Spherigear TransmissionOskarPuzzle2024-10-23 | Spherigear TransmissionZiggutwist Too - Why dont those disk just come out?OskarPuzzle2024-05-11 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/ziggutwist-too or shapeways.com/product/XDPMT22EG/ziggutwist-too . Ziggutwist Too is a take-apart version of Ziggutwist, both binary puzzles inspired by Bram Cohen's Ziggurat puzzle. The puzzle has six rotating piece with an arrow. They start all pointing north. The object is to make them all point south west. What makes Ziggutwist (and Ziggurat) special is that they are "metronome-less". Regular N-ary puzzles have a piece that acts as a metronome. Every other move is the metronome, which signals which piece should be moved next. Ziggu puzzles don't have such metronome, which makes their design simpler. Whenall arrows are pointing south-west, the pieces can be slid out from the frame.
Copyright (c) 2024, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and https://www.sloyd.fi/brain-teasers/inventors-designers/oskar-van-deventer (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleZiggutwist - How can this puzzle be made more meaningful?OskarPuzzle2024-05-04 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/ziggutwist or shapeways.com/product/8XFBJE4GB/ziggutwist . Ziggutwist is a binary puzzle, inspired by Bram Cohen's Ziggurat puzzle. The puzzle has six rotating piece with an arrow. They start all pointing north. The object is to make them all point south west. What makes Ziggutwist (and Ziggurat) special is that they are "metronome-less". Regular N-ary puzzles have a piece that acts as a metronome. Every other move is the metronome, which signals which piece should be moved next. Ziggu puzzles don't have such metronome, which makes their design simpler.
Copyright (c) 2024, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and https://www.sloyd.fi/brain-teasers/inventors-designers/oskar-van-deventer (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleZigguhooked - How addictive is this puzzle?OskarPuzzle2024-04-27 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/zigguhooked or shapeways.com/product/3JN2EQ93V/zigguhooked . Zigguhooked is a binary puzzle inspired by Bram Cohen's Ziggurat puzzle. The puzzle has six rotating piece with an arrow that are hooked together and to the board. When all unhooked, the slider with rotating pieces can slide out of the frame. This puzzle is yet another attempt to create a 2D rotational n-ary puzzle, similar to Zigguflat, but then rotating instead of sliding.
Copyright (c) 2024, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and https://www.sloyd.fi/brain-teasers/inventors-designers/oskar-van-deventer (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleZigguchain - Is this the worlds most simplistic binary puzzle?OskarPuzzle2024-04-20 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at puzzleguystore.etsy.com/listing/1657301502/zigguchain-puzzle-designed-by-oskar-van or https://i.materialise.com/en/shop/item/zigguchain or shapeways.com/product/PXM62F369/zigguchain . Zigguchain is a binary puzzle, inspired by Bram Cohen's Ziggurat puzzle. The puzzle has six identical rings that are linked together into a chain. When together, all notches in the ring point sideways. The object is to take the chain apart. As the puzzle is binary, each additional ring takes about twice as many moves, so 64 moves for six rings. What makes Zigguchain (and Ziggurat) special is that they are "frame-less". Regular N-ary puzzles have a frame against which the pieces rotate or slide. This puzzle doesn't have a frame, as the adjacent rings keep all rings in place. Zigguchain may be the world's most simplistic binary puzzle.
Copyright (c) 2024, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and https://www.sloyd.fi/brain-teasers/inventors-designers/oskar-van-deventer (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleDominumbers - How can you count with magnetic e-ink?OskarPuzzle2024-04-13 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/dominumbers or shapeways.com/product/7A39MKP22/dominumbers . Dominumbers is a pattern puzzle with magnetic marbles and a magnetic board. The object of the puzzle is to place the domino pieces such that they make numbers: 0123456789. Other challenges are +-*/:|^║=?, white and black. The puzzle is quite confusing to solve, if you don't know what you are doing. When solving systematically, one would first need to map out the magnets embedded in the board and in the seven pieces. With that knowledge, one can easily solve each challenge on paper, and then confirm with the magnetic puzzle.
