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MILLIONS OF YEARS of evolution have enabled human beings to develop a smooth, energy-efficient way of walking.
But, biomechanical engineers suggested on Wednesday, there’s always room for improvement.
They unveiled an unpowered exoskeleton – a small, light, spring-activated device that fits on the lower leg and reduces the energy cost of walking by around 7%.
“The difference might seem small, but it makes a significant difference for humans,” said Steve Collins of Carnegie Mellon University in Pittsburgh, Pennsylvania.
It’s the rough equivalent of an infantryman being able to march 7% more in terms of time and distance for the same energy expenditure, or a trekker freed of the energy cost of toting a four-kilo (10-pound) backpack, he said.
Exoskeletons – externally-worn devices intended to augment physical actions or strength – have a long history.
Back in the late 19th century, pioneering inventors toyed with coiled springs tucked into the heels of cowboy boots, or harnesses with rubber bands that were attached to the legs and sought to make walking easier.
But the weight and design of the gadgets were often an energy drain in themselves.
Partly as a result of such setbacks, exoskeleton design today favours powered devices, but in turn has to struggle with challenges such as battery range and bulk.
The new gadget, described in the science journal Nature, is a carbon-fibre mechanical device weighing about 500 grammes (1.1 pounds) for each leg.
It comprises a spring that is attached at one end to a strap around the top of the calf, and, at the other end, to the heel of the shoe.
When the heel meets the ground, the spring becomes extended, and a tiny mechanical clutch engages to ensure that the spring briefly retains this energy.
When the heel is lifted, the clutch disengages and the spring is released, thus giving up its stored energy and providing discreet help for the calf muscles as they lift the lower leg.
There’s no motor, no battery and no computer, the inventors said proudly.
“The unpowered exoskeleton is like a catapult,” said Collins’ team-mate, Gregory Sawicki of North Carolina State University.
“It has a spring that mimics the action of your Achilles’ tendon, and works in parallel with your calf muscles to reduce the load placed upon them.”
The prototype was developed through tests on nine able-bodied volunteers, who wore an exoskeleton on both calves.
They were placed on a treadmill and filmed in order to find a spring whose tension offered the best savings in energy cost.
The reduction averages 7.2%, plus or or minus 2.6%, for healthy adults who used it under natural conditions wearing normal athletic shoes. The performance is comparable to savings with powered exoskeletons, according to the paper.
The device has been patented, and the hope is that it can be adapted for people with reduced mobility as a result of injury, stroke or ageing.
Further research is needed to ensure that long-term use of the device does not have an impact on body mechanics elsewhere, Collins said in an email exchange.
“The body is very complex, and it is difficult to predict such effects,” he said.
Walking takes up a big chunk of our daily energy use.
“People expend more energy during walking than any other activity of daily life,” said the study.
“We take about 10,000 steps per day, or hundreds of millions of steps in a lifetime.”
- © AFP 2015.
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The issue isn’t politics, it’s party politics.
@John Latham: how so, was the last appointment not labour?
@Shawn O’Ceallaghan: the issue is not whether any particular appointment was or wasn’t party political. This is about designing a system that resists subversion by party political forces.
Putting political judging aside on certain cases there is a much more serious issue when it comes to sentencing. Is someone breaks into a judges or tds (regardless of party) home they will end up with a 5 year jail sentence. Is someone breaks into another persons home, beats them within an inch of their life leaving them in a coma for 10 years the sentence will be suspended or 5 months tops. That’s the REAL issue.
Excellent, thoughtfulness vigorously analytical argument.
I cavil on one point. The Executive is theoretically accointable to the Oireachtas but in practice it is the Oireachtas which is controlled by the Government, the executive branch.
I agree that Judges are influenced by values, political outlook, ideology and even biases, sometimes unconsciously held. Some judges transcend that.
There are major problems in Ireland. Access to the law is a major problem. It is often unaffordable to vindicate legitimate rights.
Law and the judicial system ultimate favour wealth and privilege. Judges are socially programmed to protect private property rights and to relegate social and public policy considerations as secondary to the supremacy of private property rights. There have been limited exceptions to this.
