Now we've tested our capacitive sensing board and everything appears to work when using pennies (and batteries) as playing pieces. The next thing we need to know - before getting immersed in board builds, data manipulation etc - is that the whole concept still works if we use anything other than pennies or batteries.
This project started out as a digital Blood Bowl game board but we've come to realise that it has potential to be used to "electronify" (is there such a word?) many other popular board games. Luckily, many of the miniature playing pieces used in these types of games are metallic (pewter). All we need to do is make sure the metal figurine is connected to a penny in the base of the miniature.
The "slotta-bases" used by many miniature manufacturers are ideal for this.
Remove some of the plastic from the underside of the slottabase and file the bottom of the figurine so that there is enough space under the miniature for our penny
The finished model should look exactly as before, only with a void under the base to house our penny. When the finished figurine is placed over the penny, an electrical connection is made from the coin to the miniature but the penny is not visible:
This means that touching the miniature gives the same result as touching the penny - i.e. we can, indeed, use a metal miniature as a playing piece on our capacitive sensing game board:
Note that the flickering LED in the demo is not due to a fault in the board - trying to watch the video viewfinder and place the piece on the correct place on the board meant sometimes it sat between pads