Pages

Wednesday, July 11, 2012

LONGTIME PLAYING-ABOUT WITH ELECTROSTATIC PHYSICS


WHAT A SHOCKING CAREER

LONGTIME PLAYING-ABOUT WITH ELECTROSTATIC PHYSICS

(c)1999 William J. Beaty

How did I get involved with "static" electricity? What is my level of expertise? Why should you trust what I say, since many of my statements contradict your textbooks? Here's my "Electrostatics Timeline."
I started out normal, at least somewhat normal. I only turned into a raving Electrostatics Freak over many years. As 4-yr old kids long ago, my little brother and I spent lots of time chasing each other in slow motion while scuffing on the livingroom rug and dueling with zapping fingers. Cat noses did not go unnoticed.
A few years of living on Guam was an interruption, since Guam (pacific, Marianas Islands) is an alien, high-humidity zero-electrification zone as far as environmental high-voltage effects are concerned. However, I had one memorable experience when I was 6. My father was a grade school teacher, and at one point I was with him in an empty classroom for a few hours while he was doing paperwork. Drawing on the chalkboard wore thin, so I asked about this box of strange science-stuff on his desk. It was test-tubes full of grey metallic-looking stuff called "pith," black shiny rods, and fur. I don't remember what he called it, but he said it didn't work. I tried rubbing the rod on the fur, and found that the rod would CAUSE MOTION IN THE PITH FRAGMENTS FROM AN INCH AWAY!!! For a 6-yr old, this was profoundly stunning magic. Also, the real world contradicted my father's statements, and I discovered this on my own. Knowing what I know now, I see that the experiment shouldn't have worked. Guam is way too humid for static-electricity demonstrations. However, we were in a heavily-airconditioned building, and all the moisture-exuding students had been gone for hours. The air conditioner must have finally been able to lower the tropical jungle r.h. to barely within the range where rabbit fur can electrify a hard-rubber rod. I think my father tried the demonstration the next day, and said it still didn't work. (A classroom full of kids creates lots of humidity.) Heh heh. The world can talk to little kids, and show us a secret.
Back in upstate New York, in 7th grade gym class, there was a small "wrestling/weights room" with padded walls, Sorbothane floor pads, and a weight-lifting set. This was nerd heaven, since the coach would leave us alone in order to supervise the basketball jocks. The rest of the kids would practice "weightlifting" by grabbing 2lb iron weight-disks, then walking slowly around the perimiter of the room while leaning and dragging our shoulders on the plastic pads. Yes, gym class can be fun! :) We "dueled" with the iron disks, and the resulting sparks were NASTY. Even if they lept from disk to disk, we could feel our arm-muscles significantly twitch. (Looking back on this, I see that our body-voltages must have been relatively astronomical when compared with the voltage range of normal rug-scuffing.) I quickly noticed that two electrified kids could not deliver shocks, and if EVERYBODY was electrified, nobody could zap each other. However, *I* still could! I would step off the Sorbothane pads for a moment, lose my charge imbalance to the conductive concrete floor, then go around delivering painful zaps because of my "grounded" state. I became skilled at tracking who was carrying charge imbalances and who was not, trying to almost "see" the voltage state of all the individual kids (the better to zap you with, my dear.) Obviously a powerful childhood experience, eh? :)
When I was 13, I received a much-coveted subscription to Popular Science for my birthday, and was having delerious visions of all the cool stuff I was going to build when someday I had money. Then I got the 1972 April and May and issues. Motors. Plastic motors. Plastic motors which can be POWERED BY THE SKY! Dr. Oleg D. Jefimenko's famous Electrostatic Motor articles were in those issues; describing all sorts of exotic rotating devices made from foil layers and gleaming polished plexiglas. The Elmira Flood of 1972 hit a week later, wiping out my room, and I thought I'd never see those magazine issues again. Yet what bizarre things lurk just under the thin crust of our ordinary mundane everyday reality, squirrled away in places few people ever look, and if they do look they don't see it. Motors powered by the sky.
In 8th grade physical science class, there was a VandeGraaff machine in the rear storage room. This was used for higher grades, and I never saw it run. However, while waiting for class to begin, I would sneak back there and spin the motor drive by hand, which caused the VDG sphere to suck in the ground-ball on it's spring-loaded rod, until a 2-inch spark would go "bap!"
Disgusted by the arrogant scientific dispargement of Kirlian Photography and Pyramid Power, I went to college and became an electrical engineer instead of a physicist.
Decades later I finally encountered an electrostatic voltmeter, and for the first time I was able to verify the actual human body-voltage values which arise from rug-scuffing. I had always imagined that people could easily develop 30KV with respect to the earth. I was working at Sykes Datatronics (Ra cha cha, NY!) when the production line was down because of fried motherboards (pre-Apple-II, 6502, 8" floppies.) Electrostatic damage was judged to be the culprit, and the new and expensive conveyor system had to be modified. The engineering department rented a couple of "Electrometers" (Electrostatic Voltmeters,) so I immediately got hold of one and went scuffing around upon various carpets. I was amazed to find that my measured body voltage WRT ground would only hit 4.0KV at max, even though I was able to create 5mm sparks from fingertip to ground. My biased perception of voltage values created by that sorbothane-padded weight-room came to an end. Later I used that voltmeter extensively for FCC testing of modem transformers. Some tech people have Black Bakelite "VOM" meters in their early electronics experience. I have a thousand-billion ohm electronic voltmeter with a 10,000v full-scale range. Truely an "alternate mental toolbox."
I stumbled across an ad for "Electronics Dept. Head" for the Boston Museum of Science, and actually landed the job. Effing Incredible!!! The best techi job in the entire world. (low pay though.) Boston has Dr. VandeGraaff's original gigantic particle-accelerator, and uses it to give lightning shows. The small museum library also had an extensive collection of electrostatics books, including those long-lost E-motor articles from Pop. Electronics, as well as feet thick of article clippings, build-it projects for bizarre-o kilovoltage devices of all kinds, ancient dusty physics journal articles, etc. Over one stretch of weeks I must have spent four hours a day there, swallowing it all. Then the musuem embarked on its Electricity/Electronics exhibit.

