WEBVTT 00:00.230 --> 00:05.420 As we have seen in the previous lesson, Ros stands for Robot Operating system. 00:05.600 --> 00:12.800 Anyway, don't let the name mislead you since to be honest, Ros isn't a proper operating system, but 00:12.800 --> 00:19.160 you can consider it more as a software that you can install on your PC and that simulates some functionalities 00:19.160 --> 00:23.330 of a real operating system, but for robotics applications. 00:24.130 --> 00:29.650 There are four main aspects of Ros that make it similar to an operating system. 00:29.980 --> 00:33.070 Among them there is the hardware abstraction. 00:33.780 --> 00:39.270 Let's start understanding the hardware abstraction with an analogy with the operating system running 00:39.270 --> 00:40.020 on your PC. 00:40.650 --> 00:47.940 Whether you are using Windows Linux or Mac OS, this operating system allows you to use the hardware 00:47.940 --> 00:55.170 of your PC independently by the processor that you are using or by the amount of memory that you have. 00:55.380 --> 01:01.790 For sure, the performance will be different if you have a better CPU or much memory available. 01:01.800 --> 01:08.730 But anyway, you can use your computer the same way whether you have an Intel CPU or an AMD. 01:08.730 --> 01:16.050 One to the point that very often you can use also a PC without even actually knowing which CPU it has. 01:16.640 --> 01:23.120 To be honest, all the hardware components are very different from each other and very often they require 01:23.120 --> 01:29.390 a different communication protocol and they also use a different logic in order to directly use the 01:29.390 --> 01:30.380 hardware of your PC. 01:30.680 --> 01:38.120 You will need to know exactly the brand of the device, its version and its communication protocol. 01:38.390 --> 01:45.110 The operating system of your PC is in charge of managing all of these for you and also provides you 01:45.110 --> 01:51.050 only a standard interface to use the hardware independently by its specifications. 01:52.460 --> 01:53.510 The same way. 01:53.510 --> 02:00.350 The operating system also offers a standard interface for the other applications that you use and that 02:00.350 --> 02:01.550 you install on your PC. 02:01.760 --> 02:03.560 To use its resources. 02:03.890 --> 02:10.610 This way, the software developers don't have to worry about the hardware specification of the PC of 02:10.610 --> 02:17.750 the users, and so they can develop a general purpose software that will work on any PC and rely on 02:17.750 --> 02:22.100 the operating system to make it work with the available resources. 02:23.200 --> 02:31.090 Likewise, Ross is in charge of managing the hardware of our robot, providing to the user a standard 02:31.090 --> 02:34.750 interface for the usage of sensors or motors. 02:36.090 --> 02:43.470 It also offers a standard interface for all the software developers of robotics applications that this 02:43.470 --> 02:49.020 way you don't have to worry about the type of motors or which communication protocol are they using, 02:49.020 --> 02:54.990 but they can only focus on the development of new functionalities for the robot and leave the interface 02:54.990 --> 02:56.670 orchestration to Ross.