This is where I collect my "ideas". There have been quite a few and I have forgotten or lost many of them, but this is a relatively interesting sampling of the rest.
The reason a helium balloon rises is that helium is lighter than "air" which is a concoction of oxygen, nitrogen, carbon-dioxide, and a variety of trace substances. The reason helium is lighter than air is that helium is less dense than air, meaning that there is less mass in a given volume of helium than there is in an equivalent volume of air. Now, nothing is less dense than a pure vacuum. A vacuum, by definition, contains no matter, and thus has zero mass (and likewise has zero density). If a balloon had a vacuum in it, it would rise with a stronger force than any other conceivable balloon, which means that the balloon could be smaller than a helium balloon to lift an equivalent payload (which makes it cheaper by saving on materials costs, plus allows it to fit into smaller spaces).
The problem is that balloons are pressurized from the inside, and a vacuum has no pressure. If you suck all the air out of an ordinary rubber balloon, or a paper or plastic bag, what does it do? It collapses into a flat sheet with no volume. Since floating (rising) depends on displacement, volume is critical to the successful function of a balloon. My solution is to hold the volume of the balloon with some sort of skeleton. The surfaces of the balloon would be concave (pushed inward) rather than convex (like an ordinary balloon), but the balloon would still have a volume.
One possible skeleton for a cubical balloon. Notice that the basic strategy is to place skeletal rods along the external edges of a polyhedron. Another possibility however (not pictured here) is to project rods through the volume from opposite corners. I am not sure which of these two methods would employ the least (and therefore lightest) total skeletal-rod material (I believe the internal method would work better for a cube, but this may not be the case for other shapes). I am also not absolutely certain which method would allow a greater volume to be maintained after the concave surfaces are pushed in (I believe the external method would work better for a cube, but again, this may not be the case for other shapes).
The question in that case is simple. Can a balloon that has the extra added weight of a skeleton, and also suffering from concave surfaces instead of convex surfaces (which will reduce the volume), get any payoff in lifting capacity when "filled" with a vacuum over a helium filled balloon? This of course depends on what kinds of materials are available for the skeleton and the balloon's surface. Since the lifting force of a floating balloon is measured just like in any force, in newtons (or pounds if you prefer), all that is necessary for the calculation is to compare the difference in the lifting force for a given volume of vacuum compared to the same volume of helium with the difference in weight of the two kinds of balloons (the vacuum balloon has the extra skeleton, plus it will have to be larger in order to contain the same volume because of its concave surfaces). If the difference in lifting force is greater than the difference in balloon weight, then this idea will work, otherwise it won't.
I haven't done any math, but I assume this isn't feasible at the present time. If it were, someone would have invented it already. In the future however, new materials may make this a feasible technology. On the other hand, helium is virtually inert (making is extremely safe) and is really cheap. While a vacuum is also inert and cheap, it may simply be easier to stick with good 'ol helium.
I'm not sure how vacuums are presently created. A number of devices depend on vacuums, so there's no question that someone somewhere has derived a pretty good way to do it. I think the most common way is with simple fans. Fans simply blow the air out of a contained volume and the air density decreases. However, this method cannot possibly create a perfect vacuum. The decrease in density must drop off asymptotically without every reaching zero. I believe there is an easy way to create an absolutely perfect vacuum however (maybe I'm wrong, maybe it doesn't work, I don't know). This is a simply physics experiment that I learned about a long time ago. If you submerge a glass in a bowl of water, turn it upside down, and pull it up out of the water, it will come up completely filled with water even though it is above the waterline. The reason for this is simple. There was no air in the glass to begin with and no way for air to get into the glass, so the external air pressure pushing down on the water in the bowl will push water up into the glass. Now, when the force of the external air equals the force of the water's mass trying to descend out of the glass, the two forces are balanced. This depth is thirty-three feet in sea water and thirty-four feet in fresh water. Beyond that point, the air pressure isn't powerful enough to push the column of water any higher. I believe that pulling this "glass" (which is now a thirty-four foot long tube of course) any higher, must result in a pure vacuum at the top of the tube, and I do mean pure. There wouldn't be a single atom of matter in this space, with the exception