WEBVTT 00:00.200 --> 00:06.530 Let's conclude the voice interaction model of our Alexa skill with the robot by adding new, more handlers 00:06.530 --> 00:08.600 for each of the skills intent. 00:08.750 --> 00:14.870 So once again, we refer to the documentation that Amazon provides to the Python skill developers. 00:14.870 --> 00:19.430 So go to this link here that I also live in the description of this lesson. 00:19.910 --> 00:26.660 So here in the developing your first skill this time let's copy the second intent. 00:26.660 --> 00:28.580 So this one we have already implemented. 00:28.610 --> 00:30.080 Let's copy the second one. 00:30.080 --> 00:32.780 So the hello world intent handler. 00:32.840 --> 00:36.020 So let's copy this one and let's paste it. 00:36.020 --> 00:37.550 So in our script. 00:37.550 --> 00:44.060 So in the Arduino bot remote then in the Arduino bot remote folder and in the Alexa interface. 00:44.060 --> 00:50.570 So here below the launch request handler, let's paste the code that we have just copied. 00:50.720 --> 00:55.490 So let's add one more space here to improve the readability of the code. 00:55.490 --> 00:59.330 And now let's first change the name of this class into. 01:00.370 --> 01:06.760 So this one let's call peak intent handler. 01:06.880 --> 01:12.640 And let's also change the name of the intent for which the functionalities in this class will be executed. 01:12.640 --> 01:15.880 And so we want this class to be executed when the. 01:17.980 --> 01:20.290 Peak intent is triggered. 01:20.290 --> 01:26.830 So when the Alexa assistant sends us a message in which it's triggering the peak intent. 01:27.430 --> 01:30.130 In this case let's also change the response. 01:30.130 --> 01:34.870 So here that the voice assistant will pronounce when we activate this intent. 01:35.080 --> 01:41.680 And let's set this one to okay I'm moving. 01:42.040 --> 01:49.540 So when we activate this intent so the peak intent by saying for example the phrase pick up that pen 01:49.540 --> 01:54.700 or pick that pen, then Alexa will respond with this phrase here. 01:55.120 --> 01:57.550 Let's also change the name of the simple card. 01:57.550 --> 01:59.260 So here to be. 02:00.540 --> 02:01.140 peak. 02:01.860 --> 02:04.980 And now, before moving on to defining the next handler. 02:05.010 --> 02:12.000 Remember to register this handler in the skill builder using the add request handler function. 02:12.540 --> 02:18.270 So here basically let's copy this line and let's paste it. 02:18.270 --> 02:23.100 And now we want to register also this handler here. 02:23.100 --> 02:25.470 So the peak intent handler. 02:25.830 --> 02:30.960 Next let's create another handler so we can copy all of these. 02:31.620 --> 02:34.230 And we can paste it here below. 02:34.380 --> 02:36.120 And let's call this one. 02:36.510 --> 02:38.850 So here let's change the name of this class. 02:38.850 --> 02:42.630 And let's call it sleep intent handler. 02:42.630 --> 02:48.570 And this class will be activated when a message is received from the Amazon Alexa assistant. 02:48.600 --> 02:51.750 That is of type sleep intent. 02:51.750 --> 02:59.750 So when this intent is triggered by the Alexa assistant, we want it to say the phrase Okay. 03:01.550 --> 03:02.840 See you later. 03:03.920 --> 03:07.970 And let's also change the name of this simple card to zlib. 03:08.060 --> 03:11.150 And as always, we need to register this handler. 03:11.150 --> 03:12.860 So let's copy this one. 03:13.370 --> 03:17.690 And let's register now the sleep intent handler. 03:19.430 --> 03:23.090 And now let's define also the handler for the wake intent. 03:23.120 --> 03:26.270 Again we can copy this class here. 03:27.230 --> 03:29.720 And we can paste it here. 03:29.720 --> 03:32.600 And let's change the name of the class into. 03:34.970 --> 03:37.040 Wake intent handler. 03:37.040 --> 03:43.700 And this class is going to be triggered when the wake intent is triggered by the Amazon Alexa. 03:44.360 --> 03:53.420 And we want the assistant to respond with the phrase I am ready. 03:54.590 --> 03:55.280 Okay. 03:55.280 --> 03:59.920 And let's also change here the name of the simple card to be the wake. 04:00.070 --> 04:05.200 And as well let's register also this new handler. 04:05.200 --> 04:07.450 So the wake intent handler. 04:07.960 --> 04:09.670 So let's paste it here. 04:10.060 --> 04:13.840 Now with this we have added the handlers for all the functionalities. 04:13.840 --> 04:19.210 So for all the intent that we created in the previous lessons for the Alexa skill. 