Hamza Chaudhary
Published © GPL3+

AlexBot

This robot can be controlled by Amazon Alexa and can do things like move in all directions and dance to music. It is an easy build as well

BeginnerShowcase (no instructions)3 hours481
AlexBot

Things used in this project

Hardware components

Mindstorms EV3 Programming Brick / Kit
LEGO Mindstorms EV3 Programming Brick / Kit
×1
Echo Dot
Amazon Alexa Echo Dot
×1
Flash Memory Card, SD Card
Flash Memory Card, SD Card
×1

Software apps and online services

VS Code
Microsoft VS Code

Story

Read more

Custom parts and enclosures

Building pics

Video demo of robot

Building pic 1

Schematics

Wiring

Code

Mission 1 code

Python
This code was created by amazon and not me
#!/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

from ev3dev2.sound import Sound
from ev3dev2.led import Leds

from agt import AlexaGadget

# set logger to display on both EV3 Brick and console
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):
    """
    An Mindstorms gadget that will react to the Alexa wake word.
    """

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

        self.leds = Leds()
        self.sound = Sound()

    def on_connected(self, device_addr):
        """
        Gadget connected to the paired Echo device.
        :param device_addr: the address of the device we connected to
        """
        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 device_addr: the address of the device we disconnected from
        """
        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_statelistener_stateupdate(self, directive):
        """
        Listens for the wakeword state change and react by turning on the LED.
        :param directive: contains a payload with the updated state information from Alexa
        """
        color_list = ['BLACK', 'AMBER', 'YELLOW', 'GREEN']
        for state in directive.payload.states:
            if state.name == 'wakeword':

                if state.value == 'active':
                    print("Wake word active", file=sys.stderr)
                    self.sound.play_song((('A3', 'e'), ('C5', 'e')))
                    for i in range(0, 4, 1):
                        self.leds.set_color("LEFT", color_list[i], (i * 0.25))
                        self.leds.set_color("RIGHT", color_list[i], (i * 0.25))
                        time.sleep(0.25)

                elif state.value == 'cleared':
                    print("Wake word cleared", file=sys.stderr)
                    self.sound.play_song((('C5', 'e'), ('A3', 'e')))
                    for i in range(3, -1, -1):
                        self.leds.set_color("LEFT", color_list[i], (i * 0.25))
                        self.leds.set_color("RIGHT", color_list[i], (i * 0.25))
                        time.sleep(0.25)


if __name__ == '__main__':

    gadget = MindstormsGadget()

    # Set LCD font and turn off blinking 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")

Mission 2

Python
#!/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_B, OUTPUT_C, 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_B)
        self.right_motor = LargeMotor(OUTPUT_C)

        # 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:
                # dance pose
                self.right_motor.run_timed(speed_sp=750, time_sp=2500)
                self.left_motor.run_timed(speed_sp=-750, time_sp=2500)
                self.leds.set_color("LEFT", "GREEN")
                self.leds.set_color("RIGHT", "GREEN")
                time.sleep(3)
                # starts the dance loop
                self.trigger_bpm = "on"
                threading.Thread(target=self._dance_loop, args=(tempo.value,)).start()

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

    def _dance_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")

Extra code in index.js folder

JavaScript
Replace the index.js file code with this code. It has some custom code inside that can help orientate the direction of movement for alexa.
/*
 * 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.
*/

// This sample demonstrates sending directives to an Echo connected gadget from an Alexa skill
// using the Alexa Skills Kit SDK (v2). Please visit https://alexa.design/cookbook for additional
// examples on implementing slots, dialog management, session persistence, api calls, and more.

const Alexa = require('ask-sdk-core');
const Util = require('./util');
const Common = require('./common');

// The namespace of the custom directive to be sent by this skill
const NAMESPACE = 'Custom.Mindstorms.Gadget';

// The name of the custom directive to be sent this skill
const NAME_CONTROL = 'control';

const LaunchRequestHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'LaunchRequest';
    },
    handle: async function(handlerInput) {

        let request = handlerInput.requestEnvelope;
        let { apiEndpoint, apiAccessToken } = request.context.System;
        let apiResponse = await Util.getConnectedEndpoints(apiEndpoint, apiAccessToken);
        if ((apiResponse.endpoints || []).length === 0) {
            return handlerInput.responseBuilder
            .speak(`I couldn't find an EV3 Brick connected to this Echo device. Please check to make sure your EV3 Brick is connected, and try again.`)
            .getResponse();
        }

        // Store the gadget endpointId to be used in this skill session
        let endpointId = apiResponse.endpoints[0].endpointId || [];
        Util.putSessionAttribute(handlerInput, 'endpointId', endpointId);

        return handlerInput.responseBuilder
            .speak("Welcome, you can start issuing move commands")
            .reprompt("Awaiting commands")
            .getResponse();
    }
};

// Add the speed value to the session attribute.
// This allows other intent handler to use the specified speed value
// without asking the user for input.
const SetSpeedIntentHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'IntentRequest'
            && Alexa.getIntentName(handlerInput.requestEnvelope) === 'SetSpeedIntent';
    },
    handle: function (handlerInput) {

