9 votes

What was that?! Quantifying the impact of a martial arts strike

The basic problem is that you haven't defined what a "good" kick or punch is. Is the purpose make the opponent lose his balance? To inflict the maximum pain? To break bones? To hit a particular ...
  • 11.3k
5 votes
Accepted

Convert Load Deformation (Extension) Data to Stress-Strain Curve

It's fairly complicated. I found an article in The Bone Journal Comparison of three-point bending test and peripheral quantitative computed tomography analysis in the evaluation of the strength of ...
5 votes
Accepted

How to generate a synthetic infrared and red LED signal for SPO2 calculation

Short: (1.) Mindless and without understanding method that would work well. This is as quick and easy as is likely to be possible, should work 'well enough' and would be 'easy enough' to implement ...
5 votes
Accepted

Can the production rate of labs-on-a-chip ever reach the production rate of silicon chips?

Production rates of lab-on-chip fluidic devices can exceed the production rate of silicon ICs easily. Some types of lab-on-chip devices can be fabricated via injection molding. Of course, there are ...
  • 1,045
4 votes
Accepted

What was that?! Quantifying the impact of a martial arts strike

It all comes down to force. We all know Newton's second law: $\vec{F}=m\vec{a}$1. It says that the greater the force that is applied to an object, the greater its acceleration will be (and ...
  • 2,485
4 votes

How is the long term reactivity of implant materials evaluated?

Chronic animal experiment. This is not the only stage of evaluation of the material, but it's a mandatory stage. Chronic means that the animal is survived after implantation for a period of time and ...
  • 1,045
4 votes

Why does blood pressure cuff size matter?

The first clue is in your reference to the succinct description: You may need a large cuff if your arm size is 11 or 12 inches. By 13 inches you do need a large cuff. The brachial artery is ...
  • 9,527
3 votes

Why is the jacket or sheath of fibre optic endoscopes always black?

I really have no idea, but I did come up with the following possibilities. To minimize reflections from the instrument itself. Light reflecting off the endoscope could interfere with the doctor's ...
  • 2,989
3 votes

Why automakers are/should be making medical ventilators?

I think you could hack any poppet valve engine block to create a rapid pressure swing adsorbtion machine, but better to start with a block designed as a compressor in the first place. Lubricating oil ...
  • 3,755
3 votes

Why does blood pressure cuff size matter?

I would guess that there is more than one reason to that (However, I am speculating, since I could not find any technical research on it). But in general the question is what effects can lead to a ...
  • 1,202
3 votes

How does a flexible endoscope turn?

The endoscope has pairs of cords running along the length, which are called angulation wires. The levers on the operator end pull the cords differentially, which makes the tip turn. ( Source; the ...
  • 1,045
2 votes
Accepted

Transducers in cuff-style blood pressure monitors

This is actually a really neat question, and it involves a few engineering and anatomical concepts. Here's what happens when an automatic blood pressure cuff measures your blood pressure: The cuff ...
2 votes

Pump like solenoid but more powerful?

It sounds like you need a Diaphraghm pump. These are self-priming, like solenoid pumps, and come in a wide range of sizes. How far above the water is the highest point in your system compared to the ...
2 votes
Accepted

Is it possible to power bio-chips with blood sugar?

One possible way to do this could be a microbial fuel cell. This has, apparently, been tested ex-vivo: A pacemaker powered by an implantable biofuel cell operating under conditions mimicking the ...
  • 4,651
1 vote

Why automakers are/should be making medical ventilators?

Automotive manufacturing encompasses a wide range of types of devices, many of which are broadly similar in terms of their structure and function to medical devices. e.g. processing electronics, ...
  • 488
1 vote
Accepted

Is biological tissue a Dynamical System and a Nonlinear System?

Generally speaking, any mathematical model that is time dependent will be considered a 'dynamic' system, some engineering descriptions will say dynamic systems are described as systems having the ...
1 vote

how can I solve this error in c++: Exception Unhandled?

I have found the solution! I did these three steps and everything is ok now! 1) I restored my system through: start/create a restore point/ system protection/ system restore/next/next... 2) I work ...
  • 9
1 vote

How is the first image estimate generated in CT scan iterative reconstruction (IR)?

It is difficult to tease out proprietary trade secrets from manufacturing companies; and it is further confusing to deal with misleading terms aimed at applications and clinical handling of these ...
1 vote

Pulse Oximetry, does the decimal matter?

The accepted error in pulse oximtery isn't that good. It's about $\pm$2 % so your additional significant figures are useless. A good review is Aoyagi, T. J Anesth (2003) 17: 259. https://doi.org/10....
  • 401
1 vote

Polarity of a relative angle - Knee joint angle

Yes, you are correct. See sketch below.
  • 7,696
1 vote

Measuring gas flow from a low-output device

You can use a float type flowmeter: A float sits in a conically expanding tube, the higher the flow rate the higher the float hovers. In the closest catalog I have at hand, the smallest meter is for ...
  • 4,651
1 vote

Surgical steel and part production

When I was a boy; We made a eight shapes ( as I remember) of parts like that for Ritter. They were produced by investment casting using 17 - 4 PH. There was a die witness line that carried over from ...
  • 5,932
1 vote

Positron Emission Tomography: How to get from photon count to radioactivity?

I happen to be a cancer patient and have had the PET-CT. The way they explained it to me is after giving you a rapidly decaying radioactive sugar with a half-life of about one hour which has one ...
  • 21.2k
1 vote

RULA upper arm angle

Why not simply record back angle wrt vertical axis in your data then state your assumption that you base your analysis on. Then, the results can be analysed both ways.
  • 14.2k
1 vote

Does anybody have information on how to refurbish an old laser rod (alexandrite or Nd Yag)? )

Well, rather obviously you need to find an optics house which will take on the task of regrinding the ends to optical flatness while maintaining perpendicularity of the faces to the long axis. ...
1 vote

Calculate elasticity of rubber balloon

You need to be careful with the subscripts, e.g in the equation for $\sigma$, which $R$ do you want? However, what you seem to be saying is: $$E \propto \frac{p}{R}$$ and, if you take $p$ and $R$ as ...
  • 11
1 vote

Easily accessible material for maximum grip on a prosthetic hand?

One very easy solution is to spray the required surfaces with latex based contact adhesive. This is fairly tacky when cured and the spray will also give a bit of texture. Alternatively liquid latex ...
  • 15.1k
1 vote

Measurement of girth of abdomen (automatic) using body impedance measurement

Measuring the resistance of a person's abdomen will not be a good method to determine their girth because the resistivity varies by more than two orders of magnitude. According to the Wikipedia ...
1 vote

What was that?! Quantifying the impact of a martial arts strike

A martial artist's live strikes can be quantified between practitioners using force applied as pounds per square inch. The basic premise is (of course) force equals mass times acceleration. The ...
  • 111
1 vote

What was that?! Quantifying the impact of a martial arts strike

With a strike or kick, you move (more or less) you whole body, connect a hand or foot or whatnot to your target and if your technique is good, the target will deform far more than your body. I think ...
  • 4,651

Only top scored, non community-wiki answers of a minimum length are eligible