Category Archives: Research

Cool Robot Locomotion: Transforms from Wheeled to Walking For Stairs and Rough Terrain

This is a very cool engineering solution. Wheeled locomotion is very efficient on the right terrain. This transformation lets the robot switch to climb stairs and handle rough terrain very nicely. A team of mechanical engineers at National Taiwan University built this energy-efficient leg-wheel hybrid mobile robot. From their description:

Compared to most hybrid platforms, which have separate mechanisms and actuators for wheels and legs, our leg-wheel hybrid mobile robot, Quattroped, uses a “transformation mechanism” that deforms a specific portion of the body to act as a wheel or a leg. From a geometrical point of view, a wheel usually has a circular rim and a rotational axis located at the center of the rim. The rim contacts the ground and the rotational axis connects to the robot body at a point hereafter referred to as the “hip joint.” In general, with wheeled locomotion on flat ground, the wheel rotates continuously and the ground-contact point of the wheel is located directly below the hip joint with a fixed distance. In contrast, in legged locomotion the leg moves in a periodic manner and there is no specific geometrical configuration between the hip joint and the ground-contact point; thereby, the relative position of the legs varies frequently and periodically during locomotion.

Based on this observation, shifting the hip joint out of the center of the circular rim and changing the continuous rotation motion to other motion patterns implies the locomotion switches from wheeled mode to legged mode. This motivated us to design a mechanism that directly controls the relative position of the circular rim with respect to the hip joint so it can generate both wheeled and legged motions. Because the circular rim is a 2-dimensional object, the most straightforward method to achieve this goal is to add a second degree of freedom (DOF) that can adjust the relative position of the hip joint to the center of the circular rim along the radial direction. The motions of the two DOFs are also orthogonal to each other. In addition, the same set of actuation power can be efficiently used in both wheeled and legged modes.

Healthy Diet, Healthy Living, Healthy Weight

Living and eating healthily is tricky but not entirely confusing. The whole area of eating healthy food and what is a healthy weight is one where the scientific inquiry process and the complexity of scientific research on what is healthy for us is clear. Scientists study various issues and learn things but creating simple rules has proven difficult. Different studies seem to show benefits of contradictory advice, advice once seen as wise is now seen as wrong…

This is an area I am far from knowledgable about. Still I try to pay some attention as I like being healthy. Being sick is the quickest way to appreciate how great it is to be healthy. From various things I have skimmed it seems there is more evidence from several studies about how difficult it is to lose weight. Our bodies seem to work against our efforts.

And this, it seems to me, makes the problem of increasing childhood and teen obesity even more important to deal with as soon as issues arise.

It seems to me the most important thing to take from this, is the importance of maintaining a healthy weight: since you can’t just easily make up for a bad year of weight gain. I am not sure why I haven’t seen this note in most of what I have read – I suspect it is our reluctance to make value judgements about what is healthy. The problem I see with that is, the best advice we have is confusing enough without people with more knowledge being reluctant to state their best advice given the current knowledge. That doesn’t mean the suggestions are right, but at least they are educated guesses.

I try to eat relatively healthily. Which for me means taking steps to increase the amount of vegetables I eat (especially greens and some fiber) and decrease the amount of sweets and heavily processed food I eat (I still eat way too much heavily processed food). And I try to exercise as it seems to have many benefits including helping make up for some weaknesses in your diet (like eating too many calories and too many “empty calories). In my opinion (which on this topic may well not be worth much) eating a bit more stuff that really isn’t so good for you and exercising more is an easier tradeoff than trying to eat perfectly and do the minimum amount of exercise needed to stay healthy.

I also eat yogurt – I like it and the beneficial benefits of some bacteria seems likely. I heard recently something that surprised me which is that the beneficial bacteria remain for close to 2 weeks. I figured they would be gone in a couple days. I only heard that from one source (I can’t remember now but some seemingly knowledgable source – scientist researching the area), so it might not be accurate but it was interesting.

Here is an example of one of these health studies. They find that a low protein diet resulted in a loss of “lean weight” (muscle…) and more fat than a comparable diet with more protein. The same weight with a higher percentage of fat is not a good thing for human health. Thus the message is that a lower protein diet has this risk that must be considered (and therefor higher protein diets may well be wise). Of course things get much more complicated than that when we actually try to live by a diet.

