Documentation for obelisk

Table of Contents:

• Getting Started
• Development
  • Overview
  • Getting Started
  • Building and Running the ROS Stack
  • Building and Running C++ Code
  • C++ Code Structure
• Obelisk API
  • Overview
  • Obelisk Nodes
  • Obelisk Messages and Topics
• Using Obelisk - Basic Example
  • Controller Code
  • Estimator Code
  • Spinning all the Nodes
  • Obelisk Configuration File
• Visualization
  • Robot Visualization
  • Implementing a Custom Robot Visualization
• Logging
• Obelisk Terminal Aliases
  • obk-launch
  • State Transitions
  • Convenience Commands
• Frequently Asked Questions
  • Installing
  • C++ Library
  • Python Library
  • General
  • Errors

Overview

obelisk is a shared robot control interface for the robots in the AMBER Lab at Caltech. Welcome!

The goal of obelisk is to provide a lightweight, convenient API built on ROS2 that forms a barebones stack for robotic systems of interest. Some elements of the project that we emphasize:

• Hardware deployment should be identical or as close as possible to simulated deployment. That is, by simply switching a flag, we should be able to visualize and test code in simluation and then immediately run the same code on hardware seamlessly.

• The block diagram for every system follows a standard: a model (either the hardware or sim) exists which we want to control, which sends information back to a state estimator, which sends an observation to the controller, which executes a control action. The focus of the end-user should be on designing elements of the controller or state estimator - once the system model is specified, it should abstractly be able to interface with any compatible controller or estimator. There are also sensor blocks which represent offboard sensing elements (such as external cameras), which provide additional signal to the state estimator.

• In particular, end-user development should be agnostic to our ROS2 code, which only thinly wraps control code and allows different elements of the stack to communicate with each other.

• Unified logging and visualization tools are important for understanding system behavior and debugging. These utilities are provided in obelisk.