Hesai QT128C2X User manual

QT128C2X
128-Channel Short-Range
Mechanical Lidar
User Manual
:HEVLWH

Doc Version: Q03-en-220810
Contents
About This Manual..................................................................................... 1
Safety Notice.............................................................................................. 3
1Introduction......................................................................................... 10
1.1 Operating Principle...................................................................... 10
1.2 Lidar Structure ............................................................................. 11
1.3 Channel Distribution.................................................................... 12
1.4 Specifications............................................................................... 14
2Setup.................................................................................................... 16
2.1 Mechanical Installation................................................................ 16
2.2 Interfaces ...................................................................................... 20
2.3 Connection Box (Optional).......................................................... 23
2.4 Get Ready to Use .......................................................................... 28
3Data Structure...................................................................................... 29
3.1 Point Cloud Data Packet .............................................................. 30
4Web Control ......................................................................................... 42
4.1 Home ............................................................................................ 43
4.2 Settings .........................................................................................45
4.3 Azimuth FOV .................................................................................52
4.4 Operation Statistics......................................................................55
4.5 Upgrade ........................................................................................56
4.6 Log.................................................................................................57
4.7 Security .........................................................................................58
4.8 Login..............................................................................................63
4.9 Cybersecurity Configuration........................................................64
5Communication Protocol .................................................................... 72
6Sensor Maintenance............................................................................ 73
7Troubleshooting .................................................................................. 75
Appendix I Channel Distribution ............................................................. 79
Appendix II Absolute Time of Point Cloud Data....................................... 87
Appendix III Power Supply Requirements............................................... 96
Appendix IV Legal Notice ......................................................................... 98

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About This Manual
■ Using This Manual
·Make sure to read through this user manual before your first use and follow the instructions herein when you operate the product. Failure to
comply with the instructions may result in product damage, property loss, personal injuries, and/or a breach of warranty.
·This user manual does not contain information on product certifications. Please check the certification marks on the product's bottom
plate and read through the corresponding certification warnings.
·If you incorporate this lidar product into your product(s), you are required to provide this user manual (or the means to access this user
manual) to the intended users of your product(s)
·This lidar product is intended as a component of an end product. It shall be evaluated in end product according to relevant standards.
■ Access to This Manual
To obtain the latest version:
·Visit the Download page of Hesai's official website: https://www.hesaitech.com/en/download
·Or contact your sales representative at Hesai
·Or contact Hesai's technical support team: [e-mail]
■ Technical Support
If your question is not addressed in this user manual, please contact us at:
[e-mail]
www.hesaitech.com/en/support
https://github.com/HesaiTechnology
(Please leave your questions under the corresponding GitHub projects.)

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■ Legends
Warnings: instructions that must be followed to ensure safe and proper use of the product.
Notes: additional information that may be helpful.

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Safety Notice
■ Special Warnings
Laser Safety
Hot Surface
Hot parts!
Burned fingers when handling the parts.
Wait one-half hour after switching off before handling parts.

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Abnormalities
In any of the circumstances listed below, stop using the product immediately:
·You suspect that the product malfunctions or is damaged. For example, the product produces significant noise or is visibly vibrating.
·You or other people in the nearby environment feel discomfort.
·Any device or equipment in the nearby environment malfunctions.
Meanwhile, contact Hesai Technology or an authorized Hesai Technology service provider for more information on product disposal.
Prohibition of Disassembly
Unless expressly agreed to in writing by Hesai Technology, do NOT disassemble the product.
■ Operating Environment
Radio Frequency Interference
Before using the product, make sure to read all the signs and notices on the product enclosure (including the bottom plate). Although the
product is designed, tested, and manufactured to comply with the regulations on RF radiation (such as FCC, CE-EMC, or KCC), the radiation from
the product may still influence electronic devices.
Vibration
·If significant mechanical shocks and vibration may exist in the product's operating environment, please contact Hesai's technical support
team to obtain the shock and vibration limits of this product model. Exposure to over-the-limit shocks or vibration may damage the
product.
·Make sure to package the product in shock-proof materials to avoid damage during transport.

