Reaction Game Tables
For our recent visit to the Raspberry Pi 5th birthday party we wanted to take along a few fun demonstration items to help show off the incredible versatility of the amazing Raspberry Pi. One of the items we took along was our Raspberry Pi controlled Makerspace CPC crane which proved to be a great success. We also wanted to take along a fun game for our fellow Pi party people, so we came up with the idea of a 2 player reaction game with a slight twist.
Bare Conductive Pi CAP
Our reaction game tables are based on the Bare Conductive Pi CAP board, which is a capacitive touch board that sits on top of a Raspberry Pi.
The Pi CAP has 12 capacitive touch electrodes, which can be connected to all manner of different things such as fruit, jelly babies, conductive paint, and generally anything that can conduct small amounts of electric current.
For the purposes of our reaction game, we decided that we would use aluminium foil tape connected to the Pi CAP by means of short wires. The foil tape would be laid out to form small pads on our tables, over which we could lay a vinyl cut overlay of our own design.
For our tables we enlisted the assistance of our ever helpful handymen Steve and John, who put together 2 excellent wooden tables about 80cm tall and 50cm x 50cm across. Fellow Makerspace crew member ItsAll_GeekToMe provided 2 custom made vinyl cut Makerspace logos of the right size to fit on top of the tables, and holes were drilled through the top of the table to allow 12mm M6 countersunk machine screws to be passed through the table top.
Our aluminium foil was then stuck to the table to match the cut outs in the vinyl overlays, and the M6 countersunk machine screws were passed through the foil pads. We then stuck another layer of the aluminium foil tape over the top of the foil pads in order to obscure the heads of the screws. There are 6 pads on each table. To connect the screws to the Pi CAP we used 0.2mm copper wire onto which we soldered M6 solder lugs at one end. These solder lugs were then attached to the M6 machine screws using M6 lock nuts.
The final finishing touch for the tables was then to stick the vinyl cut overlays onto the tables.
Attaching the Raspberry Pi
To attach the Raspberry Pi to one of the tables, we used a base of an old Raspberry Pi case onto which we screwed 4 M2.5 10mm brass standoffs. The base of the Pi case was then screwed to the underside of one of the tables using short wood screws, and the Raspberry Pi was then screwed on to the standoffs.
Pi CAP Connection
In order to connect our wires to the Pi CAP, we made use of 3.2mm ring crimp terminals, and screwed these to the Pi CAP terminal pads using 12mm M3 countersunk machine screws and M3 lock nuts. The wires were crimped to the crimp terminals using a crimping tool.
Because we needed to be able to transport each of our tables separately, the wires for one of the tables were not connected directly to the Pi CAP, but were instead screwed into the female side of half of a 12 terminal plug in connector which was then screwed to the underside of the table.
The male side of the plug in connector was wired to the Pi CAP.
When setting up the tables, therefore, it is simply a matter of pushing the male side of the terminal connector into the female side.
The final stage of the project was to provide a monitor. For this, we decided we wanted something fairly light and compact, and we were lucky enough to have a small 11 inch HDMI monitor available. In order to attach the monitor to one of the game tables we used a piece of A4 sized perspex which we drilled out with a matrix of holes for the monitor and holes to attach to the table itself. The picture below shows the monitor mounted on the table.