The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2008
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laser scanner is feasible. The simulated test proves that it can
satisfy the needs in large range of the landslide.
Pts within +/-(2 * StdDev)
12534 (98.97%)
Pts within +/-(3 * StdDev)
12575 (99.29%)
Figure 8: Colored vectors attached to an object along the
direction of the landslide
(the first is a profile display, the second is a face display)
3.2The accuracy of the test result
In this test, it not only verifies the feasibility to monitor the
landslide but also receives the system errors of ILRIS-3D
based-ground laser scanner. The test method is explained in
2.3. The tested person moved about 1 meter along the direction
of the landslide in Y axis. It should remove the points of the
tested people and filter other noise points. At last, the point
cloud is all bare-earth points, and then compare to the twi-
scanned datum. The accuracy of the test result is listed in the
table3.
Points
12665
Mean
0.001105
StdDev
0.000997
RMS Error
0.000137
Pts within +/-(1 * StdDev)
12214(96.44%)
Table 3: the report of the accuracy (Unit: meter)
4. CONCLUSION
According to this experiment, we can draw the following basic
conclusion:
(1) Theoretically, we should carry on the long-term
observation to the mountain massif landslides. Then we
can analyze the tendency of the mountain massif
landslides from these long-term observation data and
carry on the effective monitor and the prevention. But the
price of this way in the manpower, the physical resource,
the financial resource and the time is quite high, therefore,
this paper designs this method of simulate mountain
massif landslide to carry on the monitor. The test result
proves that the way might achieve the quite accurate goal
in monitoring the landslides.
(2) The test result proves that the way of using the ground-
based 3D laser scanner to carry on the mountain massif
landslide monitoring is effective. In this test method of
the paper, we may achieve 3~5 mm precision.
(3) This way does not need to establish the vast station to
observe. By contraries, the methods of the GPS, the
geodetic survey or other “point” monitoring need to more
station to observe. The method can gain the “surface point
cloud” information about the region of the landslide very
fast, thus we may monitor the mountain massif landslide
effectively and analyze the dynamic change tendency of
mountain massif landslide. At the same time, we may
return to the original state of these mountain massif
surfaces according to “point cloud” data and carry on the
3D surveying on the surface.
(4) The ground-based 3D laser scanner is a technique of non-
contact and active remote sensing. This system can
provide the colorful images and deploy by a single
operator. The work efficiency is high and the surveyor
does not need to arrive at the dangerous region to set up
the GPS stations or the prism spots.
5. FORCAST
(1) This test was only designed one simulated landslide goal.
We will consider to setting up more stations in the
landslide region in the future, thus we might analyze the
landslide fully and effectively.
(2) Because of the funds and time, this experiment only
scanned twice to monitor the simulation landslide. In the
future we should carry on the long-term observation in
the different stations in order to achieve the goal of
dynamic monitoring.
(3) This system used in the landslide monitor is restricted by
the following factors: the available range of system,
atmospheric refraction, the reflectivity of the targets and
the penetration coefficient of systemic laser and so on.
The available range influences the precision, density and
reflectivity of the point cloud and so on. If the weather
situation is well and the observational distance is not very
far, the influence of the atmospheric refraction is not big.
The coefficient of main reflection is decided by the type