A security-grade lidar

Abstract

This invention discloses a safety-grade lidar, which is equipped with a window detection module and a blind zone detection mechanism for real-time monitoring of the light transmittance of the light-transmitting window and the working status of the ranging loop. The lidar adopts a redundant backup design in its core processing module, input / output module, storage module, temperature sensing module, signal processing and distance calculation circuit, and motor speed acquisition method, ensuring the stability of the function implementation of each module during operation and enabling the lidar to meet safety standard requirements.

Description

Technical Field

[0001] This invention relates to the field of lidar technology, and specifically to a safety-grade lidar. Background Technology

[0002] LiDAR (Light Detection and Ranging) is a radar system that uses laser beams to detect the position, velocity, and other characteristics of a target. Its working principle involves emitting a detection signal (laser beam) towards the target, then comparing the received signal reflected back from the target (target echo) with the emitted signal. After appropriate processing, information about the target can be obtained, such as its distance, azimuth, altitude, velocity, attitude, and even shape, thereby enabling the detection, tracking, and identification of the target.

[0003] As a core sensor in AGVs / AMRs, the safety of LiDAR is critically related to the overall safety of the AGV / AMR. For example, in AGV / AMR design, the safety level of the equipment must first be determined based on its type and purpose. Then, components, especially the LiDAR, are selected according to this safety level. AGVs / AMRs that meet functional safety requirements must also use LiDARs that meet functional safety standards.

[0004] The existing safety-grade lidar in AGV / AMR systems mainly focuses on obstacle avoidance and area monitoring. The AGV / AMR system achieves these functions through three parts: detection unit, control unit, and terminal execution unit. LiDAR belongs to the detection unit, and its core function is to provide continuous, stable, and accurate switching information to indicate whether there are intruding objects in the measured space, so that the AGV / AMR system can acquire and determine whether there are intruding targets in the monitored area or whether there are obstacles in the travel route.

[0005] The IEC 61508 standard defines functional safety as follows: Functional safety is a part of equipment safety, which mainly considers the control systems related to electrical / electronic / programmable electronics (E / E / PE) and focuses on avoiding risks caused by the failure or malfunction of the controlled equipment and its related systems.

[0006] Compared to non-safety-grade LiDAR, safety-grade LiDAR has a lower and more controllable risk of failure and malfunction. Its design and implementation are based on two key aspects: First, the control and usage requirements of the external system (AGV / AMR) for the LiDAR are broken down and mapped one by one to the risk control requirements of the LiDAR's internal modules, components, and parts. The risk of each sub-item is controlled through the selection, design, and manufacturing of unit parts, components, and modules. Second, the LiDAR as a whole is considered from a macroscopic perspective, taking into account the influence of each part, component, and module on itself and their interactions. This is achieved through methods such as status monitoring, feedback control, multiple methods working together, or multiple backups using a single method to reduce the overall failure and malfunction risk of the LiDAR system.

[0007] Currently, domestic lidar systems can only achieve functional safety for some sub-functions or internal sub-units, while the application of safety-grade AGVs / AMRs requires a complete lidar system that meets safety level requirements. Summary of the Invention

[0008] The purpose of this invention is to provide a safety-grade lidar so that the entire lidar unit meets safety level requirements.

[0009] To solve the above-mentioned technical problems, the present invention provides a technical solution: a security-grade lidar, including a core processing module;

[0010] The power module, connected to the core processing module via a drive circuit, is used to provide operating voltage;

[0011] The laser source is driven and controlled by the core processing module through the light source driving circuit.

[0012] The laser beam path is arranged in sequence with a transmitting optical system, a rotating mirror, and a receiving optical system. The rotating mirror is controlled by the core processing module to change the laser emission angle. The laser emitted by the laser source is emitted through the transmitting optical system, passes through the rotating mirror, reaches the target being measured, is reflected back to the rotating mirror by the target being measured, and is then received by the receiving optical system.

[0013] The detector and conditioning circuit are used to convert the received laser into an electrical signal, which is then conditioned and transmitted to the core processing module. The core processing module then processes the signal to obtain the information of the target being measured.

