Coach PolMisMantoArduinobeginer45
Published © GPL3+

GC: The robot with the power of voice interaction

GC is the new EV3 robot of the team GreekCodersK12. GC runs Python programs and interacts with Alexa.

AdvancedFull instructions providedOver 12 days250

Things used in this project

Hardware components

LEGO MindStorms LEGO®Education MINDSTORMS® EV3 Core Set
×1
LEGO MindStorms LEGO Education LME EV3 Expansion Set
×1
FLL 2018 Into Orbit Challenge 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

Visual Studio 2017
Microsoft Visual Studio 2017
Alexa Skills Kit
Amazon Alexa Alexa Skills Kit
Alexa Gadgets Toolkit
Amazon Alexa Alexa Gadgets Toolkit
Amazon Music Unlimited
balena etcher
EV3 Python ev3dev

Story

Read more

Schematics

mission01-ini file

Gadget settings for mission 01

Mission01

Mission 01 Video
EV3 reacts to the word Alexa

Mission02

EV3 robot dances STARWARS music

Mission03

Alexa skill Open Mindstorms.
GC listens to Alexa commands: Forward, Backward, Right, Move in a circle, move square, One shot

Mission04

Alexa Open mindstorms.. activate sentry.. fire one shot.. fire all shots

Code

mission-01

Python
Mission 01- Python file- EV3 connects with ALEXA- A welcome message from EV3 after connection - EV3 interacts with ALEXA
#!/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))
        
        from ev3dev2.sound import Sound
        sound = Sound()
        sound.speak ('Welcome to Python E v 3 alexa')

    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", "RED")

    # 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-02

Python
GC robot listens to Amazon music and dances
#!/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)  # change from -750 to 750
                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

                # add a dance finale
                self.right_motor.run_timed(speed_sp=-200, time_sp=2500)
                self.left_motor.run_timed(speed_sp= -200, time_sp=2500)  

                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) # change sign of motor_speed
            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")

mission-03-snippet- python code- circle-square

Python
Snippet from the code of move commands in mission 03
# A snippet from mission-03 for move commands

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']

# the move forward, move backward commands 

    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)

        

# the move in a circle, move square commands

    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)

 

mission04-common.js

Java
/*
 * 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.
*/
'use strict'

const Alexa = require('ask-sdk-core');

const HelpIntentHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'IntentRequest'
            && Alexa.getIntentName(handlerInput.requestEnvelope) === 'AMAZON.HelpIntent';
    },
    handle(handlerInput) {
        const speakOutput = 'You can say hello to me! How can I help?';

        return handlerInput.responseBuilder
            .speak(speakOutput)
            .reprompt(speakOutput)
            .getResponse();
    }
};
const CancelAndStopIntentHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'IntentRequest'
            && (Alexa.getIntentName(handlerInput.requestEnvelope) === 'AMAZON.CancelIntent'
                || Alexa.getIntentName(handlerInput.requestEnvelope) === 'AMAZON.StopIntent');
    },
    handle(handlerInput) {
        const speakOutput = 'Goodbye!';
        return handlerInput.responseBuilder
            .speak(speakOutput)
            .getResponse();
    }
};
const SessionEndedRequestHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'SessionEndedRequest';
    },
    handle(handlerInput) {
        // Any cleanup logic goes here.
        return handlerInput.responseBuilder.getResponse();
    }
};

// The intent reflector is used for interaction model testing and debugging.
// It will simply repeat the intent the user said. You can create custom handlers
// for your intents by defining them above, then also adding them to the request
// handler chain below.
const IntentReflectorHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'IntentRequest';
    },
    handle(handlerInput) {
        const intentName = Alexa.getIntentName(handlerInput.requestEnvelope);
        const speakOutput = `You just triggered ${intentName}`;

        return handlerInput.responseBuilder
            .speak(speakOutput)
            .reprompt("I don't understand this command, try again")
            .getResponse();
    }
};

