What are Problocks? How do they work?
Why are Problocks important? How do they fit in with nanotechnology and utility fog?
How do ProBlocks compare with other modular robotics projects?
Imagine a time when the structures that people want to build can simply assemble themselves! Using a number of identical cubes or Programmable Blocks (ProBlocks) with electromagnets in their 6 faces and simple electronics inside, structures can be built block by block by themselves. Starting with just one seed block, other blocks will be attracted to the faces of that seed block that have their magnets turned on. These other blocks will attract other blocks and so on, until the entire structure is built.
The outer part of a space station can self-assemble from a large bag of ProBlocks floating in space. An underwater dwelling can self-assemble from a bag of ProBlocks on the ocean floor. The average person could use ProBlocks around the house. Instead of having many specialized items that are only used for certain occasions, a set of ProBlocks floating in a liquid medium can be called upon to self-assemble into whatever is needed at the moment. The user could self-assemble a chair, table, desk, stairs, partition, bed frame, or counter when it is needed, then dissolve it back into ProBlocks when it is no longer needed.
When self-assembling a structure, a number of blocks float around in a medium enclosed by a box. The system picks one block in the medium and provides it with the design plan, what its position is in the design, and what layer it is in. The structure will be built in layers from inner to outer layers. This first block uses this information to turn on electromagnets on its faces that will be adjacent to other blocks in the final structure. When a floating block comes close to a magnet that is on, it will move to the block attracting it and attach to the structure. The block that this new block attaches to will tell the new block the design plan, the new block's position in it, and what layer it is in. The new block uses this information to turn on its appropriate magnets. This process continues until the entire structure is built.
For example, suppose the user wanted to self-assemble a structure that would look like this:
*
*
* * *
* *
* *
If we number the blocks in this design like this:
1
2
3 4 5
6 7
8 9
The plan for this design can be shown in chart from like this:
|
Block Number |
Up |
Down |
Left |
Right |
|
1 |
--- |
2/0 |
--- |
--- |
|
2 |
1/0 |
3/0 |
--- |
--- |
|
3 |
2/0 |
6/0 |
--- |
4/0 |
|
4 |
--- |
--- |
3/0 |
5/0 |
|
5 |
--- |
7/0 |
4/0 |
--- |
|
6 |
3/0 |
8/0 |
--- |
--- |
|
7 |
5/0 |
9/0 |
--- |
--- |
|
8 |
6/0 |
--- |
--- |
--- |
|
9 |
7/0 |
--- |
--- |
--- |
The numbers in this chart represent the block number either Up, Down, Left, or Right from the block number shown in the leftmost column / the layer that that block number is in. In this example, all of the blocks are in layer 0, the innermost and only layer. If the system picks block number 3 as the first block, it will transmit this plan data to the block and also the fact that this block is block number 3. This first block will look up its data in the row of data for block number 3. It will find that in the final structure, a block will be attached to its Up side, Down side, and Right side. Therefore it will turn on its Up side, Down side, and Right side electromagnets. Soon one of the floating blocks will be attracted to one of these sides. The attracted block will line up along side of the first block and will receive the plan data and its block number from the first block. The first block can find the block number of the attached block by noticing which side was attached to and then looking up the block number in the table. For example, if a block attaches to the Right side of block number 3, the table shows that the number of the block to the right of block number 3 is number 4.
The description above is a bit simplified. It didn't discuss the reason for layers and how they are implemented. The reason that the blocks are assembled in layers is so that the outside of the structure doesn't get assembled before the inside. If the outside got assembled first, no blocks could get into the interior to complete the structure. To implement the restriction that the structure gets built in layers from the inside out, two things must be done. First, the system computer that analyses the plan data must determine which blocks are in which layers. Second, the blocks that have attached to the structure must have a way of knowing when the layer they are in has been completed. Until it is, they must only turn on the electromagnets on faces that will be next to blocks in the same or inner layers as themselves.
Basically, the system computer finds the layers in the structure by peeling off the blocks from the outside in, layer by layer. Starting from a block on the outside surface, the computer traverses the outside of the structure until it ends up back at the block it started at. Then it goes onto the next layer inside until all the blocks have been assigned a layer number.
The blocks that are self-assembling have to continue communicating with each other even after the plan, layer, and block number data have been transferred. When a block is attached to the layer presently being assembled, this fact is communicated to all the other blocks in the layer. These blocks are keeping a count of the number of blocks that have attached in this layer so far. When they all see that the count has reached the total expected amount, they all turn on their electromagnets in faces that will be attached to blocks in the next layer.
