Pulse type laser ranging module, method and device and machine readable storage medium

Abstract

The invention provides a pulse type laser ranging module, method and device and a machine readable storage medium. In one example, the pulse type laser ranging module comprises a laser transmitter used for transmitting a laser pulse according to a set laser pulse transmitting parameter; the detector is used for receiving the echo signal and converting the received echo signal into an electric signal; the signal processing unit is used for sampling the electric signal and converting the electric signal into a digital signal; aligning and superposing the digital signals corresponding to the multiple laser pulses, performing peak searching on the superposed digital signals, and determining the highest peak of the superposed digital signals; and under the condition that the extreme value of the highest peak of the superposed digital signals does not exceed a threshold value, at least one parameter in laser pulse emission parameters of the laser emitter is adjusted. According to the scheme provided by the embodiment of the invention, the ranging accuracy can be improved.

Description

Technical Field

[0001] This application relates to the technical field of laser ranging, and particularly to a pulsed laser ranging module, method, device, and machine-readable storage medium. Background Art

[0002] Pulsed laser ranging is a ranging technology based on the principle of laser pulse emission and reflection. Its basic principle is to emit a short pulsed laser towards the target, measure the time from the emission to the return of the laser, and thus calculate the distance to the target. Since the propagation of the laser signal in the atmosphere may be affected by factors such as dust and water vapor in the air, there may be certain errors in pulsed laser ranging.

[0003] How to improve the accuracy of pulsed laser ranging has become a popular research direction. Summary of the Invention

[0004] In view of this, this application provides a pulsed laser ranging module, method, device, and machine-readable storage medium.

[0005] Specifically, this application is implemented through the following technical solutions:

[0006] According to the first aspect of the embodiments of this application, a pulsed laser ranging module is provided, including: a laser emitter, a detector, and a signal processing unit; wherein:

[0007] The laser emitter is configured to emit laser pulses according to the set laser pulse emission parameters; wherein, the laser pulse emission parameters include the emission voltage, pulse width, and the number of pulses; wherein, the number of pulses is greater than 2 times;

[0008] The detector is configured to receive the echo signal and convert the received echo signal into an electrical signal;

[0009] The signal processing unit is configured to sample the electrical signal and convert it into a digital signal; align and superimpose the digital signals corresponding to multiple laser pulses, and perform peak searching on the superimposed digital signal to determine the highest peak of the superimposed digital signal;

[0010] The signal processing unit is further configured to, when the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, adjust at least one of the laser pulse emission parameters of the laser emitter so that the laser emitter emits laser pulses according to the adjusted laser pulse emission parameters; wherein, the adjusted parameter in the laser pulse emission parameters is greater than the corresponding parameter before adjustment;

[0011] The signal processing unit is further configured to perform distance calculation when the extreme value of the highest peak of the superimposed digital signal exceeds the threshold.

[0012] According to a second aspect of the embodiments of the present application, a pulsed laser ranging method is provided, which is applied to a signal processing unit in a pulsed laser ranging module. The pulsed laser ranging module further includes a laser emitter and a detector. The method includes:

[0013] Sampling the electrical signal and converting it into a digital signal; wherein, the electrical signal is obtained by the detector converting the received echo signal, and the echo signal is generated when the laser emitter emits laser pulses according to the set laser pulse emission parameters; the laser pulse emission parameters include the emission voltage, pulse width, and the number of pulses; the number of pulses is greater than 2 times;

[0014] Aligning and superimposing the digital signals corresponding to multiple laser pulses, and performing peak searching on the superimposed digital signal to determine the highest peak of the superimposed digital signal;

[0015] In the case where the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, at least one parameter in the laser pulse emission parameters of the laser emitter is adjusted so that the laser emitter emits laser pulses according to the adjusted laser pulse emission parameters; wherein, the adjusted parameter in the laser pulse emission parameters is greater than the corresponding parameter before adjustment;

[0016] In the case where the extreme value of the highest peak of the superimposed digital signal exceeds the threshold, distance calculation is performed.

[0017] According to a third aspect of the embodiments of the present application, an electronic device is provided, including a processor and a memory. The memory stores machine-executable instructions that can be executed by the processor, and the processor is used to execute the machine-executable instructions to implement the method provided in the second aspect.

[0018] According to a fourth aspect of the embodiments of the present application, a machine-readable storage medium is provided. The machine-readable storage medium stores machine-executable instructions, and when the machine-executable instructions are executed by a processor, the method provided in the second aspect is implemented.

[0019] The technical solution provided by the present application can at least bring the following beneficial effects:

[0020] When the laser emitter emits laser pulses with the set excitation pulse emission parameters, the signal processing unit determines the extreme value of the highest peak of the superimposed digital signal. By comparing the extreme value of the highest peak of the superimposed digital signal with the corresponding threshold, it determines whether the laser power and pulse width of the current laser pulse emission parameters meet the ranging requirements for the current distance. When it is determined that the requirements are not met, the laser pulse emission parameters are adaptively adjusted to increase the ranging range of the pulsed laser ranging module, improve the ranging accuracy, and reduce the ranging power consumption while ensuring the ranging accuracy through the adaptive adjustment of the laser pulse emission parameters. Description of the Drawings

[0021] Figure 1 is a schematic structural diagram of a pulsed laser ranging device shown in an exemplary embodiment of the present application;

[0022] Figure 2 is a schematic diagram of a pulsed laser ranging process shown in an exemplary embodiment of the present application;

[0023] Figure 3 is a schematic diagram of a single echo signal and noise peak shown in an exemplary embodiment of the present application;

[0024] Figure 4 is a schematic flow diagram of a pulsed laser ranging method shown in an exemplary embodiment of the present application;

