Rico's Nerd Cluster

「离开世界之前 一切都是过程」

Linux - SSH and X Window System

X Window System, SSH, Static IP

SSH Generate an SSH Key: ssh-keygen -t rsa -b 4096. This will create ~/.ssh/id_rsa and optionally sets a passphrase Copy ssh onto a remote machine: ssh-copy-id username@rem...

Posted by Rico's Nerd Cluster on January 5, 2018

Electronics - General Science Facts

Adiabatic Cooling

Adiabatic Cooling In an adiabatic process, the system does not gain or lose heat (Q=0Q=0), meaning that all changes in internal energy come from work done by or on the gas. For an ideal gas, the i...

Posted by Rico's Nerd Cluster on July 1, 2017

Literature - The Wealthy Barber Notes

Financial Literacy

Roy’s Story “We all felt bad about Roy having to put off his dream of becoming a lawyer, but deep down we knew that he was doing the right thing. You got to be there when your family needs you,...

Posted by Rico's Nerd Cluster on June 5, 2017

Electronics - General Electronics Notes

Encoders, Motors, Testing

Electronics EEPROM EEPROM (Electrically Erasable Programmable Read-Only Memory) is a type of non-volatile memory used in microcontrollers to store small amounts of data that must be preserved whe...

Posted by Rico's Nerd Cluster on June 3, 2017

Electronics - Embedded Systems Notes

HAL

HAL vs SAL Hardware Abstraction Layer (HAL) is software that abstracts hardware-specific details from the application or higher-level software. It provides a unified API for accessing hardware fun...

Posted by Rico's Nerd Cluster on June 1, 2017

Electronics - Communication Protocols

Encoding / Decoding, Error Checking (CRC)

Error Checking CRC GF(2) Math GF(2) is pronounced as “Galois Field 2”. Often used in cryptography, it’s a binary field that contains only 0 and 1 for error correction. Some properties of GF(2):...

Posted by Rico's Nerd Cluster on June 1, 2017

Electronics - EMF and Eddy Current

Electromotive Force (EMF，电动势) In short, EMF is: 1 changing magnetic field -> induced voltage It’s characterized by the Faraday’s law: \[\begin{gather*} \begin{aligned} & \epsilon = -N \...

Posted by Rico's Nerd Cluster on June 1, 2017

Math - Linear Fitting

Plane Fitting, Line Fitting

Given a group of points x_i = [x, y, z], how do we find a plane and a line that best fit them? Plane Fitting Points on a plane satisfy: \[\begin{gather*} \begin{aligned} & n^Tx + d = 0 \end{...

Posted by Rico's Nerd Cluster on February 25, 2017

Math - SO(3) Perturbations

Left Perturbation, Right Perturbation, BCH Formula

Left and Right Perturbations Imagine we have a world frame, a car frame, and a pedestrian. Now the car has rotated from the car1 pose to the car2 pose. We assume the pedestrain has not moved: In ...

Posted by Rico's Nerd Cluster on February 22, 2017

Math - Lie Group

Group Definition, Lie Group and Lie Algebras, Skew Matrices, Manifold, SO(3) Derivatives

Group Definition Group (Group) is an algebraic structure consisting of a set and an operation. Denote the set as A, and the operation as ⋅. Then, the group can be written as G=(A,⋅). Closure (...

Posted by Rico's Nerd Cluster on February 22, 2017

FEATURED TAGS
Math Deep Learning C++ Robotics ROS2 Python Linux Computer Vision RGBD Slam Docker ROS SLAM Electronics Hands-on Build Systems CUDA Hands-On ROS1 Web Devel
ABOUT ME

要做一个有 swag 的机器人工程师
Robotics @ Northwestern University

FRIENDS