Mobile Robotics
Content
This part of the course covers mobile robotics. We will cover the topics
- Lecture 9: Locomotion, Sensing and Perception
- Lecture 10: Localisation
- Lecture 11: Mapping and SLAM
- Lecture 12: Navigation
This part of the course spans a much larger area of robotics than the previous lectures and the amount of material to read if you wanted to read it all is therefore quite staggering. The aim for this part of the course is to get a basic understanding for the concepts and methods rather than going into details.
First of all there are several ways in which we can implement a locomotion system. In the first lecture we will give an overview of different means of locomotion. When we start moving, the requirements on sensing becomes even larger. Even if the world is static, which we often assume, what the robot is exposed to will change because the robot changes position. We need sensing to sense the world around us so that we know how to interact with it, avoid running into it, etc. In the first lecture we will also look at different sensing modalities.
When we start moving in the world we introduce uncertainty not only in what the world around us looks like but also where we are in the world. Localisation is one of the enabling technologies, not only in mobile robotics, but also in, for example, location based services. In the second lecture we will look at the problem of localisation and will also discuss estimation in general.
In order to localise the robot we need to have a map of the environment to which we can relate our position. This map can come in many forms. When we use the GPS system the map can be said to consist of the GPS satellites and their known positions. For realise a truly autonomous systems, the system need to be able to build the map on its own. This is trick as we just said that the map is used for the localisation as well and the location is needed to do the mapping. In the fourth lecture we will look at the problem of SLAM, or simultaneous localization and mapping which is the solution to this chicken or egg problem. We will also discuss variations of the SLAM problem such as visual odometry.
In the final problem discuss the navigation problem, which refers to being able to go from A to B. This requires all of the above and also the ability to plan the motion and to execute it while making sure that obstacles are avoided. We will also, if time permits look at some challenges with building a complete system.
Pre-Lecture Quizzes
The purpose of the quizzes before the lecture is to provide an incentive to prepare for the lecture so that you get more out of the lectures. Note that the quiz only tests if you are prepared for the lecture, not if you already know everything required for this part of the course.
Assignment
In the assignment corresponding to this module you will build a map of the environment. This connects what we will talk about in all four lectures on mobile robotics. You will be using data from a laser scanner collected by a robot moving around in an unknown environment. The laser scanner allows the robot to gather information about the environment (sensing). It is using its encoders (sensing) to estimate the position while it is moving (localization). The robot uses the position information and the laser data to build a map of the environment (mapping). In the C-part we also discuss how to process this map to support motion planning and execution of such plans (navigation).