[0025] Figure 5 is a schematic hardware structure diagram of an electronic device shown in an exemplary embodiment of the present application. Detailed Embodiments

[0026] In order to enable those skilled in the art to better understand the technical solutions provided by the embodiments of the present application and make the above-mentioned objects, features, and advantages of the embodiments of the present application more obvious and understandable, the technical solutions in the embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

[0027] It should be noted that the sequence numbers of the steps in the embodiments of the present application do not indicate the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0028] Please refer to Figure 1 , which is a schematic structural diagram of a pulsed laser ranging module provided by an embodiment of the present application. As Figure 1 shown, the pulsed laser ranging module 100 may include a laser emitter 100, a detector 120, and a signal processing unit 130; where:

[0029] A laser transmitter 110 is configured to emit laser pulses according to the set laser pulse emission parameters. The laser pulse emission parameters include the emission voltage, pulse width, and the number of pulses, where the number of pulses is greater than 2 times.

[0030] A detector 120 is configured to receive the echo signal and convert the received echo signal into an electrical signal.

[0031] A signal processing unit 130 is configured to sample the electrical signal and convert it into a digital signal; align and superimpose the digital signals corresponding to multiple laser pulses, and perform peak searching on the superimposed digital signal to determine the highest peak of the superimposed digital signal.

[0032] The signal processing unit 130 is further configured to, when the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, adjust at least one of the laser pulse emission parameters of the laser transmitter so that the laser transmitter emits laser pulses according to the adjusted laser pulse emission parameters, where the adjusted parameter in the laser pulse emission parameters is greater than the corresponding parameter before adjustment.

[0033] The signal processing unit 130 is further configured to perform distance calculation when the extreme value of the highest peak of the superimposed digital signal exceeds the threshold.

[0034] In the embodiments of the present application, since the loss of laser pulses in the air is different when the flight distances are different, for targets at different distances, the intensities of the echo signals corresponding to single laser pulses sent by the same laser transmitter with the same voltage and pulse width will be different.

[0035] In addition, for a target at the same distance, the higher the emission voltage of the laser pulses emitted by the same laser transmitter, and / or the wider the pulse width of the laser pulses, the higher the intensity of the echo signal usually is.

[0036] When the same laser transmitter sends laser pulses with the same voltage and pulse width, the more consecutive pulses are emitted, the higher the intensity of the superimposed echo signal usually is.

[0037] Based on this, by using a higher emission voltage, a wider pulse width, and / or emitting more pulses, the ranging range covered by the pulsed laser ranging module can be increased, and for targets at a farther distance, the ranging accuracy will be improved.

[0038] However, when the emission voltage is higher and the pulse is wider, the power consumption of the pulsed laser ranging module will be correspondingly higher; the more pulses are emitted, the longer the calculation time during the ranging process of the pulsed laser ranging module will be correspondingly, and the ranging efficiency will be reduced.

[0039] Accordingly, during the process of ranging by the pulsed laser ranging module, the laser emitter can be first controlled to emit laser pulses with relatively low laser pulse emission parameters, and when it is determined that the current laser pulse emission parameters cannot accurately range, the pulse emission parameters can be adaptively adjusted to increase the ranging range of the pulsed laser ranging module.

[0040] Exemplarily, the laser pulse emission parameters can include some or all of the emission voltage, pulse width, and number of pulses.

[0041] Exemplarily, adjusting the laser pulse emission parameters can include, but is not limited to, one or more of the following:

[0042] Increasing the emission voltage, increasing the pulse width of the laser pulse, and increasing the number of pulses (i.e., the number of consecutive laser pulses emitted).

[0043] In the embodiment of the present application, the laser emitter 110 can emit laser pulses according to the set laser pulse emission parameters.

[0044] Exemplarily, the laser emitter 110 can emit laser pulses with a pulse width of the currently required pulse width and a number of pulses of the currently required number of pulses at the currently required emission voltage according to the emission voltage, pulse width, and number of pulses in the current laser pulse emission parameters.

[0045] For example, assuming the emission voltage is V0, the pulse width is PW0, and the number of pulses is n, the laser emitter 110 can emit laser pulses with a pulse width of PW0 continuously n times at the emission voltage V0.

[0046] When the laser pulses emitted by the laser emitter 110 detect a target object, a part of the laser beam will be reflected back by the surface of the target object to form an echo signal.

[0047] The detector 120 can receive the echo signal and convert the received echo signal into an electrical signal.

[0048] The signal processing unit 130 can sample the electrical signal, convert it into a digital signal, and align and superimpose the digital signals corresponding to multiple laser pulses.

[0049] Exemplarily, for the superimposed digital signal, the signal processing unit 130 can perform noise reduction processing on it.

[0050] For example, the signal processing unit 130 can use mean filtering to perform noise reduction processing on the superimposed digital signal and filter the noise in the superimposed digital signal.

[0051] For the superimposed digital signal (which can be after noise reduction processing), the signal processing unit 130 can perform a peak search operation to determine the highest peak of the superimposed digital signal.

[0052] When the highest peak of the superimposed digital signal is determined, the signal processing unit 130 can determine the extreme value of the highest peak.

[0053] For example, the signal processing unit 130 can perform curve fitting based on the sampling point corresponding to the highest peak and the sampling points adjacent to this sampling point, and determine the extreme value of the highest peak based on the curve obtained by fitting.

[0054] Exemplarily, the signal processing unit 130 can compare the extreme value of the determined highest peak with the corresponding threshold.

[0055] Exemplarily, the thresholds corresponding to different laser pulse emission parameters can be different.

