Published April 27, 2017 © CC BY-NC

Wavepad

Gesture Controlled Raspberry Pi Music Player

IntermediateFull instructions provided12 hours3,745

Things used in this project

Hardware components

Raspberry Pi 3 Model B

Speaker

Ultrasonic Sensor

Photodiode

IR LED

Resistor 1k ohm

Resistor 10k ohm

Resistor 100 ohm

Single Turn Potentiometer- 10k ohms

PCB

LED Blue

IC LM324SN

Jumper wires (generic)

Hand tools and fabrication machines

Soldering iron (generic)

Story

Wavepad is a gesture controlled music player. It is built using Raspberry pi microcontroller. With Wavepad you can increase and decrease the volume of the song, play next song, play previous song, pause and resume song. To recognise the gestures we are using 2 types of sensors. First one is Ultrasonic sensor which is used to control the volume and Other is IR proximity sensor x 2 which are used to change ,pause and resume songs.

Step 1: Building Circuit

In our circuit there are three main parts.

1. IR Proximity sensor

2. Ultrasonic Sensor

3. LED's

We will go to each parts step by step.

Step 2: Build IR Proximity Sensor

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A proximity sensor is a sensor able to detect the presence of nearby objects without any physical contact. We are using 2 proximity sensors in our project it will be used to play next or previous and pause the song.

To build the circuit follow the above circuit diagram.

Explanation of Diagram

We are using pair of Photodiode and IR LED's. Photodiode is connected to 10K Resistor while IR LED connected to 100 Ohm Resistor. S1 & S2 outputs are connected to LM324SN Operational Amplifier which amplifies the voltage according the Potentiometer connected. The output of the LM324SN is 5V. But we need 3.3.V to Raspberry Pi therefore we are using Voltage Divider Circuit.

Connect Output O1 & O2 to GPIO 27 & 17 Pins respectively.

Step 3: Connecting Ultrasonic Sensor

1 / 3

We connect Ultrasonic Sensor as follows

VCC -----> 5V

GND -----> GND

TRIGGER----> GPIO 04

ECHO -----> Voltage Divider Circuit------>GPIO 22

Echo gives output 5V but Raspberry pi needs 3.3V therefore we are using Voltage Divider Circuit to make voltage equivalent to 3.3V.

Step 4: Connecting LED's

1 / 4

LED's are used to Indicate the volume level. We are using 10 LED's but you can use as many as you want. Each LED's Cathod is connected to common ground and Anode connected to 1K Resistor , then connected to GPIO Pins from Raspberry Pi.

Connect LED's To Following GPIO Pins:

LED1 --> GPIO 14

LED2 --> GPIO 15

LED3 --> GPIO 18

LED4 -- > GPIO 23

LED5 --> GPIO 24

LED6 --> GPIO 25

LED7 --> GPIO 8

LED8 --> GPIO7

LED9 --> GPIO 12

LED10 --> GPIO16

Step 5: Coding

Steps to run the program:

1. Download the wavepad.py file and put it in /home/pi directory of raspberry pi.

2. Put songs in /home/pi/Music directory

3. Now we need our python script to execute at startup. To do this follow these steps:

a. Type sudo nano .bashrc

b. Add this line without quotes "sudo python wavepad.py &"

c. Go to Application Menu -> Preferences -> Raspberry pi configuration -> Then click on To CLI Radio button.

d. Restart your pi

Step 6: Finishing Up.

1 / 4

Now it's time to put our circuit in case. I didn't have 3D printer that's why i handmade this simple box using cardboard. And just stick printed paper on it.

Schematics

File missing, please reupload.

Code

wavepad.py

#!/user/bin/python

import os
import glob
import subprocess
import RPi.GPIO as GPIO
import time
from time import sleep

TRIGGER = 4
ECHO = 22
LED1 = 14
LED2 = 15
LED3 = 18
LED4 = 23
LED5 = 24
LED6 = 25
LED7 = 8
LED8 = 7
LED9 = 12
LED10 = 16
LEFT_SENSOR=27
RIGHT_SENSOR=17

GPIO.setmode(GPIO.BCM)
GPIO.setup(LEFT_SENSOR,GPIO.IN)
GPIO.setup(RIGHT_SENSOR,GPIO.IN)

