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Inducting high frequency current on human skin capable of lighting a lightbulb. (Like Tesla)

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Jaroslav Já

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So me and my classmate decided to do this as our project. So far we have tried to induce some current via standart mutual induction of two coils, and we are quite far from making this work for human skin. From what I know we will need frequency around 1MHz (approx resonance frequency of human body) and really strong magnetic field. We think we could 'support' the skin effect by soaking the hand in water helping us avoid any potential harmfull effect of the current.
I was wondering what are your thoughts about this and whether anyone else tried this as well and if you could give us some useful tips.
 
So me and my classmate decided to do this as our project. So far we have tried to induce some current via standart mutual induction of two coils, and we are quite far from making this work for human skin.

Have you read about diathermy? There is a wealth of information on it, including new research.

From what I know we will need frequency around 1MHz (approx resonance frequency of human body) and really strong magnetic field.

Can you provide a reference for that "fact?" 1 MHz is right in the middle of the AM radio band. There is a 50 KW station in Chicago at 1.0 MHz (WMVP). I don't feel any different driving by its antennas than when I drive by any other station.

We think we could 'support' the skin effect by soaking the hand in water helping us avoid any potential harmfull effect of the current.

Not quite sure what you plan to do. How well does 1 MHz radio penetrate water? What do you mean by "support the skin effect." Why do you think water would prevent harmful effects? Don't forget, you are mostly water.

As a general comment, your question is rather vague and seems to be based on some faulty assumptions about behavior of the human body. Again, just search on diathermy, some of which uses a frequency of about 1 MHz, and read about the various methods that have evolved from the earliest machines.

John
 
Our informations are based on Tesla's work (On light and other high frequency phenomena, 1893) where he talks about this experiment.
To the skin effect - it is unharmful at high frequencies indeed, you can easily find some experiments on youtube or anywhere else. The difference is we are trying to make something like that wireless.

To the water - thanks to the skin effect, at such high frequencies, the current will flow mostly on the very top of our skin, where, unfortunately, is not much water. Soaking the skin with water should reduce resistance.

I am sorry for my lack of skills to explain myself correctly in English. This topic was mostly pointed to people who might have some experience with this experiment and would know what I mean.
 
The 'skin effect'[edit]
The dangers of contact with high-frequency electrical current are sometimes perceived as being less than at lower frequencies, because the subject usually does not feel pain or a 'shock'. This is often erroneously attributed to skin effect, a phenomenon that tends to inhibit alternating current from flowing inside conducting media. It was thought that in the body, Tesla currents travelled close to the skin surface, making them safer than lower-frequency electric currents.
Although skin effect limits Tesla currents to the outer fraction of an inch in metal conductors, the 'skin depth' of human flesh at typical Tesla coil frequencies is still of the order of 60 inches (150 cm) or more.[47][48][49][50][51] This means high-frequency currents will still preferentially flow through deeper, better conducting, portions of an experimenter's body such as the circulatory and nervous systems. The reason for the lack of pain is that a human being's nervous system does not sense the flow of potentially dangerous electrical currents above 15–20 kHz; essentially, for nerves to be activated, a significant number of ions must cross their membranes before the current (and hence voltage) reverses. Since the body no longer provides a warning 'shock', novices may touch the output streamers of small Tesla coils without feeling painful shocks. However, anecdotal evidence among Tesla coil experimenters indicates temporary tissue damage may still occur and be observed as muscle pain, joint pain, or tingling for hours or even days afterwards. This is believed to be caused by the damaging effects of internal current flow, and is especially common with continuous wave, solid state or vacuum tube Tesla coils operating at relatively low frequencies (10's to 100's of kHz). It is possible to generate very high frequency currents (tens to hundreds of megahertz) that do have a smaller penetration depth in flesh. These are often used for medical and therapeutic purposes such as electrocauterization and diathermy. The designs of early diathermy machines were based on Tesla coils or Oudin coils.
Large Tesla coils and magnifiers can deliver dangerous levels of high-frequency current, and they can also develop significantly higher voltages (often 250,000–500,000 volts, or more). Because of the higher voltages, large systems can deliver higher energy, potentially lethal, repetitive high-voltage capacitor discharges from their top terminals. Doubling the output voltage quadruples the electrostatic energy stored in a given top terminal capacitance. If an unwary experimenter accidentally places himself in path of the high-voltage capacitor discharge to ground, the low current electric shock can cause involuntary spasms of major muscle groups and may induce life-threatening ventricular fibrillation and cardiac arrest. Even lower power vacuum tube or solid state Tesla coils can deliver RF currents capable of causing temporary internal tissue, nerve, or joint damage through Joule heating. In addition, an RF arc can carbonize flesh, causing a painful and dangerous bone-deep RF burn that may take months to heal. Because of these risks, knowledgeable experimenters avoid contact with streamers from all but the smallest systems. Professionals usually use other means of protection such as a Faraday cage or a metallic mail suit to prevent dangerous currents from entering their bodies.
The most serious dangers associated with Tesla coil operation are associated with the primary circuit. It is capable of delivering a sufficient current at a significant voltage to stop the heart of a careless experimenter. Because these components are not the source of the trademark visual or auditory coil effects, they may easily be overlooked as the chief source of hazard. Should a high-frequency arc strike the exposed primary coil while, at the same time, another arc has also been allowed to strike to a person, the ionized gas of the two arcs forms a circuit that may conduct lethal, low-frequency current from the primary into the person.
Further, great care must be taken when working on the primary section of a coil even when it has been disconnected from its power source for some time. The tank capacitors can remain charged for days with enough energy to deliver a fatal shock. Proper designs always include 'bleeder resistors' to bleed off stored charge from the capacitors. In addition, a safety shorting operation is performed on each capacitor before any internal work is performed.[52]

From that it doesn't sound to me like you can do this without frying yourself....
 
Take a peace of soaked leather and try the experiment. The closest thing I can think of is a fresh cadaver.

Just be careful you don't make a Frankenstein.
 
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