Rico's Nerd Cluster

「离开世界之前 一切都是过程」

C++ - Datastructures

Priority Queue

std::priority_queue (Priority Queue, or Max-Heap) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 #include <iostream> #include <...

Point Cloud Library

Point Infrastructure Point Cloud Members PointCloud Type includes points: point vector PointTypes PointType include: pcl::PointXYZ pcl::PointXYZI pcl::PointXYZRGB pcl::PointXYZRGB...

Robotics - General ESKF Hands-on Test Notes

Primers Did you turn on the message debugging flag, or are you compiling with PRINT_DEBUG_MSGS? Are you sure you are launching the right test? IMU tools Velocity drift observed. Here, I’m ...

Robotics - [IMU Pre-integration Model 4] IMU Pre-integration Optimization Implementation

IMU Pre-Integration, GNSS, UTM

Using Pre-Integration Terms as Edges in Graph Optimization Formulating a graph optimization problem using pre-integration (as edges) and states as nodes is quite flexible. Recall that from here th...

Robotics - [IMU Pre-integration Model 3] Noise Model

Jacobian Derivation

Pre-integration Model In Graph Optimization using IMU pre-integration, $b_g$ and $b_a$ are factors under optimization. We have derived the Jacobians of pre-integrated intermediate values w.r.t the...

Robotics - [IMU Pre-integration Model 2] How To Update Pre-integration With Changing IMU Biases

Jacobian Derivation

Update Pre-integration When Updating Biases Pre-integration parts are functions are functions w.r.t gyro and acceleration biases: $b_{g,i}, b_{a,i}$. In graph optimization, we would usually need t...

Robotics - [IMU Pre-integration Model 1] Definitions Of Pre-Integration Options

Pre-Integration Model Definitions

Motivation In previous posts, we have seen the ESKF framework, where IMU data is fused with observations (GNSS, encoders) following this incremenetal order: 1 ESKF Prediction with IMU | ESKF Pred...

Robotics - [ESKF Series 5] Why Using Error-State Kalman Filter (ESKF) For IMU

ESKF, GINS

ESKF Handles Rotations on SO(3) Better Key issue: Rotations lie on the special orthogonal group SO(3), which is a nonlinear manifold (not a simple vector space like position). A standard EKF typic...

Robotics - [ESKF Series 4] Full Error-State Kalman Filter (ESKF) in GNSS-Inertial Navigation System (GINS)

ESKF, GINS

If you haven’t checked out a motivational 2D robot example of ESKF, please check here. In this post, $\oplus$ is the “generic add”, which “adds” on a manifold. ESKF (On Manifold) in GINS (GPS-Int...

Robotics - [ESKF Series 3] Motivational Example Of Error-State Kalman Filter (ESKF)

ESKF

Motivating Example We use the same example as the one in the EKF post: imagine our world has two cones with known locations: c1, c2, and a diff drive with wheel encoders and a cone detector. T...