Environment-adaptive TDC + ADC co-processing dynamic power laser ranging system and method

Abstract

The invention discloses an environment-adaptive TDC (Time Division Converter) + ADC (Analog to Digital Converter) co-processing dynamic power laser ranging system and method. The system comprises a laser transmitting module, a variable voltage module, a laser receiving module, a TDC + ADC co-processing module, an ARM main control module and an environment adaptation module. By dynamically adjusting the laser emission power and the APD bias voltage, the optimization balance of human eye safety and distance measurement performance is realized; tDC time measurement and ADC waveform analysis are adopted for cooperative processing, so that the problem of distance measurement errors of targets with different reflectivity is effectively solved; a semiconductor refrigeration temperature control system is integrated, so that stable work in a wide temperature range from-40 DEG C to 85 DEG C is ensured; and a multistage filtering algorithm and a dynamic threshold technology are combined, so that the anti-interference capability in a complex environment is remarkably improved. The system has the advantages of high wide-temperature adaptability, high distance measurement precision, low power consumption and the like, and can be widely applied to the fields of industrial detection, automatic driving and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of laser ranging, and particularly relates to an environment-adapted dynamic power laser ranging system and method based on TDC+ADC cooperative processing. BACKGROUND

[0002] As an important means of non-contact distance measurement, laser ranging technology has been widely used in topographic mapping, industrial automation detection, security monitoring, robot navigation, automatic driving and many other fields. However, the existing laser ranging system still faces a series of technical problems to be solved in practical application, especially in complex and harsh outdoor or industrial environments: Poor wide-temperature-range adaptability: The performance of lasers, detectors and precision electronic devices is easily affected by environmental temperature. When the traditional system works in high-cold (such as -40℃) or high-temperature (such as 85℃) environments, due to the lack of effective internal temperature control mechanism, the performance of its core components will drift significantly or even fail, resulting in a significant decrease in ranging accuracy and range or the system unable to operate normally, which seriously limits its application in all-weather and all-region scenarios.

[0003] Balancing difficulty between eye safety and power consumption: In order to meet the long-range requirement, the laser emission power often needs to be increased, which directly threatens eye safety. The existing system usually adopts fixed power or simple open-loop control strategy at the emission end, either sacrificing the range and low reflectivity target detection capability to ensure safety, or increasing the risk of approaching the eye safety limit to pursue performance, and cannot dynamically adapt to different distances and reflectivity conditions, resulting in low power consumption efficiency or safety hazards.

[0004] Different reflectivity targets cause ranging errors: When the laser beam irradiates the surface of target objects with different reflectivity, the intensity of the return signal differs greatly. The existing ranging signal processing scheme (such as relying only on TDC time measurement module or analog-to-digital converter ADC) has difficulty in achieving high-precision time-of-flight (ToF) measurement or effective signal recognition when facing high-intensity saturated return or signals drowned in weak background noise, resulting in increased ranging error, especially in strong background light or complex target scenarios.

[0005] Inadequate environmental interference suppression capability: The sunlight background noise in outdoor environments, dust obstruction, and electromagnetic interference, heat radiation and other factors that may exist in industrial sites, constitute serious interference to weak laser return signals. The existing system has single or fixed parameter filtering means in software and hardware, which is difficult to adaptively eliminate these complex background noises, reducing the signal-to-noise ratio and directly affecting the ranging accuracy and reliability.

[0006] Lack of industrial-grade robustness: When used in outdoor surveying and exploration or industrial inspection, equipment often needs to withstand extreme conditions such as alternating high and low temperatures, humidity, continuous vibration, and impact. The mechanical structure design and internal component layout of traditional equipment do not fully consider the stability under impact and long-term environmental stress, which can easily lead to loose components, optical path misalignment, or even the failure of the entire system.

[0007] Therefore, developing a laser ranging system that can operate stably in an extreme wide temperature range (-40℃ to 85℃), meet human eye safety standards and low power consumption requirements, maintain high-precision measurement of targets with different reflectivities, effectively suppress complex background noise interference, and has industrial-grade shock resistance and environmental adaptability has become an urgent solution in this field to meet the increasingly demanding needs of outdoor and industrial applications. Summary of the Invention

[0008] To address the aforementioned problems in existing technologies, this invention discloses an industrial-grade laser ranging system with wide temperature range adaptability, optimized human eye safety and low power consumption, adaptive multi-target reflectivity measurement, and anti-interference capabilities. It addresses existing technologies' shortcomings in industrial-grade reliability, such as performance degradation of core components at extreme temperatures (-40℃ to 85℃), the conflict between human eye safety and measurement range power, measurement errors caused by differences in reflectivity of complex target surfaces, insufficient suppression of outdoor / industrial environmental noise, and resistance to vibration and shock. Through a dynamic temperature control architecture, intelligent power adjustment algorithm, multi-modal signal processing circuit, adaptive background noise suppression technology, and vibration-resistant and anti-loosening mechanical design, this invention achieves high-precision, high-reliability, and low-power laser ranging in all scenarios, providing a breakthrough solution for outdoor surveying, industrial inspection, and autonomous driving. The specific technical solution of the environmentally adaptable TDC+ADC collaborative processing dynamic power laser ranging system and method of this invention is as follows: An environmentally adaptable dynamic power laser ranging system with TDC+ADC collaborative processing includes a laser emitting module, a variable voltage module, a laser receiving module, a TDC time measurement and ADC module, an ARM microcontroller, a communication module, a semiconductor cooling / heating and heat dissipation module, a low-power voltage acquisition module, and a low-power temperature acquisition module. The laser emission module is connected to the variable voltage module and the ARM microcontroller, and is used to emit laser pulses to the target object; The variable voltage module is connected to the ARM microcontroller, the laser emitting module, and the laser receiving module, and is used to provide a dynamically adjustable driving voltage for the laser emitting module and the laser receiving module. The laser receiving module is connected to the TDC time measurement and ADC module to capture the weak laser echo signal reflected by the target and convert the optical signal into an electrical signal for output. The TDC time measurement and ADC module is used to measure the laser flight time, sample the echo signal intensity output by the laser receiving module, and perform waveform sampling analysis. The ARM microcontroller is used to control the light emission drive signal of the laser emitting module, control the output voltage of the variable voltage module, control the voltage of the laser receiving module, and execute a multi-mode control algorithm to dynamically control the operation of the semiconductor cooling / heating and heat dissipation module, the low-power voltage acquisition module, and the low-power temperature acquisition module. The semiconductor cooling / heating and heat dissipation module is connected to an ARM microcontroller and is used for heating and cooling the internal cavity of the product to maintain the electronic components within a certain temperature range. The low-power voltage acquisition module is connected to an ARM microcontroller and is used to acquire the output voltage of the variable voltage module. The low-power temperature acquisition module is connected to an ARM microcontroller and is used to acquire the temperature of the core components on the circuit board and the ambient temperature.

