Emergency Braking of Ego Vehicle in CARLA Simulator Using Simulink and CARLA ROS Bridge

This example uses:

This example shows how to set up, connect to, and control an ego vehicle in the CARLA simulator using ROS Toolbox™.

Overview

You control the CARLA ego vehicle by sending steering, braking, and throttle control signals to a vehicle controls publisher using Simulink® software. The model reads point cloud data from the front camera, odometer, and lidar sensors of the ego vehicle. The point cloud processor removes ground reflection and calculates the average distance of the objects in front of the ego vehicle. The model sends the calculated distance to the emergency braking unit which issues a braking command if the distance drops below 10 meters.

Setup

Install the latest CARLA simulator on your host machine. This example uses the binary installation of version 0.9.13 of the CARLA Simulator.

Download and install the ROS Virtual Machine. This virtual machine is based on the Ubuntu® Linux® operating system and is pre-configured to support the examples in ROS Toolbox™.

To set up and launch the NVIDIA Isaac Sim® from MATLAB®, see Set Up and Connect to CARLA Simulator.

Here is the diagram depicts the setup of this example.

Control Ego Vehicle in CARLA Using Simulink

Connect Simulink to the ROS master running in the VM Ware.

rosinit('http://172.18.226.233:11311')

Initializing global node /matlab_global_node_37271 with NodeURI http://172.18.226.60:60619/ and MasterURI http://172.18.226.233:11311.

Ensure that you can access ROS topics related to the CARLA simulator by running the following introspection command.

rostopic list

/carla/ego_vehicle/collision                      
/carla/ego_vehicle/control/set_transform          
/carla/ego_vehicle/enable_autopilot               
/carla/ego_vehicle/gnss                           
/carla/ego_vehicle/lane_invasion                  
/carla/ego_vehicle/odometry                       
/carla/ego_vehicle/rgb_view/image                 
/carla/ego_vehicle/vehicle_control_cmd_manual     
/carla/ego_vehicle/vehicle_control_manual_override
/carla/ego_vehicle/vehicle_info                   
/carla/ego_vehicle/vehicle_status                 
/carla/status                                     
/clock                                            
/initialpose                                      
/rosout                                           
/rosout_agg                                       
/tf

Open the Simulink model.

open_system('EmergencybrakingofCarlaEgoVehicle');

The model shows the point cloud data from the lidar sensor that the vehicle uses to measure the distance to the obstacle. When the distance is below 10 meters, the emergency braking system sends a braking command to the vehicle.

Run the Simulink model. The ego vehicle automatically stops 10 meters ahead of the vehicle in front of it at the gas station. The CARLA ROS manual control terminal shows the stationary vehicle with the brake applied.

Shut down the ROS network.

rosshutdown

Shutting down global node /matlab_global_node_37271 with NodeURI http://172.18.226.60:60619/ and MasterURI http://172.18.226.233:11311.