Future Exoskeletons

Let’s all take a second to imagine what it would be like to fly around in Iron Man’s suit. To watch the bullets bounce off your amour and retaliate with a simple raising of your hand. It’s pretty cool, right? And no doubt a huge tactical advantage in almost any combat situation.

Unfortunately that exact image is firmly stuck in the world of superheroes right now, but it hasn’t stopped the human race from trying. Surprisingly, the idea of a human-enhancing exoskeleton isn’t that new, and the earliest attempt to develop one was as far back as the 1960s.

The first was known as “Hardiman”, the development of which was funded by the US office of naval research. This suit weighed a whopping 680 kg so  it wasn’t all that successful, as that weight would have probably done the exact opposite of any form of enhancement. But improvements were made, and a new design appeared in 2000 once the Defence Advanced Research Projects Agency (DARPA) began funding research of this nature.

The results involved a variety of high-tech metal leg braces, one of which evolved into one of the more well known examples. This was the Human Universal Load Carrier, which conveniently abbreviates to HULC to make it sound even more bad-ass. Despite an appropriate name this one didn’t work out too well either, with tests showing that users were more exhausted than enhanced. But they weren’t ready to give up just yet, and an updated version was tested again in 2011.

So how did this one work out? Third time’s the charm, right?! Wrong. While I’m sure there were some improvements, it seemed that the problem of hindering rather than helping was encountered yet again. We have a little more information on the problems this time, which included the users heart rate jumping by 26% and O2 consumption rising by 39%. Doesn’t seem like much of an enhancement to me.

Despite the many failures, the idea of the bulky, rigid exoskeleton still hasn’t died, with current US military research focussing on a new design known as the Tactical Assault Light Operator Suit (TALOS). The name alone gives an image of what they’re going for, relating to the metal giant from Greek mythology who effortlessly circled the island of Crete three times a day. While information is hard to come by, what I’ve read indicates a design similar to HULC.

But some scientists are skeptical that this heavy, rigid, hard-bodied design will ever succeed, claiming that it works against the natural biomechanics of the body. This would certainly explain the poor results obtained so far. If the users have to actively work against the exoskeleton in order to move, then all it becomes is an overly complex exercise machine. So how could the design change to overcome these problems?

That question is answered by some researchers at Harvard University, who are developing a softer alternative. Literally. The “Soft Exosuit” they are working on is made of fabric rather than metal, and is worn like a regular pair of trousers. This already prevents the suit hindering natural movement, and by using flexible cables and motors it can provide each step with an additional burst of energy.

This new technology has already proven promising in lab environments, with recent tests indicating that users were on average 7% more efficient while using the suit. The researchers also report that people feel they are walking slower and that footwear feels heavier once the exosuit is turned off. “People feel like they’re walking in mud” says Ignacio Galiana, an engineer working on the project.

Although results are promising the team are carefully avoiding unrealistic expectations, as the design is not without its problems. For example, the suit is currently programmed for walking, not running, and there are some flaws associated with movement over uneven terrain. They also mention that some people adapt better than others, so the benefits may not be consisted between users.

Nevertheless, this is a great first step along what appears to be the correct path this time, and the more comfortable design allows for some applications outside the military. This could be used to help people with disabilities regain the ability to walk to some degree, a service I’m sure many people would be grateful for.

So while we’re still a long way from the Iron Man suit, it seems we’ve found a more realistic alternative. Hopefully everyone will be able to own one these in the future. Superhuman race here we come!

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An Ocean of Problems

You can be sure, or at least hope, that the many effects of climate change will be addressed this week in Paris, and I’ve got my fingers crossed for some truly meaningful progress to be made. But there is one problem that many people remain startlingly unaware of; the effect that climate change is having on the world’s oceans.

At first glance that might not seem like much of a problem. I mean, what does the ocean do for us? Right? Well it turns out it actually does an awful lot for us humans, and all these services are at risk as the effects of rising temperatures mount up.

The ocean is actually an integral part of the climate system, taking up around 90% of excess energy in the form of heat. It still continues to take up heat to this day, and is an important factor in slowing the atmospheric warming we are so much more concerned about. This heat uptake causes the ocean water column to warm as well, and it is now detectable around the globe to depths greater than 2000m. This not only has a negative effect on ocean ecosystems, but weakens it’s ability to absorb heat in the future.

This is due to the phenomenon known as “Thermohaline Circulation”, meaning the circulation of both heat (thermo) and salt (haline) within the ocean. The mixing occurs due to differences in density, which is determined by both the temperature and salinity of the sea water. The colder and more saline the water, the greater the density. This means that colder water will sink, and will rise again as it travels the worlds ocean currents and warms.

