AV1Tenth Simulator

This simulator uses the bicycle model to simulate the motion of the av1tenth vehicle.

Run the command below to start the simulator with RViz (after building and sourcing)

ros2 launch av1tenth_sim rviz_simulator.launch.py

Use with Teleop

To use the class teleop project with the simulator, include the remappings options in the launch file for the teleop node.

teleop = Node(
    package='class_teleop',
    executable='teleop',
    output='screen',
    remappings=[
        ('/vehicle_command_ackermann', '/simulator/vehicle_command_ackermann')
    ]
)

I/O

All MessageTypes used are standard ROS messages and their specifics can be found by a google search.

Inputs

Format	Message Type	Name
Subscription	AckermannDriveStamped	/simulator/vehicle_command_ackermann

Outputs

Format	Message Type	Name
Publisher	PoseStamped	/simulator/utm_pose
TransformBroadcaster	TransformStamped	/tf2

Launch File Example

If you want to start this simulator from a ROS 2 launch file, then use the sample code below.

Note: If you specify 'utm_local' for the output_coordinates, you must provide a static transform publisher between 'utm' and 'utm_local'.

simulator = Node(
    package = 'av1tenth_sim',
    executable = 'simulator',
    output = 'screen',
    parameters = [
        {
            'initial_position': [29.967755, -85.472341], # Lattitude, Longitude
            'initial_heading': 10.0, # Degrees from east
            'veh_sim.sim_time_step': 0.02, # seconds
            'veh_sim.output_coordinates': 'utm', # either 'utm' or 'utm_local'
            'veh_sim.track': 0.1937, # meters
            'veh_sim.kingpin_width': 0.1524, # meters
            'veh_sim.wheelbase': 0.3143, # meters
            'veh_sim.steering_motion_delay': 2.0, # steering rate (rad/s)
            'veh_sim.steering_signal_delay': 0.0, # seconds
            'veh_sim.speed_delay': 2.5, # acceleration (m/s^2)
            'veh_sim.position_feedback_noise': 0.002,  # standard deviation (meters)
            'veh_sim.velocity_feedback_noise': 0.04,  # standard deviation (m/s)
        }
    ]
)

Here is an example of specifying the 'utm' to 'utm_local' transform in a launch file.

import utm # Place this at the top
reference_point = [29.967765, -85.472428]
easting, northing, _, _ = utm.from_latlon(latitude=reference_point[0], longitude=reference_point[1])
tf = Node(
    package='tf2_ros',
    executable='static_transform_publisher',
    name='utm_to_utm_local',
    arguments = ['--x', str(easting), '--y', str(northing), '--frame-id', 'utm', '--child-frame-id', 'utm_local']
)
ld.add_action(tf)

Params File Example

If you want to load the parameters using a params.yaml file you can use the sample below.

Note: If you specify 'utm_local' for the output_coordinates, you must provide a static transform publisher between 'utm' and 'utm_local'.

/**: # Matches what ever calls it. Only for single node param files
  ros__parameters:
    initial_position: [29.967765, -85.472428]  # Lattitude, Longitude
    initial_heading: 10.0  # Degrees from east
    veh_sim:
      sim_time_step: 0.02 # seconds
      output_coordinates: 'utm' # either 'utm' or 'utm_local'
      track: 0.1937 # meters
      kingpin_width: 0.1524 # meters
      wheelbase: 0.3143 # meters
      steering_motion_delay: 0.698132 # steering rate (rad/s)
      steering_signal_delay: 0.0 # seconds
      speed_delay: 0.5 # acceleration (m/s^2)
      position_feedback_noise: 0.002  # standard deviation (meters)
      velocity_feedback_noise: 0.0  # standard deviation (m/s)