The puzzle was designed by using Excel. 15 magnets are placed in the board randomly, and it counted the number of black-white (and white-black) spheres for each of the challenges. If all those numbers are equal, then the puzzle can at least be solved with monominoes. If not, then the loop is repeated. Excel found a solution quickly. Surprisingly, that solution did not only allow the ten canonical challenges 0123456789, but over ten additional challenges. So the magnet placement on the board is quite "universal". Next, I combined the 15 monominoes into 6 dominoes (two of each of the three types 00, 01, 11) and one triomino (the "V" triomino, 110). After that, I manually confirmed that each of the twenty challenges are solvable.
Copyright (c) 2024, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and https://www.sloyd.fi/brain-teasers/inventors-designers/oskar-van-deventer (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzlePentomiyes - Can you turn this no into a yes?OskarPuzzle2024-04-06 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/pentominyes or shapeways.com/product/D67SVQ7BU/pentominyes . Pentomiyes is a pattern puzzle with magnetic marbles and a magnetic board. The object of the puzzle is to place the pentomino pieces such that they spell NO. The second challenge is to make them spell YES. That is, from "pentomino" to "pentomiyes".
A whopping 55 magnets were embedded in the board during 3D-printing, with specific up-down (north-south) orientations. Another 55 magnets were glued into the black-white marbles. These 55 magnetic marbles were glued into 11 white domino pieces. The puzzle was designed by asking Burrtools for two random 5x11 pentomino designs. Next I used Excel to keep administrative track of which square moves where, when going from NO to YES. By rotating and flipping some of the symmetric pieces, I found a consistent magnet placement. Note that the puzzle has a parity challenge. Whenever two balls are swapped, then either both change color, or neither. Therefore, NO is spelled at the front side of the board, and YES at the back side.
Copyright (c) 2024, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and https://www.sloyd.fi/brain-teasers/inventors-designers/oskar-van-deventer (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleE-Ink Puzzle - How to develop more challenges for this puzzle?OskarPuzzle2024-04-01 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/e-ink-puzzle or at shapeways.com/product/SFRSFSCA5/e-ink-puzzle E-Ink Puzzle is a packing problem, where the goal is to pack the seven Tetris-style pieces onto a 5x5 board. The pieces have little black-and-white balls with magnets. The board also has magnets, which orients any magnetic ball that is placed on top. The goal is to make a black 5x3 digit "0", with all the other balls white. The puzzle is pleasant to play, as the magnets keep the pieces in place on the board. It is also quite satisfying, and confusing, to see the color changes when sliding the puzzle over the board.
According to a Burrtools analysis, there are 111 different ways to place the seven pieces in a 5x5 grid. This number should be multiplied by 16 because of asymmetry of the board: 4x rotations, 2x front-back, 2x mirror image. So the puzzle may be much harder than it looks like.
A meta-challenge for this puzzle is to design the magnet placement in the pieces and the board such that there are multiple nice pattern challenges, not just the present "0". There are theoretically 2^50/16-or-so different possible placements of the magnets, too many to reasonable analyse with a computer. Also, it can be reasoned that even having two specific challenges (e.g. "0" and "1") may be impossible with those 50 magnets. So, we need to accept to have only this single challenge.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleCave Man Puzzle - How to get the caveman out of his mancave?OskarPuzzle2024-03-23 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/cave-man or at shapeways.com/product/ZGGFGEAA5/cave-man Cave Man was designed 8 June 1987, and first built in wood by Jean Carle and later by Tom Lensch. The puzzle is no longer available in wood, but now as 3D-print. The object is to remove the man from his cave. The puzzle is effectively a maze in a 3x3x3 cube, possibly the most complex maze in such a little space.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleOskars Two Piece Packing - What is the maximum number of moves with a 4x4x4 cube?OskarPuzzle2024-03-17 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/oskar-s-two-piece-packing or at shapeways.com/product/SMEWYMGY8/oskar-s-two-piece-packing Oskar's Two-Piece Packing Puzzle dates back to the 1980's, but the design drawing could not be located. This puzzle was originally made in wood by Tom Lensch, and now available for 3D-printing. The object of the puzzle is to packing the two pieces into the box with a significant number of moves. Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleNEWS Gears - What is NEWSworthy about these gears?OskarPuzzle2024-03-09 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/news-gears or at shapeways.com/product/GJDPZPC26/news-gears NEWS Gears was a design challenge by Pantazis Houlis, after seeing my Traffic Light Gears (twistypuzzles.com/forum/viewtopic.php?p=425650#p425650 ): "... maybe use a slightly more complex version to show the wind direction? I.e. instead of colors to have N,W,E,S". This is the result. When the blue arrow is turned, the black circle moves North-East-South-West. The rotation speed of the black gear is three times the turning speed of the blue arrow. The black circle moves along a cycloid path, briefly pausing at each of the four wind directions. Based on the motion of the black gear, the red and green gears at the front were "rolled off". Next, the gears at the back were designed to match the required rotation accelerations and decelerations of those red and green front gears. As before, this gear system is the solution to a design puzzle, and it has no known application otherwise.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleGalactic Gears - Is the red gear exactly elliptic, or does it only look that way?OskarPuzzle2024-03-02 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/galactic-gears or at shapeways.com/product/X2BKVMVNL/galactic-gears Galactic Gears is a gearing system with oddly-shaped gears. The little yellow gear is circling the little blue gear like a planetary gear. The big red gear was formed by "unrolling" the big yellow gear. The green and smaller red gear are shaped by the relative motion of the other gears. As usual, the puzzle here was the design challenge to make a gear system with these "galactic-gearing" properties. There are no known applications.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleDiskussion - What makes the little disks automatically move from one dial to the next?OskarPuzzle2024-02-17 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/diskussion or at shapeways.com/product/CL88JMKJM/diskussion Diskussion is a magnetic sequential-movement puzzle. The tokens are 12x3-millimeter magnetic disks. There are also five magnets embedded in the frame. When one of the four rotors is turned such that the void goes over an embedded magnet, then the adjacent magnetic token will jump into the void. So the puzzle is played by only turning the rotors without touching the tokens. The one-way jumps of the tokens make it impossible to simply "undo" a wrong move. Nevertheless, the puzzle is relatively easy to solve.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleHeart too Heart - Is it too cute?OskarPuzzle2024-02-10 | This is a Valentine's-Day-themed version of the Heart-to-Heart gear toy. Two geared hearts roll perfectly around each other. There is a round space to put photos of yourself and your loved one.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzlePRBS Generator - What are Pseudo-Random Binary Sequences used for?OskarPuzzle2024-02-03 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/prbs-generator or at shapeways.com/product/2AV7JT5GN/prbs-generator PRBS Generator is a piece of kinetic art that mechanically generates a Pseudo-Random Binary Sequence (PRBS, en.wikipedia.org/wiki/Pseudorandom_binary_sequence ). When I learned about PRBS at my university, I designed a mechanism for it on 10 January 1987. The mechanism was as simple as the algorithm to generate a PRBS. It uses a shift register, where a new bit is the exclusive OR (XOR) of two earlier bits. I implemented this mechanism 37 years later, where the shift register is a set of seven "bits" on a rotating disk. At one point, a bit flips when its neighbour is "0", whereas it stays the same when the neighbour is "1". The flipping is pushed by gears at the bottom of a bit. The flipping is blocked when the neighbour is in its "1" state. Then the magnets decouple the rotation of the gear from the bit. The mechanism cycles through 127 different seven-bit sequences, only skipping the "1111111" sequence.