[0056] When the signal processing unit 130 determines that the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, it can determine that the laser energy and pulse width corresponding to the current laser pulse emission parameters do not meet the ranging requirements for the current distance. In this case, the signal processing unit 130 can adjust the laser pulse emission parameters of the laser emitter to increase the ranging range of the pulsed laser ranging module.

[0057] Exemplarily, during the process of the signal processing unit 130 adjusting the laser pulse emission parameters of the laser emitter, it can adjust at least one of the laser pulse emission parameters, and the adjusted parameter in the laser pulse emission parameters is greater than the corresponding parameter before adjustment.

[0058] For example, the adjustment of the laser pulse emission parameters can include one or more of the following:

[0059] Increasing the emission voltage, increasing the pulse width of the laser pulse, and increasing the number of pulses.

[0060] Exemplarily, when the signal processing unit 130 has adjusted the laser pulse emission parameters of the laser emitter, it can control the laser emitter 110 to emit laser pulses according to the adjusted laser pulse emission parameters, and the detector 120 receives the echo signal and converts it into an electrical signal.

[0061] The signal processing unit 130 can sample the electrical signal, convert it into a digital signal, and determine the highest peak of the superimposed digital signal again in the above manner, and compare the extreme value of the highest peak of the superimposed digital signal with the corresponding threshold again.

[0062] Exemplarily, in the case where the extreme value of the highest peak of the superimposed digital signal exceeds the corresponding threshold, the signal processing unit 130 may determine that the laser energy and pulse width corresponding to the current laser pulse emission parameters meet the ranging requirements for the current distance. In this case, the signal processing unit 130 may perform distance calculation.

[0063] Exemplarily, the signal processing unit 130 may determine the corresponding flight time (the flight time of the laser pulse in the air) based on the sampling point corresponding to the extreme value of the highest peak of the superimposed digital signal, and determine the distance to the target object based on this flight time.

[0064] Exemplarily, the signal processing unit 130 samples the electrical signal at a fixed interval. Therefore, the sampling points can be converted into time information based on this fixed interval.

[0065] For example, assuming the sampling interval is ΔT, the time corresponding to the first sampling point is ΔT, the time corresponding to the second sampling point is 2*ΔT, and so on.

[0066] It can be seen that in Figure 1 In the shown pulsed laser ranging module, when the laser emitter emits laser pulses through the set excitation pulse emission parameters, the signal processing unit determines the extreme value of the highest peak of the superimposed digital signal. By comparing the extreme value of the highest peak of the superimposed digital signal with the corresponding threshold, it is determined whether the laser power and pulse width of the current laser pulse emission parameters meet the ranging requirements for the current distance. And in the case of determining that the requirements are not met, the laser pulse emission parameters are adaptively adjusted to increase the ranging range of the pulsed laser ranging module, improve the ranging accuracy, and through the adaptive adjustment of the laser pulse emission parameters, while ensuring the ranging accuracy, reduce the ranging power consumption.

[0067] In some embodiments, the laser emitter has multiple different gears, and the laser pulse emission parameters are different for different gears. Each parameter in the high - gear laser pulse parameters is not less than the corresponding parameter in the low - gear laser pulse parameters, and at least one parameter in the high - gear laser pulse parameters is greater than the corresponding parameter in the low - gear laser pulse parameters;

[0068] The signal processing unit 130 is specifically configured to adjust the gear of the laser emitter 110 to a higher gear in the case where the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold and the current gear of the laser emitter 110 is not the highest gear;

[0069] The signal processing unit 130 is specifically configured to determine that the ranging fails in the case where the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold and the current gear of the laser emitter 110 is the highest gear.

[0070] Exemplarily, in order to simplify the operation of adjusting the laser pulse parameters, multiple different gears can be preset for the laser emitter, and different gears correspond to different laser pulse emission parameters.

[0071] Exemplarily, each parameter in the high-gear laser pulse parameters is not less than the corresponding parameter in the low-gear laser pulse parameters, and at least one parameter in the high-gear laser pulse parameters is greater than the corresponding parameter in the low-gear laser pulse parameters.

[0072] In one example, each parameter in the high-gear laser pulse parameters is greater than the corresponding parameter in the low-gear laser pulse parameters.

[0073] Correspondingly, when the signal processing unit 130 determines that the extreme value of the highest peak of the superimposed digital signal does not exceed the corresponding threshold, it can determine whether the current gear of the laser emitter 110 is the highest gear.

[0074] When the current gear of the laser emitter 110 is not the highest gear, the signal processing unit 130 can adjust the gear of the laser emitter 110 to a higher gear.

[0075] In one example, the signal processing unit 130 can gradually increase the gear of the laser emitter 110.

[0076] For example, assume that the gears of the laser emitter 110 include gears 1 to 3, gear 1 is the lowest gear, and gear 3 is the highest gear. When the current gear is gear 1 and the extreme value of the highest peak of the superimposed digital signal does not exceed the corresponding threshold, the signal processing unit 130 can first adjust the gear of the laser emitter 100 to gear 2.

[0077] Exemplarily, when the signal processing unit determines that the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold and the current gear of the laser emitter is the highest gear, it can determine that the ranging fails. For example, output a ranging failure prompt message to prompt relevant personnel that the ranging fails.

[0078] In one example, the laser emitter has 3 gears. Each parameter in the first-gear laser pulse parameters is less than the corresponding parameter in the second-gear laser pulse parameters, and each parameter in the second-gear laser pulse parameters is less than the corresponding parameter in the third-gear laser pulse parameters;

[0079] The signal processing unit 110 is specifically configured to, when the current gear of the laser emitter 110 is the first gear and the extreme value of the highest peak of the superimposed digital signal does not exceed the first threshold, adjust the gear of the laser emitter 110 to the second gear;

[0080] The signal processing unit 110 is further specifically configured to adjust the gear of the laser emitter 110 to the third gear when the current gear of the laser emitter 110 is the second gear and the extreme value of the highest peak of the superimposed digital signal does not exceed the second threshold;

[0081] The signal processing unit is further specifically configured to determine that the ranging fails when the current gear of the laser emitter 110 is the third gear and the extreme value of the highest peak of the superimposed digital signal does not exceed the third threshold.

