Software Component : Steering Column Demo

Introduction

Demonstrate Sterring Column control using RTI Connext DDS.

Dependencies

• RTI Connext Professional 7.3 LTS (SDK) for DDS

• connextauto-bus for common data architecture

  • (if not done already) Follow the Getting Started instructions in connextauto-bus repo

  • At this point, the directory structure should look like this:

    /path/to/connextauto/
        ├── connextauto-bus
    

  • $DATABUSHOME refers to /path/to/connextauto/connextauto-bus

• Python for Visualization (OPTIONAL)

  • Install packages

    • Linux (Ubuntu)

      apt install python3-pip python3-pil python3-pil.imagetk
      

    • macOS

      brew install [email protected] pillow [email protected]
      

  • Create and activate venv

     python3.12 -m venv .venv
     . .venv/bin/activate
    

  • Install python libraries in the venv

     pip install pillow
    
     # rti.connext (see RTI Connext Getting Started)
     pip install rti.connext.activated -f $NDDSHOME/resource/python_api
    

Getting Started

• Clone (or fork and clone) this repo into the connextauto/ directory (see Dependencies)

  cd /path/to/connextauto/
  
  git clone <git_url_to_this_repository>
  

  The directory structure should look like this:

  /path/to/connextauto/
        ├── connextauto-bus
        ├── connextauto-swc-steering
  

• Change to the software component (swc) directory:

  cd connextauto-swc-steering/
  

• Build for the target architecture

  make -f makefile_<arch>
  

  e.g.:

  <arch> = x64Linux4gcc7.3.0

  make -f makefile_x64Linux4gcc7.3.0
  

  <arch> = armv8Linux4gcc7.3.0

    make -f makefile_armv8Linux4gcc7.3.0
  

Run the applications

The platform independent makefile provides a launcher to run the apps. The generic pattern for launching the apps is as follows.

  make <arch>/<app>

e.g. <arch> = x64Linux4gcc7.3.0

  make x64Linux4gcc7.3.0/display
  make x64Linux4gcc7.3.0/controller
  make x64Linux4gcc7.3.0/actuator

<arch> = armv8Linux4gcc7.3.0

  make armv8Linux4gcc7.3.0/display
  make armv8Linux4gcc7.3.0/controller
  make armv8Linux4gcc7.3.0/actuator

<arch> = Python

  make py/display
  make py/controller

You can pass enviornment variables to make as follows. The example below sets the environment variable STEERING_CONTROLLER_STRENGTH to 20

  make STEERING_CONTROLLER_STRENGTH=20 x64Linux4gcc7.3.0/controller

  make STEERING_CONTROLLER_STRENGTH=20 armv8Linux4gcc7.3.0/controller

  make STEERING_CONTROLLER_STRENGTH=20 py/controller

Running on a remote target (eg Raspberry Pi)

• On Local Terminal: Package apps and config files

    make <arch>/package
  

  e.g.

      make armv8Linux4gcc7.3.0/package
      make x64Linux4gcc7.3.0/package
  

  This step creates a package ./steering_<arch>.tgz

• Transfer the package to the remote host, e.g.:

  scp steering_<arch>.tgz user@server:/remote/path/
  

• On Remote Terminal: Unpack the apps and config files

  cd /remote/path
  tar zxvf steering_<arch>.tgz
  cd connextauto-swc-steering
  

• On Remote Terminal, run apps as before for the target architecture

Data Architecture

The demo comprises of three applications exchanging data over the RTI Connext Databus, using DDS. They use the datatypes defined in the files below.

• $DATABUSHOME/res/types/data/actuation/Steering_t.idl

The Quality of Service (QoS) profiles are defined in the files below.

• $DATABUSHOME/res/qos/services/steering/

The data interfaces are defined in the files below.

• $DATABUSHOME/if/steering/

You can browse the data architecture using RTI System Designer:

• Launch RTI System Designer
• Open the $DATABUSHOME/connextauto.rtisdproj project in the RTI System Designer

Component Applications

The component applications are decribed below.

• SteeringColumn, a.k.a. the actuator, reads steering commands and writes steering status
• SteeringController writes steering commands
• SteeringDisplay takes and displays steering status

The SteeringColumn is implemented in C++. The SteeringController and SteeringDisplay components have two implementaion variants: one in C++ with a textual user interface, and another in Python with a GUI.

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