[0009] Furthermore, the laser emitting module includes a high-speed low-side gate driver, a MOSFET device, a pulsed laser diode, and a lens. The ARM microcontroller controls the switching on and off of the MOSFET device through the high-speed low-side gate driver, driving the pulsed laser diode to emit laser pulses. The variable voltage module includes a digital potentiometer and a DC-DC boost chip. Under the adjustment of the digital potentiometer, the DC-DC boost chip boosts the input voltage to the laser operating voltage, which is input to the MOSFET device to provide a stable driving power supply for the pulsed laser diode. The lens compresses the light spot and projects it onto the designated target.

[0010] Furthermore, the laser receiving module includes a lens, a boost circuit, an MS7312L module, and a CMOS operational amplifier. The MS7312L module includes an avalanche photodiode (APD), a transimpedance amplifier, and a high-speed comparator. The reflected laser spot passes through the target and returns to the laser receiving module via the lens. It is received by the avalanche photodiode (APD) on the surface of the MS7312L module and converted into an electrical signal. This signal is then amplified in two stages by the transimpedance amplifier and the CMOS operational amplifier. The boost circuit increases the supply voltage to the reverse bias voltage of the APD to ensure the linearity of the operational amplifier. The amplified signal enters the high-speed ADC acquisition module, which simultaneously triggers the TDC time measurement module to record the flight time. Under both long-distance and short-distance testing conditions, the voltage threshold Vth is controlled by an ARM microcontroller. The high-speed comparator outputs the compared echo signal based on the value of Vth.

[0011] Furthermore, the TDC time measurement and ADC module includes a TDC time measurement module and a high-speed ADC acquisition module. The TDC time measurement module is used to measure the laser flight time with high precision, and the high-speed ADC acquisition module is used to sample and analyze the echo signal intensity and waveform output by the laser receiving module at high speed.

[0012] Furthermore, the semiconductor cooling module includes a gate driver chip, an H-bridge driver circuit, an overcurrent protection circuit, a semiconductor cooling chip, and a heat sink. The semiconductor cooling chip is a TEC-type device. Combined with feedback from a low-power temperature acquisition module, the ARM microcontroller controls the H-bridge driver circuit through the gate driver chip. By controlling the current flow direction of the H-bridge, the current direction of the semiconductor cooling chip is controlled to switch between cooling and heating, maintaining the operating temperature of the core device within the set temperature range. The overcurrent protection circuit is used to monitor the current of the semiconductor cooling chip, and the heat sink is used to quickly dissipate heat from the hot end of the semiconductor cooling chip.

[0013] Furthermore, the low-power voltage acquisition module includes a MOSFET device switch and a transistor. The ARM microcontroller controls the transistor and drives the MOSFET device switch. When turned off, the standby current is ≤1μA. The low-power temperature acquisition module has the same structure as the low-power voltage acquisition module.

[0014] Furthermore, the ARM microcontroller uses a PID algorithm to control a digital potentiometer to adjust the output voltage of the DC-DC boost chip, thereby dynamically adjusting the voltage driving the laser; it receives time difference data from the TDC time measurement module and combines it with amplitude information from the high-speed ADC acquisition module, using a combination of dynamic filtering and slope to dynamically compensate for ranging errors under different reflectivities.

[0015] This invention also discloses a control method for an environmentally adaptable dynamic power laser ranging system with TDC+ADC collaborative processing, comprising the following steps: Step 1: System Initialization: The ARM microcontroller performs hardware initialization configuration and software parameter setting, including software initialization of the ARM microcontroller and the TDC time measurement module; Step 2: Temperature / Voltage Acquisition: The ARM microcontroller controls the low-power temperature acquisition module to acquire the temperature near the TDC time measurement module; the ARM microcontroller controls the low-power voltage acquisition module to acquire the voltage driving the laser emission and the reverse bias voltage of the APD, respectively. Step 3: Temperature Adjustment: The ARM microcontroller executes temperature control logic based on the temperature information collected by the low-power temperature acquisition module, drives the semiconductor cooling / heating and heat dissipation module to work, and adjusts and maintains the temperature of the core components of the system within the preset working range. Step 4: Laser emission power adjustment: Based on the preset target power or according to environmental parameters, drive the power adjustment mechanism of the laser emission module to dynamically adjust the driving laser emission voltage according to the intensity of the collected echo signal and the initial distance, so as to ensure the stability and intensity of the emitted light signal and reduce the power consumption of the system. Step 5: APD voltage adjustment: The reverse bias voltage of the avalanche photodiode (APD) that receives the optical signal is dynamically adjusted according to a preset value or real-time acquired parameters to improve the detection sensitivity and responsivity of the optical signal. Step 6: TDC Data Processing: Receive raw data from the TDC time measurement module, which represents the time interval between the laser emission pulse and the received return pulse; perform data processing operations; Step 7: ADC Data Processing: Receive raw data from the high-speed ADC acquisition module, which characterizes the intensity of the analog echo signal output by the avalanche photodiode (APD); perform data processing operations. Step 8: Error Compensation Scheme: Based on the processed TDC time measurement module data, high-speed ADC acquisition module data, and real-time acquired temperature / voltage information, execute the error compensation algorithm to calculate and correct the measurement error caused by the difference in reflectivity between the measured object and the target object, and generate a more accurate core value of flight time or distance data. Step 9: Output Results: Output the final measurement results after error compensation through a predetermined interface or communication protocol; Step 10: Loop Judgment: After completing the result output step, perform a logical judgment to determine whether the measurement process should continue to a new round of measurement; when the judgment result is "yes", return to step 2 to perform temperature / voltage acquisition and start a new round of measurement loop; when the judgment result is "no", enter the end state.