[0082] Exemplarily, take the laser emitter having 3 gears (from low to high are the first gear, the second gear, and the third gear) as an example.

[0083] Exemplarily, each parameter in the first gear laser pulse parameters is less than the corresponding parameter in the second gear laser pulse parameters, and each parameter in the second gear laser pulse parameters is less than the corresponding parameter in the third gear laser pulse parameters.

[0084] Exemplarily, in the process of comparing the extreme value of the highest peak of the superimposed digital signal with the threshold, different gears correspond to different thresholds.

[0085] Exemplarily, the threshold corresponding to the first gear is the first threshold, the threshold corresponding to the second gear is the second threshold, and the threshold corresponding to the third gear is the third threshold.

[0086] Exemplarily, for any gear, the threshold of this gear is preset or dynamically determined.

[0087] As an example, for any gear, when the threshold of this gear is dynamically determined, it can be determined by the following method:

[0088] Filter the digital signal corresponding to the single echo signal of this gear, and calculate the mean value of the filtering result. Based on this mean value and the number of pulses of this gear, determine the threshold of this gear.

[0089] Exemplarily, for any gear, it is possible to filter the digital signal corresponding to the echo signal of a single laser pulse emitted by the laser emitter in this gear. For example, filter the digital signal by means of mean filtering, and calculate the mean value of the filtering result (that is, calculate the average value of all sampling points of a single pulse), and based on this mean value and the number of pulses of this gear, determine the threshold of this gear.

[0090] For example, the threshold of this gear can be determined by the following method:

[0091] y = x * C + k

[0092] Where y is the threshold, x is the above-mentioned mean value, C is the number of pulses, and k is an empirical value.

[0093] Exemplarily, considering that when the pulsed laser ranging module and the position of the target to be measured remain unchanged, as the number of pulses increases, the effective peak value usually increases accordingly. However, the noise fluctuates and does not increase linearly with the increase in the number of pulses. Therefore, the above method can be used to determine the thresholds for each gear.

[0094] As an example, for any gear, when the threshold for that gear is preset, it can be determined in the following way:

[0095] Based on the threshold weight coefficient of that gear and the number of pulses in that gear, determine the threshold for that gear; wherein, the threshold weight coefficient of that gear is determined based on the test echo signals collected at the limit ranging distance of that gear, and the test echo signals include the echo signals collected for multiple test targets with different reflectivities.

[0096] Exemplarily, for any gear, under the limit ranging distance required to be covered by that gear, echo signals of multiple test targets with different reflectivities (which may include test targets with strong reflectivity and weak reflectivity) can be collected, and based on the collected echo signals, the weight coefficient of the multi-pulse superposition threshold (i.e., the threshold weight coefficient, which can also be called the baseline level) for that gear can be evaluated, and based on the threshold weight coefficient of that gear and the number of pulses in that gear, determine the threshold for that gear.

[0097] For example, the threshold for that gear can be determined in the following way:

[0098] y = D * C

[0099] where y is the threshold, D is the threshold weight coefficient, and C is the number of pulses.

[0100] Exemplarily, in the embodiments of the present application, considering that in the case of a relatively long ranging distance, there are many environmental interference factors and a large impact on the signal-to-noise ratio, therefore, it is necessary to dynamically determine the threshold in real time to improve the ranging accuracy.

[0101] For a relatively short ranging distance, since the interference factors are relatively few, therefore, in order to improve the ranging efficiency, the threshold can be preset.

[0102] For example, for a gear, when the limit ranging distance of that gear exceeds the preset distance threshold, the above threshold can be determined in a dynamic way; when the limit ranging distance of that gear does not exceed the preset distance threshold, the above threshold can be preset.

[0103] In an example, the above first threshold and second threshold are preset, and the third threshold is determined dynamically.

[0104] In some embodiments, the signal processing unit 130 may specifically be configured to determine the search range of the highest peak of the digital signal based on the fixed circuit noise corresponding to the current laser pulse emission parameters, and perform peak searching on the superimposed digital signal within the determined search range to determine the highest peak of the superimposed digital signal.

[0105] Exemplarily, since there are differences in different gear voltage values, fixed circuit noise will be caused, and this fixed noise will change with the changes in the amplitude and pulse width of the pulse. To address this problem, an adaptive filtering algorithm can be used to filter the fixed hardware noise of different gears according to the amplitude of the peak and in combination with the slope, so as to avoid interfering with the target echo signal and affecting the accuracy.

[0106] Exemplarily, the signal processing unit 130 determines the search range of the highest peak of the digital signal based on the fixed circuit noise corresponding to the current laser pulse emission parameters, and performs peak searching on the superimposed digital signal within the determined search range to determine the highest peak of the superimposed digital signal, thereby improving the ranging accuracy.

[0107] In some embodiments, the signal processing unit 130 may specifically be configured to compensate the distance calculation result based on the pre-determined hardware delay compensation value of the pulsed laser ranging module to obtain the final ranging result; wherein, the hardware delay compensation value is determined by means of ranging on the target with the smallest distance for the pulsed laser ranging module.

[0108] Exemplarily, since there will be a certain time difference in the transmission of signals in the hardware circuit, and in addition, due to the slight differences of each pulsed laser ranging module, there are also differences in the delays of the hardware circuits. Therefore, it is necessary to perform separate delay calibration on each pulsed laser ranging module.