What the increasing temperature of the oceans means is that, due to the fact that a certain volume of water can only absorb so much heat, any excess heat will be taken up by the less dense water being mixed downwards, causing the lower, colder areas of the ocean to warm. This will cause warming throughout the entire water column and the Thermohaline Circulation will become stabilised, as the increasing temperatures mean that density differences will be reduced.

This means that the mixing process will be slowed, maybe even stopped altogether if the warming continues, and the transportation of heat energy around the ocean will become much less efficient. This would make the ocean much less capable of absorbing heat from the atmosphere, as there would be fewer areas of water that are cold enough to absorb a meaningful amount. So where would that heat go now? Well… nowhere. It would remain the atmosphere above the ocean, and its warming would proceed at a much faster rate due to the loss of this regulatory system.

But ocean circulation would not be the only thing affected by the ocean warming. The intensity and frequency of extreme weather would also change, as well as the extent of the areas affected by them. Cyclones and extreme weather events pick up a lot of energy from the ocean in the form of heat. The air above the ocean’s surface contains a great deal of water vapour, and as this air rises and the vapour condenses, the heat absorbed during evaporation is released into the surrounding air. This causes an expansion of the air and a decrease in pressure, which then facilitates the rising of more air from the ocean’s surface. This process feeds more energy into the cyclone or weather system, increasing it’s intensity.

A warming ocean not only increases the amount of heat energy available to these weather events, but since the warming is occurring across the globe the energy exchange can occur over a much larger area. This means that previously unaffected areas of the world may have to rapidly adapted to dealing with these storms, and a poleward shift in the zones of maximum intensity has already been observed.

I hope you’re now thinking “Wow, this could actually really fuck things up”. Well there is more bad news to come my friends, as the ocean is not only getting warmer, it also is getting more acidic. The oceans also does us the service of removing some of our CO2 emissions from the atmosphere, and has absorbed around 28% of human-produced CO2 since the start of the industrial revolution. Doesn’t sound like much? Well it’s equal to approximately 150 billion tons of the stuff.

The trend in ocean acidification is now 30 times greater then the natural variation thanks to us, and the average surface ocean pH has dropped by 0.1 unit, which is a significant increase in acidity. While the large scale effects of acidification remain unknown, it is already clear that it is affecting marine wildlife.

Certain organisms rely on Calcium Carbonate (CaCO3) to form their skeletons or shells, and it is known that CaCO3 formation is disrupted if the environment is too acidic. This can also have indirect effects on other organisms, as some CaCO3 reliant structures, such as coral reefs, provide homes for many other forms of marine life.

It is also known to be slowing the release of sulphur from the ocean and into the atmosphere. This will directly increase the amount of atmospheric warming, as gaseous sulphur contributes to the reflection of solar radiation back into space.

But it has to end there, right?! There can’t possibly be more problems. Did you even read the title? There are many more. The last issue we’ll be discussing affects us more directly, as it has to do with our food supply. Fisheries currently generate $195 billion for the US every year, and fish is a key food source for many people worldwide. Fishing stocks have usually been quite predictable and reliable, as certain populations tend to stay in certain areas. But fish populations are beginning to move, flourish, or whither, depending on the species, due to the many effects we have already discussed.

It is estimated that around 70% of fish species are shifting their ranges, according to a major survey lead by ecologist Malin Pinsky of Rutgers University. This makes fish stocks much less predictable, and it can have surprising economic and political implications.

Over the past decade, huge amounts of Mackerel began appearing of the coast of Iceland, indicating that the populations were moving further north. Iceland took advantage of this during a financial crisis in 2009, and increased the amount of Mackerel they were catching. This was not taken well by competing fleets in the EU and Norway, who had rights to the majority of the catch, claiming that Iceland’s increased Mackerel haul was affecting their own stocks.

This prompted quite a fierce debate on the science of monitoring fish populations. Parties disagreed on the size of the whole population, whether competing fleets were even catching from the same population, and even what waters should be included in the Mackerel’s range.

Luckily, it would appear that this “Mackerel War” has come to a close, with new fishing quotas being agreed on by all parties involved. But it remains a very real example of how the changing environment of the ocean can affect the world of us landlubbers.

I hope that by now you have a good idea of the problems the ocean is facing, but I’d like to point out that there is much I didn’t mention to make this post a reasonable length. Given the prominent role of the ocean in the climate system I’m surprised we haven’t heard about this in the past, and I encourage you to go and find out more. Our ignorance of what’s going on in the ocean is what allowed things to get this bad, and once we’ve educated ourselves we need to start setting up efforts to better understand and counteract these problems.

Let’s hope this at least gets mentioned in Paris, and that someone there decides that enough is enough.

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