[0014] The monitoring sensors include an axial angle encoder set in the rotation direction of the rotating mirror, a temperature sensing module for collecting the temperature of the detector, and a power detection unit for collecting the voltage and current information of the power module, which are respectively connected to the core processing module.

[0015] The blind zone detection mechanism is set up in the scanning blind zone of the lidar. It is used to reflect the emitted laser back to the receiving optical system when the lidar scans to the blind zone, thereby realizing the detection of the entire radar ranging link, including the transmitting optical system, rotating mirror, receiving optical system, detector and conditioning circuit, inside the radar.

[0016] The window detection module is located at the window element through which the emitted laser passes, and is used to detect the light transmittance of the window element.

[0017] The core processing module is connected to the input / output module and the storage module.

[0018] The core processing module has a backup function area, the input / output module includes at least two input / output channels, the storage module includes at least two types of memory, the temperature sensing module includes at least two temperature sensors, and the conditioning circuit includes at least two conditioning sub-circuits.

[0019] According to the above scheme, the rotating mirror is driven by a motor driven by a motor drive circuit connected to the core processing module. The blind spot detection mechanism includes a pair of reflectors set inside the upper housing. The reflective surfaces of the pair of reflectors are at a certain angle, so that when the lidar scans to the blind spot, the light beam emitted by the light source is reflected by the rotating mirror, and then reflected by the pair of reflectors before returning to the receiving field of view of the receiving optical system and being received by the detector.

[0020] According to the above scheme, the laser emission position of the safety-grade lidar is surrounded by a conical window element that allows light of a certain wavelength to be transmitted within a certain range. The window element is covered with a shielding element made of opaque material. The window monitoring module includes a detection light source set on the outer side of the bottom edge of the conical window, a light-transmitting window set above the detection light source, a reflective sheet set on the bottom surface of the shielding element, and a detection detector set on the inner side of the bottom edge of the conical window.

[0021] After the detection light source emits a detection beam, it passes through the light-transmitting window and window element, and illuminates the reflector at the bottom of the shielding element. The reflector then reflects the light to the detection detector. The transmittance of the window element is obtained by analyzing the information of the detection beam received by the detection detector.

[0022] According to the above scheme, the core processing module is a single-chip MCU. The MCU has two or more functional areas inside, and each functional area does not interfere with each other, is independent of each other, and independently implements the same core processing function; or, the core processing module includes two identical processors; or, the core processing module includes two different processors, and the two processors are programmed with different programs to implement the same function.

[0023] According to the above scheme, the core processing module collects overvoltage, overcurrent, undervoltage, and undercurrent information of the power module through the current detection unit to monitor the power module in real time; or, the core processing module directly collects the specific voltage or current values ​​of the power module to monitor the power module in real time.

[0024] According to the above scheme, the input / output module includes two different input / output channels, wherein the instruction level signals 0 / 1 transmitted by the two input channels are complementary, and the signals transmitted by the two output channels are the same.

[0025] According to the above scheme, the temperature sensing module includes two temperature sensors, wherein the two temperature sensors are the same model; or, the two temperature sensors are temperature sensors with the same temperature measurement mechanism but different models; or, the two temperature sensors are sensors that use different temperature measurement mechanisms.

[0026] According to the above scheme, the conditioning sub-circuit includes an analog front-end and a timing chip connected in series.

[0027] According to the above scheme, the storage module includes DDR memory and Flash memory.

[0028] A control implementation method for the aforementioned safety-grade lidar includes,

[0029] ① The core processing module, as the control core of the safety-grade lidar, ensures the safe implementation of control and data processing functions through redundant backups.

[0030] ② The core processing module monitors and controls each sub-module, including the laser source, motor, detector and conditioning circuit, window detection module, storage module, and power supply module, through direct connection or indirect connection with the control circuit. Each sub-module also adopts redundancy backup and diagnostic methods to ensure the safe implementation of its own functions.

[0031] ③ The core processing module monitors the radar ranging link as a whole by periodically detecting the echo of standard targets in the blind zone, ensuring the safe implementation of the radar's overall ranging function;

[0032] ④ The core processing module ensures the safe implementation of radar input and output signal functions through dual-path backup and the use of identical or complementary signals.