[0109] Exemplarily, it can be determined by means of ranging on the target with the smallest distance (the limit close distance, the distance can be approximated as 0) for the pulsed laser ranging module.

[0110] For example, the lens can be shielded so that the laser pulse emitted by the laser emitter is instantaneously reflected back to the receiving circuit (which can be approximated as ranging on a target with a distance of 0, and the time for the laser pulse to fly in the air can be approximated as 0). During this process, the signal processing unit can sample the electrical signal corresponding to the echo signal, calculate the average hardware delay based on multiple groups of sampling data, and this average hardware delay can be used to determine the hardware delay compensation value for compensating the ranging result.

[0111] It should be noted that since the shielding lens can be understood as measuring the distance of an object at the limit close range. At the current distance (the limit is close to 0 meters), the reflectivity of the object is relatively strong, while the usual ADC signal acquisition device only supports the acquisition of values in the range of 0 - 255. Therefore, in the case of using a shielding lens, if a high emission voltage is adopted, the value collected by the ADC will show a truncation phenomenon at 255 (the actual value exceeds the supported range of 0 - 255), that is, the target peak is truncated at an amplitude of 255 and becomes a flat peak. Thus, the position of the peak tip of the target peak cannot be accurately recognized. Therefore, a low emission voltage can be adopted to control the peak tip extreme value of the echo peak below 255, which is convenient for accurately finding the peak tip position.

[0112] Correspondingly, when the signal processing unit calculates the distance in the above manner and obtains the distance calculation result, it can compensate the distance calculation result based on the determined hardware delay compensation value of the pulsed laser ranging module to obtain the final ranging result.

[0113] For example, assuming that the average hardware delay is Δt, the hardware delay compensation value can be v*Δt / 2, where v is the speed of light. Assuming that the distance calculation result obtained by the signal processing unit according to the above method is s, the final ranging result can be s - v*Δt / 2.

[0114] It should be noted that in the embodiment of the present application, during the process of the signal processing unit calculating the distance, when the flight time of the laser pulse in the air is determined (assuming the flight time is t), the flight time can also be compensated based on the average hardware delay to obtain the compensated flight time, and the final ranging distance can be determined based on the compensated flight time.

[0115] For example, the final ranging distance Dis can be:

[0116] Dis = v*(t - Δt) / 2

[0117] Where v is the speed of light.

[0118] To enable those skilled in the art to better understand the technical solutions provided in the embodiments of the present application, the technical solutions provided in the embodiments of the present application will be described below with specific examples.

[0119] In this embodiment, the laser emitter has three different gears (the first gear, the second gear, and the third gear respectively). The laser emission parameters corresponding to the first gear are: emission voltage A1, pulse width B1, and number of pulses C1; the laser emission parameters corresponding to the second gear are: emission voltage A2, pulse width B2, and number of pulses C2; the laser emission parameters corresponding to the third gear are: emission voltage A3, pulse width B3, and number of pulses C3; the thresholds corresponding to the first gear, the second gear, and the third gear are the first threshold (which can be denoted as y1), the second threshold (which can be denoted as y2), and the third threshold (which can be denoted as y3) respectively.

[0120] In this embodiment, the ranging implementation logic is as follows:

[0121] When a ranging instruction is detected, the laser emitter can default to emitting laser pulses in the first gear (corresponding to laser emission voltage A1, pulse width B1, and number of pulses C1).

[0122] The detector can receive the echo signal and convert the echo signal into an electrical signal.

[0123] The signal processing unit samples the echo signal and converts it into a digital signal. The signal processing unit aligns and superimposes the digital signals corresponding to C1 laser pulses and then performs algorithm processing.

[0124] During the algorithm processing, mean filtering can be used to perform noise reduction processing on the superimposed digital signal to filter the noise in the signal. When the noise reduction processing is completed, a peak search operation can be performed to find the highest peak of the superimposed digital signal and compare the extreme value of the highest peak with the first threshold y1.

[0125] Among them, the first threshold y1 can be equal to the product of the baseline level of the first gear (which can be denoted as D1) and C1, that is, y1 = D1 * C1.

[0126] When the extreme value point of the highest peak exceeds the first threshold y1, it indicates that the laser energy and pulse width of the first gear meet the ranging requirements for the current distance, and then subsequent distance calculation is performed.

[0127] When the extreme value of this highest peak does not exceed the first threshold y1, a second-gear laser pulse emission instruction can be triggered, and then the laser emitter is used to re-emit second-gear laser pulses (corresponding to laser emission voltage A2, pulse width B2, and number of pulses C2), and the echo signal is received. The processing flow is the same as the relevant processing of the first gear.

[0128] When the extreme value point of the highest peak in the second gear exceeds the second threshold y2, it indicates that the laser energy and pulse width of the second gear meet the ranging requirements for the current distance, and then subsequent distance calculation is performed.

[0129] Among them, the first threshold y2 can be equal to the product of the second gear baseline level (which can be denoted as D2) and C2, that is, y2 = D2 * C2.

[0130] When the extreme value point of the highest peak in the second gear does not exceed the second threshold y2, a second gear laser pulse emission instruction can be triggered, and then the second gear laser pulse (corresponding to the laser emission voltage A3, pulse width B3, and number of pulses C3) is re-emitted through the laser emitter, and the echo signal is received. The processing flow is the same as the relevant processing in the first gear.

[0131] When the extreme value point of the highest peak in the third gear exceeds the third threshold y3, it indicates that the laser energy and pulse width of this third gear meet the ranging requirements for the current distance, and then subsequent distance calculation is performed.

