Third Build
3
Construction of the hardware is almost complete. Computer control is complete on paper...must make a PCB and test it. Then programming.
The white pieces have magnets with their North poles facing the bottom, the brown pieces have South poles facing down. A change of current flow direction in the electromagnet (EM) will change polarity of the EM to keep the EM opposite polarity of the magnet, to allow attraction.
I had to get new 2040 V-rail and new linear rails to accommodate the larger layout due to adding an area for captured pieces. (Notice I don't use the common term, MEN...). I only have room for 16 pieces that will be put there by the Phantom, no room for the other 16. Maybe the game will be over by then...
I did not enclose this version in a box because this makes it hard to work on, so I used a wood base with 1/4" bolts rising from it to hold the top board which will have the checker layout on the top side with the printed circuit boards with Hall effect switches on the underside. I will sandwich these boards between two sheets of acrylic plastic.
I had to get new 2040 V-rail and new linear rails to accommodate the larger layout due to adding an area for captured pieces. (Notice I don't use the common term, MEN...). I only have room for 16 pieces that will be put there by the Phantom, no room for the other 16. Maybe the game will be over by then...
I did not enclose this version in a box because this makes it hard to work on, so I used a wood base with 1/4" bolts rising from it to hold the top board which will have the checker layout on the top side with the printed circuit boards with Hall effect switches on the underside. I will sandwich these boards between two sheets of acrylic plastic.
Because of the way the Hall switch is oriented, the south pole is facing upwards out of the PCB, or in other words towards the player on the other side of the plastic cover.
The "values" in the table below represent a full scale 10 bits on the analog input of the MCU, from 0 to 1023. This is a example only, not the final values used in the project.
The electromagnet will have to switch polarity for the brown or white players, so an H-bridge circuit is being used to accomplish this.
The "values" in the table below represent a full scale 10 bits on the analog input of the MCU, from 0 to 1023. This is a example only, not the final values used in the project.
The electromagnet will have to switch polarity for the brown or white players, so an H-bridge circuit is being used to accomplish this.
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I swapped out the reed switches for Hall effect linear sensors
Each side, white or brown has different polarity magnets
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Electromagnet changes polarity so that it doesn't repel the same polarity magnet. when it selects a piece to move it.
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New layout accommodates space for captured pieces
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No box this time, open build
New plastic pieces designed for x-y trolley and 3D printed
Printed own chess set with consistent base diameters
X-Y Trolley
Magnet Testing
Electronics
Because of anticipated speed and memory requirements, I replaced the Nano as specified in original plan with an ESP32 WROOM MCU and designed a PCB that was better thought out than previous. The ESP32 has a number (6) of pins NOT AVAILABLE for use due to them being used for flash memory. (My question: why have the pins there then, if they can't be used?)
Summary:
Copyright 2024 Queenidog - All Rights Reserved
This set of pieces was replaced with my own 3D printed set in order to get consistent and similar-in-diameter bases. See photo gallery after this one.
The old wood sets of chess pieces were out-of-round and had different diameters, depending on the piece. For the Phantom to work, he has to move pieces between other pieces (since he can't pick them up) and if there is magnetic attraction or repulsion between the pieces, well, this is not good. He has to pick ONE piece, no more.
Material such as Permalloy or Mu-metal can protect items from magnetic fields but a simpler idea is the use of ferro-magnetic material like soft steel. ("Ferro" means can be magnetized). So I came up with the idea of cutting rings out of a piece of electrical conduit. My first test, as shown in photo below was with a magnet surrounded by a large metal nut.
Because of the limitations of the wood pieces, I printed the set shown below after modifying the 3 dimensions, and adding an 8x3 mm hole in the base for a magnet. Since I had done this before coming up with the ring idea, I didn't want to reprint the entire set again so I made 5mm high pedestals (see photo below) that I glued on with crazy glue. The metal rings fit around these. The first photo in the gallery below shows the complete set with rings and magnets. Hover over photo for description.
Material such as Permalloy or Mu-metal can protect items from magnetic fields but a simpler idea is the use of ferro-magnetic material like soft steel. ("Ferro" means can be magnetized). So I came up with the idea of cutting rings out of a piece of electrical conduit. My first test, as shown in photo below was with a magnet surrounded by a large metal nut.
Because of the limitations of the wood pieces, I printed the set shown below after modifying the 3 dimensions, and adding an 8x3 mm hole in the base for a magnet. Since I had done this before coming up with the ring idea, I didn't want to reprint the entire set again so I made 5mm high pedestals (see photo below) that I glued on with crazy glue. The metal rings fit around these. The first photo in the gallery below shows the complete set with rings and magnets. Hover over photo for description.
Obsolete
As-Built
Hover over any image to get a description
However...after breadboarding the ESP32, it soon became apparent that the pins I had chosen for various functions did NOT have pull-up resistors internally which makes it messy to have them externally. I also ran out of pins, using all of the available ones (note above), so I decided to swap out the MCU AGAIN. Go to FOURTH BUILD