Dr. Jefimenko missed something huge: a powerful social effect, as well as an opportunity to harness it. Why wasn't the world already crawling with electrostatic motors? Simple: nobody ever messes with them and gets interested in them. But what about Jefimenko's incredible motors? Well, we need lathes, milling machines, and precision machine-shop skills to build those heavy-duty sky-voltage motors in his articles. They are elegant and impressive museum pieces, but what child would ever look at an impressive museum piece and think "hey... *I* could build that!" ? "Impressive" cancels out their inspiration. But that's what our upcoming electronics exhibit might end up looking like: elegant and impressive barriers to learning. Like hell it would.
I got to try my hand at electrostatic motor design, and came up with a nice, high-speed 3-sector disk motor built from the requisite gleaming plexiglas, as well as unique voltage-viewers panels, attempts at electrostatic levitation demos, visible e-beams and magnets, exposing the museum visitors to AC kilovoltage, and other seriously cool stuff which was necessarily compatible with national museum esthetic standards. (The excess material is now on my Electrostatics page!) But I also included something aimed at the modern versions of my long-ago 6-yr-old self: an exotic electrostatic motor made from garbage. The Hall of Electricity even now has one case containing a hand-cranked VandeGraaff machine, and also in that case is my subtle and subversive message aimed at all those weirdo kids who might be a bit like I once was. Look! A motor made from old pop cans and tinfoil, which turns by itself because of invisible magic. Science is supposed to be impressive, important, and horrendously complicated, right? The better to stroke mankind's overblown ego with. But ANYBODY could build such a thing. Your parents turn the crank and walk on to the next exhibit unit. But *YOU* know what that crude little device implies, don't you. I can feel you out there, looking at it.
Well, the internet arrives and all that is moot. Everyone and his (little) brother can now stumble into this expanding nest of High Voltage shennanigans, and go off to build bottle motors, VDG machines, create lightning from water, perform strange high-voltage demonstrations... or just learn the secret skill for scuffing up a really big zap. Cool ideas spread by the same dynamics which control disease epidemics. I just wanna be a "Typhoid Mary" of electrostatics. But this is a disease which has a chance of IMPROVING the infected population, eh? :)
Me, I'm still out here working at a normal 9-5 programming job (although once I did get to play "Professional ESD Remediation Expert" by tracking down mysterious resetting in a microprocessor-array "smart conveyor" system using nothing but a Radio Shack cliplead and a 50-cent voltage sniffer.) Perhaps I could do more if I pursued funding, but the pursuit of funding is crawling with petty politics and timesucking bureaucratic paper shuffling. Perhaps the pursuit of funding would wreck all of this webpage stuff, since webpage stuff only needs time, not money. With a good job and time for a hobby on the side, what more do I need?
If there's one thing I want you to get from all this, it's the fact that this world is totally jam-packed full of profound depths of unplumbed mysteries, hidden just below the surface. But there is a problem. We are blind. We can't see them. And any people who don't believe in those mysteries cannot feel them out there, waiting for them, hovering just around the next corner out of sight. "Normal" people know for a fact that science has discovered EVERYTHING. They are convinced that, maybe a few decades ago, there were still some interesting things left to discover, but today they're all gone. Star Trek technology? Don't make them laugh. Their physics proves that it's all impossible. Humankind is a self-centered predator whose highest goal is to steal success from his fellows, humankind will never reach the stars, any other belief is unscientific Sci-fi fantasy.
And the famous American astronomer/skeptic Simon Newcomb proved in 1904 that flying machines were impossible. Hence all researchers exept the crackpots were convinced to drop any flying-machine research, and to loudly ridicule the Wright Brothers for years after their successful flights; during the years they were giving public demonstrations in Dayton, OH, and no scientist, reporter, or government official ever showed up. Some rare people suspect that there MIGHT be a small lesson in that. The majority never learn.