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Explosive Atmosphere and Other Air Conditions
·Do NOT use the product in any area where potentially explosive atmospheres are present, such as high concentrations of flammable
chemicals, vapors, or particulates (including particles, dust, and metal powder) in the air.
·Do NOT expose the product to high concentrations of industrial chemicals, including liquefied gases that are easily vaporized (such as
helium). Such exposure can damage or weaken the product's function.
Ingress Protection
Please check the product's user manual for its IP rating (refer to the Specifications section). Make sure to avoid any ingress beyond that rating.
Operating Temperature
Please check the product's user manual for its operating temperature (refer to the Specifications section). Make sure not to exceed the operating
temperature range.
Recommended Storage Conditions
Store the product in a dry, well-ventilated place. The recommended ambient temperature is 23±5°C, and the humidity between 30% and 70%.
Light Interference
Certain precision optical instruments may be interfered by the laser light emitted from the product. Please check all the instructions of these
instruments and take preventive measures if necessary. For example, when the product is temporarily not used for measurement, the protective
cover (supplied with the product) can be used to block laser light emission.

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■ Personnel
Recommended Operator Qualifications
The product should be operated by professionals with engineering backgrounds or experience in operating optical, electrical, and mechanical
instruments. Please follow the instructions in this manual when operating the product and contact Hesai technical support if needed.
Medical Device Interference
·Some components in the product can emit electromagnetic fields. If the product operators or other people in the nearby environment wear
medical devices (such as cochlear implants, heart pacemakers, and defibrillators), make sure to consult the physicians and medical device
manufacturers for medical advice, such as determining whether it is safe to work near the product.
·If you suspect that the product is interfering with your medical device, stop using the product immediately.
■ Installation and Operation
Power Supply
·You are recommended to use only the cables and power adapters provided by Hesai Technology.
·If you are to design, configure, or select the power supply system (including cables) for the product, make sure to comply with the electrical
specifications in the product's user manual (refer to the Specifications section and the Power Supply Requirements section); for technical
support, please contact Hesai Technology. Do NOT use off-spec or damaged cables or adapters.
Electrical Interface
·Before powering on the product, make sure the electrical interfaces are dry and clean. Do NOT power on the product in a humid
environment.
·Please check the Interfaces section in the product's user manual and strictly follow the instructions on plugging/unplugging the connector.
If abnormalities already exist (such as bent pins, broken cables, and loose screws), stop using the product and contact Hesai technical
support.
·To prevent breakdown, turn off the power source before connection and disconnection.

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Eye Safety
The product is a Class 1 laser product. It satisfies the requirements of:
·IEC 60825-1:2014, EN 60825-1:2014+A11:2021
·21 CFR 1040.10 and 1040.11 except for deviations (IEC 60825-1 Ed.3) pursuant to Laser Notice No.56, dated May 8, 2019.
Please follow the standard laser safety guidelines accordingly.
For maximum self-protection, it is strongly warned NOT to look into the transmitting laser through a magnifying product (microscope, eye
loupe, magnifying glass, etc.).
This product does not have a power switch. It starts operating once connected to power. During operation, the entire cover lens can be
regarded as the product's laser emitting window; looking at the cover lens can be regarded as looking into transmitting laser.
Product Enclosure
·The product contains metal, glass, plastic, as well as sensitive electronic components. In case the product has been dropped and burnt,
stop using it immediately and contact Hesai technical support.
·Do NOT squeeze or pierce the product. If the product enclosure is broken, stop using it immediately and contact Hesai technical support.
·The product contains high-speed rotating parts. To avoid potential injuries, do NOT operate the product if the enclosure is loose.
·Before operating the product, make sure it is properly and securely mounted. The mounting should prevent the product from leaving its
mounting position in case of external forces (such as collisions, high winds, and stone impacts).
·If the product enclosure consists of fins or grooves, please wear gloves when handling the product. Applying too much pressure with your
bare hands may cause cuts, bruises or other injuries.
Product Enclosure: Cover Lens
·To keep the product's cover lens from fingerprints and other stains, do NOT touch the cover lens with bare hands. If the cover lens is already
stained, please refer to the cleaning method in the Sensor Maintenance section of the user manual.
·To prevent scratches, do NOT touch the product's cover lens with hard or sharp objects. If scratches already exist, stop using the product
and contact Hesai technical support. Severe scratches may affect the quality of the product's point cloud data.