04:19.210 --> 04:24.760 So here we have managed all the handlers that Alexa can send to our script. 04:24.760 --> 04:26.320 So to our web service. 04:26.320 --> 04:30.310 So the communication will start always with the launch request. 04:30.310 --> 04:36.550 And then depending on what we say so on what we ask to the assistant it will trigger the pick intent 04:36.580 --> 04:39.460 or the sleep intent or the wake intent. 04:40.480 --> 04:45.850 Now let's also add one last handler, this time for cases when the command enters. 04:45.850 --> 04:52.120 The intent request that Alexa sent to us doesn't fall into any of the previous category. 04:52.480 --> 04:57.870 This typically happens when we activate the skill and send a command to the robot, but Alexa doesn't 04:57.870 --> 04:59.850 understand the command correctly. 05:00.450 --> 05:06.450 So let's go back here to the documentation, and let's add a handler to manage exceptions. 05:06.450 --> 05:16.440 And we can copy this still from this documentation, if we go the exception handler section here, we 05:16.440 --> 05:17.550 can copy this one. 05:17.550 --> 05:24.810 The all exception handler that as the name says will catch any exception and so will manage any command 05:24.840 --> 05:27.600 that was not properly understood by Alexa. 05:28.260 --> 05:31.710 So let's copy this one and let's paste it here. 05:32.670 --> 05:34.530 Let's move this one. 05:34.530 --> 05:38.070 So the import at the beginning of the file. 05:38.100 --> 05:40.110 So let's move it here. 05:41.160 --> 05:47.280 And now as I said this handler will be triggered whenever none of the previous one is activated. 05:47.280 --> 05:56.270 And so when it is activated we want the voice assistant to say so let's make it say the phrase Sorry. 05:59.060 --> 06:02.060 I didn't. 06:04.550 --> 06:05.900 Understand? 06:07.400 --> 06:10.850 Could you repeat? 06:11.270 --> 06:14.750 So whenever Alexa is not able to understand a command. 06:14.780 --> 06:21.380 So whenever the command that we have sent doesn't fall into any of these categories, it will respond 06:21.740 --> 06:22.820 with this phrase here. 06:22.820 --> 06:24.890 So sorry, I didn't understand. 06:24.920 --> 06:26.150 Could you repeat. 06:26.450 --> 06:32.060 And now also we need to register this one so we can register it here. 06:33.050 --> 06:36.830 So let's use the Skill builder. 06:36.830 --> 06:39.530 And on this one let's use the function this time. 06:39.560 --> 06:42.590 Add exception handler. 06:42.590 --> 06:44.300 So we can see that there is a difference. 06:44.300 --> 06:51.980 So in order to register a normal handler so an event handler we use the add request handler function 06:51.980 --> 06:54.290 instead in order to manage the exceptions. 06:54.290 --> 07:00.310 So in order to register an exception handler or use the function add exception handler. 07:00.310 --> 07:02.410 And so let's register this class. 07:03.490 --> 07:06.490 So the all exception handler class. 07:06.490 --> 07:10.870 With this we have completed our voice interaction model with the assistant. 07:10.870 --> 07:16.900 And we have configured not only the responses that the assistant will give upon receiving a known command, 07:16.930 --> 07:21.910 but also the response for an unclear or unrecognized command. 07:22.630 --> 07:28.570 If you notice so far, this is a regular Python script, and in fact we started in the previous lesson 07:28.570 --> 07:30.190 with the command Python. 07:30.190 --> 07:36.940 And this actually doesn't use any element of the CLP library and thus is not integrating. 07:36.940 --> 07:39.370 So it is not communicating with Ros2. 07:39.790 --> 07:45.760 Now it's time to integrate this script with Ros2 and make it send a goal to the action server, which 07:45.760 --> 07:51.640 we called Task Server, upon receiving a specific voice command to do so. 07:51.640 --> 08:03.240 Let's start by importing the CLP library and as always from the CLP library from the node modules. 08:03.270 --> 08:07.470 Let's import the node class to create our Ros2 node. 08:07.680 --> 08:13.530 And now, since we want to send a goal to the task server, which we implemented as a Ros2 action server, 08:13.530 --> 08:15.420 we need also to create an action client. 08:15.420 --> 08:24.900 Of course for this again, let's also import from the CLP library and this time from the action module. 08:24.990 --> 08:28.380 Let's import the action client. 08:28.650 --> 08:31.320 And now let's use it to create a new class. 08:31.320 --> 08:33.840 So a new instance of this action client. 08:33.840 --> 08:43.410 So here let's create a new object a new variable called action client as an instance of the action client 08:43.410 --> 08:44.130 class. 