"New and stirring things are belittled because if they are not belittled, the humiliating question arises, 'Why then are you not taking part in them?' " - H. G. Wells
 

Tuesday, July 10, 2012

Build an Electrostatic Motor

Build an Electrostatic Motor

CAPACITOR MOTORS

CAPACITOR MOTORS
In 1889, Karl Zipernowsky, a Hungarian engineer (co-inventor of practical electrical transformers), constructed a new type of electrostatic motor, which was derived from Thomson's quadrant electrometer. The rotor of this motor (Fig. 36) consisted of two pairs of aluminum sectors insulated from each other and from the rest of the apparatus. The stator consisted of four double (hollow) sectors of brass enclosing the rotor. The rotor was fitted with a commutator in four parts, by means of which the sectors of the rotor were charged oppositely to those sectors of the stator into which they were entering and identically to those sectors of the stator which they were leaving. An interesting property of this motor was that it could operate from high-voltage dc as well as from high-voltage ac sources.
Inasmuch as Zipernowsky's motor operated as a result of the electric forces exerted by one charged conducting plate upon a second charged conducting plate (which are the same forces that act upon the two plates of a capacitor) it constituted what is now called an electrostatic "capacitor motor".
Since capacitor motors do not require sparks or a corona discharge for their operation, they can operate, at least in principle, from as low a voltage as one desires to use. This is one of their important advantages and is one of the reasons that such motors have been given considerable attention in recent years. Furthermore, as already indicated, capacitor motors can operate not only from dc sources, but also from ac sources. Finally, when powered by an ac source, they can operate both as synchronous and asynchronous motors (Zipernowsky's original motor operated from ac as an asynchronous motor).
A synchronous capacitor-type electrostatic motor is merely a multi-electrode capacitor motor without a commutator, the proper charging of the rotor being accomplished by continuously supplying an ac voltage of proper frequency between the stator and the rotor. It is easy to see that if the rotor moves by one electrode in one period of the supply voltage, then the ac voltage accomplishes the same effect as that accomplished by a do voltage with a commutator. The synchronous velocity is therefore 2 &pi ƒ/N, where ƒ is the frequency of the supply voltage and N is the number of the electrodes....

Electrostatic Motor Power and Propulsion Using Potential Energy of Ions

 Electrostatic Motor Power and Propulsion Using Potential Energy of Ions

Most people are familiar with motors that use magnetic fields to produce motion. However, electrostatic fields can also be used to build motors and other devices. A build up of electrostatic charge exposed to another charge can produce a force. Just like the magnetic force, it can be repulsive or attractive.

