Octo-hugs: a *Huggable* Octopus Plush Toy

Hello! Today I'll be showing you how to recreate my huggable octopus plush toy.

This octopus uses a pressure sensor to play sounds either louder or softer and show lights as either brighter or lower depending on how hard the child squeezes it. I used calming water and bubble sounds to play when you squeeze the toy, but you can use water music/calming sounds that you wish. I made this toy with my size dimensions in mind and I am 5ft 4in, 167cm. If you make this toy for a child in your life, tweet at me (@bexthehexx) and let me know! You can also make this octopus for yourself! Everyone needs a hug sometimes. :)

For your supplies, you'll need:

- Base Fabric for legs (about 1 yard, depending on the height of the child)

- Stuffing - I use polyester fill

- Needle and Thread or Sewing Machine

- Conductive Fabric

- Velostat

- Arduino

- Alligator Clips

- Wires

- 2 1K Resistors

- LEDs (color of your choice)

- DF Player Mini

- Micro SD Card

- Speakers

- Soft Fabric for outside plush (about 2 yards, depending on the height of the child)

Your octopus will need base legs, this way you can test out what size works for you or your child. The legs can be made of any material, I used an old bedsheet. Please make sure your child is not allergic to this material because it will be used for your final octopus. Let's make some leggies!

First off, you need to prepare our legs. Once you have your base material for the legs (about > 1 yard, depending on the size of the toy), you will need to create 8 legs for your octopus. Feel free and experiment with the size of the legs (length and width) to make sure it is comfortable and huggable.

You will cut your octopus legs to size, you will find a (not to scale) pattern above. Measure 8 rectangles to be 18in by 3in and cut them out - no need to cut out the head yet.

After cutting out the material, start with one leg. Fold the leg in half with wrong sides together to get a long flat rectangle. Sew the two long edges together to create a long tube. Turn the tube right side out and stuff your lovely octopus leggie with stuffing. Sew up the remaining top and bottom sides of the leg. Now you have 1 octopus leg. Great! Repeat this process 7 more times until you have sewed and stuffed all 8 of your octopus legs.

After you get your 8 legs, or you could even start testing at 3 or 4 legs, you can get a feel for how this toy will fit on you and/or your child. Looking back on my project, I definitely made my legs too big for me - remember, you will end up having 8 lovely legs. Though, through testing your legs you can decide whether they are too big or too small! This toy should be as plushy, yet comfortable, as possible.

Once you have completed testing and creating your base legs, congratulations! You have created 8 weird squishy tubes that will become your octopus toy. Finish up any testing with yourself or child and once you have 8 legs you are happy with, then connect them. You can try connecting the legs with safety pins, hair ties, scrap pieces of fabric, etc... the best way for me to connect my legs was to sew them together, but choose whatever way you feel most comfortable. To sew your legs together use some thread that is sturdy and not too thin, and loop them together however you wish.

Now that the base leggies are created, it is a good time to figure out your electronics. If you feel you need to, create a practice fabric pressure sensor with some normal fabric, velostat, and copper tape or conductive fabric. As you can see from the first video above, when you squeeze the sensor the LED gets brighter. This it the instructable I (loosely) followed to make my practice sensor: https://www.instructables.com/id/Flexible-Fabric-Pressure-Sensor/. The diagram hookup above shows how you can quickly test out your pressure sensor. The grey box represents the sensor, which should be connected to the two different layers of conductive fabric. Once you know how to get it working on a small scale, then it is time to create the first pressure sensor for the octopus legs.

The following measurements were for my octopus leg size, but go ahead and modify them for your project. For the long pressure sensor, get a 12in by 2in piece of velostat and cut out two pieces of conductive fabric to be about 8in by 1.5in. The important thing here is that your conductive fabric is smaller than your velostat. Sew your conductive fabric to two pieces of felt of the same size, 12in by 2in. Now sandwich the pieces together, with the conductive fabric pieces facing each other through the velostat. I wired up the sensor, one piece of conductive fabric to the LED's positive and the other piece of conductive fabric to the resistor which then goes to the LED's negative (see the second video and diagram hookup above for a visual). Now you can get your hands on some electronics.