of matter vaporizing off of the inside of the tube or off of the surface of the water (which is physically unavoidable. A tungsten container would vaporize very very little). I'm not really sure what the reaction of these materials would be to the presence of a pure vacuum (which would of course make the materials frigidly cold except for heat transmitting through the water and container from the outside). Once this vacuum is attained, sealing it off so that it can be used is easy. Simply slide a door across the tube right above the water level (at thirty-four feet high), and the vacuum is now contained (to the extent that the container doesn't leak). It can now be transported, or otherwise used in whatever fashion is desired. If the materials making up a desired object that uses a vacuum can be submerged under water without suffering damage, these materials could be pushed up through the tube of water into the vacuum before the door is closed off. Now the materials can be constructed into their desired form in a vacuum, which of course means the object itself can contain a small piece of this vacuum if a vacuum is needed in the object, or in some cases, certain materials are so sensitive to matter of any kind that a vacuum is the only place nonvolatile enough to work with them. For example, oxygen has horrible corrosive effects on a wide variety of materials. |
I don't know a whole lot about aerodynamics, but it seems to me like relatively flat airplane wings with hinging flat surfaces on the trailing edge, such as elevators, flaps, and ailerones, probably aren't the most efficient kind of wings. If a wing had a variable curvature over its entire surface, I imagine this would work much better. This could be done in at least two ways. One, a series of small hinged surfaces would at least approximate a true curve better than a single hinge between two fairly large surfaces. Two, if the wing were made of a flexible substance it could actually be coaxed into changing its curvature over a truly curved surface. Assume that this flexible surface tends to spring back to a flat shape. Then, in order to create a curvature, simply bend it some by pulling it together at the ends with a cord or cable. Pulling the cable in would increase the curvature, and releasing the cable (allowing the surface to spring back toward a flat shape) would decrease the curvature. Seems simple enough to me.
Actually, solar robotics of any kind is quite fascinating to me. Sunlight is absolutely totally free. In fact, it's going to waste all around us. Why not simply scoop it up since it's hitting our robot anyway and use it for something. Solar power on a ground-based robot is a serious problem because Earth is far enough away from the sun that the amount of energy that hits a given area at Earth's distance is pretty small. As a result, a robot would have to lug a round some pretty ungainly solar panels. However, flying robots already have tons of surface area, their wings. Once again, I say put these areas, being continually bombarded with solar energy, to good use.
I'm not the first person to suggest solar powered airplanes and gliders, not by a long shot. However, I do think it's really cool. Quite simply, there is enough solar energy hitting the wings of a model glider to power the glider's internal servos. I'm not totally certain that this is the case if a powerful radio transmitter is installed (for remote controlled flight) or if a powered plane (propeller or jet) is being used, but for an autonomous robotic glider that doesn't have to receive instructions from the ground and doesn't use powered flight, there is easily enough energy available. A robotic glider using solar energy could stay aloft literally all day long. There are no batteries that would otherwise run out of steam. It is even possible that there is enough power to charge up batteries for powered flight during the nightime and that the glider could thus stay in the air indefinitely. I might try to build an autonomous robotic glider and if I do, powering it with solar power is something that I may strongly consider incorporating into such a project.
Motion capture is the most common way to animate virtual characters. The summer 2001 movie Final Fantasy uses motion capture to animate all of its characters for example. I believe that in the near future, Hollywood will crumble as computer-generated movies take over the entertainment industry. For a detailed description of this idea, see my mind rambling topic Synthesized voices. We won't be able to create truly virtual characters without allowing them to move freely however. Creating smooth motions of the wide variety that living creatures like humans and animals use is exceedingly difficult.
In the past this has been accomplished by painstakingly moving the skeleton of a virtual character's model in such a way as to appear as smooth as possible. Doing this requires tremendous skill and practice and has moderate results. Motion capture seems like a godsend of a solution. By capturing the motions of real people and animals we can animate virtual characters with perfectly natural motions. The problem is that this requires a real physical person or animal to perform every necessary motion so that it can be recorded.