GPIO.setup(TRIGGER,GPIO.OUT)
GPIO.setup(ECHO,GPIO.IN)

GPIO.setup(LED1,GPIO.OUT)
GPIO.setup(LED2,GPIO.OUT)
GPIO.setup(LED3,GPIO.OUT)
GPIO.setup(LED4,GPIO.OUT)
GPIO.setup(LED5,GPIO.OUT)
GPIO.setup(LED6,GPIO.OUT)
GPIO.setup(LED7,GPIO.OUT)
GPIO.setup(LED8,GPIO.OUT)
GPIO.setup(LED9,GPIO.OUT)
GPIO.setup(LED10,GPIO.OUT)

os.chdir('/home/pi/Music')
f = glob.glob('*mp3')
h = len(f)
status = 1
pointer = 0
start = 0
volume = 8
def led():
    if volume==1:
        GPIO.output(LED1,True)
        GPIO.output(LED2,False)
        GPIO.output(LED3,False)
        GPIO.output(LED4,False)
        GPIO.output(LED5,False)
        GPIO.output(LED6,False)
        GPIO.output(LED7,False)
        GPIO.output(LED8,False)
        GPIO.output(LED9,False)
        GPIO.output(LED10,False)
    elif volume==2:
        GPIO.output(LED1,True)
        GPIO.output(LED2,True)
        GPIO.output(LED3,False)
        GPIO.output(LED4,False)
        GPIO.output(LED5,False)
        GPIO.output(LED6,False)
        GPIO.output(LED7,False)
        GPIO.output(LED8,False)
        GPIO.output(LED9,False)
        GPIO.output(LED10,False)
    elif volume==3:
        GPIO.output(LED1,True)
        GPIO.output(LED2,True)
        GPIO.output(LED3,True)
        GPIO.output(LED4,False)
        GPIO.output(LED5,False)
        GPIO.output(LED6,False)
        GPIO.output(LED7,False)
        GPIO.output(LED8,False)
        GPIO.output(LED9,False)
        GPIO.output(LED10,False)
    elif volume==4:
        GPIO.output(LED1,True)
        GPIO.output(LED2,True)
        GPIO.output(LED3,True)
        GPIO.output(LED4,True)
        GPIO.output(LED5,False)
        GPIO.output(LED6,False)
        GPIO.output(LED7,False)
        GPIO.output(LED8,False)
        GPIO.output(LED9,False)
        GPIO.output(LED10,False)
    elif volume==5:
        GPIO.output(LED1,True)
        GPIO.output(LED2,True)
        GPIO.output(LED3,True)
        GPIO.output(LED4,True)
        GPIO.output(LED5,True)
        GPIO.output(LED6,False)
        GPIO.output(LED7,False)
        GPIO.output(LED8,False)
        GPIO.output(LED9,False)
        GPIO.output(LED10,False)
    elif volume==6:
        GPIO.output(LED1,True)
        GPIO.output(LED2,True)
        GPIO.output(LED3,True)
        GPIO.output(LED4,True)
        GPIO.output(LED5,True)
        GPIO.output(LED6,True)
        GPIO.output(LED7,False)
        GPIO.output(LED8,False)
        GPIO.output(LED9,False)
        GPIO.output(LED10,False)
    elif volume==7:
        GPIO.output(LED1,True)
        GPIO.output(LED2,True)
        GPIO.output(LED3,True)
        GPIO.output(LED4,True)
        GPIO.output(LED5,True)
        GPIO.output(LED6,True)
        GPIO.output(LED7,True)
        GPIO.output(LED8,False)
        GPIO.output(LED9,False)
        GPIO.output(LED10,False)
    elif volume==8:
        GPIO.output(LED1,True)
        GPIO.output(LED2,True)
        GPIO.output(LED3,True)
        GPIO.output(LED4,True)
        GPIO.output(LED5,True)
        GPIO.output(LED6,True)
        GPIO.output(LED7,True)
        GPIO.output(LED8,True)
        GPIO.output(LED9,False)
        GPIO.output(LED10,False)
    elif volume==9:
        GPIO.output(LED1,True)
        GPIO.output(LED2,True)
        GPIO.output(LED3,True)
        GPIO.output(LED4,True)
        GPIO.output(LED5,True)
        GPIO.output(LED6,True)
        GPIO.output(LED7,True)
        GPIO.output(LED8,True)
        GPIO.output(LED9,True)
        GPIO.output(LED10,False)
    elif volume==10:
        GPIO.output(LED1,True)
        GPIO.output(LED2,True)
        GPIO.output(LED3,True)
        GPIO.output(LED4,True)
        GPIO.output(LED5,True)
        GPIO.output(LED6,True)
        GPIO.output(LED7,True)
        GPIO.output(LED8,True)
        GPIO.output(LED9,True)
        GPIO.output(LED10,True)

