LSLIDAR CH128X1 User manual

CH128X1
User Manual
V1.0.3
2022.12
LeiShen Intelligent System Co., LTD
http://www.lslidar.com/

Safety Instruction
Before using the product, please read and follow the instructions of this manual
carefully, and refer to relevant national and international safety regulations.
∆Attention
Please do not disassemble or modify the lidar privately. If you need special
instructions, please consult our technical support staff.
∆Laser Safety Level
The laser safety of this product meets the following standards:
● IEC 60825-1:2014
● 21 CFR 1040.10 and 1040.11 standards, except for the deviations (IEC 60825-
1, third edition) stated in the Laser Notice No. 56 issued on May 8, 2019. Please
do not look directly at the transmitting laser through magnifying devices (such
as microscope, head-mounted magnifying glass, or other forms of magnifying
glasses).
Eye Safety
The product design complies with Class 1 human eye safety standards. However,
to maximize self-protection, please avoid looking directly at running products.
∆Safety Warning
In any case, if the product is suspected to have malfunctioned or been damaged,
please stop using it immediately to avoid injury or further product damage.
Housing
The product contains high-speed rotating parts, please do not operate unless
the housing is fastened. Do not use a product with damaged housing in case of
irreparable losses. To avoid product performance degradation, please do not
touch the photomask with your hands.
Operation
This product is composed of metal and plastic, which contains precise circuit
electronic components and optical devices. Improper operations such as high
temperature, drop, puncture or squeeze may cause irreversible damage to the
product.
Power Supply
Please use the connecting cable and matching connectors provided with the
lidar to supply power. Using cables or adapters that are damaged or do not meet

the power supply requirements, or supply power in a humid environment may
cause abnormal operation, fire, personal injury, product damage, or other
property loss.
Light Interference
Some precise optical equipment may be interfered with by the laser emitted by
this product, please pay attention when using it.
Vibration
Please avoid product damage caused by strong vibration. If the product's
mechanical shock and vibration performance parameters are needed, please
contact us for technical support.
Radio Frequency Interference
The design, manufacture and test of this product comply with relevant
regulations on radiofrequency energy radiation, but the radiation from this
product may still cause other electronic equipment to malfunction.
Deflagration and Other Air Conditions
Do not use the product in any area with potentially explosive air, such as areas
where the air contains high concentrations of flammable chemicals, vapours or
particles (like fine grains, dust or metal powder). Do not expose the product to
the environment of high-concentration industrial chemicals, including near
evaporating liquefied gas (like helium), so as not to impair or damage the product
function.
Maintenance
Please do not disassemble the lidar without permission. Disassembly of the
product may cause its waterproof performance to fail or personal injury.

TABLE OF CONTENTS
1. PRODUCT PROFILE .......................................................................................................................... 1
1.1 OVERVIEW ........................................................................................................................................... 1
1.2 MECHANISM ........................................................................................................................................ 1
1.3 SPECIFICATION..................................................................................................................................... 1
1.4 DIMENSIONS........................................................................................................................................ 2
2. ELECTRICAL INTERFACE .................................................................................................................4
2.1 POWER SUPPLY.................................................................................................................................... 4
2.2 ELECTRICAL INTERFACE ....................................................................................................................... 5
3. GET READY ........................................................................................................................................ 8
3.1 LIDAR CONNECTION............................................................................................................................ 8
3.2 SOFTWARE PREPARATION ................................................................................................................... 8
4. USAGE GUIDE ................................................................................................................................... 9
4.1 OPERATION UNDER WINDOWS OS ................................................................................................... 9
4.1.1 Lidar Configuration ............................................................................................................. 9
4.1.2 Windows Client Interface ................................................................................................ 10
4.1.3 Operation Procedure ........................................................................................................ 13
4.1.4 Point Cloud Data Parsing ................................................................................................. 14
4.1.5 Note....................................................................................................................................14
4.2 ROS DRIVER OPERATION UNDER LINUX OS................................................................................... 18
4.2.1 Hardware Connection and Test....................................................................................... 18
4.2.2 Software Operation Example .......................................................................................... 19
5. COMMUNICATION PROTOCOL...................................................................................................20
5.1 MSOP PROTOCOL ............................................................................................................................ 20
5.1.1 Format ................................................................................................................................ 21
5.1.2 Data Package Parameter Description.............................................................................22
5.2 DIFOP PROTOCOL............................................................................................................................ 26
5.3 UCWP PROTOCOL............................................................................................................................ 27
5.3.1 Configuration Parameters and Status Description........................................................ 28

5.3.2 Configuration Package Example...................................................................................... 30
6. TIME SYNCHRONIZATION............................................................................................................30
6.1 GPS SYNCHRONIZATION................................................................................................................... 31
6.2 EXTERNAL SYNCHRONIZATION..........................................................................................................32
6.3 GPTP SYNCHRONIZATION.................................................................................................................33
6.4 LIDAR INTERNAL TIMING ................................................................................................................... 33
7. ANGLE AND COORDINATE CALCULATION...............................................................................34
7.1 VERTICAL ANGLE ............................................................................................................................... 34
7.2 HORIZONTAL ANGLE .........................................................................................................................34
7.3 DISTANCE VALUE AND INTENSITY..................................................................................................... 35
7.4 CARTESIAN COORDINATE REPRESENTATION .................................................................................... 35
8. ACCURATE TIME CALCULATION ................................................................................................. 36
8.1 SINGLE ECHO MODE .........................................................................................................................36
8.1.1 Calculation of Data Packet End Time ............................................................................. 36
8.1.2 Accurate Time Calculation of Channel Data .................................................................. 36
8.2 DUAL ECHO MODE ........................................................................................................................... 37
8.2.1 Calculation of Data Packet End Time .............................................................................37
8.2.2 Accurate Time Calculation of Channel Data .................................................................. 37