[0033] The beneficial effects of this invention are as follows: By employing redundant design in the core processing module, input / output module, storage module, temperature sensing module, and conditioning circuit, the stability of each module during use is ensured, thereby guaranteeing the safety requirements of the lidar. Simultaneously, the use of a window detection module and a blind zone detection mechanism enables real-time monitoring of the light transmittance of the window element and the operating status of the ranging loop, ensuring the reliability of the lidar measurement results.

[0034] Furthermore, both the blind spot detection mechanism and the window detection module are located inside the lidar, and no external detection equipment is used for detection, which reduces the space occupied by the lidar. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of a security-grade lidar structure according to an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of a blind zone detection mechanism for a safety-grade lidar according to an embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram of a window detection module of a security-grade lidar according to an embodiment of the present invention;

[0038] Figure 4 This is a schematic diagram of the electrical structure of a safety-grade lidar according to an embodiment of the present invention.

[0039] In the diagram: 100 - Two-dimensional radar system, 101 - Lower housing, 102 - Upper housing, 103 - Window element, 104 - Central rotation axis, 105 - Emitting beam, 106 - Rotating mirror, 107 - Reflected beam, 108 - Shielding element, 109 - Light source, 110 - Transmitting mirror, 111 - Motor, 112 - Mirror mount, 113 - Motor bracket, 114 - Receiving mirror, 115 - Detector, 116 - First reflector, 117 - Second reflector, 118 - Detection light source, 119 - Transmitting window, 120 - Reflector, 121 - Detection detector, 122 - Detection beam, 123 - Detection reflected beam, 124 - Normal, 125 - Circuit board. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0041] See Figure 1The two-dimensional radar system 100 includes a lower housing 101 and an upper housing 102. The lower housing 101 includes a frame structure configured to attach to a reference object (e.g., a vehicle, tower, aircraft, etc.) for which it performs LiDAR measurements. The upper housing 102 includes a window element 103 made of a material transparent to infrared light (e.g., light having wavelengths in the spectral range of 700 to 1700 nanometers) and a shielding element 108 made of a material opaque to visible and near-infrared light (e.g., light having wavelengths in the spectral range of 400 to 1700 nanometers). In one example, the window element 103 is transparent to light having a narrow wavelength range centered at 905 nanometers.

[0042] After being reflected by the rotating mirror 106, the emitted beam 105 changes its propagation direction, becoming a reflected beam 107, which is then emitted through the window element 103. The propagation direction of the emitted beam 105 coincides with the central rotation axis 104, while the propagation direction of the reflected beam 107 forms a specific angle β with the central rotation axis 104. The magnitude of β depends on the angle θ between the reflecting surface of the rotating mirror 106 and the central rotation axis 104, where β = 2θ. The angle θ is within the range of 45° ± 10°. For a specific two-dimensional radar system, θ is a constant. When θ = 45°, the rotating mirror 106 rotates around the central rotation axis 104, and the reflected beam 107 is distributed planarly in a plane passing through the reflection point and perpendicular to the central rotation axis 104. When the angle θ is within the range of 45° ± 10° and θ ≠ 45°, the reflected beam 107 is distributed conically in a conical surface with the reflection point as the vertex and the vertex angle as (180 - 4|θ - 45|). The rotating mirror 106 can rotate freely 360° around the central rotation axis 104. Within the 360° rotation range of the rotating mirror 106, the reflected beam 107 can pass through the conical portion of the window element 103 without obstruction and exit. The conical portion of the window element 103 is defined as the scanning working area, and the rotation angle range of the rotating mirror 106 that meets the condition of unobstructed exit is defined as the scanning angle range α. Within the 360° rotation range of the rotating mirror 106, when the reflected beam 107 illuminates the non-conical portion of the upper housing 102 through the window element 103, it is obstructed by the non-transparent material inside the space surrounded by the non-conical portion of the upper housing 102. The non-conical portion of the upper housing 102 is defined as the scanning blind zone, and the blind zone corresponds to the scanning angle range of 360°-α. Typically, the beam transmitted from the two-dimensional radar system 100 in the scanning working area exits into the surrounding environment and is incident on the object in the path corresponding to each scanning angle.