In his paper titled, "SOLUTE ION COULOMB FORCE MONOPOLE MOTOR AND SOLUTE ION LINEAR ALIGNMENT PROPULSION" and patent application "US 2010/0199632 A1 Solute Ion Coulomb Force Acceleration and Electric Field Monopole Passive Voltage Source" he describes multiple possible setups in which the potential energy in salt water can be tapped. It is stated that approximately 3% or 30,000 parts per million of seawater are actually sodium and chlorine ions. An ion is a molecule or atom that has a different number of protons (that produce positive charge) than electrons (that produce negative charge). These charged ions hold a huge potential energy. Apparently, this potential energy is what keeps sodium chloride from sinking in water, even though NaCl is more than three times as heavy as the water molecule. The dipole polarity of water is a strong attraction-repulsion to the charged ions, making the weight different irrelevant.

He proposes separating the ions by running a current through two electrodes with a potential voltage difference. This would attract positive sodium ions to the negative electrode and negative chlorine ions to the positive electrode. The build up of charge would create a large attractive force between these two electrodes of opposite charge. It is proposed that aerogel could be used as electrode material because it has a very large surface area. Since electric charge accumulates on the surface of a material and not inside of a material this could increase the force produced. However, other materials such as bronze could be used.

The patent describes how multiple electrodes or "monopoles" (electric charges are not considered to be dipoles but point charges) of electric charge can be arranged in motor configurations or configurations that produce thrust. In one example, you could place several monopoles of the same polarity on a rotor disc. Then you could place a stator monopole of the same polarity near the edge of the rotor. Both the stator and rotor monopoles would be in repulsion. By using electrically insulating material you could shield the rotor or stator in such a way to make the rotor spin.

Interestingly, in this setup only a small amount of charge could produce a large amount of force. In the paper it is stated, "Only a very small amount of charge in each monopole is required, i.e., 10 millicoulombs, (less than a milligram) to provide a force of about 44,000 Newtons (almost 10,000 lbs) if monopoles are separated by 0.5 meters (assuming this equation for Coulomb’s Law for this application is directly applicable without modification-this may not be the case)."

In addition to powering a motor this technology could produce jet ions in salt water. In this case the force produced by the monopoles would be working directly against the ions in the water. Perhaps a new jet ski could be made using this technology!

One important thing to mention is that this technology is not claimed to break the laws of thermodynamics. It does not "create" energy. The input energy to separate the charged ions is much less than the energy produced by the electrostatic force. However, the energy was stored in the potential energy of the ions. This technology just converts the potential energy of the ions into kinetic energy.

Please realize this technology has not been tested. It is still an idea at this point in time. But the author of the patent and paper claim it is all grounded in science. The Coulomb Force is a fact. The ability to separate ions in salt water using a potential voltage difference between electrodes is a fact. The stored potential energy in ions is a fact. The ability to shield electrostatic forces is a fact. This theory simply tries to put it all together to produce a useful technology.
# # #

Electrostatic Motor Plans

Electrostatic Motor Plans
SIMPLE, SENSITIVE VOLTAGE MOTOR USING 2-LITER SODA BOTTLES

                            - William J. Beaty,        1988 Museum of Science

Here's a simple electrostatic motor that's based on 2-liter soda bottles and aluminum foil. It's construction does not require access to a machine shop. It draws a fraction of a microamp during operation, and can run at unexpectedly high speeds (1000 RPM!) It runs on a minimum of 5000 volts DC, which can be had from several different low-current electrostatic energy sources.

Any of the following can power this motor:

    Van de Graaff electrostatic generator (expensive unless home-built)
    Wimshurst electrostatic generator (expensive)
    Negative ion generator, try this one, it runs off a 9v batt.
    Aluminum foil on a TV screen (dangerous?)
    M. Foster's Cheap High Voltage
    Lenny R's PVC Pipe generator
    A very large electrophorus (low humidity required)
    "Kelvin's Thunderstorm" waterdrop machine (very feeble, barely works)
    High-voltage DC supply (dangerous, avoid it unless skilled with HV!)
    Jefimenko-style sky antenna (kite-lifted or balloon-lifted wire with needles at top)
    Or, with some practice, even with a balloon and a piece of fur can sometimes work.
    Batteries won't work, you need High Voltage