What I propose is that we use motion capture to define the fitness function for a genetic algorithm. This genetic algorithm will evolve virtual characters that know how to move in fluidic natural ways. These virtual characters' motions will evolve to match the motions of motion-captured real people and animals. I believe this would give us truly virtual characters that would no longer require a performer to carry out each and every needed action. These virtual characters would literally be directed, kind of like a movie-director does. One would simply tell the virtual character to walk from point A to point B. The character could be told that it has a small limp in its right leg. It could be told that it is in a hurry so it better scuttle along as quickly as possible. It could be told it is exhausted and must carry itself in an appropriately tired fashion.
This kind of virtual character will be necessary for a wide variety of technologies that will emerge in the near future. Movies of course will need these characters, but other uses include video games, virtual assistants (tripping around on your computer screen), virtual dance instructors, virtual reality characters for interaction in the next generation of video games, virtual models that model clothing on a website for a consumer before the clothing items are purchased, etc. The list goes on.
Check this out. We all know how to count to ten on our fingers. Well guess what? You can actually count to 31 on one hand and a whopping 1023 on two hands. It's easy. Your fingers represents digit positions in a binary number. That means that with a given number of fingers, X, you can count to 2^X - 1 (where '^' means 'to the power of'). On one hand, there are five fingers, so this is 2^5 - 1, which equals thirty-one. Here are the hand representations for each of the thirty-two numbers in the range zero through thirty-one (right hand palm up or left hand palm down, it doesn't really matter): |
This is an idea I got while reading Edwin A. Abbott's Flatland. Assuming a fourth spatial dimension exists, and assuming beings from that dimension "visit" our dimension by intersecting it (and thus appearing as three-dimensional shapes to us), it is possible to capture certain kinds of shapes and trap them here. In fact, any shape that is not entirely convex should be capturable. I will first show how to capture a two-dimensional creature in one-dimensional space. I will then show how to capture a three-dimensional creature (us) in a two-dimensional space. Finally, I will show how we could capture a fourth-dimensional creature in our three-dimensional space.
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The trick is to allow the being to partially intersect the lower-dimensional space, and then close around its concave structure like a lasso closing around a bull's horns. Notice how this is accomplished when a two-dimensional shape is captured in the first dimension. |
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Now notice how this logic is extrapolated to capture a three-dimensional shape in the second dimension. |
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It should be noted at this point that I have not yet illustrated a way in which the captured shape can be viewed. In the second dimension, after the noose closes around the three-dimensional shape intersecting the second dimension, there is no way to see "through" the noose to view the captured shape. This can be modified however, as shown here. |
Now, how would this analogy extrapolate to the capture and viewing of a fourth-dimensional shape in the third dimension. It is difficult to draw a picture of this scenario for obvious reasons. But imagine a fourth-dimensional shape that is concave in the fourth dimension. Let's assume the fourth-dimensional equivalant of the barbell shape I have used thus far. As this shape intersects the third dimension it will appear as a sphere that appears from nothing and quickly grows as the bulb of the lower bell passes through the third-dimension. This sphere will then begin to shrink as the second half of the lower bell passes through the third-dimension. At this time, if we wrap the three-dimensional equivilant of a lasso (a hollow sphere for all intents and purposes, basically a beachball) around the sphere, it will be captured. In order to escape (in either direction) the intersecting sphere would have to grow in size first, but it cannot do this because of the enclosing ball. It is even possible to recreate the analogy of a window that allows us to view the captured shape. Simply cut a hole in the ball. We can view through the hole into the interior where the captured intersection of the shape resides (a sphere thrashing around inside the ball trying to escape). The shape still cannot escape so long as the window is not expanded to the size of the ball itself. Nifty, huh?
Optical telescopes come in two main varieties: refracting, which use relatively ordinary lenses, like in a magnifying glass, and reflecting, which use parabolic or spherical concave mirrors. Refracting telescopes are extremely expensive compared to reflecting telescopes for the same aperture, but reflecting telescopes use multiple mirrors which must be precisely aligned before satisfactory results can be obtained.
Why not use a fresnel lens? It is extremely lightweight and extremely cheap. I am not the first person in the world to think of this idea, but the only fresnel lens telescopes I am presently aware of are space telescopes. Why hasn't this kind of telescope caught on in the personal use market?
I have no idea why this hasn't become a third kind of consumer-level telescope, and I am highly tempted to build one and see how it performs.
Gotcha! Just kidding.