The Musical Table is a toy table that allows kids to play musical phrases by moving toys around the surface.Each of seven switches can play different musical phrases in four bases, making 27 different musical phrases in total.Some of the phrases are musically related and some of them are not. This toy table can help kids to develop musicality by playing phrases in logical order. The table also allows you to play two phrases at the same time. Depending on which phrases are played together, the sounds can be melodic or chaotic.

Step 1: Product Details

Supplies

- Aluminum foil tape

- Solid hookup wire

- Ribbon wire

- 2 Arduinos

-12 10 K resistors

- 2 speakers

- 4 sheets of foam board (20 “x 30”)

- 7 toy robots (or any other your favorite toy figure)

- 28-ohms speakers

- screws/ nuts (to secure the table on a stand. But optional.)

Tools

- Wire stripper

- Utility knife

- Soldering iron/solder

- Solderless breadboard

- Ruler

Step 2: Wiring the Table

Make four sets of three 1k pull down resistors that connects Arduino pins (pin 2 – pin 13) to ground. Use different colors of wires for each set to distinguish the groups easily.

Base1connection:Connects to digital pin 13, 12, and 11 to a breadboard. Add another wire next to pin 13 on the breadboard, and connect it to the power.
Add pull down resistor (a resistor that connects to ground) between each pin and ground.
Base2 connection: Leave some space on the board and connect digital pin 10, 9, and 8 to the circuit board and power in the same way as step 1 and step 2.
Base3 connection: Take the second Arduino board and connect digital pin 7, 6, and 5 to the same breadboard.
Add pull down resistor betweenpins (digital pin 7, 6, and 5) and ground.
Add another wire next to pin 7 that connects to power.
Base 4 connection: Leave some space below base 3 connection on the board and connect digital pin 4, 3, and 2 to the circuit board and power in the same way as step 4, 5 and 6, except this time the power is connected to a wire next to pin 4.

Step 3: Creating a Melody (Arduino)

An Arduino board makes only one tone at a time (I’m sure there’s away you can get around that, leave a comment if you know how). To have more than one notes played simultaneously, I am using two Arduino boards.
Making a melody entails three variables: pitch, duration, and number of notes. The code is based on Arduino/Tutorial/Melody created by Tom Igoe. You can find the code here. A melody is called when if statement condition is met. The if statement searches for the combinations of three digital pins.

In pseudo code

If (Pin 13 == HIGH && PIN 12==LOW && Pin 11== HIGH) {playtone 3; }

In order to make 14 arrays of notes and durations, I created a class of combinations of notes and duration arrays.

Step 4: Making a Soft Swtich With Conductive Tape(one Half of the Swtich)

Make seven different combinations of switches that play a musical phrase when connected to a base. Each switch has four bars made of conductive tape. The first bar connects to the power and the rest connect to three pins on a base.

1. Cut seven 1 3/4” x3” trapezoids from foam board.

2. Cut seven1 1/2” x 1 3/4 squares from foam board.

3. Make combinations.

With 3 pins, you can create 8 different combinations of switches through differing shapes of conductive tape. On/Off indicates when pins are connected to power.

Combination1-On, Off, Off (Power, Pin 13, Pin12, Pin11)

Combination2-On, On, Off

Combination3-On, Off, On

Combination4-On, On, On

Combination5-Off, Off, On

Combination6-Off, On, Off

Combination7-Off, On, On

Combination8 –Off, Off, Off (this means nothing is connected to power. We will skip this one)

4. Here’s an illustration of theswitches and the base pattern. You can use this as a template and cut conductive tape in this shape.

5. Leave 1/4” on each side and attach conductive tape shape on one of the foam squares.

6. After the conductive shape is attached, glue the square switch to a foam trapezoid.

7. Apply hot glue a toy on a trapezoid.

Step 5: Make Trapeziod Insert

Cut out four 1 3/4” x3” trapezoids from the table top panel.
Cut out about 1/16" more space around the trapezoid.

Step 6: Making the Table Top/completing the Switch

parts:

4 bases, we need 4 pieces of 4” x 5 1/2” base panel

4 pieces of 3 “ x 3 3/4” (outside) and 1 1/4” x 1 3/4” (inside) window panel,

4 pieces of 3” x”6 base support.

table top panel (20" x 30")

Combination patterns made from a conductive tape

Here’s an illustrator file of template. (Illustrator file)

Place a window panel on a base panel and trace the outline of the inner window. (picture)
Leave 1/4” on each side, and divide the space into 4 sections and draw lines.
Draw a horizontal line 1/2” from the top.
Draw 4 holes on along the line.
Separate a four-strand ribbon wire at one end, and run one lead through each hole.
Glue the window panel on the base panel.
Tape each stripped lead to the base panel with a strip of conductive tape, following the template.
Solder the opposite side of the wire leads with a header pin.

Step 7: Mounting Speakers on the Sides.

Measure the diameter of the inner circle on the back of the speaker.
Trace the inner circle on both side panels. You can use a circle drawing tool, or find the same size circular shape object and trace the contour.
Cut both circles out.

Insert the speakers into the holes and fasten the speaker with a screw and put a nut on the back to keep it secured.

Step 8: Putting the Table Together

Assemble the table with table top, bottom, and two side panels.

1. Attach a base panel under a trapezoid shape hole on the bottom of the table withhot glue.

2. Cut6” high foam and glue it under the center of a base. This is used as a weight support for the base panel when a user places a toy switch in the base and presses on it.

3. Glue the two side panels on the top panel.

1.Glue the bottom panel. To keep the panels close together, put heavy objects.

2.Put the table on a stand. You can also use a stool as a stand if you don’t’ know how to make one.

Step 9: Connecting the Circuit.

Place the circuit inside the table, and wire the cables from each bases.

Connect the header pins on a ribbon wire of a base and connect to the base 1 circuit, which connects to pin 13, 12, and 11.
Connect the next base to the base2 circuit (pin 10, 9, and 8)
Connect the positive side of the speaker to Arduino on digital pin 7 on thefirst Arduino board and the ground side to ground on the breadboard.
Connect the next base to the circuit, which is wired to the other Arduino board (pin 7, 6, and 5).
Connect the last base to the base 4 circuit. (pin4, 3, and 2)
Connect the positive side of the speaker to the second Arduino on digital pin 8, and the other side to ground on the breadboard.

7. The musical table is completed. Powers one of the Arduinos with an AC adapter, and place a toy on a base to hear an Arduino music.