// Generic error handling to capture any syntax or routing errors. If you receive an error
// stating the request handler chain is not found, you have not implemented a handler for
// the intent being invoked or included it in the skill builder below.
const ErrorHandler = {
    canHandle() {
        return true;
    },
    handle(handlerInput, error) {
        console.log(`~~~~ Error handled: ${error.stack}`);
        const speakOutput = `Sorry, I had trouble doing what you asked. Please try again.`;

        return handlerInput.responseBuilder
            .speak(speakOutput)
            .reprompt(speakOutput)
            .getResponse();
    }
};

// The request interceptor is used for request handling testing and debugging.
// It will simply log the request in raw json format before any processing is performed.
const RequestInterceptor = {
    process(handlerInput) {
        let { attributesManager, requestEnvelope } = handlerInput;
        let sessionAttributes = attributesManager.getSessionAttributes();

        // Log the request for debug purposes.
        console.log(`=====Request==${JSON.stringify(requestEnvelope)}`);
        console.log(`=========SessionAttributes==${JSON.stringify(sessionAttributes, null, 2)}`);
    }
};

module.exports = {
    HelpIntentHandler,
    CancelAndStopIntentHandler,
    SessionEndedRequestHandler,
    IntentReflectorHandler,
    ErrorHandler,
    RequestInterceptor
};

mission04-util.js

Java
/*
 * 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.
*/

'use strict';

const Https = require('https');
const AWS = require('aws-sdk');
const Escape = require('lodash/escape');

const s3SigV4Client = new AWS.S3({
    signatureVersion: 'v4'
});

/**
 * Get the authenticated URL to access the S3 Object. This URL expires after 60 seconds.
 * @param s3ObjectKey - the S3 object key
 * @returns {string} the pre-signed S3 URL
 */
exports.getS3PreSignedUrl = function getS3PreSignedUrl(s3ObjectKey) {

    const bucketName = process.env.S3_PERSISTENCE_BUCKET;
    return Escape(s3SigV4Client.getSignedUrl('getObject', {
        Bucket: bucketName,
        Key: s3ObjectKey,
        Expires: 60 // the Expires is capped for 1 minute
    }));
};

/**
 * Builds a directive to start the EventHandler.
 * @param token - a unique identifier to track the event handler
 * @param {number} timeout - the duration to wait before sending back the expiration
 * payload to the skill.
 * @param payload - the expiration json payload
 * @see {@link https://developer.amazon.com/docs/alexa-gadgets-toolkit/receive-custom-event-from-gadget.html#start}
 */
exports.buildStartEventHandler = function (token, timeout = 30000, payload)  {
    return {
        type: "CustomInterfaceController.StartEventHandler",
        token: token,
        expiration : {
            durationInMilliseconds: timeout,
            expirationPayload: payload
        }
    };
};

/**
 *
 * Builds a directive to stops the active event handler.
 * The event handler is identified by the cached token in the session attribute.
 * @param {string} handlerInput - the context from Alexa Service
 * @see {@link https://developer.amazon.com/docs/alexa-gadgets-toolkit/receive-custom-event-from-gadget.html#stop}
 */
exports.buildStopEventHandlerDirective = function (handlerInput) {

    let token = handlerInput.attributesManager.getSessionAttributes().token || '';
    return {
        "type": "CustomInterfaceController.StopEventHandler",
        "token": token
    }
};

/**
 * Build a custom directive payload to the gadget with the specified endpointId
 * @param {string} endpointId - the gadget endpoint Id
 * @param {string} namespace - the namespace of the skill
 * @param {string} name - the name of the skill within the scope of this namespace
 * @param {object} payload - the payload data
 * @see {@link https://developer.amazon.com/docs/alexa-gadgets-toolkit/send-gadget-custom-directive-from-skill.html#respond}
 */
exports.build = function (endpointId, namespace, name, payload) {
    // Construct the custom directive that needs to be sent
    // Gadget should declare the capabilities in the discovery response to
    // receive the directives under the following namespace.
    return {
        type: 'CustomInterfaceController.SendDirective',
        header: {
            name: name,
            namespace: namespace
        },
        endpoint: {
            endpointId: endpointId
        },
        payload
    };
};

