User Manual
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Copyright (c) 2009-2013 RoboPeak Team
Copyright (c) 2013-2016 Shanghai Slamtec Co., Ltd.
Data Processing of the Express Scan Data
By compressing the redundant data, the data response packet used in express scan
mode makes it possible to send the 4khz sampling data via the original 115200bps
bandwidth communication link. For this reason, the host system needs extra data
recovery logic to get valid measurement data.
When working in express scan mode, the measurement sampling data is stored in
the cabin structural body with two sets as unit. It includes the distance
value(distance1/distance2) and the angular compensation (
、
). The distance
value is matched with the actual distance measured in this sampling, but the angular
compensation value is not the actual angle data between the measured object and
RPLIDAR required by the host system. The final angle data can be calculated out
with the start_angle_q6 in this request. The detailed calculation method is shown as
following:
Figure 4-15 The Abstract Description for the Response Data Packet of Express Scan
Request
The above figure indicates the data response packet format of RPLIDAR in the
express scan mode. For convenience, after RPLIDAR receives the express scan
request and enter express scan mode, the first sent data response packet is denoted
as
, the second
and the i
th
. Accordingly,
indicates the actual angular physical
quantity corresponded with the start_angle_q6 field of
Since in express scan mode, the corresponding data of measurement sampling is
stored respectively and sequentially in the Cabin of each data response packet. In
every
response data, the data of the k
th
measurement sampling point is denoted
as
. It carries the distance value
and the included angle compensation
corresponded with the current measurement sampling point.
Start Express Scan Mode
S=0
…
S=1
…
S=0
…
…
The First Data Response Packet
Cabin
…