-
Notifications
You must be signed in to change notification settings - Fork 13
Activity tutorial #205
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
base: trunk
Are you sure you want to change the base?
Activity tutorial #205
Changes from all commits
88bfea9
63dd200
260dbe9
78bf1b7
8170bae
2c0f581
070c3a0
a08538f
e9dcb9d
9825b72
1223fad
848e91c
096f1eb
8bf8159
bc1ed17
f6f6d4a
5f96c75
bf40549
ffeaf3c
f45f002
d6696d2
7be23f0
d04f43d
464cf7c
ac423c6
c0f5df3
6b241e8
28d22e5
ec009df
e2c3ad2
03edd29
File filter
Filter by extension
Conversations
Jump to
Diff view
Diff view
There are no files selected for viewing
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,63 @@ | ||
| { | ||
|
kmjens marked this conversation as resolved.
|
||
| "cells": [ | ||
| { | ||
| "cell_type": "markdown", | ||
| "id": "0", | ||
| "metadata": {}, | ||
| "source": [ | ||
| "# Modelling Active Particles in MD\n", | ||
| "\n", | ||
| "This tutorial explains how to model **active, self-propelled particles** in MD simulations.\n", | ||
| "\n", | ||
| "**Prerequisites:**\n", | ||
| "\n", | ||
| "- This tutorial assumes you have some familiarity with the Python programming language.\n", | ||
| "- This tutorials assume basic understanding of the fundamentals of HOOMD-Blue.\n", | ||
| "- This tutorial uses an example with rod-shaped self-propelled particles which are made with Rigid Bodies in MD. Please refer to the [Modelling Rigid Bodies](../06-Modelling-Rigid-Bodies/00-index.ipynb) tutorial for more details as to how this is done.\n", | ||
| "- [Section 3](03-Motility-Induced-Phase-Separation-In-2D.ipynb) of this tutorial compresses the simualtion box as an example way to induce **Motility Induce Phase Separation (MIPS)**. Please refer to the [Introducing HOOMD-blue](../00-Introducing-HOOMD-blue/05-Compressing-the-System.ipynb) tutorial for more details as to how this is done." | ||
| ] | ||
| }, | ||
| { | ||
| "cell_type": "markdown", | ||
| "id": "1", | ||
| "metadata": {}, | ||
| "source": [ | ||
| "## Outline\n", | ||
| "\n", | ||
| "1. [Introduction to Active Particles](01-Introduction-to-Active-Particles.ipynb)\n", | ||
| "2. [Modelling Active Brownian Particles (ABP Model)](02-Active-Brownian-Particles.ipynb)\n", | ||
| "3. [Motility Induced Phase Separation (MIPS) in 2D Systems](03-Motility-Induced-Phase-Separation-In-2D.ipynb)\n", | ||
| "4. [Modelling Active Rigid Bodies with Active Applied Torques](04-Active-Torque-On-Rigid-Bodies.ipynb)" | ||
| ] | ||
| }, | ||
| { | ||
| "cell_type": "markdown", | ||
| "id": "2", | ||
| "metadata": {}, | ||
| "source": [ | ||
| "This tutorial is written with [jupyter](https://jupyter.org/). You can download the source from the [hoomd-examples](https://github.com/glotzerlab/hoomd-examples) repository." | ||
| ] | ||
| } | ||
| ], | ||
| "metadata": { | ||
| "kernelspec": { | ||
| "display_name": "Python 3 (ipykernel)", | ||
| "language": "python", | ||
| "name": "python3" | ||
| }, | ||
| "language_info": { | ||
| "codemirror_mode": { | ||
| "name": "ipython", | ||
| "version": 3 | ||
| }, | ||
| "file_extension": ".py", | ||
| "mimetype": "text/x-python", | ||
| "name": "python", | ||
| "nbconvert_exporter": "python", | ||
| "pygments_lexer": "ipython3", | ||
| "version": "3.13.7" | ||
| } | ||
| }, | ||
| "nbformat": 4, | ||
| "nbformat_minor": 5 | ||
| } | ||
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,83 @@ | ||
| { | ||
|
Contributor
There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more. "Active particles are particles that can consume stored energy or energy from the environment and convert it into directed motion. There are many different types of active particles with different mechanisms for this realized self-propulsion. For example, a polystyrene bead coated with platinum on one side (i.e. an example of a simple Janus particle, a particle with 2 of more regions of distinct physical properties) will be propelled forward if submerged in a solution containing hydrogen peroxide. This occurs because the platinum catalyzes a chemical reaction that decomposes the hydrogen peroxide into oxygen gas and water. This localized reaction propels the particle forward. In this example, thermal and chemical energy is being consumed to generate the kinetic motion of the (now active) Janus particle." Reply via ReviewNB
Contributor
There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more.
Reply via ReviewNB
Contributor
Author
There was a problem hiding this comment. Choose a reason for hiding this commentThe reason will be displayed to describe this comment to others. Learn more.