Great article. Realistic and without a particular crow to pick. It informs the debate.
@Tony Daly: can u speak English and cut out the dramatic words
@Tony Daly:
It’s not the privileged with 115 + convictions and still walking the streets though is it.
Yes they may favour, in some instances people of certain social classes. However, they at the same time hand down ridiculously lenient sentences for s*******s who terrorise their neighbourhood.
Rape sentences are so lenient some can even walk out of court the very same day!
But fail to pay tax on garlic, merits 7 years.
“No judge is pure”
Never a truer word spoken
@jon-boy55: I’d settle for competent these days…
Excellent article. It’s a pity that the current debate entirely lacks the insight that is apparent in the article. All of us have “values” and interpret life through the lens of these values. All of us, including Judges. But if we are to observe that we need to be aware of the values that Judges hold when we select them for Office then perhaps we should also apply the same criteria to our own judgements which we often hold to be “neutral” and uninfluenced by our own values. Most of our values are actually entirely opaque and we frequently make judgements unaware of our own bias. It’s good to have such debates because it makes us aware of our own values and biases and awareness is a good thing. What a pity we are entirely avoiding such a debate at the moment.
The real problem in Irish justice is the slavish adherence to all things English from the wigs and gowns (Symbols of the Crown) to the archaic and hidebound language not to mention the huge number of Acts still in the statute book pre-Partition.
A modern progressive European style country needs a plain language civil and criminal code in which citizens rights to a “fair hearing” are guaranteed and access to justice is the norm not the preserve of the few.
A priority should be a system of “no fault liability” in child birth cases as the current system is a true disgrace costing millions in legal fees and damages only if the claimant is strong enough to fight for 10–2 years against an opponent with countless reserves . It’s hardly an equality of arms and it shames Ireland .
Law is not nuetral, nor is the media all are driven by politicis. Even the Times claiming “Just Facts” is bull.
First thing to do with judicial and legal profession is to bring them into 21st century and make them use plain English. Such rubbish speak they use reading legal documentation is consistently like reading a Shakespeare play.
Surely if I vote I am democratically accountable. Those elected to office should be accountable but to whom. Themselves. Definitely not those who elected them. Under our whip system the politician is accountable to his party.
P.S the new man is a doctor so here is his chance to make a lasting and worthwhile impression as well as making his legacy……introduce no fault liability to the legal system. In fact keep it out the legal system and administer it through an outsourced private entity using a mixture of funds from central government, the insurance industry and the DoJ. Sure it will horrify our Learned friends so what ?
No fault liability will preserve the dignity of the victims of medical “mishaps”, save their sanity, capital and above all save them from years of gruelling battles with rich insurance companies who only care about profits not the suffering of the victims. Come on Dr LEO step up to the plate and demonstrate your desire for an Ireland where all citizens are equal
Just like judge durcan in ennis. He was a member of fine geal!
I will write again even though the Journal didn’t show it the first time. A judge should make a decision on the basis that it is fair and honest. If they don”t do that then they should clear off and let someone else do it. That one of the biggest problem in Ireland judges working fir the system.
Some of these judges liveon another planet
The reality is that corruption is deeply ingrained in our culture. We can explain/excuse this by pointing to our history of oppression etc. But that is history. The phase that we need to progress through right now is the phase of becoming a mature nation where corrupt practice is not necessary in order that our citizens can be guaranteed the rights bestowed upon them in our constitution
This phase/transition is underway but progress is slow. This is because the established system stands to loose if we achieve s full open and just society.
The judiciary is intertwined in the establishment and is of course influenceable by its masters.
Appointments must be removed from political influence and the judiciary itself needs to mature to being totally impartial and independent.
Correction: the Government is meant to be accountable.
very informative article, I can vote for a politician, I have no say in who is appointed to
legal office in this State. I welcome a system where informed, competent, lay people have a role in their appointment. The legal profession holds itself in very high esteem, the idea that they are the only ones who can be involved in the selection of a Judge, is arrogant and elitist.
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