Implementation:CARLA simulator Carla BlueprintLibrary Find For Sensors

Knowledge Sources	CARLA Simulator CARLA Documentation
Domains	Simulation, Perception
Last Updated	2026-02-15 00:00 GMT

Overview

Concrete tool for locating sensor blueprints by ID and configuring their attributes provided by the CARLA simulator.

Description

BlueprintLibrary.find() retrieves a specific ActorBlueprint by its string identifier from the world's blueprint library. For sensor data collection, this is used to obtain blueprints for camera, LiDAR, radar, GNSS, and IMU sensors. Once retrieved, ActorBlueprint.set_attribute() modifies the sensor's configuration parameters such as image resolution, field of view, number of LiDAR channels, and noise characteristics. All attribute values are passed as strings regardless of their underlying type.

Usage

These methods are used together when setting up a sensor data collection rig. First, find() retrieves the blueprint for the desired sensor type, then set_attribute() is called one or more times to configure its parameters before passing the blueprint to World.spawn_actor().

Code Reference

Source Location

• Repository: CARLA
• File: LibCarla/source/carla/client/BlueprintLibrary.h (L48), PythonAPI/carla/src/Blueprint.cpp (L105-113)
• Lines: L48 (find), L105-113 (set_attribute)

Signature

BlueprintLibrary.find(id: str) -> carla.ActorBlueprint
ActorBlueprint.set_attribute(key: str, value: str) -> None

Import

import carla

I/O Contract

Inputs

Name	Type	Required	Description
id	str	Yes	Hierarchical sensor blueprint identifier (e.g., sensor.camera.rgb, sensor.lidar.ray_cast, sensor.other.radar, sensor.other.gnss, sensor.other.imu).
key	str	Yes	Attribute name to configure (e.g., image_size_x, fov, channels, range).
value	str	Yes	Attribute value as a string. Numeric values are converted internally (e.g., "1920", "90.0", "64").

Outputs

Name	Type	Description
blueprint	carla.ActorBlueprint	The retrieved sensor blueprint, ready for attribute configuration and spawning. find() raises RuntimeError if the ID is not found.
(none)	None	set_attribute() modifies the blueprint in place and returns None.

Usage Examples

Basic Example

import carla

client = carla.Client('localhost', 2000)
client.set_timeout(10.0)
world = client.get_world()
blueprint_library = world.get_blueprint_library()

# Configure an RGB camera sensor
camera_bp = blueprint_library.find('sensor.camera.rgb')
camera_bp.set_attribute('image_size_x', '1920')
camera_bp.set_attribute('image_size_y', '1080')
camera_bp.set_attribute('fov', '90')
camera_bp.set_attribute('sensor_tick', '0.05')  # 20 Hz

Multi-Sensor Suite Configuration

import carla

client = carla.Client('localhost', 2000)
client.set_timeout(10.0)
world = client.get_world()
bp_lib = world.get_blueprint_library()

# --- RGB Camera ---
rgb_bp = bp_lib.find('sensor.camera.rgb')
rgb_bp.set_attribute('image_size_x', '1920')
rgb_bp.set_attribute('image_size_y', '1080')
rgb_bp.set_attribute('fov', '110')

# --- Depth Camera ---
depth_bp = bp_lib.find('sensor.camera.depth')
depth_bp.set_attribute('image_size_x', '1920')
depth_bp.set_attribute('image_size_y', '1080')
depth_bp.set_attribute('fov', '110')

# --- Semantic Segmentation Camera ---
seg_bp = bp_lib.find('sensor.camera.semantic_segmentation')
seg_bp.set_attribute('image_size_x', '1920')
seg_bp.set_attribute('image_size_y', '1080')
seg_bp.set_attribute('fov', '110')

# --- LiDAR ---
lidar_bp = bp_lib.find('sensor.lidar.ray_cast')
lidar_bp.set_attribute('channels', '64')
lidar_bp.set_attribute('range', '100.0')
lidar_bp.set_attribute('points_per_second', '1200000')
lidar_bp.set_attribute('rotation_frequency', '20')
lidar_bp.set_attribute('upper_fov', '15.0')
lidar_bp.set_attribute('lower_fov', '-25.0')

# --- Radar ---
radar_bp = bp_lib.find('sensor.other.radar')
radar_bp.set_attribute('horizontal_fov', '30.0')
radar_bp.set_attribute('vertical_fov', '30.0')
radar_bp.set_attribute('range', '100.0')

# --- GNSS ---
gnss_bp = bp_lib.find('sensor.other.gnss')
gnss_bp.set_attribute('noise_alt_stddev', '0.1')
gnss_bp.set_attribute('noise_lat_stddev', '0.00001')
gnss_bp.set_attribute('noise_lon_stddev', '0.00001')

# --- IMU ---
imu_bp = bp_lib.find('sensor.other.imu')
imu_bp.set_attribute('noise_accel_stddev_x', '0.1')
imu_bp.set_attribute('noise_accel_stddev_y', '0.1')
imu_bp.set_attribute('noise_accel_stddev_z', '0.1')
imu_bp.set_attribute('noise_gyro_stddev_x', '0.01')
imu_bp.set_attribute('noise_gyro_stddev_y', '0.01')
imu_bp.set_attribute('noise_gyro_stddev_z', '0.01')

Related Pages

Implements Principle

• Principle:CARLA_simulator_Carla_Sensor_Blueprint_Configuration