In HOOMD-blue, the propulsion velocity is controlled by applying an active force to particles in the system. The relationship between these quantities is $v_{0} = F_{active} / \gamma$ where $\gamma$ is the translational drag coefficient (often = 1 in overdamped Brownian dynamics).
|
||
| "cells": [ | ||
| { | ||
| "cell_type": "markdown", | ||
| "id": "0", | ||
| "metadata": {}, | ||
| "source": [ | ||
| "# Introduction to Active Particle Systems\n", | ||
| "\n", | ||
| "## Overview\n", | ||
| "\n", | ||
| "### Questions\n", | ||
| "\n", | ||
| "* How can we model particles with self-induced **active forces**?\n", | ||
| "* What types of information can we learn from **non-equilibrium** systems?\n", | ||
| "\n", | ||
| "### Objectives\n", | ||
| "\n", | ||
| "* Introduce the **Active Brownian Particle (ABP) model** \n", | ||
| "* Define **Motility-Induced Phase Separation (MIPS)**. \n", | ||
| "* Discuss the mechanics of **rigid bodies responding to active forces** using torque as an example." | ||
| ] | ||
| }, | ||
| { | ||
| "cell_type": "markdown", | ||
| "id": "1", | ||
| "metadata": {}, | ||
| "source": [ | ||
| "## Introduction to Active Particles\n", | ||
| "\n", | ||
| "**Active particles** are particles that can consume stored energy or energy from the environment and convert it into directed motion. There are many different types of active particles with different mechanisms for this realized self-propulsion. For example, a polystyrene bead coated with platinum on one side (i.e. an example of a simple **Janus particle**, a particle with 2 of more regions of distinct physical properties) will be propelled forward if submerged in a solution containing hydrogen peroxide. This occurs because the platinum catalyzes a chemical reaction that decomposes the hydrogen peroxide into oxygen gas and water. This localized reaction propels the particle forward. In this example, thermal and chemical energy is being consumed to generate the kinetic motion of the (now active) Janus particle.\n", | ||
| "\n", | ||
| "In the previous HOOMD-blue tutorials, most of the systems have been models with which one could investigate **equilibrium properties** where the steady state is independent of kinetic parameters. When studying **active matter**, however, we are no longer considering equilibrium processes, and we shift our attention to **non-equilibrium dynamics**. Regardless, we can set up the initial state of the simulation in a very similar manner to previous methods we have used in [earlier hoomd MD simulation tutorials](../01-Introducing-Molecular-Dynamics/00-index.ipynb). " | ||
| ] | ||
| }, | ||
| { | ||
| "cell_type": "markdown", | ||
| "id": "1bf55e0d-a51e-4782-a6bb-1145a4de5391", | ||
| "metadata": {}, | ||
| "source": [ | ||
| "### Active Particles and their Phenomena:\n", | ||
| "There are a few categories of active particles. Here we introduce the commonly discussed **Active Brownian Particle (ABP)**. Cates and Tailleur have a helpful figure distinguishing this active particle type from others their [2015 Annual Review Condensed Matter Physics Paper](https://www.annualreviews.org/content/journals/10.1146/annurev-conmatphys-031214-014710). The left image shows an example cartoon trajectory of an alternate type of active particle called a Run-and-Tumble particle (Fig. a), and the right shows an example cartoon trajectory for an ABP (Fig. b). This tutorial focuses on modeling **dry active matter** with ABPs. \n" | ||
| ] | ||
| }, | ||
| { | ||
| "cell_type": "code", | ||
| "execution_count": null, | ||
| "id": "0fe709c5-c4da-47a7-8258-800d548ca347", | ||
| "metadata": {}, | ||
| "outputs": [], | ||
| "source": [] | ||
| }, | ||
| { | ||
| "cell_type": "code", | ||
| "execution_count": null, | ||
| "id": "c76f129c-4027-4219-8030-781b733ffe55", | ||
| "metadata": {}, | ||
| "outputs": [], | ||
| "source": [] | ||
| } | ||
| ], | ||
| "metadata": { | ||
| "kernelspec": { | ||
| "display_name": "Python 3 (ipykernel)", | ||
| "language": "python", | ||
| "name": "python3" | ||
| }, | ||
| "language_info": { | ||
| "codemirror_mode": { | ||
| "name": "ipython", | ||
| "version": 3 | ||
| }, | ||
| "file_extension": ".py", | ||
| "mimetype": "text/x-python", | ||
| "name": "python", | ||
| "nbconvert_exporter": "python", | ||
| "pygments_lexer": "ipython3", | ||
| "version": "3.13.7" | ||
| } | ||
| }, | ||
| "nbformat": 4, | ||
| "nbformat_minor": 5 | ||
| } | ||
Uh oh!
There was an error while loading. Please reload this page.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Please keep the style of the previous tutorials. That means get rid of the introduction (especially as it is nearly identical to the one on the next page), and simply say something like: "This tutorial explains how to model active, self-propelled particles in MD simulations."
And then you say
"This tutorial assumes you are familiar with the concepts introduced in Introducing HOOMD-blue, Introducing Molecular Dynamics and Modelling Rigid Bodies."
Where are you confining particles?
Reply via ReviewNB
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
changes made in newest commit about to be pushed. Wording on confinement corrected to reference Intro HOOMD tutorial where box compression (not confinement via walls) is introduced.