[0043] See Figure 2The two-dimensional radar system 100 also includes a motor 111 for driving the rotating mirror 106, a lens mount 112 for fixing the rotating mirror 106 and rotating it around the central rotation axis 104, and a motor bracket 113 for fixing the motor 111. The transmitting optical system of the two-dimensional radar system 100 includes a light source 109 and a transmitting mirror 110, and its receiving optical system includes a receiving mirror 114 and a detector 115. The blind zone detection mechanism includes a first reflecting mirror 116 and a second reflecting mirror 117 mounted on the motor bracket 113.

[0044] The rotating mirror 106 is fixed on the lens holder 112, forming a whole, and is fixedly connected to the rotor of the motor 111. The rotor of the motor 111 drives the rotating mirror 106 and the lens holder 112 as a whole to rotate relative to the motor bracket 113 around the central rotation axis 104 at a predetermined rotation speed (e.g., more than 600 revolutions per minute). The upper housing 102 is fixedly installed with a first reflector 116 and a second reflector 117 on the inner side of the corresponding blind spot area. The reflective surfaces of the first reflector 116 and the second reflector 117 are at a specific angle ψ, and the center distance between the first reflector 116 and the second reflector 117 is L.

[0045] The laser emitted from light source 109 is collimated by transmitting mirror 110 into an emitted beam 105 with a small divergence angle. When motor 111 drives rotating mirror 106 and lens mount 112 to rotate to a specific angle, the reflected beam 107 illuminates the scanning blind zone. After being reflected sequentially by first reflecting mirror 116, second reflecting mirror 117, and rotating mirror 106, it is converged onto detector 115 by receiving mirror 114. Angle ψ and distance L ensure that the light reflected by first reflecting mirror 116 and second reflecting mirror 117 falls on the reflecting surface of rotating mirror 106 and is within the receiving field of view of two-dimensional radar system 100 after reflection by rotating mirror 106 (that is, it is converged onto detector 115 via receiving mirror 114).

[0046] Furthermore, the first reflector 116 and the second reflector 117 can be integrated into a single element (such as a prism with two internal reflecting surfaces and one transmitting surface), which is fixed inside the upper housing to achieve two reflections of the reflected beam 107; even further, two planes are machined at specific positions inside the upper housing and coated with a reflective film, thereby replacing the first reflector 116 and the second reflector 117 to achieve two reflections of the reflected beam 107.

[0047] Furthermore, the reflector mount 112 and the rotating mirror 106 can be integrated into a single component (such as a module with a reflective surface and mounting holes that mate with the motor rotor).

[0048] Furthermore, the light source 109 can be a diode laser element; however, any suitable light source can generally be used, such as a fiber-fiber laser diode, fiber laser, or all-solid-state laser that meets the requirements for wavelength, repetition rate, power, size, and beam divergence angle.

[0049] See Figure 3 The two-dimensional radar system 100 also includes a detection light source 118, a light-transmitting window 119, a reflector 120, a detection detector 121, and a circuit board 125.

[0050] The detection light source 118 and the detection detector 121 are fixed on the circuit board 125. The light-transmitting window 119 is fixed on the lower housing 101, and the reflector 120 is fixed inside the shielding element 108.

[0051] The detection light source 118 emits a detection beam 122, which passes through the light-transmitting window 119 and the window element 103 and illuminates the reflector 120. The reflector 120 changes the propagation direction to form a detection reflected beam 123, which is then detected and received by the detection detector 121.

[0052] The wavelength of the light emitted from the detection light source 118 is far away from that of the light source 109 to ensure that the detection results of the detector 115 (used in conjunction with a narrowband filter) are not interfered with by the light emitted from the detection light source 118.

[0053] The light-transmitting window 119 can be an optical flat plate that does not change the wavefront of the emitted light 122, or it can be a convex lens to collimate the detection beam 122. The reflective sheet 120 can be an optical mirror or a reflective coating, or it can be a diffuse reflective material or a diffuse reflective material coating. Its reflective surface can be flat or curved (to reflect the beam 122 while changing its wavefront, making it easier for the detection detector 121 to receive it).