/**
 * A convenience routine to add the a key-value pair to the session attribute.
 * @param handlerInput - the context from Alexa Service
 * @param key - the key to be added
 * @param value - the value be added
 */
exports.putSessionAttribute = function(handlerInput, key, value) {
    const attributesManager = handlerInput.attributesManager;
    let sessionAttributes = attributesManager.getSessionAttributes();
    sessionAttributes[key] = value;
    attributesManager.setSessionAttributes(sessionAttributes);
};


/**
 * To get a list of all the gadgets that meet these conditions,
 * Call the Endpoint Enumeration API with the apiEndpoint and apiAccessToken to
 * retrieve the list of all connected gadgets.
 *
 * @param {string} apiEndpoint - the Endpoint API url
 * @param {string} apiAccessToken  - the token from the session object in the Alexa request
 * @see {@link https://developer.amazon.com/docs/alexa-gadgets-toolkit/send-gadget-custom-directive-from-skill.html#call-endpoint-enumeration-api}
 */
exports.getConnectedEndpoints = function(apiEndpoint, apiAccessToken) {

    // The preceding https:// need to be stripped off before making the call
    apiEndpoint = (apiEndpoint || '').replace('https://', '');

    return new Promise(((resolve, reject) => {

        const options = {
            host: apiEndpoint,
            path: '/v1/endpoints',
            method: 'GET',
            headers: {
                'Content-Type': 'application/json',
                'Authorization': 'Bearer ' + apiAccessToken
            }
        };

        const request = Https.request(options, (response) => {
            response.setEncoding('utf8');
            let returnData = '';
            response.on('data', (chunk) => {
                returnData += chunk;
            });

            response.on('end', () => {
                resolve(JSON.parse(returnData));
            });

            response.on('error', (error) => {
                reject(error);
            });
        });
        request.end();
    }));
};

mission 04-package.json

JSON
{
  "name": "agt-mindstorms",
  "version": "1.1.0",
  "description": "A sample skill demonstrating how to use AGT with Lego Mindstorms",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "Amazon Alexa",
  "license": "ISC",
  "dependencies": {
    "ask-sdk-core": "^2.6.0",
    "ask-sdk-model": "^1.18.0",
    "aws-sdk": "^2.326.0",
    "request": "^2.81.0",
    "lodash": "^4.17.11"
  }
}

mission04-index.js

Java
index.js with changes for ultrasonic distance => if (name === 'Proximity')
/*
 * 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 skill sample demonstrates how to send directives and receive events from an Echo connected gadget.
// This skill uses 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 audio tag to include background music
const BG_MUSIC = '<audio src="soundbank://soundlibrary/ui/gameshow/amzn_ui_sfx_gameshow_waiting_loop_30s_01"></audio>';

// 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) {

        const request = handlerInput.requestEnvelope;
        const { apiEndpoint, apiAccessToken } = request.context.System;
        const 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
        const endpointId = apiResponse.endpoints[0].endpointId || [];
        Util.putSessionAttribute(handlerInput, 'endpointId', endpointId);

        // Set skill duration to 5 minutes (ten 30-seconds interval)
        Util.putSessionAttribute(handlerInput, 'duration', 10);

        // Set the token to track the event handler
        const token = handlerInput.requestEnvelope.request.requestId;
        Util.putSessionAttribute(handlerInput, 'token', token);

        let speechOutput = "Welcome, voice interface activated";
        return handlerInput.responseBuilder
            .speak(speechOutput + BG_MUSIC)
            .addDirective(Util.buildStartEventHandler(token,60000, {}))
            .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);

        let speechOutput = `speed set to ${speed} percent.`;
        return handlerInput.responseBuilder
            .speak(speechOutput + BG_MUSIC)
            .getResponse();
    }
};

