tf dude

I have a dude for everything. There is the 300 inch-TV dude, there is the ticket dude, there is dude for a suit.

-Barney Stinson, more or less

But who you gonna call (:ghost:) when asking for the transform between your robot's links or the world frame? The answer is easy, you call the tf dude.

Overview

tf_dude, as part of the dude framework, centralizes dependent transformations in a single forest of transformation trees. The main purpose is to provide a simple yet powerful interface for accessing transformations from any process in the processing network. Furthermore, it includes uncertainty estimations based on Lie Algebra to take into account tolerances, gravity impact or other sources of sensor noise.

Roadmap

• tf library
  • core functionality
  • generic IPC
  • Client API (Functions for CRUD, Handles for Frames & Paths)
  • Lie Algebra integration (currently no uncertainty support)
  • robust exception handling
  • Smart Caching of handle data
  • Temporal caching of frame data
  • event-based updates of client data
  • Reduction of network-load
  • local-cluster high-speed integration
• plugins
  • links_and_nodes implementation
  • ROS implementation
• tf_dude
  • simple CLI server app
  • init_tree integration
  • visualization

How to use

Find out in the documentation.

Development

Toolchain File

For local development, you need to pass the toolchain file directly to CMake. For CLion this can be automated using by adding the following CMake option in File->Settings->Build...->CMake

-DCMAKE_TOOLCHAIN_FILE=$CMakeProjectDir$/build/conan_paths.cmake

Selecting the right plugin

The tf_dude library is independent on any IPC framework. However, if you are developing, you might want to test your code somehow, for this you need to active the right plugin for your environment. By default, tf_dude builds for ROS, but if you want another plugin, you have to activate the build:

For LN add the following to your build seetings (also deactivating ROS/ROS2 for less build stuff)

-DBUILD_MODULE_TF_PLUGINS_LN=ON
-DBUILD_MODULE_TF_PLUGINS_ROS=OFF
-DBUILD_MODULE_TF_PLUGINS_ROS2=OFF

The last thing missing is setting the default plugin to load

-DDEFAULT_PLUGIN=ln

Creating a dev environment using conan

Depending on the IPC you are using, you can create your environment using (in the root of the repository)

conan install conanfile.tf_dude.<IPC>.py -if <BUILD_FOLDER> -g virtualenv [-u]

for example for ROS it is

conan install conanfile.tf_dude.ros.py -if <BUILD_FOLRDER> -g virtualenv [-u]

some IPC implementation split the message definition and the compilation into two packages, e.g. LN, here you first have to build the definitions

cissy create conanfile.ln_msg_defs.py -rv None

Note the -rv None for creating a revision with the name None