Dot² - an Interactive Coffee Table

During my internship, I built an interactive Table on which you can run animations, some awesome LED Effects and yeah, Play old school games !!

I got inspiration to create this coffee table from crt4041's Music Visualiser Table

The table is controlled via a Bluetooth app developed using MIT App Inventor.

Let's Start building...!!

Step 1: What All Is Required ?

Hardware Stuff

• Wooden Ply-Board (0.5" thick)
  • 4x - 8" by 28"
  • 1x - 28" by 28"
• Foam-Board (around 10-11 sq. ft.)
• Acrylic - Milky White - 28" by 28" 3mm
• 4x Aluminium L-strip 29" Long
• Self Tapping Screws (M4 will work)
• Nails
• Side Beading for tables

• Solder

Electronic Stuff

• Pixel LEDs ( or WS2811 Pixel Module) - 196 Bulbs.
• Arduino Mega 2560
• Bluetooth Module - HC-05/06
• 330 ohm Resistor
• 1x Zero PCB
• Male Headers
• Connecting Wire 5V 20A
• Switching Power Supply

Tools Used

• Circular Saw
• Jig-Saw
• Drilling Machine with 12mm Drill Bit
• Screw-Driver
• Hot Glue Gun
• Soldering Iron
• Dremel Rotary Tool (for finishing of grid)
• Disc Sander
• Precision Knife
• Fevi-Bond (or SuperGlue)
• Hammer

Step 2: Preparing Base for LEDs

Now Pick-up a 28" by 28" Ply-Board and make a uniform grid with each cell side measuring 2 inches.

Mark centre of each cell and START DRILLING...

GO! GO! GO!

Step 3: End the Drilling Madness...

After drilling all the way to 196 holes, now it's time to fix LEDs.

NOTE: Fix LEDs in the manner shown in above pictures else play around with software and code.

Now, Hot Glue LEDs onto Base Board.

Step 4: Software... Let's Make It Alive

There are two different softwares available to use it with

1. GLEDIATOR by SolderLabs.de

2. Custom Code with bluetooth added to hardware so that you can run 8-bit games on the table.

Step 5: Making Circuit for Pairing It With Mobile for Playing Games

To play games I designed a circuit involving Bluetooth module and Arduino Mega. This uses the app on phone to connect with table and use your mobile as controller for the table.

I've used PIN 6 as SIGNAL PIN to LED Strip. You can change as per your convenience but be sure you change that in Arduino code too !!

Then this setup was fixed on underside of table and electronics part is done.

Step 6: Coding Arduino

Use following attached files to download code for Arduino Mega 2560.

Note : Code will not work on Arduino Uno/Nano/Pro Mini/Micro as they all have 32B Flash but the required is more then 32 KB.

LED-TABLE.zip is code involving Games and some animations for table control using mobile over bluetooth

GLEDIATOR+Arduino_Code.zip is for using table always being connected to a PC running GLEDIATOR Software

NOTE: If you want to use GLEDIATOR Software there is no boundation to use Arduino Mega 2560.

UPDATE : I have included libraries in below zip file names Libraries.zip

Step 7: Time for a Test-Run

Test Run with couple of different Patterns using GLEDIATOR SOFTWARE and Arduino Code provided by GLEDIATOR.

Step 8: App for Controlling the Table

You can Download app from Google Play. In case, you want to alter the app you can always do that at MIT APP Inventor by importing the below attached .aia file.

Connect to your table and start playing...!!

Step 9: Cutting the GRID

I used 4mm White Foam Board for making the grid.

I marked 2 in. by 28 in. rectangles and using a table saw, I made 26 of them (13 for horizontal layout and 13 for vertical layout). Then using a jig-saw I made 4 mm wide equally spaced indents so that foam-board strips could be interlocked with each other forming a grid.

Step 10: Preparing the Outer Shell to Encase the Table Inside It

using 4x 8" by 28" 8mm Wood planks I prepared the boundary with support leaving 3" from the top inside the box to support the board mounted with LEDs. as shown in pictures and nailed them all together after applying sufficient amount of wood glue so they could bound more strongly.

Then slowly lowered down the grid inside the Box lit up to see everything still worked fine. Then to see if diffusion was good I placed Milky White Acrylic Sheet on top and everything worked as planned :D

For temporarily fixing the acrylic on top of table I used Aluminium L-Brackets to hold the Acrylic sheet in place

Step 11: Giving Table Final Look and a Base to Stand On.

A big thanks to Canvas of Dreams for helping me do this awesome wood work for the table. Do check out his channel guys !!

Side Beading for tables were sliced half and pasted and nailed onto the table's outer shell as shown in pictures. Then after they were dried 4 base legs were nailed to the table's base and a coat of PU Stain was applied to give it a final finish.

After everything was done a thin 2mm glass was laid on top of acrylic to prevent it from scratches and Coffee stains.

Step 12: Taa Daa It's Ready !!