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleNobbz - Would this make a good 60-challenges puzzle?OskarPuzzle2024-01-20 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Read more at twistypuzzles.com/forum/viewtopic.php?t=39190 Nobbz is a multi-challenge gearing puzzle, inspired by Joe Becker's Gearloose puzzle from the year 2000. Each challenge places some of the gears onto the 3x3 grid in a random orientation. The object of the puzzle is to rotate the gears such that the arrows all point in the same direction. The gears have missing teeth, which allows you to skip teeth at some places. The challenge is to find out where to skip teeth, and in which direction. There are two versions of the Nobbz puzzle. The first version uses the same pointy gears as Screw Gears ( youtube.com/watch?v=pD7pk4LLfp8 ). This is the harder version, as the gap also blocks gear rotation, which limits the skipping of teeth. Nobbz Too uses gears closer to those from Joe Becker. Here, the puzzle difficulty increases much slower with the number of gears in a challenge.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleA Gearus Line - Can you make this line of gears spin in sync?OskarPuzzle2024-01-13 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/a-gearus-line or at shapeways.com/product/SRTWZ2A3X/a-gearus-line A Gearus Line is a gear-matching puzzle. The object is to place the six oddly-shaped gears over the four diamond-shaped shafts such that they rotate freely. When gears are placed incorrectly, then the final gear won't fit, or the rotation will block. The number of combinations may seem huge. However, some clever thinking can reduce this number significantly. The net acceleration of the three gear pairs should be zero, as the red shaft spins at the same speed as the light-green one. So any acceleration from one or two gear pairs should be compensated by the third pair.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleGear Fit - How would you approach solving this puzzle?OskarPuzzle2024-01-06 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/gear-fit or at shapeways.com/product/48PKRYTAR/gear-fit Gear Fit is a gear-matching puzzle. The object is to place the two oddly-shaped gears over the two seven-pointed-star shafts such that they rotate freely. When gears are placed incorrectly, they won't fit, or the rotation will block. Hidden inside the frame is an identical set of gears that control the rotation of the shaft. The system will turn only when the placed gears match the hidden ones.
When one naively tries tries all possible combinations, then this may take up to 7x7x8=392 attempts. However, when you realise that the placement of one gear determines the other, then only 7x4=28 attempts remain. One can reduce this number even further, when checking at which orientation one shaft turns the fastest, and what this means for the orientation of the gears. Hence, this puzzle is quite solvable with some clever thinking.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleDouble Fractional Gears - How can objects have fractional rotation symmetry anyway?OskarPuzzle2023-12-30 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/double-fractional-gears or at shapeways.com/product/H8FZS7PNB/double-fractional-gears Double Fractional Gears is a spin-off of my Fractional Gears. Whereas the latter features a gear with "half-fold symmetry", this gear system also features a gear with "third-fold symmetry". That gear needs to complete three full turns (1080 degrees) for the gear system to get back to its starting position. So the gear system as a whole has a half:third gearing ratio at average. It was quite a challenge to develop this gear system, with six virtual prototypes and two 3D-printed ones. The biggest problem was to prevent the gears from bumping into each other. The gear-on-gear approach of Fractional Gears did not work. The working solution was to have the teeth spiral around their axle two or three times.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleSpinor Gears - How does this 720-degrees rotation symmetry relate to quantum mechanics?OskarPuzzle2023-12-23 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/spinor-gears or at shapeways.com/product/MBPD66C8R/spinor-gears Spinor Gears are a response to Bram Cohen's challenge when he saw my Fractional Gears ( youtube.com/watch?v=o3qke3brdn8 ), which features one gear with "half-fold" rotational symmetry. The question was whether it would be possible to design a gearing system with two identical half-fold gears, where the system returns to its starting state after 720 degrees of rotation, instead of the usual 360 degrees. The answer to the question is "no", as illustrated by the prototype. Even though the gears can rotate by more than 620 degrees, by far exceeding the 360-degrees mark, 720 degrees is not possible. The problem is that there will always be a "cross-over point", where there is ambiguity in which "track" the gear set is, and hence teeth bump into each other.
