CSCE 452/752: Notes on <div style='font-family: monospace; display:inline;'>sensor

For Project 3, you'll be using laser range finder data, represented as messages of type

sensor_msgs/LaserScan

Geometry of a
LaserScan

This data type is a bit more complicated than some others, so here's a diagram that might help you sort things out.

Note that this is a two-dimensional diagram. Perhaps the most important thing to catch is that the sensor is at the origin in frame

frame_id

, facing along the positive $x$-axis. The given

ranges

represent the measured distance to the nearest obstacle, in directions spaced evenly between

angle_min

and

angle_max

. To compute the Cartesian coordinates of these obstacles, you can use the usual trigonometric functions.