
the fourth section, it has analyzed experiments and results as well as the contribution of
the algorithm on the environment sensing of the robot; Conclusion has been conducted
in the fifth section.
2 Related Work
In the early LIDAR application, laser scanning equipment with high scanning fre-
quency was applied in detect ing land-forms under the condition of airborne. With
scanning frequency of LIDAR is high, flight speed in airborne is still fast. Thus, it’s
necessary to resolve the space attitude located by each measuring transient within the
LIDAR scanning period, so as to obtain measured data of pract ical significance [4, 5].
Unlike other distance sensors such as sonars or IR sensors, an LiDAR is capable of fine
angular and distance resolution, realtime behavior, and low false positive and negative
rates. Similar to the application of airborne laser scanning equipment, LIDAR has been
extensively used in the existing highly-efficient SLAM algorithm [6–8], serving
numerous mobile robots. With the emergence of consumer robots, LIDAR has been
developed in a low-cost plan with advantages of smaller size and lower consumption,
scanning frequency, range and samplin g points [3]. Although movement speed of the
moving robot gets faster with d ecreasing scanning frequency of LIDAR, calculation is
still conducted in scan [9] in the algor ithms of mapping, localization and obstacle
avoidance, which not only ignores the pose changes generated by movement in the
measuring process of point cloud data in the scan, but also fails in presenting correction
methods and realization means for data in the scan.
3 Correction Algorithm
3.1 Problem Describer
A common LIDAR application is presented in Fig. 1. The robot can sense the envi-
ronment by the LIDAR carried. In general, LIDAR consists of fixed part and rotational
part; the former is for fixing on the robot or other moving platform, while the latter is
for an optical path realizing 360° environment scanning with utilization of rotated
measuring units, so as to obtain environmental point cloud data of the whole plane.
LIDAR is an important sensor for the application to sense the environment. The point
cloud data obtained can construct a grid map through the SLAM algorithm. Further, the
grid map is the basis of realizing navigation and obstacles avoidance of the robot. Also,
cloud point data is important for matching with the existing map to realize the functions
like localization. In this way, the precision of point cloud data will directly affect the
realization of its dependent functions.
LIDAR is operated by scanning the whole plane environment with the optical path
via rotating the rotational part to measure distances of the measured objects at a certain
interval. Thus, measured point cloud data of the whole circle can be obtained. The
whole data with time stamp can be offered to the robot for calculation. Two extreme
cases greatly affecting the precision of LIDAR are proposed here. One is that we can
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