The second prototype follows the adage "fake it, if you can't make it". The yellow stand contains a hidden gearbox that simulates the desired 720-degrees behaviour. Some teeth of the gears were cut off, in order to allow the gear set to pass through the cross-over point.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleHerons Super Fountain - How can this gravity-driven fountain sprout higher than itself?OskarPuzzle2023-12-02 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Heron's Super Fountain is a new take on the classic Heron's Fountain ( en.wikipedia.org/wiki/Heron%27s_fountain ), which is a hydraulic machine invented by the 1st century AD inventor, mathematician, and physicist Hero of Alexandria. A limitation of the Heron's Fountain is that the fountain height is limited by the height of the set-up. Heron's Super Fountain overcomes this limitation by cascading four container pairs in a row. Each pair adds to the water pressure proportional to the difference of the water levels. As a result, the fountain can shoot to more than double the height of the system itself.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleOskars Matchboxes Puzzle - Are you 3D-printing this, or glue this puzzle from regular matchboxes?OskarPuzzle2023-11-25 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at kubekings.com/rompecabezas-de-plastico/matchbox-puzzles-de-ingenio.html , https://i.materialise.com/en/shop/item/oskar-s-matchboxes or at shapeways.com/product/8DJWCJ9W3/oskar-s-matchboxes . Oskar's Matchboxes has become a classic do-it-yourself puzzle. Glue the matchbox drawers to five matchbox sleeves, and then try to close all matchboxes. This is the first Oskar puzzle that got wide publicity, starting with publication in a Dutch newspaper in 1983, and subsequently in many do-it-yourself books. Nowadays with 3D-printers, you can also 3D-print the puzzle yourself. Glue is needed to glue the parts together. My glue of choice is is transparent two-component epoxy glue (Bison Kombi).
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleRhombox - Can you prove that this puzzle box has a unique solution?OskarPuzzle2023-11-18 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/rhombox or at shapeways.com/product/EPCWF75FS/rhombox Rhombox is an assembly puzzle. The object is to build a rhombic dodecahedron from the twelve panels. The puzzle was designed in 1983. Several versions have been made in wood and metal. The puzzle has four types of pieces and it has a unique solution.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleOskars Magic Box - Would this be a good box to hide treasure?OskarPuzzle2023-11-11 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/oskar-s-magic-box or at shapeways.com/product/95MH8N5Y2/oskar-s-magic-box. Oskar's Magic Box is a nice beginner puzzle, invented in 1983. The object is to put the six pieces together and form a box. The puzzle has the doubtful honor to be Oskar's first design that got knocked off. The knock-off was produced by Robert Dalloz and sold by Arjeu in the 1980's.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleSliding Soma - How to get the Soma pieces into THIS box?OskarPuzzle2023-11-04 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/sliding-soma or at shapeways.com/product/DMD2XUKN5/sliding-soma Sliding Soma is an invention by Volker Latussek. The object is to place the seven Soma Pieces into the closed cage. The cage can slide open, but only to a point. So many of the pieces can go in after some rotations and other manipulations. Fun puzzle to solve.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleTraffic Light Gears - Would you wait for the gears to turn green?OskarPuzzle2023-10-21 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/traffic-light-gears or at shapeways.com/product/6QC9LVHSU/traffic-light-gears Traffic Light Gears is a gear-design challenge, both posed and solved by Oskar. The object was to have a little circular gear move between three positions above each other, and stop for a little while at each of the three positions. The three positions are marked "green", "orange" and "red", after the colors of Dutch traffic lights. The solution is two big "pentagonal" gears at the front, and another three at the back. The gears are precisely shaped and dimensioned to have the little black gear move straight up and down. And like any traffic light, the pause at orange is only brief.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleFractional Gears - How can a gear have half-fold rotational symmetry?OskarPuzzle2023-10-14 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/fractional-gears or at shapeways.com/product/AC524R66H/fractional-gears Fractional Gears is a gear set that features a gear with "half-fold" rotational symmetry. A gear with 180-degrees symmetry is said to have "two-fold" rotational symmetry. The green egg-shaped gear has 360-degrees "one-fold" symmetry. For a 360-degrees turn of the green egg-shaped gear, the smaller red gear rotates by 720 degrees. Following the earlier naming logic, this gear has half-fold rotational symmetry.
In order to make the cardioid-like gearing, the red gear has two layers. The teeth pattern continues from the bottom layer to the top and back to the bottom. In order to fit the bigger red bottom, the green gear has a cut out to make things fit.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleDerailed Hearts - Can you get these gears back on track?OskarPuzzle2023-10-07 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/derailed-hearts or at shapeways.com/product/KRUMTABYQ Derailed Hearts is a gearing mechanism, where the green and red heart-shaped gears roll over a yellow rack gear. Despite the odd shapes of the gears and rack, the blue connecting rod slides in a perfect straight line. The red and green gears have the same shape, and are exact mirror images. This was achieved by giving the yellow rack a slide-mirror symmetry. Learn more "How to Design a Wheel That Rolls Smoothly Around Any Given Shape" from this video ( youtube.com/watch?v=ZWWgGk9JU0E ) by Morphocular.