Effect of Dietary Protein Content on Weight Gain, Energy Expenditure, and Body Composition During Overeating

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Memory is Stored by Turning on Genes in Neurons (to Alter Connection Between Neurons)

I find these kind of stories so interesting. I really have so little understanding of genes. I knew memory had something to do with altering connections between neurons. I had no idea that required turning on many genes in those neurons. Life really is amazing.

Neuroscientists identify a master controller of memory

When you experience a new event, your brain encodes a memory of it by altering the connections between neurons. This requires turning on many genes in those neurons.
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Lin and her colleagues found that Npas4 turns on a series of other genes that modify the brain’s internal wiring by adjusting the strength of synapses, or connections between neurons. “This is a gene that can connect from experience to the eventual changing of the circuit,” says [Yingxi] Lin

So far, the researchers have identified only a few of the genes regulated by Npas4, but they suspect there could be hundreds more. Npas4 is a transcription factor, meaning it controls the copying of other genes into messenger RNA — the genetic material that carries protein-building instructions from the nucleus to the rest of the cell. The MIT experiments showed that Npas4 binds to the activation sites of specific genes and directs an enzyme called RNA polymerase II to start copying them.

“Npas4 is providing this instructive signal,” Ramamoorthi says. “It’s telling the polymerase to land at certain genes, and without it, the polymerase doesn’t know where to go. It’s just floating around in the nucleus.”

When the researchers knocked out the gene for Npas4, they found that mice could not remember their fearful conditioning. They also found that this effect could be produced by knocking out the gene just in the CA3 region of the hippocampus. Knocking it out in other parts of the hippocampus, however, had no effect.

One of the things I aim to do in 2012 is read a few more books on biology and genes. I find it incredible what are genes actually are doing to allow us to live our lives. And I am also very ignorant on the whole area. So hopefully I can have some fun next year learning about it.

Can Just A Few Minute of Exercise a Day Prevent Diabetes?

That just 1 minute of exercise a day could help prevent diabetes seems to good to be true. But research at the University of Bath indicates it might be true. I am a bit of a soft touch for seeing the benefits of exercise. And I also love health care that focuses on achieving healthy lives instead of what most of the spending focuses on: treating illness.

Performing short cycle sprints three times a week could be enough to prevent and possibly treat Type 2 diabetes researchers at the University of Bath believe.

Volunteers were asked to perform two 20-second cycle sprints, three times per week (but really this works out to under 10 minutes of total time including warm up). After six weeks researchers saw a 28% improvement in their insulin function. Type 2 diabetes occurs when blood sugar levels build up to dangerously high levels due to reduced insulin function, often caused by a sedentary lifestyle. The condition can cause life-threatening complications to the heart, kidneys, eyes and limbs, and has huge costs (monetarily and to people’s lives).

Regular exercise can help keep blood sugar levels low but busy lifestyles and lack of motivation mean 66% of the population is not getting the recommended five 30-minute sessions of moderate exercise a week.

Dr Niels Vollaard who is leading the study, said: “Our muscles have sugar stores, called glycogen, for use during exercise. To restock these after exercise the muscle needs to take up sugar from the blood. In inactive people there is less need for the muscles to do this, which can lead to poor sensitivity to insulin, high blood sugar levels, and eventually type 2 diabetes… We already knew that very intense sprint training can improve insulin sensitivity but we wanted to see if the exercise sessions could be made easier and shorter.”

In the study the resistance on the exercise bikes could be rapidly increased so volunteers were able to briefly exercise at much higher intensities than they would otherwise be able to achieve. With an undemanding warm-up and cool-down the total time of each session was only 10 minutes.

This type of study is very helpful in identifying solutions that will allow more people to lead healthy lives and save our economies large amount of money. Medical studies can’t be accepted on face value. They are often not confirmed by future studies and therefore it is unwise to rely on the results of 1 study. The results provide interesting information but need to be confirmed (and in the area of studies on human health this has been shown to be problematic – are health is quite a tricky area to study).