Hookup your DF Player Mini using the arduino diagram above. The code below is for both the DFPlayer Mini and LED, so feel free to modify and use for your project! The code utilizes the DFPlayerMini_Fast arduino library to play and pause the sounds. Make sure that you have a Micro SD inserted into the module to test! Label your sounds as '001', '002, '003, etc. All you really need is one sound on the card to test. In the code below, the analog input from the pressure sensor affect both the LED's brightness and DF Player Mini's volume. The library comes with a function to change the volume (values 0 to 30) and functions to play, pause, and loop sounds. You can learn more about the library here: https://github.com/PowerBroker2/DFPlayerMini_Fast.

After fixing up the code and getting all your wires together, make sure to test the output to make sure you are achieving the desired interaction. Modify the code snippet below for your octopus' needs - especially the values in the map() function calls since your input from the pressure sensor will be different.

/////////////////////////
//
// Octo-hugs code
// by Bex
//
/////////////////////////

int analogPin = A0; // pressure sensor pin
int ledPin = 9; // led pin
int val = 0; // variable to store the analog value read
int mappedVal = 0; //variable to be mapped to hug tightness
boolean hug = false; // is octopus being hugged ?
int hugVolume = 0;


#include <SoftwareSerial.h>
#include <DFPlayerMini_Fast.h>
SoftwareSerial mySerial(10, 11); // RX pin, TX pin
DFPlayerMini_Fast myMP3;
int playCount = 0;
int pauseCount = 0;

void setup() {
  Serial.begin(9600);
  mySerial.begin(9600);
  myMP3.begin(mySerial);
  myMP3.volume(10);
  
  pinMode(ledPin, OUTPUT);
  delay(1000);
}

void loop() {
  val = analogRead(analogPin); // read the input pin
  mappedVal = map(val, 0, 25, 0, 255);
  if(mappedVal > 255) {
    mappedVal = 255;
  }
  analogWrite(ledPin, mappedVal);

  if(val > 10) {
    hug = true;
  } else {
    hug = false;
  }

  if(hug) {
    if(playCount < 1) {
      pauseCount = 0;   
      myMP3.volume(20);
      myMP3.play(1);
      Serial.println("playyy!");
      playCount++;
      delay(1000);
    }
    hugVolume = map(val, 10, 25, 10, 25);
    myMP3.volume(hugVolume);
  } else {
    if(pauseCount < 1) {
      playCount = 0;
      myMP3.pause();
      Serial.println("pause!");
      pauseCount++;
      delay(1000);
    }
  }
}

It is time to get your hands on your nice plush fabric! Bringing back the (not to scale) fabric pattern from earlier, cut the 8 rectangles and circle out from your nice fabric for the octopus leggies and head. Sew the nice fabric onto your 8 legs, or glue if you prefer. Sew your pressure sensor(s) onto your leg(s) and make sure to cut the two pressure sensor wires long so you can connect it to the rest of your electrical components.

Then, you are going to get some polyester fill for the head, and attach your arduino, speaker, and DF Player Mini into your octopus head. As a prototype it is totally okay to tape them in, but for a long term solution it might be best to sew a compartment for all the components at the base of the head. While testing, keep your battery outside your octopus so you can easily turn it on and off. Before you close up your octopus head - which you can sew, add buttons, tape, or tie - connect all the components and double check it all works as intended. Make sure to not sew the head shut completely, it is best to have an easily accessible way for you to open up - but not for little hands to get into!

Congratulations! Hug your octopus to make sure octo-hugs works! If you have any questions at all feel free to reach out to me, @bexthehexx on twitter. Now it's time to give your octopus a hug and relax in the sounds of your toy!