Nano-motors For Microbots

Smivs writes "The BBC are reporting on the development of tiny motors the size of a grain of salt which could power surgical Microbots. Some surgical procedures are hindered by the size or inflexibility of current instruments. For example, the labyrinthine network of blood vessels in the brain prevents the use of catheters threaded through larger blood vessels. Researchers have long envisioned that trends of miniaturisation would lead to tiny robots that could get around easily in the body. The problem until now has been powering them. Conventional electric motors do not perform as well as they are scaled down in size. As they approach millimetre dimensions, they barely have the power to overcome the resistance in their bearings. Now, research reported in the Journal of Micromechanics and Microengineering has demonstrated a motor about 1/4mm wide, about the width of two human hairs."

Re:Seriously.

[Anonymous Coward]

So that is how the Borg will originally have developed...

Still gonna get stuck?

[JakartaDean]

Isn't that still too big to get through a capillary? Eventually they'll still get stuck somewhere, I'd imagine, and then you get a little tiny blood clot in a capillary. Maybe that's not a problem in the brain, I don't know. I still don't think you'd want millions of them blocking random capillaries and killing random nerve cells.

Re:Sizes

[Thanshin]

That's like saying, it's the size of a common green pea (about 0.5cm diameter) when in fact it's the size of a medium size citrus lime. That's like comparing Jessica Alba with This unkown person

For some reason, I'd guess one or both links are nsfw.

Re:Sizes

[mangu]

Divide a loaf of bread between 8 people, do you work out what 0.125 of the loaf is then weigh each piece off or do you just split into halves repeatedly ?

That's really useful to know. But one of the guys isn't hungry, how do we split the loaf among seven people?

take Pi for instance. 22/7 is exact - 3.142 is far from exact

Huh? Do you live in some state that has legislated the value of pi? In my calculator, (3.142 - pi) equals 0.000407, while (22 / 7 - pi) equals 0.00126, which means the decimal approximation you gave is three times more exact than the fraction.

Analogue watches convey the information you need, ie. how long until ... or how long past. Digital watches just give you a figure which you then have to convert into your desired answer.

That's why for some applications analog instruments are better than digital ones. When you are fine tuning an electronic equipment, for instance, it's often better to use an analog multimeter because the movement of a needle gives a better visualization of a peak value than a string of changing digits. But the analog multimeter is calibrated with the exact same scale as the digital equipment.

Analog vs. digital has nothing to do with decimal vs. arbitrary multiples. A digital watch gives time in the same duodecimal units as the digital watch, which makes it so hard to perform calculations involving time.

If it takes me twenty minutes to paint a door, how long will it take me to paint twenty three doors? Answer: multiply 20 * 23 = 460 minutes, divide by 60, that's seven, 460 - 7 * 60 = 40, the remainder is minutes, so the answer is seven hours and forty minutes.

If a board is twenty centimeters wide, how wide are twenty three boards? Answer: multiply 20 * 23 = 460, move the decimal point two digits to get 4.60 meters.

Why can't you Americans face the simple truth that the arithmetic we use has ten different digits, which means it's much simpler to divide by ten than by any other number?

Do the (dismal) math

[Ancient_Hacker]

If you do the math, the prospects for tiny motors is supremely dismal.

You see there's a basic problem-- the torque goes down as the cube of the motor's length, while the friction goes down as the square. In addition magnetics don't work well when you get down to the size of magnetic domains.

By the time you get down to the grain of salt size, motors can just barely overcome friction. Any smaller and they can't even turn over. You might notice in TFA there's no clear indication they've gotten one to rotate at all. Not surprising.

I would not bet any agricultural properties on this.