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Using a Virus to Improve Solar-cell Efficiency Over 30%

Solar and wind energy are making great strides, and are already contributing significantly to providing relatively clean energy.

Researchers at MIT have found a way to make significant improvements to the power-conversion efficiency of solar cells by enlisting the services of tiny viruses to perform detailed assembly work at the microscopic level.

In a solar cell, sunlight hits a light-harvesting material, causing it to release electrons that can be harnessed to produce an electric current. The research, is based on findings that carbon nanotubes — microscopic, hollow cylinders of pure carbon — can enhance the efficiency of electron collection from a solar cell’s surface.

Previous attempts to use the nanotubes, however, had been thwarted by two problems. First, the making of carbon nanotubes generally produces a mix of two types, some of which act as semiconductors (sometimes allowing an electric current to flow, sometimes not) or metals (which act like wires, allowing current to flow easily). The new research, for the first time, showed that the effects of these two types tend to be different, because the semiconducting nanotubes can enhance the performance of solar cells, but the metallic ones have the opposite effect. Second, nanotubes tend to clump together, which reduces their effectiveness.

And that’s where viruses come to the rescue. Graduate students Xiangnan Dang and Hyunjung Yi — working with Angela Belcher, the W. M. Keck Professor of Energy, and several other researchers — found that a genetically engineered version of a virus called M13, which normally infects bacteria, can be used to control the arrangement of the nanotubes on a surface, keeping the tubes separate so they can’t short out the circuits, and keeping the tubes apart so they don’t clump.

The system the researchers tested used a type of solar cell known as dye-sensitized solar cells, a lightweight and inexpensive type where the active layer is composed of titanium dioxide, rather than the silicon used in conventional solar cells. But the same technique could be applied to other types as well, including quantum-dot and organic solar cells, the researchers say. In their tests, adding the virus-built structures enhanced the power conversion efficiency to 10.6% from 8% — almost a one-third improvement.

Read the full press release

Rats Show Empathy-driven Behavior

Rats free trapped companions, even when given choice of chocolate instead

The experiments, designed by psychology graduate student and first author Inbal Ben-Ami Bartal with co-authors Decety and Peggy Mason, placed two rats that normally share a cage into a special test arena. One rat was held in a restrainer device — a closed tube with a door that can be nudged open from the outside. The second rat roamed free in the cage around the restrainer, able to see and hear the trapped cagemate but not required to take action.

The researchers observed that the free rat acted more agitated when its cagemate was restrained, compared to its activity when the rat was placed in a cage with an empty restrainer. This response offered evidence of an “emotional contagion,” a frequently observed phenomenon in humans and animals in which a subject shares in the fear, distress or even pain suffered by another subject.

While emotional contagion is the simplest form of empathy, the rats’ subsequent actions clearly comprised active helping behavior, a far more complex expression of empathy. After several daily restraint sessions, the free rat learned how to open the restrainer door and free its cagemate. Though slow to act at first, once the rat discovered the ability to free its companion, it would take action almost immediately upon placement in the test arena.

“We are not training these rats in any way,” Bartal said. “These rats are learning because they are motivated by something internal. We’re not showing them how to open the door, they don’t get any previous exposure on opening the door, and it’s hard to open the door. But they keep trying and trying, and it eventually works.”

To control for motivations other than empathy that would lead the rat to free its companion, the researchers conducted further experiments. When a stuffed toy rat was placed in the restrainer, the free rat did not open the door. When opening the restrainer door released his companion into a separate compartment, the free rat continued to nudge open the door, ruling out the reward of social interaction as motivation. The experiments left behavior motivated by empathy as the simplest explanation for the rats’ behavior.

“There was no other reason to take this action, except to terminate the distress of the trapped rats,” Bartal said. “In the rat model world, seeing the same behavior repeated over and over basically means that this action is rewarding to the rat.”

As a test of the power of this reward, another experiment was designed to give the free rats a choice: free their companion or feast on chocolate. Two restrainers were placed in the cage with the rat, one containing the cagemate, another containing a pile of chocolate chips. Though the free rat had the option of eating all the chocolate before freeing its companion, the rat was equally likely to open the restrainer containing the cagemate before opening the chocolate container.

