RoboSense RS-Bpearl, User Manual

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RS-Bpearl User Manual
5.1.2 Data Field
Data field comprises data blocks that contain valid measurement data, in total 1200 bytes.
Each data filed contains 12 blocks, each block is 100-byte long and is a complete
measurement data set. Each data block begins with a 2-byte start identifier “0xffee”, then
a two-byte azimuth value (rotational angle). Each azimuth value records 32 sets of
channel data reported by the 32 laser channels. (Please see chapter 9 for the relationship
between channel sequence and vertical angel)
5.1.2.1 Azimuth Value
The reported azimuth is associated with the first laser firing in each sequence of laser
firings. The Azimuth Value is recorded by the encoder. The zero position on the encoder
indicates the zero degree of azimuth value on RS-Bpearl. The resolution of Azimuth is
0.01°.
For example, in Figure 8, the azimuth value is calculated through the following steps:
Get azimuth values: 0x61, 0x86
Combine to a 16 bit, unsigned integer: 0x6186 Convert to decimal: 24966
Divided by 100
Result: 249.66°
Hence
,
the firing angle is
249.66°
5.1.2.2 Channel Data
Channel Data contains 3 bytes, with the upper 2 bytes (16 bits in total) store distance
information, and the lower 1 byte contains reflectivity data. The structure of channel data
is as shown in Table 4.
Table 4
：
Channel Data Definition.
Channel data n (3 byte)
2-byte Distance 1-byte Reflectivity
Distance1 [15:8] Distance2 [7:0] Reflectivity Information
The 2-byte distance data is set in centimeter. The distance resolution is 0.5 cm. The
following shows how to parse channel data
：
For example, in the case of Figure 8, the distance information is calculated by:
Get distance values: 0x01, 0xb4.
0x01 is the upper byte of distance, concert to decimal: 1.
0xb4 is the lower byte of distance, convert todecimal: 180.
Hence, distance= upper byte of distance * 256 + lower byte of distance
= 1*256 + 180 = 436.
According to distance resolution,
the distance: 435 * 0.05 = 2.18 m
.
Hence,
the measured distance is 2.18 m
.