Even though the gearing mechanism is not a puzzle, it may feel like one. If one derails the gears, it takes some conscious effort to find out from which side the rack should be inserted between the gears, and at what orientation of the gears.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleRolling Hearts - What other kinetic gear art can you make with Gearify?OskarPuzzle2023-10-01 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/rolling-hearts or at shapeways.com/product/QTBYEZZEC/rolling-hearts. Rolling Hearts was designed with the Gearify v2 software by Michael Valle (gearifysoftware.com ). I was invited as beta tester of new version 2, which supports involute gears. I started with a heart shape, and let Gearify calculate some companion shapes with 1, 2 and 4-fold symmetry. I combined these into an S-shape. The little gears, with all colors of the rainbow, roll around the irregular S-shape.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleWobbly Planets - How come that these gears fit so perfectly?OskarPuzzle2023-09-23 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/wobbly-planets or at shapeways.com/product/QAXEQPPEZ/wobbly-planets Wobbly Planets was designed with the Gearify v2 software by Michael Valle ( gearifysoftware.com ). I was invited as beta tester of new version 2, which supports involute gears. This planetary gear system has three elliptical planet gears, an elongated sun gear with twofold symmetry, and a pentagram-like annulus. It is a fidget toy. Its purpose to turn it endlessly and to stay mesmerized.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleHeart to Heart - Wouldnt this make a cute doodle toy?OskarPuzzle2023-09-10 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/heart-to-heart or at shapeways.com/product/DNUHXQSS6/heart-to-heart Heart-to-Heart was designed with the Gearify v2 software by Michael Valle ( gearifysoftware.com ). I was invited as beta tester of new version 2, which supports involute gears. I started with a heart shape, and let gearify calculate its companion. I took the average of the two shape, and repeated the process a few times. The results is two nearly-mirror-identical heart shapes that roll around each other. It is a fidget toy. Its purpose to roll it endlessly and to stay mesmerized.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleEinstein Tiling Puzzle - What is the one stone that rules them all?OskarPuzzle2023-09-03 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/einstein-tiling-puzzle or at shapeways.com/product/N88R6HSE3/einstein-tiling-puzzle. Einstein Tiling Puzzle is based on the famous aperiodic tiling pattern, discovered by David Smith and mathematically proven by Joseph Samuel Myers, Craig S. Kaplan, and Chaim Goodman-Strauss. As described by the authors, the "Einstein's Hat" tiling is one tiling from a continuum, starting from an arrow tiling. My idea was to turn this into a tiling puzzle by having 3D pieces that layer-by-layer morph from arrow to hat. Craig Kaplan provided me with the 2D curves to CAD this morphing. Craig observed that the pieces shift from position during the morphing, and hence all pieces would be different. This makes the resulting puzzle rather difficult to solve.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleSound Patterns - Can you further optimise this puzzle design?OskarPuzzle2023-08-26 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/sound-patterns or at shapeways.com/product/2KBUJ8Y2Z/sound-patterns. Sound Patterns is a tribute to the work of Kagen Sound. Kagen developed a series of (award-winning) secret opening boxes that require to form a specific mesmerizing maze-like pattern. In this new puzzle, Kagen's pattern is applied to small rings along a tall cylinder. The object is again to make a set of symmetrical patterns. This is challenging, because each ring has a little knob at the inside, which slides into notches in the cylinder. Each rings fit on multiple places around the cylinder, but not everywhere. The notches pattern was designed such that there is only a single solution for each of the seven challenges. The puzzle is a bit confusing, but not too hard to solve. And the results are very satisfying.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleZero Knowledge Puzzle - How to prove your knowledge without telling the secret?OskarPuzzle2023-08-19 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. See also twistypuzzles.com/forum/viewtopic.php?t=38840 --- Alice and Bob enter a room. They see four purple tiles on the table with black letters, “ZKP”. Alice: “Those four tiles look identical to me.” Bob: “No they are not. One pair looks different from the other pair.”
