The raw_vehicle_command_converter is a crucial node in vehicle automation systems, responsible for translating desired steering and acceleration inputs into specific vehicle control commands. This process is achieved through a combination of a lookup table and an optional feedback control system.
The core of the converter's functionality lies in its use of a CSV-formatted lookup table. This table encapsulates the relationship between the throttle/brake pedal (depending on your vehicle control interface) and the corresponding vehicle acceleration across various speeds. The converter utilizes this data to accurately translate target accelerations into appropriate throttle/brake values.
Reference data for the lookup table is generated through the following steps:
- Data Collection: On a flat road, a constant value command (e.g., throttle/brake pedal) is applied to accelerate or decelerate the vehicle.
- Recording Data: During this phase, both the IMU acceleration and vehicle velocity data are recorded.
- CSV File Generation: A CSV file is created, detailing the relationship between command values, vehicle speed, and resulting acceleration.
Once the acceleration map is crafted, it should be loaded when the RawVehicleCmdConverter node is launched, with the file path defined in the launch file.
For ease of calibration and adjustments to the lookup table, an auto-calibration tool is available. More information and instructions for this tool can be found here.
| Name | Type | Description |
|---|---|---|
~/input/control_cmd |
autoware_control_msgs::msg::Control | target velocity/acceleration/steering_angle/steering_angle_velocity is necessary to calculate actuation command. |
~/input/steering" |
autoware_vehicle_msgs::msg::SteeringReport | current status of steering used for steering feed back control |
~/input/odometry |
navigation_msgs::Odometry | twist topic in odometry is used. |
| Name | Type | Description |
|---|---|---|
~/output/actuation_cmd |
tier4_vehicle_msgs::msg::ActuationCommandStamped | actuation command for vehicle to apply mechanical input |
{{ json_to_markdown("vehicle/autoware_raw_vehicle_cmd_converter/schema/raw_vehicle_cmd_converter.schema.json") }}
The current feed back implementation is only applied to steering control.