This website houses notes from my studies at the University of Liverpool. If you see any errors or issues, please do open an issue on this site's GitHub.
Four Basic Wheel Types Standard Wheel Spherical Wheel - A ball with omnidirectional movement. Castor Wheel - A wheel that can rotate around a castor and it’s own axle. Swedish Wheel - A wheel made of 45 degree rollers. This allows passive motion in the direction of the rollers. Characteristics...
Potential Fields The robot is treated as a point under the influence of an artificial potential field. The filed depends on the targets and goal as well as desired travel directions. The goal attracts it, whilst obstacles repel it. The strength of the field may change with the distance to...
This is the process of using simple rules to create complex behaviours. Steel’s Mars Explorer System Consider that we have a robot that we want to explore a distant planet and collect samples of rock. We know that the locations of the rocks tend to be clustered. We can use...
Truth-Functionality The connectives of propositional logic are truth-functional: This means that the truth of $\phi\wedge\psi$ is fully determined by the truth of $\phi$ and $\psi$. If a proposition is not truth-functional we can describe it like so: \[\phi = \begin{cases} p & \text{That happens to be true}\\ \top & \text{That...
Agents With State graph TB Environment --> see subgraph Agent see --> next next --> state state --> next state --> action end action --> Environment Tasks for Agents We want to tell agents to complete a particular task without telling them how to do it. We can achieve this...
Terminology Field of View Total angle covered by the camera in a single image. Field of Regard Total angle that can be covered by the camera in a series of images. Focal Length (fl) Effective distance between lens and focal plane. Aperture (d) Effective size of the lens. Pixel Individual...
Agent An agent is a computer system that is situated in some environment, and that is capable of autonomous action in that environment in order to meet its delegated objectives. Agents can make their own decisions. Tele-operated systems aren’t agents. Mobile Robotics There are three main questions in mobile robotics:...
Language This is what defines a well formed formula (wff) in a particular logic. We start with a set $\mathcal P$ of atoms, $\mathcal P = p, q, p_1, p_2,\ldots$ These represent basic facts that we don’t analyse further. The atoms determine the level of detail that we consider. Well...
Digital Images Discrete representation of spatial and intensity values in a 2D matrix. Raw images are often: Extremely noisy Contain invisible bands of the EM spectrum. Contain too much information (that needs to be cropped out) Image Sensing & Optics Images are a signal so it is collected using a...
Symmetric Key Cryptography This topic has been covered before in: COMP211 - Symmetric Key Cryptography One-Time Pad This is one of the most secure ciphers known. For this encryption scheme Alice and Bob share a random bit string $K$ that is as long as any message that are going to...