[0132] When the extreme value point of the highest peak in the third gear does not exceed the third threshold y3, it is determined that the ranging fails, and its schematic diagram can be as Figure 2 shown.

[0133] Exemplarily, the first threshold y1 and the second threshold y2 adopt fixed thresholds, and the third threshold y3 adopts a dynamic threshold.

[0134] The following explains some details.

[0135] 1. Regarding the setting of the first threshold y1 and the second threshold y2:

[0136] Exemplarily, the first threshold and the second threshold can be evaluated and calculated according to the ranging ranges covered by the different emission voltages and pulse widths of the two gears.

[0137] Due to the difference in the reflectivity of different targets, under the same light source and distance, the light intensity reflected by targets with different reflectivities is different, resulting in a difference in the amplitude of the target echo signal peak. Therefore, under the limit ranging distance required for each gear, multiple groups of echo signals of objects with strong and weak reflectivities can be collected, the weight coefficient based on the multi-pulse superposition threshold (the first threshold or the second threshold) in this gear can be evaluated, and then the first threshold or the second threshold can be obtained.

[0138] Exemplarily, the distance ranges required for different gears can have an intersection.

[0139] For example, assume that the distance range covered by the first gear can be from 50m to 250m, and the distance range covered by the second gear can be from 200m to 500m. That is, under normal circumstances, for a target with a distance range of 200m to 500m, the second gear needs to be used for distance measurement. However, the maximum distance that the first gear can measure can also exceed 200m (ideally, the first gear can also accurately measure the distance of targets in the 200 - 250m distance range).

[0140] 2. Calculation method for the third threshold y3:

[0141] In the third gear, the digital signal corresponding to a single laser pulse can be subjected to mean filtering, and then the mean value of the result of the mean filtering is calculated (the average value of all sampling point values of the echo signal of a single laser pulse), denoted as x. The number of pulses in the third gear is C3, then:

[0142] y3 = x * C3 + k

[0143] where k is an empirical value.

[0144] 3. Regarding fixed circuit noise (which can also be called fixed hardware noise):

[0145] Since there are differences in the voltage values of different gears, it will in turn cause fixed circuit noise, and this fixed noise will change with the changes in the amplitude and pulse width of the pulses. To address this issue, an adaptive filtering algorithm can be used to filter the fixed hardware noise of different gears according to the amplitude of the peak, combined with the slope, to avoid interfering with the target echo signal and affecting the accuracy.

[0146] Exemplarily, a schematic diagram of a single echo signal and noise peaks can be as Figure 3 shown. The signal processing unit determines the search range of the highest peak of the digital signal based on the fixed circuit noise corresponding to the current laser pulse emission parameters, and within the determined search range, performs peak searching on the superimposed digital signal to determine the highest peak of the superimposed digital signal, improving the accuracy of distance measurement.

[0147] 4. Regarding hardware delay compensation:

[0148] Since there will be a certain time difference in the transmission of signals in the hardware circuit, in addition, due to the slight differences in each pulsed laser ranging module, there are also differences in the delays of the hardware circuits. Therefore, it is necessary to perform separate delay correction for each pulsed laser ranging module.

[0149] Exemplarily, a low emission voltage combined with a shielded lens can be adopted to enable the laser pulses emitted by the laser emitter to be instantaneously reflected back to the receiving circuit. During this process, the signal processing unit can sample the electrical signal corresponding to the echo signal, calculate the average hardware delay based on multiple sets of sampling data, and this average hardware delay can be used to determine the hardware delay compensation value for compensating the ranging result.

[0150] Please refer to Figure 4 , which is a schematic flowchart of a pulsed laser ranging method provided by an embodiment of the present application. Among them, this pulsed laser ranging method can be applied to the pulsed laser ranging module in the above embodiment, such as the signal processing unit of the pulsed laser module, such as Figure 4 As shown, this pulsed laser ranging method may include the following steps:

[0151] Step S400: Sample the electrical signal and convert it into a digital signal; wherein, this electrical signal is obtained by the detector converting the received echo signal, and this echo signal is the echo signal generated when the laser emitter emits laser pulses according to the set laser pulse emission parameters; the laser pulse emission parameters include the emission voltage, pulse width, and the number of pulses; the number of pulses is greater than 2 times.

[0152] Step S410: Align and superimpose the digital signals corresponding to multiple laser pulses, and perform peak searching on the superimposed digital signal to determine the highest peak of the superimposed digital signal.

[0153] In the embodiment of the present application, since the loss of laser pulses in the air is different when the flight distances are different, for targets at different distances, the intensity of the echo signal corresponding to a single laser pulse sent by the same laser emitter with the same voltage and pulse width will be different.

[0154] In addition, for targets at the same distance, the higher the emission voltage of the laser pulses emitted by the same laser emitter, and / or the wider the pulse width of the laser pulses, the higher the intensity of the echo signal usually is.

[0155] When the same laser emitter sends laser pulses with the same voltage and pulse width, the more consecutive pulses are emitted, the higher the intensity of the superimposed echo signal usually is.

[0156] Based on this, by adopting a higher emission voltage, a wider pulse width, and / or emitting more pulses, the ranging range covered by the pulsed laser ranging module can be increased, and for targets at a farther distance, its ranging accuracy will be improved.

[0157] However, when the emission voltage is higher and the pulse width is wider, the power consumption of the pulsed laser ranging module will be correspondingly higher; the more times the emission pulses are, the longer the calculation time during the ranging process of the pulsed laser ranging module will be, and the ranging efficiency will decrease.

[0158] Accordingly, during the ranging process by the pulsed laser ranging module, the laser emitter can be first controlled to emit laser pulses with relatively low laser pulse emission parameters, and when it is determined that the current laser pulse emission parameters cannot accurately measure the distance, the pulse emission parameters can be adaptively adjusted to increase the ranging range of the pulsed laser ranging module.

