Revision history Date Doc Ver. Major Changes 2023-9-28 O01-en-230920 Corrected: Section 1.6 Specifications: • Corrected "point cloud data rate". Section 3 Data structure: • Changed the byte size of point cloud UDP data from 893 to 861. Section B.4 Laser firing time of each channel: •...
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Date Doc Ver. Major Changes Updated: Section 3.1.2.5 Tail Section B.4 Laser firing time of each channel: • ◦ Azimuth State Changed "Range: 0 to 1" to "Range: 0 to 3 (High Resolution mode)" in the field. ◦ Energy Saving Operational State Removed the option in the...
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Date Doc Ver. Major Changes 2023-12-22 O01-en-231210 Corrected: Section 1.3 Lidar structure: • Replaced the top view with bottom view to illustrate the azimuthal position and the coordinate system more clearly. Updated: Section 1.6 Specifications: • Changed the weight from 2.3 kg to 2.2 kg. Added the drawings of a new lidar exterior.
Access to this manual To obtain the latest version, please do one of the following: Contact your sales representative of Hesai. • Contact Hesai technical support team: service@hesaitech.com...
Should there be other agreements with specific users, the other agreements shall apply. • Before using a product, please confirm with Hesai the development maturity of the product in a timely manner. For products still in development, • Hesai makes no warranty of non-infringement nor assumes any responsibility for quality assurance.
If 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.
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Vibration If significant mechanical shocks and vibration exist in the product's operating environment, please contact Hesai's technical support team to • obtain the shock and vibration limits of your product model. Exposure to over-the-limit shocks or vibration may damage the product.
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.
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• To prevent breakdowns, turn off the power source before connection and disconnection. • If abnormalities already exist (such as bent pins, broken cables, and loose screws), stop using the product and contact Hesai technical support. • Eye safety The product is a Class 1 laser product. It satisfies the requirements of: IEC 60825-1:2014 •...
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• 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. • Certain product models contain high-speed rotating parts. To avoid potential injuries, do NOT operate the product if the enclosure is loose.
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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. Customized firmware and software Before using a customized version of firmware and software, please fully understand the differences in functions and performance between the •...
For product repair or maintenance issues, please contact Hesai Technology or an authorized Hesai Technology service provider. 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 injuries;...
1. Introduction 1.1. Applicable versions This manual applies to the following versions: Software 1.4.02a or later Firmware of Sensor 1.4.1t10 or later Firmware of Controller 1.4.1t3 or later 1.2. Operating principle Distance measurement: Time of Flight (ToF) A laser diode emits a beam of ultrashort laser pulses onto the target object. The laser pulses are reflected after hitting the target object.
1.3. Lidar structure Figure 1. Partial cross-sectional diagram Figure 3. Lidar azimuthal position (bottom Figure 2. Coordinate system (isometric view) view) The figures above use Exterior 1 as an example; see Section 2 Setup. The basic structure is shown in Figure 1.
1.4. Channel distribution All channels are unevenly distributed, as illustrated in Figure 4. Channel vertical distribution. Vertical resolution: See Section 1.6 Specifications. • The design values of each channel's angular position: See Appendix A Channel distribution data. • Channel Number counts from 1, top to bottom. •...
1.5. Laser firing position Figure 5. Front view (unit: mm) Figure 6. Side view (unit: mm) The figures above use Exterior 1 as an example; see Section 2 Setup. -16-...
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Each channel has an intrinsic angle offset, both horizontally and vertically. These angles are recorded in the angle correction file of this lidar, which is provided when shipping. Angle correction file In case you need to obtain the file again, please do one of the following: Send PTC command 0x05, as described in the TCP API Reference Manual (see Section 4 Communication protocol).
1.6. Specifications SENSOR Scanning method Mechanical rotation Number of channels Instrumented range 0.3 to 230 m Ranging capability ① 1 to 200 m (at 10% reflectivity) Range accuracy ② ±3 cm (3 to 200 m, typical) Horizontal FOV 360° Horizontal resolution Configurable on-the-fly 0.1°/0.2°...
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MECHANICAL/ELECTRICAL/OPERATIONAL Wavelength 905 nm Laser class Class 1 Eye Safe Ingress protection IP6K7 & IP6K9K Dimensions Height: 132.3 mm Top/bottom: Φ111.4/116.0 mm or Φ111.4/118.0 mm Rated voltage range DC 9 to 32 V Power consumption ③ 29 W Operating temperature –40℃...