One of these motors is featured in the Electricity exhibit at the Museum of Science in Boston, powered by a hand-cranked Van de Graaff machine.
PARTS:

    three 2-liter pop bottles, at least one with a METAL cap
    roll of aluminum foil
    rubber cement
    silicone caulk
    13" metal rod, 1/8" dia. (could use coathanger)
    Two 8" pieces of solid copper wire, or coathanger
    wood plank (or metal, or plastic) for the base
    duct tape
    hookup wire for attaching the power supply


CONSTRUCTION:

Metal Rod


Cut the rod so it's about 1 in. longer than the middle bottle. Sharpen the rod using a file. Drill a hole in the center of the plank using a drill bit slightly smaller than the sharpened rod. Carefully force the rod into the plank, unsharpened end first. (Note: coathanger wire will work as the center rod, sort of. But it's very wobbly. 1/8" welding rod works much better.)(Note: instead of filing a sharp point, try attaching a piece of a sharpened pencil to the top of the rod. The sharp graphite point makes a good bearing.)

"Rotor" Bottle



Find the exact center of the bottom of the middle bottle, and drill a hole there that's slightly larger than the rod diameter. When slid onto the sharpened rod, the bottle should spin very freely. If the hole is too big, the bottle will rattle around and make the brushes drag on its surface
If you can find a bottle with a metal cap, make a dimple in the center of the cap. The dimple is there so the point on the rod will have something to ride in to stay centered. Take care not to poke through the metal bottlecap with the sharp rod! If you can't find a metal cap, glue a hard object such as a small glass test tube into the bottle cap. If you use the pencil point mentioned above, a plastic bottle cap might work (I haven't tried this.) You'll still have to make a dimple in the plastic somehow.

Precisely cut three broad strips of aluminum foil so they are just wide enough to give a 1/2" spaces when attached to the center bottle. You want the middle bottle to have three regions of foil, with half-inch gaps between the regions. Trim the corners of the foil so they are round, and test-fit them on the bottle and trim as needed.
Glue the foil to the center bottle as shown in the drawing. (It doesn't matter if the shiney side of the foil faces out or in.) I used rubber cement to glue the foil strips. I coated the whole bottle with cement, coated one side of each pre-cut foil strip, allowed the glue to dry a couple of minutes, then CAREFULLY layed on the strips and burnished them down with a spoon as I went. The end result should look like an aluminum coating on the bottle, with three broad foil sections separated by 1/2in gaps running vertically. No part of each foil section should touch any other foil section. Bubbles in the foil don't hurt anything, and can be punctured with a pin and flattened with a spoon. Instead of glue and foil, you might instead try using a roll of adhesive aluminum foil tape available at some hardware stores.

Two "Stator" Bottles

Glue large sheets of foil around the entire center areas of both of the two 'stator' bottles, leaving a 2 in. foil-free space at the bottoms. The bottom must remain clear of foil, and no foil on these bottles should come close to touching the wooden base or close to any duct tape you might use to connect the stator bottles to the base.

Commutator "brush" wires

The commutators (or "brushes") are pieces of heavy wire or coathanger 8in long, each attached to a stator bottle, and each extending sideways so their ends are very near (but not touching) the rotor bottle surface. After attaching them to the bottles, bend the tips so they point towards the surface of the rotor bottle. See the diagram and photos.
I attached them to the stator bottles by bending the wire ends into an S-shape and embedding the S-shaped part in silicone caulk on the foil bottles. After the glue sets, the remaining short ends of each S-shape should be bent so they make solid contact with the bottle's foil. Don't let the silicone insulate the wire from the foil, because the stator foil and the commutator wire must both be electrically connected to one of the power supply terminals.

Attaching the Stator Bottles

Attach the two stator bottles to the plank so they are spaced about 1/2" from the rotor bottle. I used nuts and bolts through the bottoms, which allowed me to rotate the bottles a bit for easy adjustment of the spacing between the commutator wire tips and the center bottle. (Yes, it was really hard to position the bolts inside the bottles!)
If you use tape to attach the stator bottles, make sure it DOES NOT reach up to contact the foil. Duct tape, masking tape and wood are slightly conductive, and when the humidity is high, they can provide an unwanted leakage path to ground, preventing motor operation.