[0159] Exemplarily, the laser pulse emission parameters can include some or all of the emission voltage, pulse width, and number of pulses.

[0160] Exemplarily, adjusting the laser pulse emission parameters can include, but is not limited to, one or more of the following:

[0161] Increasing the emission voltage, increasing the pulse width of the laser pulse, and increasing the number of pulses (i.e., the number of consecutive laser pulses emitted).

[0162] In the embodiments of the present application, the laser emitter can emit laser pulses according to the set laser pulse emission parameters.

[0163] Exemplarily, the laser emitter can emit laser pulses with a pulse width of the currently required pulse width for the currently required number of pulses at the currently required emission voltage according to the emission voltage, pulse width, and number of pulses in the current laser pulse emission parameters.

[0164] For example, assuming the emission voltage is V0, the pulse width is PW0, and the number of pulses is n, the laser emitter can emit laser pulses with a pulse width of PW0 continuously n times at the emission voltage V0.

[0165] When the laser pulses emitted by the laser emitter detect a target object, a part of the laser beam will be reflected back from the surface of the target object to form an echo signal.

[0166] The detector can receive the echo signal and convert the received echo signal into an electrical signal.

[0167] The signal processing unit can sample the electrical signal, convert it into a digital signal, and align and superimpose the digital signals corresponding to multiple laser pulses.

[0168] Exemplarily, for the superimposed digital signal, the signal processing unit can perform noise reduction processing on it.

[0169] For example, the signal processing unit can perform noise reduction on the superimposed digital signal by using mean filtering to filter the noise in the superimposed digital signal.

[0170] For the superimposed digital signal (which can be after noise reduction processing), the signal processing unit can perform a peak search operation to determine the highest peak of the superimposed digital signal.

[0171] When the highest peak of the superimposed digital signal is determined, the signal processing unit can determine the extreme value of the highest peak.

[0172] For example, the signal processing unit can perform curve fitting based on the sampling point corresponding to the highest peak and the sampling points adjacent to this sampling point, and determine the extreme value of the highest peak based on the fitted curve.

[0173] Exemplarily, the signal processing unit can compare the extreme value of the determined highest peak with the corresponding threshold.

[0174] Exemplarily, the thresholds corresponding to different laser pulse emission parameters can be different.

[0175] Step S420: When the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, adjust at least one parameter in the laser pulse emission parameters of the laser emitter so that the laser emitter emits laser pulses according to the adjusted laser pulse emission parameters; wherein, the adjusted parameter in the laser pulse emission parameters is greater than the corresponding parameter before adjustment.

[0176] Step S430: When the extreme value of the highest peak of the superimposed digital signal exceeds the threshold, perform distance calculation.

[0177] In the embodiments of the present application, when the signal processing unit determines that the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, it can determine that the laser energy and pulse width corresponding to the current laser pulse emission parameters do not meet the ranging requirements for the current distance. In this case, the signal processing unit can adjust the laser pulse emission parameters of the laser emitter to increase the ranging range of the pulsed laser ranging module.

[0178] Exemplarily, during the process of the signal processing unit adjusting the laser pulse emission parameters of the laser emitter, it can adjust at least one parameter in the laser pulse emission parameters, and the adjusted parameter in the laser pulse emission parameters is greater than the corresponding parameter before adjustment.

[0179] For example, the adjustment of the laser pulse emission parameters can include one or more of the following:

[0180] Increase the emission voltage, increase the pulse width of the laser pulse, and increase the number of pulses.

[0181] Exemplarily, when the signal processing unit adjusts the laser pulse emission parameters of the laser emitter, the laser emitter can be controlled to emit laser pulses according to the adjusted laser pulse emission parameters, and the detector can receive the echo signal and convert it into an electrical signal.

[0182] The signal processing unit can sample the electrical signal, convert the digital signal, and determine the highest peak of the superimposed digital signal again in the above manner, and compare the extreme value of the highest peak of the superimposed digital signal with the corresponding threshold again.

[0183] Exemplarily, when the extreme value of the highest peak of the superimposed digital signal exceeds the corresponding threshold, the signal processing unit can determine that the laser energy and pulse width corresponding to the current laser pulse emission parameters meet the ranging requirements for the current distance. In this case, the signal processing unit can perform distance calculation.

[0184] Exemplarily, the signal processing unit can determine the corresponding flight time (the flight time of the laser pulse in the air) based on the sampling point corresponding to the extreme value of the highest peak of the superimposed digital signal, and determine the distance of the target object based on this flight time.

[0185] In some embodiments, the laser emitter has multiple different gears, and the laser pulse emission parameters are different for different gears. Each parameter in the high - gear laser pulse parameters is not less than the corresponding parameter in the low - gear laser pulse parameters, and at least one parameter in the high - gear laser pulse parameters is greater than the corresponding parameter in the low - gear laser pulse parameters;

[0186] When the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, the adjustment of at least one parameter in the laser pulse emission parameters of the laser emitter may include:

[0187] When the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold and the current gear of the laser emitter is not the highest gear, the gear of the laser emitter is adjusted to a higher gear;

[0188] When the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold and the current gear of the laser emitter is the highest gear, it is determined that the ranging fails.

[0189] Exemplarily, in order to simplify the operation of adjusting the laser pulse parameters, multiple different gears can be set for the laser emitter in advance, and different gears correspond to different laser pulse emission parameters.

[0190] Exemplarily, each parameter in the high - gear laser pulse parameters is not less than the corresponding parameter in the low - gear laser pulse parameters, and at least one parameter in the high - gear laser pulse parameters is greater than the corresponding parameter in the low - gear laser pulse parameters.