        // Bound speed to (1-100)
        let speed = Alexa.getSlotValue(handlerInput.requestEnvelope, 'Speed');
        speed = Math.max(1, Math.min(100, parseInt(speed)));
        Util.putSessionAttribute(handlerInput, 'speed', speed);

        return handlerInput.responseBuilder
            .speak(`speed set to ${speed} percent.`)
            .reprompt("awaiting command")
            .getResponse();
    }
};

// Construct and send a custom directive to the connected gadget with
// data from the MoveIntent request.
const MoveIntentHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'IntentRequest'
            && Alexa.getIntentName(handlerInput.requestEnvelope) === 'MoveIntent';
    },
    handle: function (handlerInput) {
        const request = handlerInput.requestEnvelope;
        const direction = Alexa.getSlotValue(request, 'Direction');

        // Duration is optional, use default if not available
        const duration = Alexa.getSlotValue(request, 'Duration') || "2";

        // Get data from session attribute
        const attributesManager = handlerInput.attributesManager;
        const speed = attributesManager.getSessionAttributes().speed || "50";
        const endpointId = attributesManager.getSessionAttributes().endpointId || [];
        var reverse_direction = direction;
        if ( direction === "forward") {
            reverse_direction = "back";
        } else if (direction === "back") {
            reverse_direction = "forward";
        } 
        
        console.log("Orignal Direction:");
        console.log(direction);
        console.log("Changed Direction:");
        console.log(reverse_direction);

        // Construct the directive with the payload containing the move parameters
        const directive = Util.build(endpointId, NAMESPACE, NAME_CONTROL,
            {
                type: 'move',
                direction: reverse_direction,
                duration: duration,
                speed: speed
            });

        const speechOutput = (direction === "brake")
            ?  "Applying brake"
            : `${direction} ${duration} seconds at ${speed} percent speed`;

        return handlerInput.responseBuilder
            .speak(speechOutput)
            .reprompt("awaiting command")
            .addDirective(directive)
            .getResponse();
    }
};

// Construct and send a custom directive to the connected gadget with data from
// the SetCommandIntent request.
const SetCommandIntentHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'IntentRequest'
            && Alexa.getIntentName(handlerInput.requestEnvelope) === 'SetCommandIntent';
    },
    handle: function (handlerInput) {

        let command = Alexa.getSlotValue(handlerInput.requestEnvelope, 'Command');
        if (!command) {
            return handlerInput.responseBuilder
                .speak("Can you repeat that?")
                .reprompt("What was that again?").getResponse();
        }

        const attributesManager = handlerInput.attributesManager;
        let endpointId = attributesManager.getSessionAttributes().endpointId || [];
        let speed = attributesManager.getSessionAttributes().speed || "50";

        // Construct the directive with the payload containing the move parameters
        let directive = Util.build(endpointId, NAMESPACE, NAME_CONTROL,
            {
                type: 'command',
                command: command,
                speed: speed
            });

        return handlerInput.responseBuilder
            .speak(`command ${command} activated`)
            .reprompt("awaiting command")
            .addDirective(directive)
            .getResponse();
    }
};

// The SkillBuilder acts as the entry point for your skill, routing all request and response
// payloads to the handlers above. Make sure any new handlers or interceptors you've
// defined are included below. The order matters - they're processed top to bottom.
exports.handler = Alexa.SkillBuilders.custom()
    .addRequestHandlers(
        LaunchRequestHandler,
        SetSpeedIntentHandler,
        SetCommandIntentHandler,
        MoveIntentHandler,
        Common.HelpIntentHandler,
        Common.CancelAndStopIntentHandler,
        Common.SessionEndedRequestHandler,
        Common.IntentReflectorHandler, // make sure IntentReflectorHandler is last so it doesn't override your custom intent handlers
    )
    .addRequestInterceptors(Common.RequestInterceptor)
    .addErrorHandlers(
        Common.ErrorHandler,
    )
    .lambda();

Mission 3 code

Python
#!/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 json
import random
import threading

from enum import Enum
from agt import AlexaGadget

from ev3dev2.led import Leds
from ev3dev2.sound import Sound
from ev3dev2.motor import OUTPUT_A, OUTPUT_B, OUTPUT_C, MoveTank, SpeedPercent, MediumMotor

# 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 Direction(Enum):
    """
    The list of directional commands and their variations.
    These variations correspond to the skill slot values.
    """
    FORWARD = ['forward', 'forwards', 'go forward']
    BACKWARD = ['back', 'backward', 'backwards', 'go backward']
    LEFT = ['left', 'go left']
    RIGHT = ['right', 'go right']
    STOP = ['stop', 'brake']


class Command(Enum):
    """
    The list of preset commands and their invocation variation.
    These variations correspond to the skill slot values.
    """
    MOVE_CIRCLE = ['circle', 'spin']
    MOVE_SQUARE = ['square']
    PATROL = ['patrol', 'guard mode', 'sentry mode']
    FIRE_ONE = ['cannon', '1 shot', 'one shot']
    FIRE_ALL = ['all shot']


class MindstormsGadget(AlexaGadget):
    """
    A Mindstorms gadget that performs movement based on voice commands.
    Two types of commands are supported, directional movement and preset.
    """