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1. Product Profile
1.1 Overview
CH128X1 is based on the major technological breakthrough made by LeiShen
Intelligent in the miniaturization technology of auto-grade high-wire-beam
hybrid solid-state Lidar. It well meets the requirements of long-range detection
and perception performance in autonomous driving. With a compact size, which
is suitable for embedding in the roof or front protection position, this product is
more in line with the aesthetic needs of passenger vehicles’ exterior design.
1.2 Mechanism
The CH128X1 Hybrid Solid-State Lidar adopts the Time of Flight method. The
Lidar starts timing (t1) when the laser pulses are sent out. And when the laser
encounters the target object and the light returns to the sensor unit, the
receiving end stops timing (t2).
Distance = Speed of Light*(t2 – t1)/2
Figure 1.1 Mechanism of the CH128X1 Lidar
1.3 Specification
Table 1.1 Specifications of CH128X1
Model
CH128X1
Detection Method
ToF
Wavelength
905 nm
Laser Class
Class 1 (eye-safe)
Channels
128
Detection Range
200 m 160 m @10% reflectivity

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Range Accuracy
±3 cm
Data Point Generated (Single Echo Mode)
760,000 pts/sec
Vertical FOV
25° (-18°~7°)
Horizontal FOV
120°
Vertical Angular Resolution
0.125°@ROI, 0.25°@non-ROI
Horizontal Angular Resolution
5 Hz: 0.1º; 10 Hz: 0.2º; 20 Hz: 0.4º
Scanning Rate
5 Hz, 10 Hz, 20 Hz
Communication Interface
Automotive Ethernet 1000Base-1
Time Source
PPS; gPTP
Operating Voltage
9 V~36 VDC
Operating Temperature
-40℃ ~ +85℃
Storage Temperature
-40℃ ~ +105℃
Power Consumption
15W
Shock Test
500 m/sec², lasting for 11 ms
Vibration Test
5 Hz~2000 Hz, 3G rms
IP Grade
IP6K9K
Functional Safety Level
ISO26262 (ASIL B)
Dimensions
118*90*75 mm
Weight
1 kg
1.4 Dimensions
There are 4 mounting holes and 2 positioning holes at the bottom of CH128X1
Lidar. Four M5*10 (hexagon socket head cap screws) mechanical screws with
spring washers and flat washers are needed for locking and fixing the Lidar. See
the outline dimension drawing shown in Figure 1.2.
Mounting requirements: (1) Mounting screws: M5*10, hexagon socket head cap
screws; (2) Screws: GB70; (3) Spring washers: GB93; (4) Flat washers: GB93.1;
(5) Electric Torque Screwdriver: 5NM.

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Figure 1.2 CH128X1 Lidar Dimension
The CH128X1 Lidar utilizes mirror rotation and special optical design to scan
120° horizontally, with a dense light distribution of 128 lines. Figure 1.3 shows
the appearance of the CH128X1 Lidar while Figure 1.4 shows the optical center
position, which is also the coordinate origin of the host computer display
software.
Figure 1.3 External View of CH128X1

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Figure 1.4 The Optical Center of the Lidar
2. Electrical Interface
2.1 Power Supply
The power input range of the CH128X1 Lidar is 9V～36VDC. If other DC power
supply is adopted, the recommended output voltage of the power supply is
12VDC, 19VDC or 24VDC. Please note that DC 9V and 36V are short-term
power supply in extreme environment, which cannot be used as working voltage.
When the voltage output fluctuates, the Lidar may not be able to work normally.
The maximum output current should be ≥2A (the Lidar requires a large
instantaneous current when starting, and a small starting current may cause its
failure to start normally). The output ripple noise should be <120 mVp-p and
output voltage accuracy <5%. It is recommended to use 12V/3A or 24V/2A
power adapter.
The higher the power supply voltage and the stronger the discharge capacity,
the more severe the impact on the Lidar (such as powered by direct vehicle
power supply without adapters and interface boxes). Therefore, it is necessary
to use high-power TVS transient suppression diodes to protect the Lidar to avoid
damage.
The line length of the Lidar power supply is 5~10 m, and the power supply
voltage needs to be over 19V. If the line length is more than 10 m, then it is

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recommended to use a 220VAC adapter nearby for power supply (DC long-
distance power supply is not recommended).
2.2 Electrical Interface
The cables from the side of the CH128X1 lidar base are a 6-pin power supply
cable and a 2-pin automotive ethernet cable. The cables are as shown in the
figures below.
Note: There are two types of power supply cables (only differ in wire colors) for
random shipments.
Figure 2.1 The 6-PIN Power Supply Cable ①
Table 2.1 Wiring Definition of the 6-PIN Power Supply Cable ①
S/N
Color
Definition (for lidar
with CAN protocol)
Description
Definition (for lidar
with GPS time service)
Description
1
Orange
NC
-
GPS_PPS
GPS Inputting
PPS Signal
2
Red
VCC
Power+
VCC
Power+
3
Black
BATT-
Power-
BATT-
Power-
4
Light
Orange
Wake
Wake-up
Input Signal
Wake
Wake-up
Input Signal
5
Blue
CAN_H
CAN_H
GPS_GND
GPS_GND
6
Light Blue
CAN_L
CAN_L
GPS_TXD
GPS_TXD