[0016] Furthermore, the data processing flow of the TDC time measurement module specifically includes the following steps: Step 1: System pre-initialization phase: Hardware reset and configuration layer: The ARM microcontroller sends a hardware reset command to the high-speed low-side gate driver and the TDC time measurement module; the ARM microcontroller configures the port function and writes the TDC control register parameters. Step 2: Pulse Sequence Emission and Raw Data Acquisition. The high-speed low-side gate driver is triggered via the GPIO interface of the ARM microcontroller to continuously emit Ms groups of laser pulses at fixed time intervals Δt; the output of the TDC time measurement module is captured in real time. Ms The time register (reg) data is grouped, and each group of reg values ​​is the raw quantized value of the flight time of a single laser pulse from emission to reception. Step 3: Data Classification and Outlier Identification: Statistics Ms The frequency of duplicate values ​​in the group reg data; if the frequency of duplicates exceeds a threshold.Ka The system determines that there is out-of-bounds interference; multi-level data cleaning: out-of-bounds situation: location deviation from the median ± Kc Data points are processed by removing all outliers; in the non-out-of-bounds case, the central distribution range of the dataset is preserved; extreme value filtering removes the subset of maximum values ​​from the valid dataset. Ma and minimum subset Mb Eliminate accidental measurement bias; Step 4: Dynamic Filtering and Feature Extraction First-order infinite impulse response (IIR) filtering is applied to the remaining cleaned dataset: y [ n ] =β⋅x [ n ] + ( 1−β ) ⋅y [ n−1 ] (0.1≤ β ≤0.35) in x [ n [ represents the current input value] y [ n−1 [This refers to historical output values.] β Adaptive adjustment to balance noise suppression and response speed; Step 5: Calculate the sliding window mean of the filtering results and output the optimized overall reg value; Step 6: Distance calculation and environmental compensation; Substitute the reg value into the flight time-distance conversion formula and perform temperature drift compensation. By collecting temperature sensor data, the distance value is corrected through a nonlinear correction model. Step 7: Loop control logic; judge the user command or timer flag. If continuous measurement is required, return to step 2 to start a new round of pulse sequence; otherwise, enter sleep mode and turn off the laser drive power supply.

[0017] Furthermore, the ADC module data processing flow specifically includes the following steps: Step 1: System Initialization Phase Hardware co-booting: Reset the ARM microcontroller and high-speed ADC acquisition module, configure direct memory access channel parameters, and set the sampling depth. Amn The group has a continuous waveform storage space, in which m × n matrix, m ≥10, n ≥10; Initialize the high-speed comparator threshold voltage Va ( th ), calibrate the trigger timing of the laser emission synchronization signal; Step 2: Waveform Acquisition and Storage: The laser echo signal is acquired at a fixed sampling rate using a high-speed ADC acquisition module. Each round of acquisition... Amn Collect the original voltage waveform data; enable DMA double buffering mechanism, and... Amn Data is transmitted to the memory array without loss, avoiding signal distortion caused by interrupt delays in the ARM microcontroller; Step 3: Multi-level data cleaning: Peak anomaly removal: Scanning Amn Data matrix, identify and remove two types of outlier subsets: maximum value outliers. Ad The peak value of the waveform exceeds the upper limit of the physical range. Ad Group data distortion anomaly set Ac : Delete the data with the largest / smallest peak values ​​from the remaining data. d Group data and c Suppressing occasional noise interference; Step 4: Waveform Reconstruction and Feature Extraction: After cleaning... A ( m-d-c ()( n-d-c The data matrix is ​​averaged point by point to generate a synthesized waveform array with enhanced noise resistance. Step 5: Dynamic error modeling; calculate comparator threshold voltage Va ( th ) and peak voltage Vap slope factor Vk ; Step 6: Distance calculation and output; Vk Substituting these values ​​into a nonlinear error mapping table, which is a discrete table based on actual measurements, we select multiple sets of targets with different reflectivities at different distances through measurements, and obtain the slope of the echo waveform at different reflectivities. Vk Index out the corresponding distance compensation amount Sm Output the compensated distance value; Step 7: Loop Control: If the continuous measurement flag is activated, return to Step 2 to start a new round of acquisition; otherwise, turn off the laser power and enter low-power standby mode.

[0018] The environmentally adaptable TDC+ADC collaborative processing dynamic power laser ranging system and method of the present invention has the following advantages: 1. Extreme wide temperature range adaptability: Integrating a semiconductor cooling module and a temperature closed-loop control algorithm to achieve... The cavity temperature remains dynamically stable in environments ranging from -40℃ to 85℃, ensuring the reliable and stable performance of core components such as lasers, detectors, and TDC time measurement modules, thus overcoming the reliability bottleneck of traditional equipment in extremely cold / high temperature scenarios.

[0019] 2. Coordinated optimization of human eye safety and low power consumption: The closed-loop power adjustment technology based on echo signal strength feedback is adopted and combined with dynamic range algorithm to achieve on-demand adjustment of transmission power while ensuring compliance with human eye safety standards, and at the same time improve the detection capability of low reflectivity targets.

[0020] 3. High-precision ranging for targets with high reflectivity: The first-ever TDC+ADC collaborative high-speed acquisition architecture, through the fusion processing of hardware-level time measurement and signal amplitude analysis, automatically switches the ranging mode: for high reflectivity targets, the TDC time measurement module is used for high-precision timing, and for low reflectivity targets, the ADC module is used for signal reconstruction, so that the ranging error of targets with different reflectivity is controlled within the centimeter level.