For more detailed information on this system, contact B K Services.
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Why are ProBlocks important and how do they relate to Nanotechnology and Utility fog?
The ProBlocks as described above are meant to be used in a preliminary demonstration system to show how the technology works. These are Phase One ProBlocks. The ProBlocks are held together by magnetic force only and therefore have little practical value. I wouldn't sit on a chair made of Phase One ProBlocks!
Phase Two ProBlocks will have locking pins activated by solenoids to secure the connections between ProBlocks. This makes for a much stronger structure with lower power requirements. The solenoids, which also act as the attracting electromagnets, can be turned off as soon as the locking pins connect the ProBlocks. The ProBlock system may need to include Transport Robots at this phase. Transport Robots will be able to connect to ProBlocks and navigate, allowing them to bring ProBlocks to sites in the self-assembling structure where they are needed. This will reduce the time it takes structures to self-assemble, as the structure will not have to wait for a ProBlock to randomly drift by close enough to be attracted by electromagnetism. Phase Two ProBlocks can self-assemble into household structures like chairs, tables, steps, bed frames and other things that are needed at one moment but may need to be "recycled" back to individual ProBlocks when they are no longer needed. They can also be used to self-assemble large structures where human assembly is costly and/or dangerous, such as underwater labs or space structures.
Phase Three ProBlocks will be able to expand and contract along all three axes. Each ProBlock will be made up of 8 internal cubes, each being half as long, wide, and deep as the entire ProBlock. Motorized threaded rods will connect these 8 cubes so that any three pairs of 4; front 4 and back 4, top 4 and bottom 4, or left 4 and right 4 can be moved apart. This movement of pairs will cause the ProBlock to become twice as long along any of its three axes. This internal movement, along with the action of the locking pins, will allow ProBlocks to crawl over each other. This will allow easier self-assembly and also the ability of assembled structures to transform themselves or "shape-shift". It will also give ProBlock assembled structures motion and mobility. Phase Three ProBlocks can be assembled into general-purpose robots capable of motion and mobility. As technology improves, they can be shrunk down in size and used as "Utility fog (see below) and for other nanotechnology related functions.
ProBlocks eventually will come in different sizes to suit the types of structures they will be building. ProBlocks that will be used to build space stations, moon bases, underwater labs, and other buildings will be on the order of feet in size. ProBlocks used inside buildings will be on the order of inches or possibly smaller. At some point, technology will advance to the point where ProBlocks can be made on the micro and then nano scale. Then they will be able to be used in all the applications discussed as applications of nanotechnology. For example, they can be used inside the body to repair damage.
Nanotechnology is the science of building structures atom by atom. Tiny Assemblers, robots capable of moving and placing individual atoms, will do this building. Nanotechnology will come about when we can make Assemblers that can follow a plan to build structures atom by atom. We don't know if Assemblers can be built or if they can actually make useful large-scale structures. How long would it take to build a big structure atom by atom? There is some debate over whether Assemblers should be built at all, due to what is called the "gray goo" problem. Assemblers could make other Assemblers from free material. Many could be made for little cost. Anyone who had one Assembler and the plan to make more could easily make as many as they want and sell as many as they want. They could become widespread and could be misused. Anyone with one Assembler could use it to make as many as they wanted, and then could program them all to make useless junk or unwanted structures (gray goo), possibly using up raw materials.
Its hard to build an Assembler but easy to build a ProBlock. An Assembler needs to small enough to manipulate atoms but it needs a computer and processes for motion. These have to be invented and implemented. The Assembler has to find its way around structures it is building and must be able to find and identify the atoms it needs to build with. It may take thousands of Assemblers to build one new Assembler and billions to make a large structure. Each proto-Assembler, the first ones built, would have to be built "by hand" using a process much more complicated than making ICs. ProBlocks can be built easily using today's technology. All are identical so economies of scale can be achieved. As ProBlock systems are sold, revenue is generated and can be used to improve to the next generation of ProBlocks. Nanotech companies generate no revenue until the first Assemblers are built, if ever. Concepts invented for ProBlock structures can be used for nanotechnology, such as motion and assembly in layers. Nanotech built structures need to be built in layers from the inside out the way ProBlocks assemble. It may also be possible that the first Assemblers built will be, or will be made by nano-sized ProBlock structures.
