Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Why women wiggling in high heels could help improve prosthetic limbs and robots

09.05.2012
People walking normally, women tottering in high heels and ostriches strutting all exert the same forces on the ground despite very differently-shaped feet, according to research funded by the Wellcome Trust and the Biotechnology and Biological Sciences Research Council. The finding suggests that prosthetic lower limbs and robots' legs could be made more efficient by making them less human-like and more like the prosthetics used by 'Blade Runner' Oscar Pistorius.

Walking involves a repeated process referred to by scientists as 'crash, vault, push' – landing ('crashing') on the heel, vaulting over the stationary leg and then pushing off with the toes. This is the most economical way of walking and, as research published today in the Journal of the Royal Society Interface shows, the force exerted on the ground is the same for people walking normally or in high heels and for ostriches.

Dr Tatjana Hubel from the Royal Veterinary College explains: "Despite vastly differing arrangements of joints and hip wiggles, humans walking normally, women in extremely high heels and ostriches all produce strikingly similar forces when walking. This is the most mechanically economical way of walking. We do everything we can to make the forces follow the same pattern, which is why for example women wiggle their bottoms when they're in high heels. The question for us is, why is the human foot shaped the way that it is and not, say, like an ostrich's?"

When scientists model how the leg moves, they tend to simplify the movement and view the leg as a stick with a block on top (the body) which moves in an inverted pendulum motion. In this simplified model, the shape of the human foot does not make sense. But in fact, the human leg is more complicated than this; it contains muscles that likely evolved out of a tension between being optimised for walking and being more efficient at running. As humans are intelligent and able to plan and use tools, being able to move quickly to catch a prey or to evade a predator is not essential.

The shape of the human foot means that when the foot is flat on the ground, all the force goes through the ankles, allowing the muscles to support the weight of the body whilst being largely unloaded during the 'vault' stage. When muscles bear a load, they get tired easily, even if they are doing no work. For example, if we hold our arms outstretched, after a few minutes they will grow tired; by comparison, a JCB digger can extend its arm indefinitely.

The researchers believe this finding may have implications for the design of better prosthetic limbs for above-knee amputees and for the legs of humanoid robots. These might be improved by bearing more resemblance to an ostrich leg than that of a human.

Dr Jim Usherwood, a Wellcome Trust Senior Research Fellow at the Royal Veterinary College, explains: "If you want to make a good prosthetic foot but don't care what it looks like, you should put the motor – in this case, the ankle – as far up the leg as possible, where it can provide the power without making the feet heavy and hard to swing backwards and forwards. There's no point in putting the motor at the end of the foot, where it makes the leg more difficult to swing forwards – important in both walking and running.

"Some clever prosthetics copy the ankle and are very human-like, which is fine for prosthetics to replace the foot, but for above-knee amputee, a typical prosthetic leg which is very human-like is heavy and hard to move around. It's much better to have an ostrich foot at the end of a very lightweight leg.

An example of this kind of prosthetic already in use are the blades used by Paralympic athlete Oscar Pistorius – the 'Blade Runner'. These blades are light, springy and without a heel, similar to an ostrich's legs, which are optimised for running from predators rather than for walking.

Jen Middleton | EurekAlert!
Further information:
http://www.wellcome.ac.uk

More articles from Interdisciplinary Research:

nachricht Fighting myocardial infarction with nanoparticle tandems
04.12.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Virtual Reality for Bacteria
01.12.2017 | Institute of Science and Technology Austria

All articles from Interdisciplinary Research >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

Im Focus: A thermometer for the oceans

Measurement of noble gases in Antarctic ice cores

The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Polymers Based on Boron?

18.01.2018 | Life Sciences

Bioengineered soft microfibers improve T-cell production

18.01.2018 | Life Sciences

World’s oldest known oxygen oasis discovered

18.01.2018 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>