“That was very compelling,” said Mason, Professor in Neurobiology. “It said to us that essentially helping their cagemate is on a par with chocolate. He can hog the entire chocolate stash if he wanted to, and he does not. We were shocked.”

Now that this model of empathic behavior has been established, the researchers are carrying out additional experiments. Because not every rat learned to open the door and free its companion, studies can compare these individuals to look for the biological source of these behavioral differences. Early results suggested that females were more likely to become door openers than males, perhaps reflecting the important role of empathy in motherhood and providing another avenue for study…

Interesting study. My guess is this is the kind of thing those that don’t like science would deride. I believe in the value of science. I believe in the value of learning. I believe that such experiments are what drives science forward. I believe if you want your economy to benefit from investing in science you should be encouraging hundreds and thousands of such experiments. Funding for this study was provided by The National Science Foundation (NSF), and others.

I am thankful that more and more countries are willing to invest in science, especially since the USA is showing an increasing anti-science attitude. I would rather the USA continue to believe in the value of science and other countries looked to increase investments. But, it is much better that other countries increase their interest in science, and willingness to invest in science, to more than make up for the USA’s decisions to reduce the appreciation for science than for the world to just lose do to a decrease in investments in science.

Stand with Science – Late is Better than Never

The USA public has made very bad decisions in who to send to Washington DC to spend our money (and the money of our children and grandchildren). We have wasted hundreds of billions that could have been spent more wisely. I happen to think investing in science and engineering is important for a societies economic health. The problem the USA has is we have chosen to waste lots of money for decades, at some point you run out of money (yes the USA government doesn’t really, as they can print it, but essentially they do – in practical terms).

I would certainly eliminate tax breaks for trust fund babies and trust fund grandchildren (while your grandchildren are going to be left holding the bag for the spending those elected by us, the grandchildren of the rich often get huge trust funds with no taxes being paid at all). But most of the people we have elected want to give trust fund babies huge payoffs. I would cut much spending in government – spending 5% less in 2020 than we did this year would be fine with me. But we don’t elect people that support that. I would support not adding new extensions to tax cuts sold with false claims and again supported by those we continue to elect. I wouldn’t allow the financial industry subverting of markets. But again we elect people that do allow that. And when the bill comes due for letting them take tens and hundreds of millions in individual profits in the good years, we can either let the economy go into a depression (maybe) or spend hundreds of billions to trillions bailing out those institutions our politicians let threaten the economy.

It might not seem fair, but there are consequences to allowing our political system to waste huge amounts of money paying of special interests for decades. And investing in science and engineering has been a casualty and will likely continue to be. Eventually you run out of money, even for the stuff that matters. Trying to fight for politicians that will put the interests of the country ahead of their donors is not something you can do effectively only when your interests are directly threatened. At that point things may already be too bad to be saved.

I have been writing about the failed political system for quite awhile now. I wrote awhile back that Hillary Clinton’s idea to tripple the number of GRFP awards was something I thought was very smart economically. But even then I questioned if we could afford it, if we refused to do anything else different (just adding new spending isn’t what the country needed).

Even in the state the politicians we continue to elect (we elect the same people election after election – there is no confusion about what they will do) we can debate what to cut and for something we spend so little on as investing science and engineering we can even easily increase that spending and not have any real impact on cutting overall spending. But those we have elected don’t show much interest in investing in science and engineering overall.

The USA continues to invest a good deal in science and engineering. But the difference in focus today versus the 1960’s is dramatic. The USA will continue to do well in the realm of science. The advantages gained over decades leave us in a hugely beneficial position – and one that takes other countries decades to catch up to. Now some countries have been working on that for decades now, and are doing very well. China, hasn’t been at it quite as long but has been making amazingly fast progress (similar to the amazing economic story).

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YouTube SpaceLab Experiment Competition

YouTube SpaceLab is an open competition inviting 14 – 18 year olds (anywhere in the world) to create an idea for a science experiment in space. You don’t have to actually do the experiment, you just have to record yourself explaining it.

Entries must have be submitted on YouTube by 07:59 GMT on December 8th.