[0054] Furthermore, lenses are integrated into the windows of the detection light source 118 and the detection detector 121 to collimate the outgoing light from the detection light source 118 and converge the incoming light from the detection detector 121.

[0055] If the reflector 120 is a flat sheet, its position ensures that the detection beam 122 and the reflected beam 123 are specularly reflected, meaning the angle between the detection beam 122 and the normal 124 of the reflecting surface of the reflector 120 is equal to the angle between the reflected beam 123 and the normal 124. If the reflector 120 is not a flat sheet, its position and reflective surface ensure that the reflected beam 123 is detected by the detector 121 precisely when the detection beam 122 changes direction or wavefront.

[0056] The detection light source 118 and the detection detector 121 are distributed in pairs on the circuit board 125, corresponding to the conical part of the window element 103.

[0057] See Figure 4 The security features of the two-dimensional radar system 100 in this embodiment are reflected in the following aspects:

[0058] 1) Security-grade core processor

[0059] This embodiment uses a single-chip MCU as the core processor. This MCU can be internally divided into two or more functional areas, each capable of operating independently without interference, performing the same core processing functions. This ensures a high level of security through backup functional areas. Furthermore, two identical core processors can be used for backup; with the specifications unchanged, each core processor has more resources. Further, different specifications of core processors can be used; the different responses of these processors to the same external influencing factors (temperature, humidity, vibration, shock, electromagnetic environment, etc.) can further reduce the probability of failure. Even further, burning different programs into two or more core processors to achieve the same function can further enhance the security level of the radar system.

[0060] 2) Safety-grade power supply

[0061] The radar system monitors the external power supply in real time, checking whether the voltage and current exceed set thresholds to determine the operating status of the radar system's hardware circuitry and thus confirm the reliability of the output information. The radar system forms a monitoring loop with the core processor (MCU) and power module. The MCU periodically sends monitoring requests to the power module and transmits the collected overvoltage / overcurrent or undervoltage / undercurrent information back to the MCU. Furthermore, it collects specific voltage and current values ​​and sends them back to the MCU for monitoring and processing. This monitoring method offers a higher level of safety than the previous one.

[0062] 3) Safety-grade signal input and output

[0063] The radar system's input signal is the user's command to select and switch monitoring areas. To ensure signal accuracy, dual-channel simultaneous input is used, with each channel transmitting a set of commands. The 0 / 1 level signals of the two sets of commands are complementary, and mutual verification ensures the final correct input of the commands. The output indicating the presence of intruding targets or their characteristic information within the specified monitoring area is also output simultaneously through dual channels. The output information from both channels is identical to ensure that relevant alarm information regarding intruding targets is effectively output.

[0064] 4) Safety-grade ranging optical detector (monitoring and feedback control)

[0065] For the core photodetector used in ranging, its response efficiency drifts with temperature, meaning the radar system's response level fluctuates under different ambient temperatures. This embodiment uses two identical temperature sensors to monitor the detector's temperature. The temperature values ​​are fed back to the MCU, which verifies the difference between the two sensors to determine the correct temperature. Based on this, the MCU uses a voltage control circuit to adjust the photodetector's operating voltage, maintaining a stable response level. Furthermore, the two temperature sensors can be different models of temperature sensors with the same temperature measurement mechanism. Even further, two temperature sensors with different temperature measurement mechanisms can be used.

[0066] 5) Security-level signal processing and distance calculation

[0067] This embodiment employs Time-of-Flight (TOF) ranging. The optical signal received by the detector undergoes a current-to-voltage conversion and primary amplification via a transimpedance amplifier. Subsequently, the signal is split into two paths for secondary amplification and time extraction. The analog front-end (AFE) includes signal amplification and comparator functions, while the timing chip (TDC) accurately extracts the pulsed laser time of flight. The dual AFE + TDC setup effectively reduces the risk of failure in the signal processing and distance calculation circuits. Furthermore, the distance values ​​calculated from the two signals can be compared, effectively reducing the impact of optical / electrical noise and increasing data reliability.