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Specifications are subject to change. Please refer to the latest version. Notes to specifications ① Ranging capability (typical value) Measured under 100 klux ambient illuminance, PoD (probability of detection) • > 70%. The ranging capability of each channel is listed in Appendix A Channel •...
2. Setup Before operating the lidar, strip away the protective cover on the cover lens. 2.1. Mechanical installation 2.1.1. Lidar Exterior OT128 is switching from "Exterior 1" to "Exterior 2". Please check the delivery notice. -21-...
2.1.2. Recommended Installation Figure 11. Recommended installation (Exterior 1) The installations method for Exterior 1 and 2 are the same. The figures above use Exterior 1 as an example; see Section 2 Setup. -26-...
2.1.3. Notes on screw installation Screw type SEMS screws (with pre-attached flat washers and lock washers) are recommended. Property class should be at least 4.8. Threadlocker Before fastening a screw, apply 1 or 2 dots of threadlocker in the thread fit area. LOCTITE® 263 Threadlocker is recommended. To ensure curing it in place, wait for at least 12 hours before operating the lidar.
2.2. Electrical interface TE Connectivity part number: 2387351-1 (male socket, on the lidar) Figure 12. TE connector (male socket) 2.2.1. Pin description Signal Voltage 9 to 32 V Reserved Index 0 ~ 3.3 V Reserved Encoder 0 ~ 3.3 V MDI-P MDI-N -28-...
2.2.2. Connector use Connection Turn off the power source. Make sure the plug's red locking clip is on the same side as the socket's latch. Push the plug straight into the socket until a click is heard. Push down the red locking clip to the bottommost position until a click is heard. Disconnection Turn off the power source.
• connectors' shells, or even damage the contacts. If the connector's shell is accidentally pulled off, stop using the connector and contact Hesai technical support. • DO NOT attempt to assemble the connector's shell and cable collet; DO NOT connect a connector without its shell. Doing so may damage •...
2.3. Connection box (optional) Users may connect the lidar directly or using the connection box. The connection box has a power port and a standard Ethernet port. Figure 15. Connection box (unit: mm) -31-...
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An additional cable is used for connecting the lidar (on the left) and the connection box (on the right), as shown below. One cable's head cannot connect to another cable's tail, so each lidar can only use one cable. Figure 16.
2.3.1. Connection box ports Figure 17. Connection box (front) Port No. Port name Description Standard Ethernet port RJ45, 1000 Mbps Ethernet Power port Connects to a DC-005 DC power adapter. Reserved port Do not connect this port to external signals. -33-...
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Figure 18. Connection box (back) Port No. Port name Description Trigger port Outputs external trigger signals for multi-sensor synchronization. Power Output port See CNT3 connector in Figure 16. Cable between Lidar and connection box. Automotive Ethernet port See CNT2 connector in Figure 16.
To record and display point cloud data, see PandarView 2 User Manual. • To set parameters, check device info or upgrade firmware/software, use either LidarUtilities or PTC commands. • To obtain the SDKs (Software Development Kits) for your product model, please visit Hesai's official GitHub page: https://github.com/ • HesaiTechnology...
3.1. Point Cloud Data Packet 3.1.1. Ethernet header Default IP address: Source IP 192.168.1.201 Destination IP 255.255.255.255 Point Cloud Data Packet: Ethernet header Field Bytes Description Ethernet II MAC Destination MAC: xx:xx:xx:xx:xx:xx (FF:FF:FF:FF:FF:FF for broadcast) Source MAC: xx:xx:xx:xx:xx:xx Ethernet Data Packet Type 0x08, 0x00 Internet Protocol Protocol parameters...
3.1.2. Point cloud UDP data 3.1.2.1. Pre-Header Field Bytes Description 0xEE Start of Packet 0xFF Start of Packet Protocol Version Major Main class of the point cloud UDP packet structure Current value: 0x01 Protocol Version Minor Subclass of the point cloud UDP packet structure Current value: 0x04 Reserved -40-...
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3.1.2.2. Header Field Bytes Description Channel Num Number of laser channels Fixed: 0x80 (128) Block Num Number of block(s) per packet Fixed: 0x02 (2) First Block Return Reserved Dis Unit Fixed: 0x04 (4 mm) Return Num Maximum number of returns per channel 0x02 (2) Flags [7] to [4] are reserved...