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Hot Surface
During operation or a time period after operation, the product's enclosure can be hot.
·To prevent discomfort or even burns, do NOT touch the product's enclosure with your skin.
·To prevent fires, do NOT touch the product's enclosure with flammable materials.
Peripherals
The product may be used along with accessories and devices, such as suction cup mounts, extension cables, power supplies, network devices,
GPS/PTP devices, and cleaning equipment. Please refer to all relevant specifications in the product's user manual, or contact Hesai technical
support. Using off-spec or unsuitable devices may result in product damage or even personal injuries.
Firmware and Software Upgrading
Make sure to use only the upgrade files provided by Hesai Technology. Make sure to observe all the instructions provided for that upgrade file.
Custom Firmware and Software
·Before using a custom version of firmware and software, please thoroughly understand the differences in functions and in performance
between this custom version and the standard version.
·Make sure to strictly follow all the instructions and safety precautions provided for that custom version. If the product does not function as
anticipated, stop using the product immediately and contact Hesai technical support.
Point Cloud Data Processing
The point cloud data processing features (provided on certain product models) are configurable and are intended only to assist users in
extracting information from the point cloud data. Users are in full control whether to use any of these features. Moreover, users are responsible
for analyzing the product's intended application scenarios and evaluating the risks of enabling one or more of these features in combination.
The point cloud data processing features include but are not limited to: Noise Filtering, Interstitial Points Filtering, Retro Multi-Reflection
Filtering, and Nonlinear Reflectivity Mapping.

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■ Repair and Maintenance
For product repair or maintenance issues, please contact Hesai Technology or an authorized Hesai Technology service provider. Contact
information can be found in the product's user manual (refer to the About this Manual section).
Repair
Unless expressly agreed to in writing by Hesai Technology, do NOT by yourself or entrust any third party to disassemble, repair, modify, or
retrofit the product. Such a breach:
·can result in product damage (including but not limited to water resistance failure), property loss, and/or personal injuries;
·shall constitute a breach of warranty.

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1Introduction
This manual describes the specifications, installation, and data format of QT128C2X.
1.1 Operating Principle
Distance Measurement: Time of Flight (ToF)
1) A laser diode emits a beam of ultrashort laser pulses onto the target object.
2) The laser pulses are reflected after hitting the target object. The returning beam is detected by an optical sensor.
3) Distance to the object can be accurately measured by calculating the time between laser emission and receipt.
  

d: distance
c: speed of light
t: travel time of the laser beam
Figure 1.1 Distance Measurement Using Time of Flight

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1.2 Lidar Structure
Laser emitters and receivers are attached to a motor that rotates horizontally.
Figure 1.2 Partial Cross-Sectional Diagram
Figure 1.3 Coordinate System (Isometric
View)
Figure 1.4 Default Rotation Direction
(Top View)
The lidar's coordinate system is illustrated in Figure 1.3. Z-axis is the axis of rotation.
By default, the lidar rotates clockwise in the top view. To select counterclockwise rotation, see Section 4.2 (Web Control - Settings).
The origin's exact position is shown in Figure 1.6, as a red dot. All measurements are relative to the origin.
Lidar azimuthal position is defined in Figure 1.4. Y-axis corresponds to 0°.
Each laser channel has an intrinsic azimuth offset. The horizontal center of the emitter-receiver array defines the lidar's azimuthal position.
For example, when the horizontal center passes the 90° position:
·the lidar is at the 90° position;
·the Azimuth field in the corresponding data block in the Point Cloud Data Packet will be 90°.