[0021] 4. Anti-interference capability in complex environments: An adaptive background noise suppression algorithm has been developed, which combines multi-level programmable filters and dynamic threshold adjustment technology to effectively eliminate the effects of sunlight, electromagnetic interference and thermal radiation, improve the signal-to-noise ratio by more than 20dB, and maintain ranging accuracy under strong background light or dust conditions. Attached Figure Description

[0022] Figure 1 This is a system composition block diagram of the present invention; Figure 2 This is a schematic diagram of the hardware process for the laser ranging function of the present invention; Figure 3 This is a block diagram of the laser emitting module and the variable voltage module of the present invention; Figure 4 This is a block diagram of the laser receiving module of the present invention; Figure 5 This is a block diagram of the semiconductor cooling and heat dissipation module of the present invention; Figure 6 This is a block diagram of the low-power voltage / temperature acquisition module of the present invention; Figure 7 This is a flowchart of the system software of the present invention; Figure 8 This is a flowchart of the data processing of the TDC time measurement module implemented by the software of this invention; Figure 9 This is a flowchart of the data processing of the ADC module implemented by the software of this invention. Detailed Implementation

[0023] To better understand the purpose, structure, and function of this invention, the following detailed description, in conjunction with the accompanying drawings, provides an environmentally adaptable dynamic power laser ranging system and method with TDC+ADC collaborative processing.

[0024] like Figure 1As shown, the environmentally adaptable TDC+ADC collaborative processing dynamic power laser ranging system of the present invention includes a laser emitting module 01, a variable voltage module 02, a laser receiving module 03, a TDC time measurement and ADC module 04, an ARM microcontroller 05, a communication module 06, a semiconductor cooling / heating and heat dissipation module 07, a low-power voltage acquisition module 08, and a low-power temperature acquisition module 09.

[0025] Laser Emission Module 01: The laser emission module 01 is connected to the variable voltage module 02 and the ARM microcontroller 05. The laser emission module emits laser pulses with a wavelength of 905nm to the target object. The variable voltage module adopts an adjustable power design. Under the control of the ARM microcontroller 05, the emission power is dynamically adjusted according to the target distance and reflectivity, avoiding the insufficient long-distance detection capability or the safety risk to the human eye at close range caused by the traditional fixed power mode.

[0026] Variable voltage module 02: Variable voltage module 02 is connected to ARM microcontroller 05, laser emitting module 01, and laser receiving module 03. Variable voltage module 02 provides dynamically adjustable drive voltage to laser emitting module 01 and laser receiving module 03. The voltage change of variable voltage module 02 is dynamically adjusted and controlled by ARM microcontroller 05. When detecting distant, weakly reflective targets, variable voltage module 02 boosts the signal; when detecting close-range, highly reflective targets, variable voltage module 02 reduces the voltage to ensure eye safety and reduce power consumption.

[0027] Laser receiver module 03: Laser receiver module 03 is connected to TDC time measurement and ADC module 04. It is used to capture the weak laser echo signal reflected from the target and convert the optical signal into an electrical signal for output.

[0028] TDC Time Measurement and ADC Module 04: This module includes a TDC time measurement module (MS1003 module) 18 and a high-speed ADC acquisition module 19. The TDC time measurement and ADC module 04 is connected to an ARM microcontroller 05 and a laser receiving module 03. The TDC time measurement module 18 is used for high-precision measurement of laser time of flight, and the high-speed ADC acquisition module 19 is used for high-speed sampling and waveform analysis of the echo signal strength output by the laser receiving module. Hybrid logic control: Covering total reflectivity scenarios, for strongly reflective targets (such as mirrors or white objects), the TDC time measurement module 18 takes the lead: directly measuring the time of flight (ToF) of the laser pulse, avoiding timing errors caused by ADC signal saturation. Circuit implementation: The TDC time measurement module 18 is triggered by a high-speed comparator to avoid nonlinear distortion of analog circuits. For weakly reflective targets (such as black objects or distant objects), the high-speed ADC acquisition module 19 takes the lead: high-speed sampling of the echo waveform (≥100MSPS), extracting the effective signal submerged in noise through digital signal processing. It automatically amplifies weak signals to improve ADC quantization accuracy. It effectively reduces the problem of ranging error under different reflectivities at the same distance, and improves the accuracy of ranging.

[0029] ARM microcontroller 05 controls the light emission drive signal of laser emission module 01. It controls the digital potentiometer 13 in variable voltage module 02, dynamically adjusting the output voltage of variable voltage module 02 via the IIC interface. The ARM microcontroller also dynamically adjusts the output voltage of Boost circuit 10 via PWM duty cycle. ARM microcontroller 05 loads system programs, mainly including module control programs and data processing programs. Data from TDC time measurement and ADC module 04 is input to ARM microcontroller 05, which executes a multi-mode control algorithm (reg data processing, echo waveform analysis, ranging calculation, power adjustment, temperature compensation) to dynamically control the operation of semiconductor cooling / heating and heat dissipation module 07, low-power voltage acquisition module 08, and low-power temperature acquisition module 09. ARM microcontroller 05 sends ranging data to the user via communication module 06, including wired UART or wireless WIFI modes.

[0030] Communication Module 06: Used to output ranging results to a host computer or cloud via an isolation circuit. Protocol Support: Industrial standard interfaces such as UART / WIFI.

[0031] Semiconductor cooling / heating and heat dissipation module 07: Used for heating and cooling the internal cavity of the product, maintaining electronic components within a certain temperature range. Semiconductor cooling / heating and heat dissipation module 07 is connected to ARM microcontroller 05. ARM microcontroller 05 controls the H-bridge drive circuit 25 of semiconductor cooling / heating and heat dissipation module 07: By controlling the current flow direction of the H-bridge, it controls the current direction of the semiconductor cooling chip 24 (TEC) for switching between cooling and heating.

[0032] Low-power voltage acquisition module 08: This low-power voltage acquisition module is connected to the ARM microcontroller 05 and is used to acquire the output voltage of the variable voltage module 02. It features an ultra-low power design, with a standby current ≤1μA, and supports intermittent operation mode (extending the battery life of outdoor equipment).

[0033] Low-power temperature acquisition module 09: This low-power temperature acquisition module connects to the ARM microcontroller 05 and is used to acquire the temperature of core components on the circuit board and the ambient temperature. It features an ultra-low power design, with a standby current ≤1μA, and supports intermittent operation mode (extending the battery life of outdoor equipment).