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3.1.2.3. Body Field Bytes Description Azimuth 1 For Block 1: Current reference angle of the azimuth Unit: 0.01° Block 1 For Block 1: Measurements made by each channel (starting from Channel 1) Refer to Each block in the body. Azimuth 2 For Block 2: Current reference angle of the azimuth Block 2 For Block 2: Measurements made by each channel (starting from Channel 1)
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Each block in the body: 3 × 128 = 384 bytes Field Bytes Description Channel 1 Distance Reflectivity Measurements of Channel 1 ( Field Description 2-byte Distance Definition of the Distance field (when Up-Close Blockage Detection is OFF). 1-byte Reflectivity Range: 0 to 255 Reflectivity Reflectivity =...
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Definition of the Distance field (when Up-Close Blockage Detection is ON) Distance Description ≥ 75 Distance Dis Unit Object distance = ≥ 0.3 m Dis Unit : See Section 3.1.2.2 Header. No laser emission. Return signal is received. Object distance: < 0.3 m (below the lower limit of the lidar measurement range) Therefore, no valid point cloud output.
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3.1.2.4. Functional safety Field Bytes Description FS Version Version number of the functional safety module (currently 0x00) Lidar State [7:5] is the current Lidar State. d-0 (b-000) Initialization d-1 (b-001) Normal d-2 (b-010) Warning d-3 (b-011) Pre-Performance Degradation d-4 (b-100) Performance Degradation d-5 (b-101) Pre-Shutdown d-6 (b-110) Shutdown or Output Untrusted d-7 (b-111) Standby...
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3.1.2.5. Tail Field Bytes Description Reserved Azimuth State [15:14] is the azimuth state of Block 1, and [13:12] the azimuth state of Block 2. Used for looking up the laser firing time, see Section B.4 Laser firing time of each channel.
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Field Bytes Description Date & Time Absolute UTC of this data packet, accurate to the second. In big-endian format: Each byte Range (decimal) Year (current year minus 1900) ≥ 70 Month 1 to 12 1 to 31 Hour 0 to 23 Minute 0 to 59 Second...
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Field Bytes Description IMU Acceleration Unit Conversion factor of acceleration Data type: unsigned integer Current value: 244 (0x00F4) Unit of acceleration: 0.001mg * 244 = 0.244mg (g : standard gravity) IMU Angular Velocity Unit Conversion factor of angular velocity Data type: unsigned integer Current value: 1750 (0x06D6) Unit of angular velocity: 0.01 mdps * 1750 = 17.5 mdps (millidegree per second) IMU Timestamp...
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Field Bytes Description IMU X Axis Angular Velocity Angular velocity of the X-axis, measured by the IMU. Data type Signed integer Measurement ±500 dps range Unit of angular IMU Angular Velocity Unit See the field; currently 17.5 mdps. velocity Example When this field is 5, X-axis angular velocity = 5 ×...
3.1.3. Point cloud data analysis Take Channel 5 in Block 2 as an example: 3.1.3.1. Analyze the vertical angle of a data point The designed vertical angle of Channel 5 is 9.836°, according to Appendix A Channel distribution data. The accurate vertical angles are recorded in the angle correction file of this lidar, see Section 1.4 Channel distribution.
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3.1.3.2. Analyze the horizontal angle of a data point The Y-axis of the lidar coordinate system is 0°. The counterclockwise direction (as viewed from below) is defined as positive, see Figure 3. Lidar azimuthal position (bottom view). Horizontal angle = ① + ② ①...
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3.1.3.3. Analyze the distance of a data point Distance See the field of Block 2: Channel 5 in Section 3.1.2.3 Body. 3.1.3.4. Draw the data point in a spherical or rectangular coordinate system 3.1.3.5. Obtain the real-time point cloud data by analyzing and drawing every data point in each frame -52-...
4. Communication protocol PTC (Pandar TCP Commands) API can be used to communicate with Hesai lidars. To acquire the API reference manuals, please contact Hesai technical support. With cybersecurity enabled, the encrypted PTCS (PTC over TLS) API is also available: Data format: Same as the cleartext PTC API.
5. Sensor maintenance Stains on lidar's cover lens, such as dirt, fingerprints, and oil will negatively affect point cloud data quality. Before cleaning the cover lens, please notice: Turn OFF the power source before cleaning. • To avoid damaging the optical coating, do NOT apply pressure when wiping the cover lens. •...