[0068] 6) Safety-grade motor control

[0069] In this embodiment, a motor 111 drives a rotating mirror 106 for scanning. Stable motor speed is a prerequisite for stable radar system operation. This embodiment monitors the motor speed in real time using two methods: first, by obtaining the feedback current value of the motor from the motor drive circuit, and calculating the motor speed; second, by obtaining the code disk reading through a shaft angle encoder driven by the motor, and determining the motor speed. Both speed information streams are simultaneously input into the MCU. The MCU performs a comprehensive judgment to obtain the measurement value closest to the actual speed, which is used as the initial input for feedback control. The feedback control quantity is then calculated, and the motor drive circuit controls the motor to achieve stable speed operation.

[0070] 7) Security-grade ranging link (overall monitoring of ranging link).

[0071] Radar emits pulsed laser light and receives the echo laser light reflected from the target. It calculates the distance based on the time interval between the echo signal and the emitted pulse. The entire transceiver link involves a transmitting unit, a receiving unit, and a signal processing unit. Factors affecting the ranging result include the power level of the light source in the transmitting unit, the collimation characteristics of the transmitting optics, the transmittance level of the optical window, the target reflectivity, the attenuation and scattering of light by the spatial light transmission medium, the focusing characteristics of the receiving optics, the receiving response characteristics of the detector, and the signal and data processing characteristics of the amplifier circuit, comparator, and timing chip. Among these, the target reflectivity and the attenuation and scattering of light by the spatial light transmission medium are limited by the radar's external operating environment and the target being measured, exhibiting randomness and making them impossible to monitor or control. The transmittance level of the optical window is mainly determined by the type and amount of contaminants adhering to the outer surface of the optics and the integrity level of the optics. Figure 3 The structure shown performs real-time monitoring of transmittance. The light source power level, collimation characteristics of the transmitting optics, light-gathering characteristics of the receiving optics, receiving response characteristics of the detector, and signal and data processing characteristics of the amplifier circuit, comparator, and timing chip are all monitored simultaneously in this embodiment by monitoring the intensity value of the echo light signal in the dead zone. For specific implementation methods, see [link to implementation details]. Figure 2 When the motor 111 drives the rotating mirror 106 to scan to a specific angle in the blind zone, the light emitted by the radar is reflected by the reflectors (first reflector 116 and second reflector 117) at fixed positions within the blind zone, and then reflected again by the 45-degree reflector 106 and focused onto the detector 115 by the converging lens (receiving mirror 114). Based on this signal, the detector 115 calculates the intensity and range values. By comparing these intensity and range values ​​with the blind zone intensity / range calibration values ​​under ideal radar conditions, the operating status of the three functional modules of transmission, reception, and signal processing calculation under the current radar condition can be obtained.

[0072] 8) Security-grade storage devices

[0073] In this embodiment, the radar uses a Dynamic Random Access Module (DDR) and Flash memory to access temporary and permanent data. DDR and Flash, along with the MCU, form a monitoring loop. Fault avoidance measures specified in IEC61508 are used to monitor and control DDR and Flash in real time to ensure their stable operation, accurate and lossless data, and reduce the risk of failure.