Puzzle #1 How can Bob prove to Alice that he can distinguish the pairs, without Alice learning which tiles goes with which?
Carol enters the room, and joins Alice and Bob. Alice: “Carol, what do you think, do these four tiles look identical?” Carol: “No they are not. One pair looks different from the other pair.” Bob: “That is what I said!”
Puzzle #2 How can Alice find out whether Carol and Bob have identified the same pairs as belonging together, without Alice learning which tiles goes with which, and without Bob or Carol learning whether the answer is “yes” or “no”?
Obviously, the puzzles are to find appropriate zero-knowledge proofs that can provide statistical (99.99%) certainty that Alice gets correct answers. You can use envelopes and markers. Please use the markers only on the envelopes, not on the tiles. Feel free to put envelopes into envelopes.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleHerons Fountain - Will you print it yourself? https://oskarvandeventer.nl/Print-It-Yourself/OskarPuzzle2023-08-12 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. #shorts Heron's Fountain is a classic water ornament, powered by gravity. The water is pushed out by air pressure from water leaving the top container and going into the bottom one. This version is 3D-printed as one single piece. Will you 3D-print one on your own 3D-printer?
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzlePlunging Piston - Did the innuendo warning effectively refrain you from watching this video?OskarPuzzle2023-08-04 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Plunging Piston is a take-apart puzzle. The 69-gram pink piston is inserted into the beige hole, where it locks in place in a mechanism that uses magnets and metal balls. One cannot directly pull out the piston. However, the balls run in a groove pattern that make the mechanism operate like a counter. When the in-and-out motion is repeated eight times, then the piston can be pulled out.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleMarble Castle - How does one design such marble track?OskarPuzzle2023-07-29 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy the miniature version at https://i.materialise.com/en/shop/item/marble-castle-miniature or at shapeways.com/product/DUU95V7W9/marble-castle-miniature. Marble Castle is a 3D-printed marble track. The ball runs from the top center all the way down, over the castle wall, into the back gate and out through the front gate. One can roll a 7-millimeter steel ball inside the track, or a 10-millimeter steel ball over de edges of the track. This big version took over 78 hours (more than 3 days) to print. It used 234 meter (700 gram) of filament. I used rainbow filament for the castle, and tri-color co-extruded filament for the bottom layer. The castle is 178x199x212 millimeter.
Notice the question-mark-shaped start of the track at the center. This is a tribute to Adrian Fisher, who uses this feature in several of his maze.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleOskars Mug - Can you drink from this without spilling all over yourself?OskarPuzzle2023-07-22 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at kubekings.com/rompecabezas-de-plastico/oskar-s-mug.html or at etsy.com/listing/1570458430/oskars-mug .View photos at twistypuzzles.com/forum/viewtopic.php?t=38787. Oskar's Mug is a puzzle mug. The object is to drink from the mug. However, the mug has holes at its sides, such that tilting the mug results in spilling your drink. The solution is in the small holes at the rim. One of them acts as a straw to drink from, sucking the liquid out. Two other holes need to be kept closed, on at the bottom, one in the handle, so you don't suck in air. When you stop drinking, then there is another surprise. Due to the siphon effect, liquid will keep spilling from bottom hole that you kept closed for air. To stop the spilling, you need to blow air in the opposite direction and break the siphon effect. This puzzle combines a classic puzzle jug (en.wikipedia.org/wiki/Puzzle_jug) with a classic greedy cup (en.wikipedia.org/wiki/Pythagorean_cup).
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleCliff Hanger 3D printed - Can you balance this piece over an edge?OskarPuzzle2023-07-15 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Cliff Hanger is a true one-piece puzzle. The object of the puzzle is to hang it over a sharp edge of a table, such that it keeps hanging. A heavy piece of steel inside the puzzle shifts it center of gravity. Because of that weight, there is only a single solution. Original prototypes of this puzzle were made in cardboard and veneer. This 3D-printed version was made in birch filament.