Instead of striving to build a universal Assembler of questionable utility and controllability, we should build ProBlocks. The supply of ProBlocks would be limited to the amount produced; they would not be unlimited. Therefore, they could not create a "gray goo" problem. At first ProBlocks will assemble into jagged structures with a large power requirement but as the utility of the concept is proven, work can be done to shrink the size of individual ProBlocks. This parallels the progress of computer graphics. When computer screens could only display low-resolution graphics, a diagonal line appeared as a staircase. Now that computers have high-resolution graphics, a diagonal line appears to be much smoother. As ProBlocks shrink in size, the structures that they assemble into will be much smoother. They will also require less force for cohesion, hence less power. Each ProBlock has a computer inside it, so structures built contain a network of computers running in parallel. Input and Output could be via light sensitivity/reflectivity or sound, speech or tones. Also, if ProBlocks were able to expand and contract along any of its axes, structures assembled would be capable of motion.
As ProBlocks shrink, they will be able to be used as a "Utility fog". This is defined as a collection of robots small enough to be floating around in the air like dust. These robots can hook up with each other with their "hands" to create structures out of "thin air". Applications discussed for Utility fog include a virtual "air bag" where the floating robots team up to create a cushioning material in the event of a crash. It is interesting to speculate if the robots could respond fast enough to somehow absorb or divert an incoming bullet. Also, could a Utility fog respond to a chemical or biological attack to surround and seal off a person from contamination? Another application discussed is in Virtual reality. If two people are away from each other but some form of communication is available, each person's fog robots could transform into a model of the other person and move and change in real time, to create the illusion that the other person is right there with you.
No one knows what the future holds. Some companies will respond to events and others will create the future. We believe that it is important to build ProBlocks at whatever level of technology is available at any given time. We feel that Phase One ProBlocks are useful for "proof of concept", to demonstrate their ability and work out implementation details. We feel that there will be a market for Phase Two ProBlocks which can be built inexpensively since they are all identical and therefore subject to economy of scale. Revenue generated by the sale of Phase Two ProBlock systems will be used to create Phase Three ProBlocks. Only time will tell what all the applications of micro and nano sized Phase Three ProBlocks will be.
How do ProBlocks compare with other modular robotics projects?
Modular robots are systems made of groups of identical or similar subsystems. I'll confine this discussion to systems that use cubic sub-units. Several other groups are working on projects that are similar to ProBlocks. I will discuss two of these projects and how they compare to ProBlocks. Please click through to their web sites for more information about them.
In the UK, there are 2 teams working together on related projects. They are the Fractal Robots project and the Brixels project, identified herein as Sliders. These systems are similar to ProBlocks in that they are also made up of quantities of identical cubed shaped devices. The difference between ProBlocks and Sliders is in the way they assemble. ProBlocks are Floaters, they float freely and individually in an enclosed system and attach to other ProBlocks that attract them. Sliders slide along the faces of their adjacent Sliders which they must be pre-attached to. This is accomplished by having either an interlocking mechanical drive system or an electromagnetic system that moves one or more Slider across others. The interlocking drive mechanism also serves to securely lock the individual units to each other.
The powerful advantage of having this Sliding ability is that Sliding systems can "Shape-shift". They can change their shape in real time. They can move from one place to another using a tank-tread type of locomotion or even using a walking motion with 3 pairs of legs. Phase One or Two ProBlocks can assemble into a static structure and later disassemble, but Sliders can assemble into a structure that can move internally as well as externally in the environment.
At the PARC research lab, there is a team working on TeleCubes. TeleCubes are also cube shaped devices, but they are able to telescope to twice their normal length in each of the 3 dimensions. This is done by lengthening a telescoping arm that attaches the face to be moved to the rest of the device. Each face is subdivided into 4 quadrants. Two diagonally opposing quadrants contain switching permanent magnets while the remaining 2 have material that is easily attracted by magnetic fields. The switching permanent magnets can be switched between an attracting or non-attracting state. This is done by aligning or mis-aligning a 4 by 4 grid of permanent magnets whose North or South pole faces out of the face. When the grid of magnets are aligned, they project out their magnetic field. When they are not aligned, the magnetic fields of the permanent magnets remain inside the quadrant, so no magnetic attraction is projected out.
TeleCubes are also capable of "Shape-shifting". The individual blocks don't slide over each other, they are passed from one to another, bridging a gap of one block size in the process. The magnetic attraction is said to be more than strong enough to pull the weight of individual units, but some bending of the telescoping arm is said to occur when passing a unit over an open space.
Further comparison and analysis to follow soon...