[0034] Combination Figures 2-6 The working process of laser ranging is described as follows: (1) Laser emission: such as Figure 2 Figure 3 As shown, the laser emission module 01 includes a high-speed low-side gate driver 15, a MOSFET device 16, a pulsed laser diode 17, and a lens 20. The ARM microcontroller 05 controls the switching on and off of the MOSFET device 16 via the high-speed low-side gate driver 15, driving the pulsed laser diode 17 to emit laser pulses with a wavelength of 905nm and a pulse width of 5-100ns. The variable voltage module 02 includes a digital potentiometer 13 and a DC-DC boost chip 14. Under the adjustment of the digital potentiometer 13, the DC-DC boost chip 14 boosts the input voltage to the laser operating voltage, which is then input to the MOSFET device 16 to provide a stable driving power supply for the pulsed laser diode 17. The lens 20 compresses the light spot and directs it onto the designated target. The MOSFET device 16 adopts an N-channel enhancement-mode structure to ensure a nanosecond-level response speed.

[0035] (2) Implementation of echo reception and processing: such as Figure 2 Figure 4As shown, the laser receiving module 03 includes a lens 21, a boost circuit 10, an MS7312L module 11, and a CMOS operational amplifier 12. The MS7312L module 11 includes an avalanche photodiode (APD), a transimpedance amplifier (TIA), and a high-speed comparator. After the reflected laser spot passes through the target and returns to the laser receiving module 03 via the lens 21, it is received by the avalanche photodiode (APD) on the surface of the MS7312L module 11 and converted into an electrical signal. This signal is then amplified in two stages by the transimpedance amplifier (TIA) and the CMOS operational amplifier 12 (first stage gain 10dB, second stage gain 20dB). The boost circuit 10 boosts the supply voltage to the reverse bias voltage of the APD, ensuring the linearity of the operational amplifier. The amplified signal enters the high-speed ADC acquisition module 19, synchronously triggering the TDC time measurement module 18 to record the time of flight. In both long-range and short-range testing scenarios, the voltage threshold Vth is controlled by the ARM microcontroller 05, and the high-speed comparator outputs the compared echo signal based on the value of Vth.

[0036] (3) Implementation of the main control unit: The ARM microcontroller 05 running system realizes the following core functions: The output voltage of the DC-DC boost chip 14 is adjusted by controlling the digital potentiometer 13 through the PID algorithm, and the voltage driving the laser is dynamically adjusted. The time difference data of the TDC time measurement module 18 is received and combined with the amplitude information of the high-speed ADC acquisition module 19. The dynamic filtering and slope combination method is used to dynamically compensate for the ranging error under different reflectivities.

[0037] (4) Implementation of functional modules such as data acquisition and temperature control: such as Figure 5 As shown, the semiconductor cooling module 07 includes a gate driver chip 22, an H-bridge driver circuit 25, an overcurrent protection circuit 26, a semiconductor cooling chip 24, and a heat sink 23. The semiconductor cooling chip is a TEC-type device. Combined with feedback from the low-power temperature acquisition module 09, the ARM microcontroller 05 controls the H-bridge driver circuit 25 through the gate driver chip 22. By controlling the current flow direction of the H-bridge, it controls the current direction of the semiconductor cooling chip 24 to switch between cooling and heating, maintaining the operating temperature of the core components within the set temperature range. The overcurrent protection circuit 26 monitors the current of the semiconductor cooling chip 24 to prevent damage to the device due to short circuits or overloads. The heat sink 23 quickly dissipates heat from the hot end of the semiconductor cooling chip, preventing high temperatures from affecting performance.

[0038] like Figure 6As shown, the low-power voltage acquisition module 08 is connected to the ARM microcontroller 05 and is used to acquire the output voltage of the variable voltage module 02. The low-power voltage acquisition module 08 adopts an ultra-low power design. It includes a MOSFET switch 27 and a transistor 28. The ARM microcontroller 05 controls the transistor 28 and drives the MOSFET switch 27. When turned off, the standby current is ≤1μA. The low-power temperature acquisition module 09 has the same structure as the low-power voltage acquisition module 08. It is connected to the ARM microcontroller 05 and is used to acquire the temperature of the core components on the circuit board and the ambient temperature. It features an ultra-low power design, with a standby current ≤1μA, and supports intermittent operation mode (extending the battery life of outdoor equipment).

[0039] like Figure 7 The system software flowchart of this invention includes the following steps: (1) System initialization: The ARM microcontroller 05 performs hardware initialization configuration and software parameter setting to prepare for the subsequent laser measurement process, including the software initialization of the ARM microcontroller 05 and the TDC time measurement module 18; (2) Temperature / Voltage Acquisition: Responsible for real-time acquisition of temperature information of key system components and operating voltage information of the laser emission power circuit; low-power temperature acquisition module 09 mainly acquires the temperature near TDC time measurement module 18. Low-power voltage acquisition module 08 acquires the voltage driving laser emission and the reverse bias voltage of APD respectively. Low-power voltage acquisition module 08 and low-power temperature acquisition module 09 are designed as low-power circuits. Both low-power voltage acquisition module 08 and low-power temperature acquisition module 09 are driven and controlled by ARM microcontroller 05. When it is not necessary to acquire voltage and temperature signals, the low-power voltage acquisition module 08 and low-power temperature acquisition module 09 have low power consumption, effectively reducing system power consumption.

