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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.

Epistemic Logic

COMP304 Lectures

The Meanings of $\square$ Consider the epistemic meaning of $\square$: I know that $\phi$ is true. and also the following model: stateDiagram-v2 direction LR w1 --> w2:a w2 --> w1 w2:w2<br>p From this graph we have: $M,w_1\vDash \square_ap$ $M,w_1\nvDash p$ This is bad as agent $a$ knows something that is...

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Scan Model & Likelihood Fields

COMP329 Lectures

Refer to the slides, from 81-94 for this lecture as there are a lot of diagrams. Consider we have a map with objects in it. We can make a likelihood field by applying a Gaussian distribution to the edge of each object in the map. Modelling a Robot with 6...

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Formula Games

COMP304 Lectures

Formula games are formal games between two players: The “game board” is the formula. The Yes player tries to show that the formula is true. The No player tries to show that the formula is false. There is always a winning strategy for one of the players. Formula Games for...

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Morphological Operations

ELEC319 Lectures

Morphology is concerned with the shape of structures. Morphological Erosion 1 The final image is a subset ($\subseteq$) of the original image. Allows objects to shrink and separates objects & regions. It is a pixel-by-pixel operation, sliding the structuring element (SE) at every pixel: If the origin of the SE...

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Sensor Beam Model

COMP329 Lectures

The aim of the sensor model is to determine: \[P(z\mid x)\] what is the probability of a measurement $z$, given that the robot is in state $x$. Beam-Based Sensor Model Consider each beam from the robot’s sensors independently. A scan $z$ is made up of $K$ measurements: \[z=\{z_1, \ldots,z_K\}\] Individual...

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Sample Odometry Motion Model

COMP329 Lectures

Rejection Sampling If we have a function $f$ we can sample random values from this function using the following method: Sample $x$ from a uniform distribution $[-b,b]$. Sample $y$ from $[0,\max f]$ If $f(x)>y$ then keep the sample. Otherwise reject. Sampling vs Odometry Sampling Determines a predicted new pose based...

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Modal Logic - The Proof System $\mathbf K$

COMP304 Lectures

The proof system $\mathbf K$ has the following axioms: $T$ - All the (substitution instances of) validities of propositional logic. $\mathbf K$ - $\square(\phi\implies\psi)\implies(\square\phi\implies\square\psi)$. and the following two rules: MP - If you have derived $\phi$ as well as $\phi\implies\psi$, then derive $\psi$. Necc - If you have derived $\phi$,...

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Sensors & Perception

COMP329 Lectures

Exteroceptive Sensors This is a class of sensors that measure information about a robot’s external environment. They are characterised by a number of different attributes: Field of View & Range Every sensor has a region of space that it can cover: The width of that region is the field of...

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Shapes & Connectivity

ELEC319 Lectures

Pixels, Neighbours & Connectivity $N_4$ Connectivity Each pixel has 4 pixels directly around it. $N_8$ Connectivity This includes diagonally adjacent pixels, so all pixels surrounding a pixel. Structuring Element This is a mask that can be used to define pixel neighbours: It is a small matrix of odd index. 1s...

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