08:44.190 --> 08:47.550 And to this one we need to pass the instance of the node. 08:47.550 --> 08:51.030 So the ros2 node that hosts the action client. 08:51.030 --> 08:53.840 And so let's create simply a new node. 08:53.840 --> 08:55.460 So a new Ross two node. 08:55.460 --> 09:00.470 And let's call this one Alexa interface. 09:00.470 --> 09:05.720 Next, for the creation of the action client, we also need to specify the message type. 09:05.720 --> 09:10.700 So the interface that the action client should use for the communication with the server. 09:11.060 --> 09:19.070 This is defined within the Arduino bot messages package and within the action folder. 09:19.100 --> 09:25.940 We defined this one in the Arduino bot task interface. 09:25.940 --> 09:34.490 And so now let's define that this action client is going to use the Arduino bot task interface. 09:34.490 --> 09:37.100 And also that this has to communicate. 09:37.100 --> 09:41.750 So the name of the action server is the task server. 09:41.750 --> 09:49.220 So we want this one to be a client of the server called task Server that uses the interface Arduino 09:49.220 --> 09:50.120 bot task. 09:50.150 --> 09:53.470 With this we have created our action client. 09:53.770 --> 09:58.630 Now we need to keep our ros2 node running so that we can keep this node active. 09:58.630 --> 10:03.790 And so we can send goal to the action server upon receiving a new command from Alexa. 10:03.820 --> 10:08.590 So within of these handlers since in the main function of this script. 10:08.590 --> 10:16.540 So this one here we are already keeping the main application thread busy with the flask web service. 10:16.540 --> 10:22.480 For the interface with Alexa, we are going to create the interface with Ros2 in a separate thread in 10:22.480 --> 10:24.610 order to allow both the functionalities. 10:24.610 --> 10:30.250 So the Alexa interface, this one through the web service, and also the Ros2 node interface through 10:30.250 --> 10:32.710 the action client to run in parallel. 10:32.710 --> 10:38.380 So we will enable these two applications to run in parallel by creating a separate thread. 10:38.590 --> 10:42.310 To do this in Python, let's import another library. 10:42.820 --> 10:48.250 So let's import the threading library. 10:48.250 --> 10:50.740 And from this one let's create a new thread. 10:50.740 --> 10:57.300 So from the trading library, let's create a new thread. 10:57.300 --> 11:01.440 And in this thread we simply want to keep our Ros2 node running. 11:01.440 --> 11:04.980 And so we can achieve this by using a lambda function. 11:04.980 --> 11:06.810 So target. 11:06.810 --> 11:11.970 Let's use a lambda function that is an anonymous function. 11:11.970 --> 11:17.760 And this simply says rcl pi dot init. 11:17.760 --> 11:21.240 So we are initializing the ros2 node. 11:21.240 --> 11:25.200 And then let's also start this thread. 11:25.200 --> 11:31.590 So which means that we start keeping the Ros2 node running using the start function of the thread. 11:32.430 --> 11:36.270 Now everything is set also for the communication with Ros2. 11:36.270 --> 11:38.940 So between this script and Ros2. 11:38.940 --> 11:42.120 And so with the task server that is available in Ros2. 11:42.270 --> 11:45.330 And now we can start using this variable here. 11:45.330 --> 11:48.450 So the action client to send goal to the task server. 11:48.450 --> 11:55.340 And so to move the robot every time the web service saw the flask web service receives a new request 11:55.340 --> 11:57.320 from the Alexa assistant. 11:58.100 --> 12:00.080 Let's start with the first handler. 12:00.080 --> 12:03.050 So this one the launch request handler. 12:03.470 --> 12:07.010 When this one is activated, we are going to send a new goal. 12:07.010 --> 12:15.020 And so here before the return statement let's create a new variable called goal that belongs to the 12:15.020 --> 12:17.000 Arduino bot task interface. 12:17.540 --> 12:19.460 And this is a goal message. 12:19.460 --> 12:25.130 And in this case, since we are in the intent that handles the activation of the robot with Alexa, 12:25.130 --> 12:31.190 we simply want the robot to execute the task number zero, which if you remember, is the one that moves 12:31.190 --> 12:32.780 the arm to the home position. 12:32.780 --> 12:35.990 So to the default position and opens the gripper. 12:36.110 --> 12:43.340 So on the goal object, let's set the task number to be the task zero. 12:43.340 --> 12:45.320 So we want to execute the task at zero. 12:45.410 --> 12:54.370 And then let's simply send this goal to the action server by using the action client descent goal async. 