[0040] (3) Temperature regulation: The ARM microcontroller 05 executes temperature control logic based on the temperature information collected by the low-power temperature acquisition module 09, drives the semiconductor cooling / heating and heat dissipation module 07 to work, and adjusts and maintains the temperature of the core components of the system within the preset working range. (4) Laser emission power adjustment: Based on the preset target power or according to environmental parameters (such as temperature), drive the power adjustment mechanism of the laser emission module 01 to dynamically adjust the driving laser emission voltage according to the intensity of the collected echo signal and the initial distance, so as to ensure the stability and intensity of the emitted light signal and reduce the power consumption of the system. (5) APD voltage adjustment: The reverse bias voltage of the avalanche photodiode (APD) that receives the optical signal is dynamically adjusted according to the preset value or the parameters collected in real time (such as temperature, echo signal intensity estimation) to improve the detection sensitivity and responsivity of the optical signal. (6) TDC data processing: Receive raw data from the time-to-digital converter (TDC time measurement module 18), which represents the time interval between the laser emission pulse and the received return pulse; perform data processing operations, including but not limited to: signal filtering, noise suppression, and time extraction; (7) ADC data processing: Receive raw data from the analog-to-digital converter (high-speed ADC acquisition module 19), which represents the intensity of the analog echo signal output by the APD or other analog parameters (received light intensity value); perform data processing operations, including but not limited to: signal amplification, filtering, and digital conversion; (8) Error compensation scheme: Based on the processed TDC time measurement module 18 data, high-speed ADC acquisition module 19 data and real-time acquired temperature / voltage information, execute the error compensation algorithm to calculate and correct the measurement error caused by factors such as temperature drift, circuit noise, device aging, nonlinearity and the difference in reflectivity of the measured object, and generate a more accurate core value of flight time or distance data. (9) Output of results: Output the final measurement results (such as distance value, status information) after error compensation through a predetermined interface or communication protocol; (10) Loop judgment: After completing the result output step, perform a logical judgment to determine whether the measurement process should continue to a new round of measurement; when the judgment result is "yes", return to step (2) to perform temperature / voltage acquisition and start a new round of measurement loop; when the judgment result is "no", enter the end state.

[0041] like Figure 8 The software implementation of the TDC time measurement module data processing flowchart of this invention includes the following steps: (1) System pre-initialization stage: Hardware reset and configuration layer: ARM microcontroller 05 sends hardware reset command to high-speed low-side gate driver and TDC time measurement module 18; configure port function through ARM microcontroller 05 and write TDC control register parameters; (2) Pulse sequence transmission and raw data acquisition: The high-speed low-side gate driver is triggered by the GPIO interface of the ARM microcontroller 05 to continuously transmit Ms groups of laser pulses (Ms≥20) at a fixed time interval Δt; the Ms group time register (reg) data output by the TDC time measurement module 18 is captured in real time, and the value of each group of reg is the raw quantized value of the flight time of a single laser pulse from transmission to reception; (3) Data hierarchical processing and outlier identification: statistics Ms The frequency of duplicate values ​​in the group reg data; if the frequency of duplicates exceeds a threshold. Ka The system determines that there is out-of-bounds interference; multi-level data cleaning: out-of-bounds situation: location deviation from the median ± KcData points are processed by removing all outliers; in the non-out-of-bounds case, the central distribution range of the dataset is preserved; extreme value filtering removes the subset of maximum values ​​from the valid dataset. Ma and minimum subset Mb Eliminate accidental measurement bias; (4) Dynamic filtering and feature extraction First-order infinite impulse response (IIR) filtering is applied to the remaining cleaned dataset: y [ n ] =β⋅x [ n ] + ( 1−β ) ⋅y [ n−1 ] (0.1≤ β ≤0.35) in x [ n] This is the current input value. y [ n−1 [This refers to historical output values.] β Adaptive adjustment to balance noise suppression and response speed; (5) Calculate the sliding window mean of the filtering results and output the optimized comprehensive reg value; (6) Distance calculation and environmental compensation; Substitute the reg value into the flight time-distance conversion formula (the calculation formula corresponding to the reg value and the actual distance). Perform temperature drift compensation by collecting temperature sensor data and correcting the distance value through a nonlinear correction model; (7) Loop control logic; judge the user command or timer flag. If continuous measurement is required, return to step (2) to start a new round of pulse sequence; otherwise, enter sleep mode and turn off the laser drive power supply. like Figure 9 The flowchart of the software implementation of ADC module data processing in this invention includes the following steps: (1) System initialization phase: Hardware co-boot: Reset the ARM microcontroller 05 and high-speed ADC acquisition module 19, configure the direct memory access (DMA) channel parameters, and set the sampling depth to [value missing]. Amn Group( m × n matrix, m ≥10, n ≥10) continuous waveform storage space; initialize high-speed comparator threshold voltage Va ( th ), calibrate the trigger timing of the laser emission synchronization signal; (2) Waveform Acquisition and Storage: The laser echo signal is acquired at a fixed sampling rate through the high-speed ADC acquisition module 19. Each round of acquisition...Amn Collect the original voltage waveform data; enable DMA double buffering mechanism, and... Amn Data is transmitted to the memory array without loss, avoiding signal distortion caused by interrupt delay of the ARM microcontroller 05; (3) Multi-level data cleaning: Peak anomaly removal: scanning Amn Data matrix, identify and remove two types of outlier subsets: maximum value outliers. Ad The waveform peak value exceeds the upper limit of the physical range. Ad Group data distortion anomaly set Ac : Delete the data with the largest / smallest peak values ​​from the remaining data. d Group data and c To suppress occasional noise interference.

[0042] (4) Waveform reconstruction and feature extraction: for the cleaned waveform A ( m - d - c ()( n - d - c The data matrix is ​​averaged point by point to generate a synthesized waveform array with enhanced noise resistance. (5) Dynamic error modeling; calculation of the threshold voltage of the high-speed comparator Va (th) and peak voltage Vap slope factor Vk ; (6) Distance calculation and output; Vk Substituting these values ​​into a nonlinear error mapping table, which is a discrete table based on actual measurements, we select multiple sets of targets with different reflectivities at different distances through measurements, and obtain the slope of the echo waveform at different reflectivities. Vk Index out the corresponding distance compensation amount. Sm Output the compensated distance value; (7) Cyclic control: If the continuous measurement flag is activated, return to step (2) to start a new round of acquisition; otherwise, turn off the laser power supply and enter low power standby mode.