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

        # Gadget state
        self.patrol_mode = False

        # Ev3dev initialization
        self.leds = Leds()
        self.sound = Sound()
        self.drive = MoveTank(OUTPUT_B, OUTPUT_C)
        self.weapon = MediumMotor(OUTPUT_A)

        # Start threads
        threading.Thread(target=self._patrol_thread, daemon=True).start()

    def on_connected(self, device_addr):
        """
        Gadget connected to the paired Echo device.
        :param device_addr: the address of the device we connected to
        """
        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 device_addr: the address of the device we disconnected from
        """
        self.leds.set_color("LEFT", "BLACK")
        self.leds.set_color("RIGHT", "BLACK")
        logger.info("{} disconnected from Echo device".format(self.friendly_name))

    def on_custom_mindstorms_gadget_control(self, directive):
        """
        Handles the Custom.Mindstorms.Gadget control directive.
        :param directive: the custom directive with the matching namespace and name
        """
        try:
            payload = json.loads(directive.payload.decode("utf-8"))
            print("Control payload: {}".format(payload), file=sys.stderr)
            control_type = payload["type"]
            if control_type == "move":

                # Expected params: [direction, duration, speed]
                self._move(payload["direction"], int(payload["duration"]), int(payload["speed"]))

            if control_type == "command":
                # Expected params: [command]
                self._activate(payload["command"])

        except KeyError:
            print("Missing expected parameters: {}".format(directive), file=sys.stderr)

    def _move(self, direction, duration: int, speed: int, is_blocking=False):
        """
        Handles move commands from the directive.
        Right and left movement can under or over turn depending on the surface type.
        :param direction: the move direction
        :param duration: the duration in seconds
        :param speed: the speed percentage as an integer
        :param is_blocking: if set, motor run until duration expired before accepting another command
        """
        print("Move command: ({}, {}, {}, {})".format(direction, speed, duration, is_blocking), file=sys.stderr)
        if direction in Direction.FORWARD.value:
            self.drive.on_for_seconds(SpeedPercent(speed), SpeedPercent(speed), duration, block=is_blocking)

        if direction in Direction.BACKWARD.value:
            self.drive.on_for_seconds(SpeedPercent(-speed), SpeedPercent(-speed), duration, block=is_blocking)

        if direction in (Direction.RIGHT.value + Direction.LEFT.value):
            self._turn(direction, speed)
            self.drive.on_for_seconds(SpeedPercent(speed), SpeedPercent(speed), duration, block=is_blocking)

        if direction in Direction.STOP.value:
            self.drive.off()
            self.patrol_mode = False

    def _activate(self, command, speed=50):
        """
        Handles preset commands.
        :param command: the preset command
        :param speed: the speed if applicable
        """
        print("Activate command: ({}, {})".format(command, speed), file=sys.stderr)
        if command in Command.MOVE_CIRCLE.value:
            self.drive.on_for_seconds(SpeedPercent(int(speed)), SpeedPercent(5), 12)

        if command in Command.MOVE_SQUARE.value:
            for i in range(4):
                self._move("right", 2, speed, is_blocking=True)

        if command in Command.PATROL.value:
            # Set patrol mode to resume patrol thread processing
            self.patrol_mode = True

        if command in Command.FIRE_ONE.value:
            self.weapon.on_for_rotations(SpeedPercent(100), 3)

        if command in Command.FIRE_ALL.value:
            self.weapon.on_for_rotations(SpeedPercent(100), 10)

    def _turn(self, direction, speed):
        """
        Turns based on the specified direction and speed.
        Calibrated for hard smooth surface.
        :param direction: the turn direction
        :param speed: the turn speed
        """
        if direction in Direction.LEFT.value:
            self.drive.on_for_seconds(SpeedPercent(0), SpeedPercent(speed), 2)

        if direction in Direction.RIGHT.value:
            self.drive.on_for_seconds(SpeedPercent(speed), SpeedPercent(0), 2)

    def _patrol_thread(self):
        """
        Performs random movement when patrol mode is activated.
        """
        while True:
            while self.patrol_mode:
                print("Patrol mode activated randomly picks a path", file=sys.stderr)
                direction = random.choice(list(Direction))
                duration = random.randint(1, 5)
                speed = random.randint(1, 4) * 25

                while direction == Direction.STOP:
                    direction = random.choice(list(Direction))

                # direction: all except stop, duration: 1-5s, speed: 25, 50, 75, 100
                self._move(direction.value[0], duration, speed)
                time.sleep(duration)
            time.sleep(1)


if __name__ == '__main__':

    gadget = MindstormsGadget()

    # Set LCD font and turn off blinking 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")

Credits

Hamza Chaudhary

Hamza Chaudhary

2 projects • 1 follower
Thanks to Amazon and Ikson.

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