RoboSense LiDAR RS-Bpearl, Руководство пользователя

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RS-Bpearl User manual
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4.4.Laser Return Modes
4.4.1. Principle of Laser Return Modes
RS-Bpearl supports multiple laser return modes, namely: Strongest Return, Last Return and Dual
Return. When set to Dual Return mode, the details of the target will increase, and the volume of
data is twice that in the Single Return mode.
Due to beam divergence, multiple laser returns are possible from any single laser shot. A pulse
may diverge and becomes larger as it travels in the air, when a pulse is large enough to hit
multiple objects, it will produce multiple reflections. Usually, the farther away the object is, the
weaker the energy of the pulse arrived at the receiver. For bright or retroreflective surfaces, the
situation may be the opposite.
RS-Bpearl analyzes the received multiple returns, and reports the strongest return, last return or
dual returns at the same time, depending on the laser return mode settings. If the LiDAR is set to
the strongest return mode, only the value of strongest return will be reported. Similarly, if the
LiDAR is set to the last return mode, only the value of the last return will be reported. If the LiDAR
is set the dual return mode, both the strongest and last return value will be reported.
Note:
1. The sensor records both returns only when the distance between two objects is 1 meter or more.
2. When a laser pulse hits only one object, there is only the strongest return.
3. When a laser pulse hits two solid walls or other objects at two different distances, two returns will be produced.
In this case, there are two situations:
(1) When the strongest return is not the last return, the strongest and last return will be reported;
(2) When the strongest return is the last return, the strongest return and the second strongest
return will be reported.
4.4.2. Return Mode Flag
The RS-Bpearl is set in the Strongest Return mode at factory by default. If you need to change this
settings, please refer to Figure C14 in Appendix C RSView of this user manual for instructions. The
300th byte in a DIFOP packet is the flag of return mode, which corresponds to the following:
Table 4-2 Return Mode and the Corresponding Flag
Flag Return Mode
00 Dual Return
01 Strongest Return
02 Last Return