[0043] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. An environmentally adaptable dynamic power laser ranging system with TDC+ADC collaborative processing, characterized in that, Includes a laser emitting module (01), a variable voltage module (02), a laser receiving module (03), a TDC time measurement and ADC module (04), an ARM microcontroller (05), a communication module (06), a semiconductor cooling / heating and heat dissipation module (07), a low-power voltage acquisition module (08), and a low-power temperature acquisition module (09). The laser emitting module (01) is connected to the variable voltage module (02) and the ARM microcontroller (05) and is used to emit laser pulses to the target object; The variable voltage module (02) is connected to the ARM microcontroller (05), the laser emitting module (01), and the laser receiving module (03), and is used to provide dynamically adjustable driving voltage for the laser emitting module (01) and the laser receiving module (03); The laser receiving module (03) is connected to the TDC time measurement and ADC module (04) to capture the weak laser echo signal reflected by the target and convert the optical signal into an electrical signal for output. The TDC time measurement and ADC module (04) is used to measure the laser flight time, sample the echo signal intensity output by the laser receiving module (03), and perform waveform sampling analysis. The ARM microcontroller (05) is used to control the light emission driving signal of the laser emitting module (01), control the output voltage of the variable voltage module (02), control the voltage of the laser receiving module, and execute the multi-mode control algorithm to dynamically control the operation of the semiconductor cooling / heating and heat dissipation module (07), the low-power voltage acquisition module (08), and the low-power temperature acquisition module (09). The semiconductor cooling / heating and heat dissipation module (07) is connected to the ARM microcontroller (05) and is used for heating and cooling the inner cavity of the product to maintain the electronic components within a certain temperature range. The low-power voltage acquisition module (08) is connected to the ARM microcontroller (05) and is used to acquire the output voltage of the variable voltage module (02); The low-power temperature acquisition module (09) is connected to the ARM microcontroller (05) and is used to acquire the temperature of the core components of the circuit board and the ambient temperature.

2. The environmentally adaptable TDC+ADC collaborative processing dynamic power laser ranging system according to claim 1, characterized in that, The laser emitting module (01) includes a high-speed low-side gate driver (15), a MOSFET device (16), a pulsed laser diode (17), and a lens (20). The ARM microcontroller (05) controls the switching of the MOSFET device (16) through the high-speed low-side gate driver (15) to drive the pulsed laser diode (17) to emit laser pulses. The variable voltage module (02) includes a digital potentiometer (13) and a DC-DC boost chip (14). Under the adjustment of the digital potentiometer (13), the DC-DC boost chip (14) boosts the input voltage to the laser operating voltage and inputs it to the MOSFET device (16) to provide a stable driving power supply for the pulsed laser diode (17). The lens (20) compresses the light spot and hits the designated target.

3. The environmentally adaptable TDC+ADC collaborative processing dynamic power laser ranging system according to claim 1, characterized in that, The laser receiving module (03) includes a lens (21), a boost circuit (10), an MS7312L module (11), and a CMOS operational amplifier (12). The MS7312L module (11) includes an avalanche photodiode (APD), a transimpedance amplifier (TIA), and a high-speed comparator. The reflected laser spot passes through the target and returns to the laser receiving module (03) via the lens (21). It is received by the avalanche photodiode (APD) on the surface of the MS7312L module (11) and converted into an electrical signal. It is then amplified in two stages by the transimpedance amplifier and the CMOS operational amplifier (12). The boost circuit (10) increases the supply voltage to the reverse bias voltage of the APD to ensure the linearity of the operational amplifier. The amplified signal enters the high-speed ADC acquisition module (19) and synchronously triggers the TDC time measurement module (18) to record the flight time. In both long-distance and short-distance test conditions, the voltage threshold Vth is controlled by the ARM microcontroller (05). The high-speed comparator outputs the compared echo signal based on the value of Vth.

4. The environmentally adaptable TDC+ADC collaborative processing dynamic power laser ranging system according to claim 2, characterized in that, The TDC time measurement and ADC module (04) includes a TDC time measurement module (18) and a high-speed ADC acquisition module (19). The TDC time measurement module (18) is used to measure the laser flight time with high precision, and the high-speed ADC acquisition module (19) is used to sample and analyze the echo signal intensity and waveform output by the laser receiving module at high speed.

5. The environmentally adaptable TDC+ADC collaborative processing dynamic power laser ranging system according to claim 1, characterized in that, The semiconductor cooling module (07) includes a gate driver chip (22), an H-bridge driver circuit (25), an overcurrent protection circuit (26), a semiconductor cooling chip (24), and a heat sink (23). The semiconductor cooling chip adopts a TEC-type device. Combined with the feedback from the low-power temperature acquisition module (09), the ARM microcontroller (05) controls the H-bridge driver circuit (25) through the gate driver chip (22). By controlling the current flow direction of the H-bridge, the current direction of the semiconductor cooling chip (24) is controlled to switch between cooling and heating, so as to maintain the operating temperature of the core device within the set temperature range. The overcurrent protection circuit (26) is used to monitor the current of the semiconductor cooling chip (24), and the heat sink (23) is used to quickly remove the heat from the hot end of the semiconductor cooling chip.

6. The environmentally adaptable TDC+ADC collaborative processing dynamic power laser ranging system according to claim 1, characterized in that, The low-power voltage acquisition module (08) includes a MOSFET device switch (27) and a transistor (28). The ARM microcontroller (05) controls the transistor (28) and drives the MOSFET device switch (27). When the switch is turned off, the standby current is ≤1μA. The low-power temperature acquisition module (09) has the same structure as the low-power voltage acquisition module (08).

7. The environmentally adaptable TDC+ADC collaborative processing dynamic power laser ranging system according to claim 4, characterized in that, The ARM microcontroller (05) controls the digital potentiometer (13) through the PID algorithm to adjust the output voltage of the DC-DC boost chip (14) and dynamically adjust the voltage driving the laser; it receives the time difference data from the TDC time measurement module (18), combines it with the amplitude information of the high-speed ADC acquisition module (19), and uses a combination of dynamic filtering and slope to dynamically compensate for the ranging error under different reflectivities.