12:54.370 --> 12:56.830 And so let's send the goal message. 12:56.890 --> 12:59.800 We can do the same for all the other handlers. 12:59.800 --> 13:03.730 So let's copy this goal here. 13:03.730 --> 13:06.070 And now for the pick handler. 13:06.070 --> 13:12.940 So still here before returning from this function here let's just change the task number. 13:12.940 --> 13:19.120 And so in this case as we are requesting the execution of the pick intent, we want the robot to execute 13:19.120 --> 13:25.570 the task number one that if you remember, corresponds to move the robot to a hypothetical pick position 13:25.570 --> 13:27.580 and also closes the gripper. 13:28.900 --> 13:34.240 Then let's paste it again also here within the slip handler. 13:34.240 --> 13:40.330 And in this case we want the robot to perform the task number two that, if you remember, corresponds 13:40.330 --> 13:43.240 to a hypothetical rest position of the robot. 13:43.240 --> 13:46.570 And finally for the wake intent handler. 13:46.570 --> 13:49.110 So still here before Or returning. 13:49.500 --> 13:52.740 Let's execute instead the task number zero. 13:52.740 --> 13:54.990 So let's still execute the task number zero. 13:55.020 --> 14:01.260 Since we are in the wake intent handler and the task number zero brings the robot to the on position 14:01.800 --> 14:08.070 with this, for each command that we receive from the Amazon Alexa assistant, we have encoded a behavior 14:08.070 --> 14:08.940 of the robot. 14:08.940 --> 14:14.040 And so we are sending a goal to the robot that moves it in a particular position. 14:14.820 --> 14:17.580 Let's conclude this lesson by adding this node. 14:17.580 --> 14:23.970 So the Alexa interface to the launch file that starts all the functionalities that we developed in this 14:23.970 --> 14:24.720 package here. 14:24.720 --> 14:30.390 So in the Arduino bot remote package and this is the launch file that we have created and that we have 14:30.390 --> 14:33.420 called remote interface launch dot Pi. 14:33.450 --> 14:42.990 So here after the task server let's also start the Alexa interface node. 14:43.020 --> 14:45.900 So also this one is an instance of the node class. 14:45.930 --> 14:53.330 And now from the Package that is the Arduino bot remote package. 14:53.510 --> 14:55.790 We want to start the executable. 14:58.490 --> 14:59.660 That is called. 14:59.660 --> 15:03.170 So this one here the Alexa interface. 15:06.980 --> 15:07.550 Dot pi. 15:07.580 --> 15:08.270 Perfect. 15:08.300 --> 15:11.150 And we can also set a parameter. 15:12.020 --> 15:13.460 Actually this is a list. 15:13.550 --> 15:16.550 And we only just need to set the parameter. 15:16.580 --> 15:19.220 Use sim time. 15:19.220 --> 15:21.290 And we can use this variable here. 15:21.290 --> 15:25.040 So the is sim variable that will contain. 15:25.070 --> 15:28.010 So the value of this argument here. 15:28.010 --> 15:30.740 And so that will be either true if we are using. 15:30.740 --> 15:36.500 So if we are launching this launch file for the simulated robot or it will be false if we are using 15:36.500 --> 15:38.270 it for the real robot. 15:38.300 --> 15:39.200 Perfect. 15:39.200 --> 15:42.200 So with this one we have created a new node. 15:42.200 --> 15:47.770 And now in order to start it when this launch file is started, we need to add it here. 15:47.770 --> 15:50.380 So in the launch description list. 15:50.530 --> 15:51.520 Perfect. 15:51.520 --> 15:54.850 Then once we have added this node we also need to install it. 15:54.850 --> 16:00.100 So we need to install the Alexa interface dot pi here within the cmake list dot. 16:00.130 --> 16:01.330 TXT file. 16:01.330 --> 16:07.930 And actually in the install instructions here where we have already installed the task server dot pi. 16:08.020 --> 16:16.990 We can copy this command and we can paste it in order to install also the Alexa interface dot pi. 16:17.020 --> 16:19.510 So this node here perfect. 16:19.510 --> 16:21.160 So we can save also this file. 16:21.160 --> 16:22.210 And that's it. 16:22.240 --> 16:28.540 In the next lesson we're going to integrate all the functionalities that we have started here in the 16:28.540 --> 16:32.380 Arduino bot remote interface in the software architecture. 16:32.380 --> 16:38.500 So in the entire bring up package of the robot so that we will be able to start all the functionalities 16:38.500 --> 16:46.270 of the robot and to control our robot sending voice commands with Alexa using a single launch file.