The Bearing

The metal-cap-with-dimple bearing is pretty crude. I improved it by obtaining a 1/4" diameter test tube, cutting the bottom 1/2" off it (by nicking with a file and snapping by hand with gloves.) This I glued into the exact center of the bottlecap. The sharpened rod spun nicely against the glass. Avoid dropping the center bottle suddenly down onto the metal rod, or the sharp point will shatter the glass bearing.
Mark Kinsler has a better suggestion: use a bottle with a plastic cap, and screw a short sheet-rock screw through it so the point of the screw extends downwards into the bottle. Now use a wooden rod instead of a metal one, and screw a small phillips-head screw into the end of the rod. Place the bottle on the wooden rod so that the point of the sheet-rock screw rides in the head of the screw at the top of the wooden rod. He mentions that the slightest air current will make this bottle turn.


Stacked motor

Stacked motor
Because of its simple structure and ease of assembling, this motor can easily be stacked to get higher power. Figure 4 shows an example of stacked motors. The motor in figure 4 has 40 layers. Figure 5 shows the internal structure of the stacked motor. Stator films and slider films are stacked together with spacer films, and their edges are held by metal pins and acrylic plates. Interval between each stator film (or each slider film) is 0.35mm. To utilize both surface of stator films, each layer consists of one stator film and two slider films as shown in the figure. So, the total number of stator films are 40, whereas the number of sliders are 80.

The metal pins for stator works also as electric feed. Stator electrodes are connected to those metal pins via washer made of conductive rubber.

Whole motor (figure 4) are held in plastic case and immersed in dielectric liquid. Both side of slider are connected to output wires, which lead to outside of the case. Thrust force is transmitted through these wires.

The total weight of the motor, including case and dielectric liquid, is 110g.













Results of measurements of thrust force and power are described in the following.

Figure 6 shows a relationship between voltage and thrust force when the motor is driven at 10Hz. The motor could operate over 100V applied voltage, and its thrust force was proportional to square of applied voltage. The maximum applicable voltage was limited under 800V due to dielectric breakdown of stator film.

Figure 7 shows characteristics of thrust force and power against operation frequency. The plot was obtained at 800V applied voltage. We obtained larger thrust force at lower frequency, and maximum thrust force was 8N. Power was larger at higher frequency, and maximum power was 0.5W. 









Electrostatic Motor design on Bill Beaty's Science Hobbyist

Electrostatic Motor design on Bill Beaty's Science Hobbyist
I found the design for this motor on Bill Beaty's Science Hobbyist site and just had to build one

This photo shows the finished motor sitting on top of my Cockcroft-Walton voltage multiplier, ready to run.  The three, one quart, high density polyethylene bottles are sitting on a piece of 3/4" thick ultra high molecular weight polyethylene board.  The two end bottles are wrapped with aluminum foil duct tape and bolted to the board with short lengths of 1/4-20 threaded 18-8 stainless steel rod and nuts.  The rod on the left bottle extends through the board and contacts the output terminal of the CW.  The middle bottle has three 2" X 6" strips of foil tape and is supported on a needle bearing ground from a length of 1/4" drill rod.  The rod sits in a 1/4" hole drilled 1/2" deep into the board and passes through a 1/4" hole in the bottom of the bottle.  The point of the rod rests in a dimple made in a piece of 1/32" Teflon sheet which is held in the mouth of the bottle by the screw cap.  Taped to each end bottle is a 1" wide strip of aluminum roof flashing, with the far end bent at 90º and cut to make a pair of sharp points.  The right hand bottle sits on a short length of flashing which is used for the ground connection.

This is a no flash (hence long shutter time) photo of the motor in operation.  The three aluminum foil sectors on the center bottle are blurred into a gray band by rapid rotation.  Several arcs are visible between the left hand brush and the center bottle.  More can be seen between the center bottle and the right hand bottle.  This is not ideal for motor operation, but makes a nice picture.  At lower voltages (~40,000 volts) there is no arcing and the center bottle spins even faster.  A digital multimeter spliced into the ground connection showed a current draw of 40 mA under these conditions.

This sketch should help clarify some of the construction details I gave above.