// Construct and send a custom directive to the connected gadget with
// data from the MoveIntent.
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 || [];

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

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

        return handlerInput.responseBuilder
            .speak(speechOutput + BG_MUSIC)
            .addDirective(directive)
            .getResponse();
    }
};

// Construct and send a custom directive to the connected gadget with data from
// the SetCommandIntent.
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?")
                .withShouldEndSession(false)
                .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
            });

        let speechOutput = `command ${command} activated`;
        if (command === 'sentry' || command === 'sentry mode') {
            speechOutput = '';
        }
        return handlerInput.responseBuilder
            .speak(speechOutput + BG_MUSIC)
            .addDirective(directive)
            .getResponse();
    }
};

const EventsReceivedRequestHandler = {
    // Checks for a valid token and endpoint.
    canHandle(handlerInput) {
        let { request } = handlerInput.requestEnvelope;
        console.log('Request type: ' + Alexa.getRequestType(handlerInput.requestEnvelope));
        if (request.type !== 'CustomInterfaceController.EventsReceived') return false;

        const attributesManager = handlerInput.attributesManager;
        let sessionAttributes = attributesManager.getSessionAttributes();
        let customEvent = request.events[0];

        // Validate event token
        if (sessionAttributes.token !== request.token) {
            console.log("Event token doesn't match. Ignoring this event");
            return false;
        }

        // Validate endpoint
        let requestEndpoint = customEvent.endpoint.endpointId;
        if (requestEndpoint !== sessionAttributes.endpointId) {
            console.log("Event endpoint id doesn't match. Ignoring this event");
            return false;
        }
        return true;
    },
    handle(handlerInput) {

        console.log("== Received Custom Event ==");
        let customEvent = handlerInput.requestEnvelope.request.events[0];
        let payload = customEvent.payload;
        let name = customEvent.header.name;

        let speechOutput;
        if (name === 'Proximity') {
            let distance = parseInt(payload.distance);
            if (distance < 400.0) {
                let speechOutput = "Intruder detected! What would you like to do?";
                return handlerInput.responseBuilder
                    .speak(speechOutput, "REPLACE_ALL")
                    .withShouldEndSession(false)
                    .getResponse();
            }
        } else if (name === 'Sentry') {
            if ('fire' in payload) {
                speechOutput = "Threat eliminated";
            }

        } else if (name === 'Speech') {
            speechOutput = payload.speechOut;

        } else {
            speechOutput = "Event not recognized. Awaiting new command.";
        }
        return handlerInput.responseBuilder
            .speak(speechOutput + BG_MUSIC, "REPLACE_ALL")
            .getResponse();
    }
};
const ExpiredRequestHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'CustomInterfaceController.Expired'
    },
    handle(handlerInput) {
        console.log("== Custom Event Expiration Input ==");

        // Set the token to track the event handler
        const token = handlerInput.requestEnvelope.request.requestId;
        Util.putSessionAttribute(handlerInput, 'token', token);

        const attributesManager = handlerInput.attributesManager;
        let duration = attributesManager.getSessionAttributes().duration || 0;
        if (duration > 0) {
            Util.putSessionAttribute(handlerInput, 'duration', --duration);

            // Extends skill session
            const speechOutput = `${duration} minutes remaining.`;
            return handlerInput.responseBuilder
                .addDirective(Util.buildStartEventHandler(token, 60000, {}))
                .speak(speechOutput + BG_MUSIC)
                .getResponse();
        }
        else {
            // End skill session
            return handlerInput.responseBuilder
                .speak("Skill duration expired. Goodbye.")
                .withShouldEndSession(true)
                .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,
        EventsReceivedRequestHandler,
        ExpiredRequestHandler,
        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-04

Python
mission 04 python file for sentry mode
#!/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_D, OUTPUT_B, OUTPUT_C, MoveTank, SpeedPercent, MediumMotor
from ev3dev2.sensor.lego import  UltrasonicSensor


