WEBVTT 00:00.230 --> 00:06.200 In this laboratory lesson, we will apply everything we have learned so far in the course to visualize 00:06.200 --> 00:08.750 the Erdf model of the robot in RV's. 00:09.110 --> 00:16.310 To do this, we will use the Ros two parameters to configure some nodes that allows us to publish the 00:16.310 --> 00:18.410 Erdf model within some Ros. 00:18.410 --> 00:25.070 Two topics where Arviz will read the information needed to display the robot so including its links 00:25.070 --> 00:27.980 and joints in its graphical interface. 00:28.220 --> 00:33.140 So let's start by opening a new terminal and let's go to the workspace. 00:33.290 --> 00:34.980 Let's source it. 00:35.000 --> 00:38.120 So let's source the setup dot bash file. 00:38.360 --> 00:42.890 And now let's start by running the robot estate publisher node. 00:43.010 --> 00:53.360 So with the Ros two run command and from the robot state publisher package, let's start the robot state 00:53.360 --> 00:54.560 publisher node. 00:54.860 --> 01:01.590 This node has discussed in the theoretical lessons is a general purpose node that is developed to publish 01:01.590 --> 01:05.760 the RDF model of any robot within our Ros two topic. 01:06.150 --> 01:11.070 Therefore we need to configure it to publish the RDF model of our robot. 01:11.280 --> 01:15.530 So let's assign a value to a parameter that this node offers. 01:15.540 --> 01:23.970 And so as we learned in the previous lesson, to assign a parameter to a node, we use the Ros args 01:24.120 --> 01:29.280 and then minus P to assign a value to the parameter robot 01:31.560 --> 01:32.760 description. 01:33.000 --> 01:41.490 And so since we used the exact format to write the RDF model of our robot, but actually still the official 01:41.490 --> 01:50.910 accepted format for modeling robots is Erdf in Ros two, we first need to convert the model into a plain 01:50.910 --> 01:55.680 Erdf model before passing it to the robot description parameter. 01:56.070 --> 01:59.670 To do so, we can use a small trick, let's say. 01:59.670 --> 02:06.540 And so we can use a command within the parentheses and the command is. 02:07.500 --> 02:14.700 And then to this one we need to pass the directory of the Erdf model, which in my case is located in 02:14.700 --> 02:20.340 OLM, Alien Arduino Bot Workspace. 02:20.950 --> 02:26.520 And then it is in the source folder in the Arduino bot. 02:28.760 --> 02:38.430 Description in the DF and the model is called Arduino bot dot Urdf dot Zarco. 02:38.500 --> 02:47.920 So you have to substitute this directory here with the directory on your PC of the Arduino bot Urdf 02:48.220 --> 02:49.390 Hexaco model. 02:49.570 --> 02:54.100 So let's press enter and now we can leave this node up and running. 02:54.100 --> 03:00.250 So basically we can leave this node publishing the model of the robot within a certain topic. 03:00.640 --> 03:02.650 Now let's split the terminal. 03:02.650 --> 03:07.960 So let's open a new window and here let's again source the workspace. 03:08.530 --> 03:16.960 So the file setup dot bash and let's start a new node with the command Ros to run and this time from 03:16.960 --> 03:23.200 the joint state publish GUI package. 03:23.200 --> 03:27.370 Let's start the joint state publisher, GUI node. 03:27.400 --> 03:35.170 So let's press enter and this starts a graphical interface with some sliders which corresponds to all 03:35.170 --> 03:41.800 the movable joints of our robot which we can use then to move around our urdf model. 03:42.160 --> 03:49.660 So first, in order to see our robot moving, we need to launch our So still opening a new terminal. 03:49.750 --> 03:51.820 Let's again source it. 03:54.280 --> 03:58.990 And now let's run our RVs as if it was a normal Ros two node. 03:59.020 --> 04:00.940 So, Ros to run. 04:01.120 --> 04:04.000 And from the RVs to package. 04:04.000 --> 04:06.280 Let's start RV two. 04:07.600 --> 04:08.200 Here. 04:08.200 --> 04:10.060 This is the RV's window. 04:10.060 --> 04:16.870 And as a first step, as you can see here, we have an error saying that the global status so the fixed 04:16.870 --> 04:22.690 frame map doesn't exist because our first frame was the frame world. 04:22.720 --> 04:28.030 So let's change this one to be the frame world, the first frame of our model. 04:28.740 --> 04:33.120 Now everything is fine and we can add some visualization. 04:33.120 --> 04:37.160 So in order to visualize the links that make up the robot. 04:37.170 --> 04:41.820 And so let's click on Add and let's visualize the TF. 04:42.030 --> 04:43.860 So let's press enter. 04:43.860 --> 04:49.290 And this message contains the position and the orientation of all the links of the robot. 04:49.290 --> 04:55.530 And this one is published by the robot state publisher node, which here we left running. 04:55.530 --> 04:57.660 So it is still in execution. 04:57.960 --> 05:04.410 And now we can also display the robot meshes that are associated with each of these links. 05:04.410 --> 05:06.450 So this is just the structure. 05:06.540 --> 05:14.430 In order to visualize also the meshes, let's add a new plugin and this one is the robot model. 05:14.430 --> 05:16.260 So let's press Enter. 05:16.260 --> 05:23.610 And this plugin basically is subscribed to a topic where the robot description is published and it uses 05:23.610 --> 05:25.620 this topic to display the meshes. 05:25.890 --> 05:29.080 So let's change the name of the topic here. 05:29.080 --> 05:36.100 So here the description is topic and we need to check the robot description. 05:36.100 --> 05:37.870 So let's press enter. 05:37.870 --> 05:43.630 And now we can see that the meshes of the robot are all in place. 05:44.480 --> 05:52.040 Also, we can see that if we take the joint state publisher, so this window here and we move these 05:52.040 --> 05:52.880 sliders. 05:53.970 --> 06:00.210 The robot is moving accordingly so we can move all the joints. 06:01.860 --> 06:04.860 And also we can open and close the gripper. 06:06.160 --> 06:08.530 Before closing this window. 06:08.530 --> 06:10.960 Let's save the current configuration. 06:10.960 --> 06:16.450 So let's save the current configuration in which we have added the visualization of the TF plugin and 06:16.450 --> 06:22.300 the robot model so that the next time that we want to visualize this model, we don't have to add them 06:22.300 --> 06:23.110 manually. 06:23.290 --> 06:30.460 So let's go to file save config as and then let's go into our workspace. 06:30.670 --> 06:38.860 So here in the source folder in the Arduino bot description and here let's create a new folder called 06:39.820 --> 06:40.660 RVs. 06:40.780 --> 06:48.820 And within this folder let's call this visualization display dot RVs. 06:48.970 --> 06:51.130 So let's save this file. 06:52.180 --> 06:54.670 As a conclusion in this laboratory lesson. 06:54.670 --> 07:01.480 I want to point out the number of steps that we had to perform and also the number of terminals that 07:01.480 --> 07:06.160 we had to open in order to visualize and move our robot in RVs. 07:06.670 --> 07:13.300 In the next lessons, we will see how to simplify all of these operations with the use of a single command. 07:13.330 --> 07:16.690 Thanks to the launch files that are available in Ros two.