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1.3 Channel Distribution
The vertical resolution is unevenly distributed across all channels, as illustrated in Figure 1.5 and detailed in Appendix I (Channel Distribution).
Figure 1.5 Channel Vertical Distribution
Figure 1.6 Laser Firing Position (Unit: mm)

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Each channel has an intrinsic angle offset, both horizontally and vertically. The offsetted angles are recorded in this lidar unit's angle correction
file. In case you need to obtain the file again:
·send PTC command 0x05, as described in Hesai TCP API Protocol (Chapter 5);
·or export the file using PandarView, see the PandarView user manual;
·or contact a sales representative or technical support engineer from Hesai.
The angle correction file lists the elevation and azimuth of each channel's outgoing beam, relative to the center of the exit pupil (shown as a
yellow dot in Figure 1.6).
EEFF
1
1
LaserID
Elevation
Azimuth
1
-52.62676282
10.10830596
2
-51.0280939
9.719503673
3
-49.51495392
9.384265827
…
…
…
128
52.62676282
-10.10830596
Figure 1.7 Illustration of the Angle Correction File

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1.4 Specifications
SENSOR
Scanning Method
Mechanical Rotation
Channel
128
Instrument Range
0.05 to 50 m
Range Capability ①
Channels 9 to 120:
20 m
Channels 1 to 8, 121 to 128:
15 m
(both at 10% reflectivity)
Range Accuracy ②
±3 cm (typical)
Range Precision ②
2 cm (typical)
FOV (Horizontal)
360°
Resolution (Horizontal)
Channels 65 to 128:
0.4° (10 Hz)
0.8° (20 Hz)
Channels 1 to 64:
0.8° (10 Hz)
1.6° (20 Hz)
FOV (Vertical)
105.2° (-52.6° to +52.6°)
Resolution (Vertical)
Channels 78 to 115
0.4° to 0.5°
Other channels
0.8° to 1.6°
Frame Rate
10 Hz, 20 Hz
Return Modes
Single Return
(First, Second, Last, Strongest)
Dual Return (5 modes)
MECHANICAL/ELECTRICAL/OPERATIONAL
Wavelength
940 nm
Laser Class
Class 1 Eye Safe
Ingress Protection
IP6K7 & IP6K9K
Dimensions
Height:
83.9 mm
Top/Bottom:
Φ85.9/87.0 mm
Rated Voltage Range
DC 12 to 48 V
Power Consumption ③
12 W
Operating Temperature
-40℃ to 85℃
Storage Temperature
-40℃ to 95℃
Weight
0.7 kg
DATA I/O
Data Transmission
Ethernet (Automotive, 1000BASE-T1)
Slave Mode
Measurements
Distance, Azimuth, Reflectivity
Valid Data Points
Single Return:
864,000 points/sec
Dual Return:
1,728,000 points/sec
Point Cloud Data Rate
Single Return:
42.08 Mbps
Dual Return:
84.17 Mbps
Clock Source
PTP
PTP Clock Accuracy
≤1 μs (typical)
PTP Clock Drift ④
≤1 μs/s
Specifications are subject to change. Please refer to the latest version. (Continued on the next page)

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(Continued)
① Range Capability
· Test conditions: normal incidence, 0 to 100 klux ambient illuminance, PoD (probability of detection) > 90%, FAR (false alarm rate) < 10E-5.
· See Appendix I (Channel Distribution) for the test data of each channel.
② Range Accuracy and Range Precision
· May vary with range, temperature, and target reflectivity.
· Range accuracy: difference between the average of multiple measurements and the true value, measured under the same conditions.
· Range precision: standard deviation of multiple measurements, measured under the same conditions.
③ Power Consumption
· Not including accessories such as the connection box.
· Rated input voltage: 12 to 48 V
· Allowable input voltage: 9 to 55 V
· Refer to Appendix III (Power Supply Requirements)
④ PTP Clock Drift
· Defined as the drift at a constant temperature after the lidar (slave clock) loses connection to the PTP master.

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2Setup
2.1 Mechanical Installation
Figure 2.1 Left View (Unit: mm)

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Figure 2.2 Mounting Base (Unit: mm)

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2.1.1 Recommended Installation
Figure 2.3 Recommended Installation