WEBVTT 00:00.400 --> 00:07.070 The Rose to Control library is amazing, as you will see in your career as a robotic software developer. 00:07.090 --> 00:13.900 Almost every robot you will work with will use this library in some way as it solves a fundamental problem 00:13.900 --> 00:18.250 in robotics and does so in a modular and flexible manner. 00:19.150 --> 00:26.080 This library also allows us to activate our simple manipulator robot with only three degrees of freedom, 00:26.230 --> 00:34.240 but it is also used to actuate and coordinate the movement of the wheels of mobile robots and to obtain 00:34.240 --> 00:38.410 feedback to calculate their odometry and so to localize the robots. 00:38.590 --> 00:45.640 And in general it can be used for any other type of robot, regardless of its complexity or the number 00:45.640 --> 00:51.520 of joints that it has and the type of sensors and also independently of the control logic. 00:52.460 --> 00:59.060 This is possible thanks to the configurability and flexibility offered by this library, which can be 00:59.060 --> 01:05.600 configured in many different ways to meet the requirement and the needs of each robot, no matter how 01:05.600 --> 01:07.340 different and unique it is. 01:07.940 --> 01:13.190 In the previous section of the course, we learned how to interact with the parameters of a Ros two 01:13.190 --> 01:18.980 node and how to assign a value to each parameter through the command line interface. 01:18.980 --> 01:22.940 So through the Ubuntu terminal and through the launch files. 01:23.750 --> 01:30.560 However, when I notice so many configurable parameters, we need an easier and more user friendly way 01:30.560 --> 01:36.620 to set all those parameters and also to have an overview of of which values we are setting for each 01:36.620 --> 01:37.400 parameter. 01:38.300 --> 01:41.500 This is where Yaml configuration file comes in. 01:41.510 --> 01:48.860 In Rust two, they allow us to define all the configuration parameters of a node or an application in 01:48.860 --> 01:55.100 a comprehensible, simple and quick format and set all those parameters in one go. 01:55.100 --> 02:00.500 So with a single command so that they are available to a node at runtime. 02:01.740 --> 02:10.590 With the Yaml format variables, object of a class vectors and so on can be represented in a human readable 02:10.590 --> 02:11.160 way. 02:11.550 --> 02:18.450 This allows the values of each parameters to be easily modified and also provides a quick and complete 02:18.450 --> 02:22.410 overview of the configuration parameter that each node is using. 02:23.590 --> 02:28.480 These configuration files for a node starts with the name of the node itself. 02:28.480 --> 02:31.210 That in this case is the controller manager. 02:31.480 --> 02:37.320 Then the Ross parameter tag is used to indicate that we intend to configure this node. 02:37.330 --> 02:41.100 So to set the Ros two parameters of this node. 02:41.110 --> 02:48.400 And then there are the actual parameters of the node, which consists of a name as declared by the node, 02:48.400 --> 02:52.420 and then the value that we want to assign to configure this parameter.