8. A control method for an environmentally adaptable dynamic power laser ranging system with TDC+ADC collaborative processing as described in any one of claims 1-7, characterized in that, Includes the following steps: Step 1: System initialization: The ARM microcontroller (05) performs hardware initialization configuration and software parameter setting, including the software initialization of the ARM microcontroller (05) and the TDC time measurement module (18); Step 2: Temperature / Voltage Acquisition: The ARM microcontroller (05) controls the low-power temperature acquisition module (09) to acquire the temperature near the TDC time measurement module (18); the ARM microcontroller (05) controls the low-power voltage acquisition module (08) to acquire the voltage driving the laser emission and the reverse bias voltage of the APD respectively; Step 3: Temperature adjustment: The ARM microcontroller (05) executes temperature control logic based on the temperature information collected by the low-power temperature acquisition module (09), drives the semiconductor cooling / heating and heat dissipation module (07) to work, and adjusts and maintains the temperature of the core components of the system within the preset working range; Step 4: Laser emission power adjustment: Based on the preset target power or according to environmental parameters, drive the power adjustment mechanism of the laser emission module (01) to dynamically adjust the driving laser emission voltage according to the intensity of the collected echo signal and the initial distance, so as to ensure the stability and intensity of the emitted light signal and reduce the power consumption of the system. Step 5: APD voltage adjustment: The reverse bias voltage of the avalanche photodiode (APD) that receives the optical signal is dynamically adjusted according to a preset value or real-time acquired parameters to improve the detection sensitivity and responsivity of the optical signal. Step 6: TDC Data Processing: Receive raw data from the TDC time measurement module (18), which represents the time interval between the laser emission pulse and the received return pulse; perform data processing operations; Step 7: ADC Data Processing: Receive raw data from the high-speed ADC acquisition module (19), which characterizes the intensity of the analog echo signal output by the avalanche photodiode (APD); perform data processing operations; Step 8: Error compensation scheme: Based on the processed TDC time measurement module (18) data, high-speed ADC acquisition module (19) data and real-time acquired temperature / voltage information, execute the error compensation algorithm to calculate and correct the measurement error caused by the difference in reflectivity of the measured object, and generate a more accurate core value of flight time or distance data. Step 9: Output Results: Output the final measurement results after error compensation through a predetermined interface or communication protocol; Step 10: Loop Judgment: After completing the result output step, perform a logical judgment to determine whether the measurement process should continue to a new round of measurement; when the judgment result is "yes", return to step 2 to perform temperature / voltage acquisition and start a new round of measurement loop; when the judgment result is "no", enter the end state.

9. The control method according to claim 8, characterized in that, The data processing flow of the TDC time measurement module includes the following steps: Step 1: System pre-initialization stage: Hardware reset and configuration layer: The ARM microcontroller (05) sends a hardware reset command to the high-speed low-side gate driver (15) and the TDC time measurement module (18); the port function is configured through the ARM microcontroller (05), and the TDC control register parameters are written. Step 2: Pulse sequence emission and raw data acquisition. The high-speed low-side gate driver (15) is triggered by the GPIO interface of the ARM microcontroller (05) to continuously emit Ms groups of laser pulses at fixed time intervals Δt; the output of the TDC time measurement module (18) is captured in real time. Ms The time register (reg) data is grouped, and each group of reg values ​​is the raw quantized value of the flight time of a single laser pulse from emission to reception. Step 3: Data Classification and Outlier Identification: Statistics Ms The frequency of duplicate values ​​in the group reg data; if the frequency of duplicates exceeds a threshold. Ka The system determines that there is out-of-bounds interference; multi-level data cleaning: out-of-bounds situation: location deviation from the median ± Kc Data points are processed by removing all outliers; in the non-out-of-bounds case, the central distribution range of the dataset is preserved; extreme value filtering removes the subset of maximum values ​​from the valid dataset. Ma and minimum subset Mb Eliminate accidental measurement bias; Step 4: Dynamic Filtering and Feature Extraction First-order infinite impulse response (IIR) filtering is applied to the remaining cleaned dataset: y [ n ] =β⋅x [ n ] + ( 1−β ) ⋅y [ n−1 ] (0.1≤ β ≤0.35) in x [ n [ represents the current input value] y [ n−1 [This refers to historical output values.] β Adaptive adjustment to balance noise suppression and response speed; Step 5: Calculate the sliding window mean of the filtering results and output the optimized overall reg value; Step 6: Distance calculation and environmental compensation; Substitute the reg value into the flight time-distance conversion formula and perform temperature drift compensation. By collecting temperature sensor data, the distance value is corrected through a nonlinear correction model. Step 7: Loop control logic; judge the user command or timer flag. If continuous measurement is required, return to step 2 to start a new round of pulse sequence; otherwise, enter sleep mode and turn off the laser drive power supply.

10. The control method according to claim 8, characterized in that, The data processing flow of the ADC module includes the following steps: Step 1: System Initialization Phase Hardware co-booting: Reset the ARM microcontroller (05) and high-speed ADC acquisition module (19), configure the direct memory access channel parameters, and set the sampling depth to [value missing]. Amn A group of continuous waveform storage spaces, in which m × n matrix, m ≥10, n ≥10; Initialize the high-speed comparator threshold voltage Va ( th ), calibrate the trigger timing of the laser emission synchronization signal; Step 2: Waveform Acquisition and Storage: The laser echo signal is acquired at a fixed sampling rate using a high-speed ADC acquisition module (19). Each round of acquisition... Amn Collect the original voltage waveform data; enable DMA double buffering mechanism, and... Amn Data is transmitted to the memory array without loss, avoiding signal distortion caused by interrupt delay of the ARM microcontroller (05); Step 3: Multi-level data cleaning: Peak anomaly removal: Scanning Amn Data matrix, identify and remove two types of outlier subsets: maximum value outliers. Ad The peak value of the waveform exceeds the upper limit of the physical range. Ad Group data distortion anomaly set Ac : Delete the data with the largest / smallest peak values ​​from the remaining data. d Group data and c Suppressing occasional noise interference; Step 4: Waveform Reconstruction and Feature Extraction: After cleaning... A ( mdc ()( ndc The data matrix is ​​averaged point by point to generate a synthesized waveform array with enhanced noise resistance. Step 5: Dynamic error modeling; calculate comparator threshold voltage Va ( th ) and peak voltage Vap slope factor Vk ; Step 6: Distance calculation and output; Vk Substituting these values ​​into a nonlinear error mapping table, which is a discrete table based on actual measurements, we select multiple sets of targets with different reflectivities at different distances through measurements. The slope of the echo waveform at different reflectivities is then obtained through measurement. Vk Index out the corresponding distance compensation amount Sm Output the compensated distance value; Step 7: Loop Control: If the continuous measurement flag is activated, return to Step 2 to start a new round of acquisition; otherwise, turn off the laser power and enter low-power standby mode.

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