# 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', 'halt']


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


class EventName(Enum):
    """
    The list of custom event name sent from this gadget
    """
    SENTRY = "Sentry"
    PROXIMITY = "Proximity"
    SPEECH = "Speech"


class MindstormsGadget(AlexaGadget):
    """
    A Mindstorms gadget that can perform bi-directional interaction with an Alexa skill.
    """

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

        # Robot state
        self.sentry_mode = False
        self.patrol_mode = False

        # Connect two large motors on output ports B and C
        self.drive = MoveTank(OUTPUT_B, OUTPUT_C)
        self.weapon = MediumMotor(OUTPUT_D)
        self.sound = Sound()
        self.leds = Leds()
        self.us = UltrasonicSensor() # initialize ultrasonic

        # Start threads
        threading.Thread(target=self._patrol_thread, daemon=True).start()
        threading.Thread(target=self._proximity_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.SENTRY.value:
            self.sentry_mode = True
            self._send_event(EventName.SPEECH, {'speechOut': "Sentry mode activated"})

            # Perform Shuffle posture
            self.drive.on_for_seconds(SpeedPercent(80), SpeedPercent(-80), 0.2)
            time.sleep(0.3)
            self.drive.on_for_seconds(SpeedPercent(-40), SpeedPercent(40), 0.2)

            self.leds.set_color("LEFT", "YELLOW", 1)
            self.leds.set_color("RIGHT", "YELLOW", 1)

        if command in Command.FIRE_ONE.value:
            print("Fire one", file=sys.stderr)

            self.weapon.on_for_rotations(SpeedPercent(100), 0.60)
            self.weapon.on_for_rotations(SpeedPercent(-100), 0.60)

            self._send_event(EventName.SENTRY, {'fire': 1})
            self.sentry_mode = False
            print("Sent sentry event - 1 shot, alarm reset", file=sys.stderr)
            self.leds.set_color("LEFT", "GREEN", 1)
            self.leds.set_color("RIGHT", "GREEN", 1)

        if command in Command.FIRE_ALL.value:
            print("Fire all", file=sys.stderr)

            self.weapon.on_for_rotations(SpeedPercent(100), 0.60)
            self.weapon.on_for_rotations(SpeedPercent(-100), 0.60)
            self.sound.speak('Bang bang bang')     

            self._send_event(EventName.SENTRY, {'fire': 3})
            self.sentry_mode = False
            print("sent sentry event - 3 shots, alarm reset", file=sys.stderr)
            self.leds.set_color("LEFT", "GREEN", 1)
            self.leds.set_color("RIGHT", "GREEN", 1)

    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 _send_event(self, name: EventName, payload):
        """
        Sends a custom event to trigger a sentry action.
        :param name: the name of the custom event
        :param payload: the sentry JSON payload
        """
        self.send_custom_event('Custom.Mindstorms.Gadget', name.value, payload)

    def _proximity_thread(self):
        """
        Monitors the distance between the robot and an obstacle when sentry mode is activated.
        If the minimum distance is breached, send a custom event to trigger action on
        the Alexa skill.
        """
        count = 0
        while True:
            while self.sentry_mode:
                distance = self.us.value()
                print("Proximity: {}".format(distance), file=sys.stderr)
                count = count + 1 if distance < 400.0 else 0
                if count > 3:
                    print("Proximity breached. Sending event to skill", file=sys.stderr)
                    self.leds.set_color("LEFT", "RED", 1)
                    self.leds.set_color("RIGHT", "RED", 1)

                    self._send_event(EventName.PROXIMITY, {'distance': distance})
                    self.sentry_mode = False

                time.sleep(0.2)
            time.sleep(1)

    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

Coach PolMis

Coach PolMis

1 project • 3 followers
EdTech, Computer Science and Math teacher MSc. MEd. Founder of the coding club GreekCodersK12 in 2015. https://greekcodersk12.school.blog/
Manto

Manto

1 project • 1 follower
Arduinobeginer45

Arduinobeginer45

1 project • 0 followers

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