def distance():
    GPIO.output(TRIGGER,True)
    time.sleep(0.00001)
    GPIO.output(TRIGGER,False)
    StartTime = time.time()
    StopTime = time.time()
    while GPIO.input(ECHO) == 0:
        StartTime = time.time()
    while GPIO.input(ECHO) == 1:
        StopTime = time.time()
    TimeElapsed = StopTime-StartTime
    distance=(TimeElapsed*34300)/2
    return distance



if __name__=='__main__':
    try:
        for counter in range(1,10):
            volume = counter
            led()
            sleep(0.1)
        for counter in range(1,9):
            volume = 10-counter
            led()
            sleep(0.1)
        for counter in range(1,8):
            volume = counter
            led()
            sleep(0.1)
        while True:
            
            led()
            dist = int(distance())
            if(status==1):
                player = subprocess.Popen(["omxplayer",f[pointer]],stdin=subprocess.PIPE)
                fi = player.poll()
                status = 0
                start = 0
                volume = 8
            if(dist>=0 and dist<=35):
                vol = dist/3
                if(vol>volume):
                    for counter in range(1,vol-volume):
                        player.stdin.write("+")
                        volume = volume + 1
                        led()
                        sleep(0.1)
                elif(vol<volume):
                    for counter in range(1,volume-vol):
                        player.stdin.write("-")
                        volume = volume - 1
                        led()
                        sleep(0.1)
            if(GPIO.input(LEFT_SENSOR)==True and GPIO.input(RIGHT_SENSOR)==True):
                sleep(0.5)
                fi = player.poll()
                if fi!=0:
                    player.stdin.write("p")
            elif(GPIO.input(LEFT_SENSOR)==True):
                for counter in range(0,10000):
                    if(GPIO.input(RIGHT_SENSOR)==True):
                        if start==0:
                            player.stdin.write("q")
                            status = 1
                            pointer = pointer +1
                            if(pointer>h-1):
                                pointer = 0
                            break
                    sleep(0.0001)
            elif(GPIO.input(RIGHT_SENSOR)==True):
                for counter in range(0,10000):
                    if(GPIO.input(LEFT_SENSOR)==True):
                        if(start==0):
                            player.stdin.write("q")
                        status = 1
                        pointer = pointer - 1
                        if(pointer<0):
                            pointer = h-1
                        break
                    sleep(0.0001)
            else:
                fi = player.poll()
                if(fi==0 and start==0):
                    status = 1
                    pointer = pointer +1
                    if(pointer>h-1):
                        pointer = 0
                sleep(0.1)
    except KeyboardInterrupt:
            print("Stopped by user")
            GPIO.cleanup()

Credits

Tejas Ozarkar

2 projects • 6 followers

I'm android developer and robotics enthusiast.

Wavepad

Things used in this project

Hardware components

Hand tools and fabrication machines

Story

Step 1: Building Circuit

Step 2: Build IR Proximity Sensor

Step 3: Connecting Ultrasonic Sensor

Step 4: Connecting LED's

Step 5: Coding

Step 6: Finishing Up.

Schematics

IR sensor pair

Ultrasonic sensor connection

Code

wavepad.py

Credits

Tejas Ozarkar

Comments

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Wavepad

Wavepad

Things used in this project

Hardware components

Hand tools and fabrication machines

Story

Step 1: Building Circuit

Step 2: Build IR Proximity Sensor

Step 3: Connecting Ultrasonic Sensor

Step 4: Connecting LED's

Step 5: Coding

Step 6: Finishing Up.

Schematics

IR sensor pair

Ultrasonic sensor connection

Code

wavepad.py

Credits

Tejas Ozarkar

Comments

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