The weight for this puzzle is a 2.54-mm diameter 80-mm length steel rod, weighting 313 gram. The two birch parts plus alignments screws weight together 235 gram. Make sure to set the infill density and wall thickness such that it makes the weights precisely, otherwise the puzzle will have multiple solutions, or none.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleWater Castle - Did you notice the question mark?OskarPuzzle2023-07-09 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/water-castle or at shapeways.com/product/QMTSTC7E5/water-castle Water Castle is a water ornament. A water pump gets the water to the castle tower. From there, the water zigzags down along the castle walls all the way out through the gate. A subtle detail of Water Castle is the little question mark, which are the top 9 towers through which the water flows. This is a little tribute to the landscape maze designs by Adrian Fisher, who uses this question mark in his maze logo.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleMysterians - ??? What makes this puzzle so mysterious ???OskarPuzzle2023-07-01 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/mysterians or at shapeways.com/product/RYUVW5CGF/mysterians Mysterians is a three-layer disassembly puzzle. The three layers rotate and slide over each other in a sensual way, until they can be taken apart. The three plates look like question marks. Nick Baxter named this puzzle Mysterian. Solving the puzzle is like solving a labyrinth, moving from turn to turn. Surprisingly, this "maze" has no loop or dead ends, it is 100% unicursal. Nevertheless, people get confused at some point and start going in the opposite direction, ending up at the start. This puzzle is proof that people can get lost in a Belgian maze.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleTetra Flop - How many puzzle awards has Volker Latussek already won?OskarPuzzle2023-06-17 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/tetra-flop or at shapeways.com/product/RCSF9KDLH/tetra-flop Tetra Flop is yet another packing problem by Volker Latussek. The object is to pack the eight tetromino pieces into a 2x4x4 cage. The hole was designed to allow only the intended solution, while blocking any near-miss solutions. A second smaller hole in the bottom assures the chirality of the solution. Obviously, the solution requires many rotations.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleOskars Cube 3.5x3.5x3.5 - Why the three-and-a-half?OskarPuzzle2023-06-11 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/oskar-s-cube-3-5x3-5x3 or at shapeways.com/product/AJJZSDFWM/oskar-s-cube-3-5x3-5x3-5 Oskar's Cube, the original 5x5x5 version was designed 11 November 1984. The concept was published in Scientific American in 1988. A plastic version was brought to market in 1992 by an Australian company. A few years later, Bits and Pieces made a metal version. This version was designed in around 1994, and first prototyped in wood by Jerry McFarland. The object of the puzzle is to move the cross through the three maze from the square to the dot.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleOskar Key - When did Hanayama first produce this puzzle?OskarPuzzle2023-06-03 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at kubekings.com/rompecabezas-de-plastico/oskar-key.html , https://i.materialise.com/en/shop/item/oskar-key or at shapeways.com/product/RQ6X2LA88/oskar-key . Oskar Key was originally designed in 1987, based on an idea from 1984. This two-layer puzzle key was mass-produced in metal by the Japanese Hanayama toy company. It was the very first licensed design by Hanayama. Production has stopped a long time ago, and vintage samples are occasionally sold at Ebay for 1000 USD. Several people asked me for a 3D-printable sample, so here it is. To make the puzzle even more challenging, I added a third key in the middle. The underlying mathematical concept is Prof. N.G. de Bruijn's Beer Bottle Problem (see vixra.org/pdf/1208.0223v1.pdf, page 110), who proved in the 1960's (?) that such puzzle is always solvable.
Copyright (c) 2023, M. Oskar van Deventer.
Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at puzzlemaster.ca/browse/inventors/oskar (USA, CA) and http://www.sloyd.fi/oskar-deventer-c-151_154.html (EU) Buy exclusive 3D-printed Oskar puzzles at http://shapeways.com/shops/oskarpuzzles and https://i.materialise.com/shop/designer/oskarpuzzleUnfolded Flop - How do you like these Volker Latussek inventions?OskarPuzzle2023-05-27 | Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/unfolded-flop or at shapeways.com/product/4656RXKFQ/unfolded-flop Unfolded Flop was invented by Volker Latussek. The object is to put the seven pieces into the cage. The set is almost the Soma set, but the V piece is replaced with the three-cubie I piece) The cage is designed such that only one solution is possible, and that all near-miss solutions are prevented. Obviously, lots of rotations are needed.