The winning experiments will be conducted on the International Space Station (ISS) and beamed live on YouTube for the whole planet to see.

Winners get the choice to either watch the rocket blast off with your idea on it in Japan or take a specially tailored astronaut training course in Russia when you turn 18. There are other amazing prizes for the runners-up too.

Here is an example entry from 3 students in UK on an experiment to learn about quorum sensing by bacteria in the micro gravity of space.

Dennis Hong, Virginia Tech Mechanical Engineering Professor, Leading Robotics Innovation

Dennis Hong is the U.S. star in humanoid robotics

Hong came by his interest in science naturally. He was born in 1971 on the exclusive Palos Verdes Peninsula, outside Los Angeles, and his father, Yong Shik Hong, worked as an aerospace engineer at the federally funded Aerospace Corp. The family returned to Seoul in 1974 so the elder Hong could lead South Korea’s short-range missile program, at the bidding of then-President Park Chung Hee.

Korean fathers of that era were strict and remote. Hong’s father was engaged and intellectually indulgent. He installed a work bench in Dennis’s room when he was 4, complete with a hammer and saw. He led the children in chemistry experiments and brought home model airplanes from America.

Dennis Hong built things with scraps of wood and metal and bits of plastic. He disassembled toys and stored the parts in a chest beneath his bed.

“We spent a lot of time building things and breaking things,” said Julie Hong, Hong’s older sister. “He was the one who broke things the most and built things the most.”
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Hong traveled to America to complete his university study, following his father’s credo, “Big fish must swim in the big sea.” He earned a bachelor’s in mechanical engineering at the University of Wisconsin and a master’s and doctorate at Purdue.

Dennis’ success illustrates several themes repeated in posts on this blog: the USA attracting talent from overseas, kids curiosity and exposure to science and engineering leading to great things, the value of strong science and engineering programs and professors. Robotics continue to progress very quickly. The economic impact of robotics is large already (largely in manufacturing) and will continue to grow dramatically. Likely robots will find their way into much more diverse areas over the next 2 decades. The Robotics and Mechanisms Laboratory, lead by Dennis Hong, seems poised to play a big role in that future.

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Epigenetic Effects on DNA from Living Conditions in Childhood Persist Well Into Middle Age

Family living conditions in childhood are associated with significant effects in DNA that persist well into middle age, according to new research by Canadian and British scientists.

The team, based at McGill University in Montreal, University of British Columbia in Vancouver and the UCL Institute of Child Health in London looked for gene methylation associated with social and economic factors in early life. They found clear differences in gene methylation between those brought up in families with very high and very low standards of living. More than twice as many methylation differences were associated with the combined effect of the wealth, housing conditions and occupation of parents (that is, early upbringing) than were associated with the current socio-economic circumstances in adulthood. (1252 differences as opposed to 545).

I find Epigenetics to be a very interesting area. My basic understanding as I grew up was that you inherited your genes. But epigenetics explores how your genes change over time. This has been a very active area of research recently. Your DNA remains the same during your life. But the way those genes are expressed changes.

I don’t know of any research supporting the idea I mention in this example, but, to explain the concept in a simple way: you may carry genes in your DNA for processing food in different ways. If you have very limited diet the way your body reacts could be to express genes that specialize in maximizing the acquisition of nutrition from food. And it could be that your body sets these expressions based on your conditions when young; if later, your diet changes you may have set those genes to be expressed in a certain way. Again this is an example to try and explain the concept, not something where I know of research that supports evidence for this example.

The findings by these universities, were unfortunately published in a closed way. Universities should not support the closing of scientific knowledge. Several universities, that support open science, require open publication of scientific research. It is unfortunate some universities continue to support closed science.

The research could provide major evidence as to why the health disadvantages known to be associated with low socio-economic position can remain for life, despite later improvement in living conditions. The study set out to explore the way early life conditions might become ‘biologically-embedded’ and so continue to influence health, for better or worse, throughout life. The scientists decided to look at DNA methylation, a so-called epigenetic modification that is linked to enduring changes in gene activity and hence potential health risks. (Broadly, methylation of a gene at a significant point in the DNA reduces the activity of the gene.)

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