6. Troubleshooting If the following procedures cannot solve your problem, please contact Hesai technical support. Points to check Symptoms Make sure that the following conditions are met: The power adapter is properly connected and in good condition; • Indicator light is off on the The connection box is intact;...
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Wireshark but not on LidarUtilities or PTC commands; PandarView 2 The latest PandarView 2 is installed on the PC (see Download page of Hesai's official website or contact Hesai • technical support). Power on again to check if the symptom persists.
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Symptoms Points to check Make sure that the following conditions are met: Ethernet cable is properly connected (by unplugging and plugging again). • The lidar's IP is in the same subnet with the PC's (WireShark may be used to check the lidar's IP that broadcasts •...
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If no packet is missing and the point cloud flashes, please update PandarView 2 to the latest version (see Download page of Hesai's official website or contact Hesai technical support); and then restart the PC. If the point cloud is still abnormal, connect the lidar to another PC and power on again to check if the symptom persists.
Appendix A: Channel distribution data Notes to the table Channel Number Counts from 1, top to bottom. Angular position The design values of each channel's horizontal (azimuth) angle offset and vertical (elevation) angle. The accurate values are recorded in this lidar unit's angle correction file. •...
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Channel Angular position Instrumented Max. range Far-field Min. detectable High- range @ 10% reflectivity enhanced? res? reflectivity at max. instrumented Horiz. offset Vertical range 0.186° 14.985° 0.3 m 130 m 60 m 100% 0.185° 13.283° 0.3 m 130 m 80 m 1.335°...
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0.127° 3.921° 1.4 m 130 m 100 m 0.127° 3.558° 0.3 m 130 m 100 m 0.107° 3.194° 1.4 m 130 m 100 m 0.106° 2.829° 1.4 m 130 m 100 m 0.105° 2.463° 1.4 m 130 m 100 m 0.105°...
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0.103° 0° 1.4 m 230 m 200 m 2.935° –0.125° 1.4 m 230 m 200 m –1.517° –0.250° 1.4 m 230 m 200 m 0.103° –0.375° 1.4 m 230 m 200 m 2.937° –0.500° 1.4 m 230 m 200 m –1.519°...
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2.948° –2.751° 1.4 m 230 m 200 m –1.526° –2.876° 1.4 m 230 m 200 m 1.324° –3.001° 1.4 m 230 m 140 m 4.570° –3.126° 1.4 m 230 m 140 m –3.155° –3.251° 0.3 m 230 m 140 m 1.325°...
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–3.167° –5.502° 1.4 m 230 m 140 m 1.329° –5.626° 1.4 m 230 m 140 m 4.588° –5.752° 1.4 m 230 m 140 m –3.168° –5.877° 1.4 m 230 m 140 m 0.102° –6.002° 0.3 m 130 m 100 m 0.103°...
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0.109° –12.709° 1.4 m 130 m 100 m 0.109° –13.075° 1.4 m 130 m 100 m 0.130° –13.439° 0.3 m 130 m 100 m 0.131° –13.803° 1.4 m 130 m 100 m 0.131° –14.164° 1.4 m 130 m 100 m 0.132°...
Appendix B: Absolute time of point cloud data B.1. Source of absolute time The lidar retrieves the current absolute time by connecting to an external clock source. B.1.1. PTP as the clock source The lidar connects to a third-party PTP master to obtain the absolute time. PTP can be configured using either LidarUtilities or PTC commands.
B.2. Absolute time of Point Cloud Data Packets The Absolute time of Point Cloud Data Packets is t , where: Date & Time • is the whole second part (see the field). Timestamp • is the microsecond part (see the field).
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High Resolution mode and Standard mode Mode Frame rate Horizontal Resolution of Far Field Measurement Standard 10 Hz 0.2° for all channels High Resolution 10 Hz 0.1° for the high-res channels (Channel 25 to Channel 88) 0.2° for the other channels 20 Hz 0.2°...
B.4. Laser firing time of each channel Given the start time (see Section B.3 Start time of each block) of Block m is T(m), m ∈ {1, 2}, the laser firing time of Channel n: Block m is t(m, n) = T(m) + Δt(n), n ∈ {1, 2, …, 128} Steps to look up firing time offsets Δt(n) Operational State Check the...
