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LIDAR message

A project log for QuadRotor testBed for localization and mapping

I am trying to build a test bed for trying out localization and mapping algorithms.

int-smartint-smart 07/11/2018 at 12:140 Comments

I am planning to use ROS to interface the Lidar with the copter. The LIDAR messages are published using the message format defined in the sensor_msgs/laserscan message type in ROS. The message consists of :

std_msgs/Header header
float32 angle_min
float32 angle_max
float32 angle_increment
float32 time_increment
float32 scan_time
float32 range_min
float32 range_max
float32[] ranges
float32[] intensities

The angles are in radians. angle_min is the start angle from which the LIDAR starts taking observations in one scan. It then takes observations by incrementing the angle with steps equal to angle_increment until it reaches the angle_max when the scan completes. The time between two scan is equal to time_increment. Scan_time is the time to complete one scan in the FOV defined for the LIDAR. Range_min and range_max are the minimum and maximum values that the LIDAR can detect. Ranges give you the distance observation that has been calculated by the LIDAR.

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