[0074] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A security-grade lidar, characterized in that: Including the core processing module; The power module, connected to the core processing module via a drive circuit, is used to provide operating voltage; The laser source is driven and controlled by the core processing module through the light source driving circuit. The laser beam path is arranged in sequence with a transmitting optical system, a rotating mirror, and a receiving optical system. The rotating mirror is controlled by the core processing module to change the laser emission angle. The laser emitted by the laser source is emitted through the transmitting optical system, passes through the rotating mirror, reaches the target being measured, is reflected back to the rotating mirror by the target being measured, and is then received by the receiving optical system. The detector and conditioning circuit are used to convert the received laser into an electrical signal, which is then conditioned and transmitted to the core processing module. The core processing module then processes the signal to obtain the information of the target being measured. The monitoring sensors include an axial angle encoder set in the rotation direction of the rotating mirror, a temperature sensing module for collecting the temperature of the detector, and a power detection unit for collecting the voltage and current information of the power module, which are respectively connected to the core processing module. A blind zone detection mechanism is installed in the scanning blind zone of the lidar. It reflects the emitted laser beam back to the receiving optical system when the lidar scans into the blind zone, thereby enabling the detection of the entire lidar ranging link, including the transmitting optical system, rotating mirror, receiving optical system, detector, and conditioning circuit, within the lidar itself. The rotating mirror is driven by a motor driven by a motor drive circuit connected to the core processing module. The blind zone detection mechanism includes a pair of reflectors located inside the upper housing. The reflective surfaces of the pair of reflectors are at a certain angle, so that when the lidar scans into the blind zone, the light beam emitted by the light source is reflected by the rotating mirror, then by the pair of reflectors, and returns to the receiving field of view of the receiving optical system, where it is received by the detector. A window detection module is located at the window element through which the emitted laser passes, and is used to detect the light transmittance of the window element. The periphery of the laser emission position of this safety-grade lidar is surrounded by a conical window element that allows light of a certain wavelength to pass through. A shielding element made of opaque material is placed on top of the window element. The window monitoring module includes a detection light source located on the outer side of the bottom edge of the conical window, a light-transmitting window located above the detection light source, a reflective sheet located on the bottom surface of the shielding element, and a detection detector located on the inner side of the bottom edge of the conical window. After the detection light source emits a detection beam, it passes through the light-transmitting window and window element, and illuminates the reflector at the bottom of the shielding element. The reflector then reflects the beam to the detection detector. The transmittance of the window element is obtained by analyzing the information of the detection beam received by the detection detector. The core processing module is connected to the input / output module and the storage module. The core processing module has a backup function area, the input / output module includes at least two input / output channels, the storage module includes at least two types of memory, the temperature sensing module includes at least two temperature sensors, and the conditioning circuit includes at least two conditioning sub-circuits.

2. The security-grade lidar according to claim 1, characterized in that: The core processing module is a single-chip MCU. The MCU has two or more functional areas inside, and each functional area does not interfere with each other, is independent, and independently implements the same core processing function; or, the core processing module includes two identical processors; or, the core processing module includes two different processors, and the two processors are programmed with different programs to implement the same function.

3. The security-grade lidar according to claim 1, characterized in that: The core processing module monitors the power module in real time by collecting overvoltage, overcurrent, undervoltage, and undercurrent information from the current detection unit; alternatively, the core processing module monitors the power module in real time by directly collecting the specific voltage or current values ​​of the power module.

4. The security-grade lidar according to claim 1, characterized in that: The input / output module includes two different input / output channels. The instruction level signals 0 / 1 transmitted by the two input channels are complementary, while the signals transmitted by the two output channels are the same.

5. The security-grade lidar according to claim 1, characterized in that: The temperature sensing module includes two temperature sensors, wherein the two temperature sensors are the same model; or, the two temperature sensors have the same temperature measurement mechanism but different models; or, the two temperature sensors use different temperature measurement mechanisms.

6. The security-grade lidar according to claim 1, characterized in that: The conditioning circuitry includes an analog front-end and a timing chip connected in series.

7. The security-grade lidar according to claim 1, characterized in that: The storage module includes DDR memory and Flash memory.

8. The control and implementation method of the safety-grade lidar according to any one of claims 1 to 7, characterized in that: ① The core processing module, as the control core of the safety-grade lidar, ensures the safe implementation of control and data processing functions through redundant backups. ② The core processing module monitors and controls each sub-module, including the laser source, motor, detector and conditioning circuit, window detection module, storage module, and power supply module, through direct connection or indirect connection with the control circuit. Each sub-module also adopts redundancy backup and diagnostic methods to ensure the safe implementation of its own functions. ③ The core processing module monitors the radar ranging link as a whole by periodically detecting the echo of standard targets in the blind zone, ensuring the safe implementation of the radar's overall ranging function; ④ The core processing module ensures the safe implementation of radar input and output signal functions through dual-path backup and the use of identical or complementary signals.

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