Nabil Ghaly
Created December 12, 2019 © GPL3+

Gorilla Drumbot

Using Alexa and EV3 Lego Gorilla to play drum on the beat

IntermediateFull instructions provided10 hours45

Things used in this project

Hardware components

EV3 Programming Brick / Kit
LEGO MindStorms EV3 Programming Brick / Kit
×1
8 inch Drum
×1

Software apps and online services

Microsoft Visual Studio Code

Story

Read more

Schematics

Gorilla motor wiring

Gorilla motor wiring

Lego Gorilla Build Instruction

Lego Gorilla Build Instruction

Code

drumbot.py

Python
python coded needed to run the drumbot
#!/usr/bin/env python3
# Copyright 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
# 
# You may not use this file except in compliance with the terms and conditions 
# set forth in the accompanying LICENSE.TXT file.
#
# THESE MATERIALS ARE PROVIDED ON AN "AS IS" BASIS. AMAZON SPECIFICALLY DISCLAIMS, WITH 
# RESPECT TO THESE MATERIALS, ALL WARRANTIES, EXPRESS, IMPLIED, OR STATUTORY, INCLUDING 
# THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT.

import os
import sys
import time
import logging
import threading
import random

from agt import AlexaGadget

from ev3dev2.led import Leds
from ev3dev2.sound import Sound
from ev3dev2.motor import OUTPUT_A, OUTPUT_D, LargeMotor

# Set the logging level to INFO to see messages from AlexaGadget
logging.basicConfig(level=logging.INFO, stream=sys.stdout, format='%(message)s')
logging.getLogger().addHandler(logging.StreamHandler(sys.stderr))
logger = logging.getLogger(__name__)


class MindstormsGadget(AlexaGadget):
    """
    A Mindstorms gadget that performs movement in sync with music tempo.
    """

    def __init__(self):
        """
        Performs Alexa Gadget initialization routines and ev3dev resource allocation.
        """
        super().__init__()

        # Ev3dev initialization
        self.leds = Leds()
        self.sound = Sound()
        self.left_motor = LargeMotor(OUTPUT_A)
        self.right_motor = LargeMotor(OUTPUT_D)

        # Gadget states
        self.bpm = 0
        self.trigger_bpm = "off"

    def on_connected(self, device_addr):
        """
        Gadget connected to the paired Echo device.
        :param friendly_name: the friendly name of the gadget that has connected to the echo device
        """
        self.leds.set_color("LEFT", "GREEN")
        self.leds.set_color("RIGHT", "GREEN")
        logger.info("{} connected to Echo device".format(self.friendly_name))

    def on_disconnected(self, device_addr):
        """
        Gadget disconnected from the paired Echo device.
        :param friendly_name: the friendly name of the gadget that has disconnected from the echo device
        """
        self.leds.set_color("LEFT", "BLACK")
        self.leds.set_color("RIGHT", "BLACK")
        logger.info("{} disconnected from Echo device".format(self.friendly_name))

    def on_alexa_gadget_musicdata_tempo(self, directive):
        """
        Provides the music tempo of the song currently playing on the Echo device.
        :param directive: the music data directive containing the beat per minute value
        """
        tempo_data = directive.payload.tempoData
        for tempo in tempo_data:

            print("tempo value: {}".format(tempo.value), file=sys.stderr)
            if tempo.value > 0:
                self.leds.set_color("LEFT", "GREEN")
                self.leds.set_color("RIGHT", "GREEN")
                time.sleep(3)
                # starts the drum loop
                self.trigger_bpm = "on"
                threading.Thread(target=self._drum_loop, args=(tempo.value,)).start()

            elif tempo.value == 0:
                # stops the drum loop
                self.trigger_bpm = "off"
                self.leds.set_color("LEFT", "BLACK")
                self.leds.set_color("RIGHT", "BLACK")

    def _drum_loop(self, bpm):
        """
        Perform motor movement in sync with the beat per minute value from tempo data.
        :param bpm: beat per minute from AGT
        """
        color_list = ["GREEN", "RED", "AMBER", "YELLOW"]
        led_color = random.choice(color_list)
        motor_speed = 400
        milli_per_beat = min(1000, (round(60000 / bpm)) * 0.65)
        print("Adjusted milli_per_beat: {}".format(milli_per_beat), file=sys.stderr)
        while self.trigger_bpm == "on":

            # Alternate led color and motor direction
            led_color = "BLACK" if led_color != "BLACK" else random.choice(color_list)
            motor_speed = -motor_speed

            self.leds.set_color("LEFT", led_color)
            self.leds.set_color("RIGHT", led_color)
            self.right_motor.run_timed(speed_sp=motor_speed, time_sp=150)
            self.left_motor.run_timed(speed_sp=-motor_speed, time_sp=150)
            time.sleep(milli_per_beat / 1000)

        print("Exiting BPM process.", file=sys.stderr)


if __name__ == '__main__':

    gadget = MindstormsGadget()

    # Set LCD font and turn off blinking green LEDs
    os.system('setfont Lat7-Terminus12x6')
    gadget.leds.set_color("LEFT", "BLACK")
    gadget.leds.set_color("RIGHT", "BLACK")

    # Startup sequence 
    gadget.sound.play_song((('C4', 'e'), ('D4', 'e'), ('E5', 'q')))
    gadget.leds.set_color("LEFT", "GREEN")
    gadget.leds.set_color("RIGHT", "GREEN")

    # Gadget main entry point
    gadget.main()

    # Shutdown sequence
    gadget.sound.play_song((('E5', 'e'), ('C4', 'e')))
    gadget.leds.set_color("LEFT", "BLACK")
    gadget.leds.set_color("RIGHT", "BLACK")

drumbot.ini

INI
drumbot.ini
# Copyright 2019 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
# 
# You may not use this file except in compliance with the terms and conditions 
# set forth in the accompanying LICENSE.TXT file.
#
# THESE MATERIALS ARE PROVIDED ON AN "AS IS" BASIS. AMAZON SPECIFICALLY DISCLAIMS, WITH 
# RESPECT TO THESE MATERIALS, ALL WARRANTIES, EXPRESS, IMPLIED, OR STATUTORY, INCLUDING 
# THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT.

[GadgetSettings]
amazonId = [amazonId]
alexaGadgetSecret = [amazonGadgetSecret]

[GadgetCapabilities]
Alexa.Gadget.MusicData = 1.0 - tempo
Alexa.Gadget.StateListener = 1.0 - wakeword

Credits

Nabil Ghaly

Nabil Ghaly

1 project • 0 followers
Maker, sewer, clothing and fashion expert

Comments