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In the ascending order of channel number (High Resolution) Azimuth State Azimuth State Channel No. Channel No. 18.867 18.867 14.231 14.231 16.375 14.231 6.289 6.289 16.549 16.549 18.693 16.549 18.867 21.011 20.52 20.52 22.664 20.52 6.289 6.289 7.942 7.942 7.942 7.942 12.578 12.578...
Appendix C: Nonlinear reflectivity mapping Reflectivity By default, the field in Point Cloud Data Packets (see Section 3.1.2.3 Body) linearly represents target reflectivity. Reflectivity • Range of the field value: 0 to 255 Range of target reflectivity: 0 to 255% •...
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Nonlinear mapping 1# Reflectivity Actual Reflectivity Actual Reflectivity Actual Reflectivity Actual field reflectivity % field reflectivity % field reflectivity % field reflectivity % 0.01 0.02 0.03 0.04 0.05 0.08 0.11 0.13 0.15 0.19 0.23 0.26 0.29 0.34 0.39 0.44 0.56 0.61 0.67 0.75...
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Reflectivity Actual Reflectivity Actual Reflectivity Actual Reflectivity Actual field reflectivity % field reflectivity % field reflectivity % field reflectivity % 10.17 10.5 10.83 11.12 11.37 11.62 11.87 12.12 12.37 12.62 12.87 13.17 13.5 13.83 14.17 14.5 14.83 15.12 15.37 15.62 15.87 16.17 16.5...
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Reflectivity Actual Reflectivity Actual Reflectivity Actual Reflectivity Actual field reflectivity % field reflectivity % field reflectivity % field reflectivity % 38.75 39.17 39.5 39.83 40.5 41.25 41.75 42.25 42.75 43.25 43.75 44.25 44.75 45.25 45.75 46.25 46.75 47.25 47.75 48.25 48.75 49.5 50.25...
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Reflectivity Actual Reflectivity Actual Reflectivity Actual Reflectivity Actual field reflectivity % field reflectivity % field reflectivity % field reflectivity % 87.75 88.5 89.25 89.75 90.5 91.5 92.5 93.25 93.75 94.5 95.5 96.25 96.75 97.5 98.5 99.5 -82-...
C.2. Nonlinear mapping 2# This mapping increases the resolution of low-reflectivity objects, especially lane markings. Figure 23. Nonlinear mapping 2# -83-...
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Nonlinear mapping 2# Reflectivity Actual Reflectivity Actual Reflectivity Actual Reflectivity Actual field reflectivity % field reflectivity % field reflectivity % field reflectivity % 2.89 4.08 5.77 6.45 7.07 7.64 8.16 8.66 9.13 9.57 10.41 10.8 11.18 11.55 11.9 12.25 12.58 12.91 13.23 13.54...
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Reflectivity Actual Reflectivity Actual Reflectivity Actual Reflectivity Actual field reflectivity % field reflectivity % field reflectivity % field reflectivity % 53.05 54.18 55.3 56.43 57.56 58.69 59.82 60.95 62.08 63.21 64.33 65.46 66.59 67.72 68.85 69.98 71.11 72.23 73.36 74.49 75.62 76.75 77.88...
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Reflectivity Actual Reflectivity Actual Reflectivity Actual Reflectivity Actual field reflectivity % field reflectivity % field reflectivity % field reflectivity % 143.34 144.47 145.6 146.73 147.86 148.98 150.11 151.24 152.37 153.5 154.63 155.76 156.88 158.01 159.14 160.27 161.4 162.53 163.66 164.79 165.91 167.04 168.17...
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Reflectivity Actual Reflectivity Actual Reflectivity Actual Reflectivity Actual field reflectivity % field reflectivity % field reflectivity % field reflectivity % 233.63 234.76 235.89 237.02 238.15 239.28 240.41 241.53 242.66 243.79 244.92 246.05 247.18 248.31 249.44 250.56 251.69 252.82 253.95 255.08 -87-...
HESAI and HESAI logo are registered trademarks of Hesai Technology. All other trademarks, service marks, and company names in this manual or on Hesai's official website are properties of their respective owners.
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Hesai Technology Co., Ltd. Phone: +86 400 805 1233 Business Email: info@hesaitech.com Website: www.hesaitech.com Service Email: service@hesaitech.com Address: Building L2, Hongqiao World Centre, Shanghai, China...
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