[0191] In one example, each parameter in the high - gear laser pulse parameters is greater than the corresponding parameter in the low - gear laser pulse parameters.

[0192] Accordingly, when the signal processing unit determines that the extreme value of the highest peak of the superimposed digital signal does not exceed the corresponding threshold, it can determine whether the current gear of the laser emitter is the highest gear.

[0193] When the current gear of the laser emitter is not the highest gear, the signal processing unit can adjust the gear of the laser emitter to a higher gear.

[0194] Exemplarily, when the signal processing unit determines that the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold and the current gear of the laser emitter is the highest gear, it can determine that the ranging fails. For example, output a ranging failure prompt message to prompt relevant personnel that the ranging fails.

[0195] In some embodiments, the laser emitter has three gears. Each parameter in the first - gear laser pulse parameters is less than the corresponding parameter in the second - gear laser pulse parameters, and each parameter in the second - gear laser pulse parameters is less than the corresponding parameter in the third - gear laser pulse parameters;

[0196] When the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, the adjustment of at least one parameter in the laser pulse emission parameters of the laser emitter may include:

[0197] When the current gear of the laser emitter is the first gear and the extreme value of the highest peak of the superimposed digital signal does not exceed the first threshold, adjust the gear of the laser emitter to the second gear;

[0198] When the current gear of the laser emitter is the second gear and the extreme value of the highest peak of the superimposed digital signal does not exceed the second threshold, adjust the gear of the laser emitter to the third gear;

[0199] When the current gear of the laser emitter is the third gear and the extreme value of the highest peak of the superimposed digital signal does not exceed the third threshold, determine that the ranging fails.

[0200] Exemplarily, take the laser emitter having three gears (from low to high are the first gear, the second gear, and the third gear) as an example.

[0201] Exemplarily, each parameter in the first - gear laser pulse parameters is less than the corresponding parameter in the second - gear laser pulse parameters, and each parameter in the second - gear laser pulse parameters is less than the corresponding parameter in the third - gear laser pulse parameters.

[0202] Exemplarily, during the process of comparing the extreme value of the highest peak of the superimposed digital signal with the threshold, different gears correspond to different thresholds.

[0203] Exemplarily, the threshold corresponding to the first gear is the first threshold, the threshold corresponding to the second gear is the second threshold, and the threshold corresponding to the third gear is the third threshold.

[0204] Exemplarily, for any gear, the threshold of this gear is preset or dynamically determined.

[0205] As an example, for any gear, when the threshold of this gear is dynamically determined, it can be determined in the following way:

[0206] Filter the digital signal corresponding to the single echo signal of this gear, and calculate the average value of the filtered result. Based on this average value and the number of pulses of this gear, determine the threshold of this gear.

[0207] Exemplarily, for any gear, the digital signal corresponding to the echo signal of a single laser pulse emitted by the laser emitter in this gear can be used to filter the digital signal. For example, the digital signal can be filtered by means of average filtering, and the average value of the filtered result (that is, the average value of all sampling points of a single pulse) is calculated. Based on this average value and the number of pulses of this gear, determine the threshold of this gear.

[0208] Exemplarily, considering that when the pulsed laser ranging module and the position of the measured target remain unchanged, as the number of pulses increases, the effective peak value usually increases accordingly. However, the noise is fluctuating and does not increase linearly with the increase in the number of pulses. Therefore, the above method can be used to determine the thresholds of each gear.

[0209] As an example, for any gear, when the threshold of this gear is preset, it can be determined in the following way:

[0210] Based on the threshold weight coefficient of this gear and the number of pulses of this gear, determine the threshold of this gear; wherein, the threshold weight coefficient of this gear is determined based on the test echo signals collected at the limit ranging distance of this gear, and the test echo signals include the echo signals collected for multiple test targets with different reflectivities.

[0211] Exemplarily, for any gear, at the limit ranging distance required to be covered by this gear, echo signals of multiple test targets with different reflectivities (which can include test targets with strong reflectivity and weak reflectivity) can be collected, and based on the collected echo signals, the weight coefficient of the multi-pulse superposition threshold (that is, the threshold weight coefficient) of this gear is evaluated, and based on the threshold weight coefficient of this gear and the number of pulses of this gear, determine the threshold of this gear.

[0212] Exemplarily, in the embodiments of the present application, considering that in the case of a relatively long ranging distance, there are many environmental interference factors and a relatively large impact on the signal-to-noise ratio, it is necessary to dynamically determine the threshold in real time to improve the ranging accuracy.

[0213] For a relatively short ranging distance, since the interference factors are relatively few, in order to improve the ranging efficiency, the threshold can be preset.

[0214] For example, for a gear, when the maximum ranging distance of the gear exceeds the preset distance threshold, the above threshold can be determined dynamically; when the maximum ranging distance of the gear does not exceed the preset distance threshold, the above threshold can be preset.

[0215] In one example, the above first threshold and second threshold are preset, and the third threshold is determined dynamically.

[0216] In some embodiments, the above-mentioned peak searching for the superimposed digital signal to determine the highest peak of the superimposed digital signal may include:

[0217] Determine the search range of the highest peak of the digital signal according to the fixed circuit noise corresponding to the current laser pulse emission parameters, and within the determined search range, perform peak searching on the superimposed digital signal to determine the highest peak of the superimposed digital signal.

[0218] Exemplarily, since there are differences in the voltage values of different gears, which will in turn cause fixed circuit noise, and this fixed noise will change with the amplitude and pulse width of the pulse. To solve this problem, an adaptive filtering algorithm can be used to filter the fixed hardware noise of different gears according to the amplitude of the peak and in combination with the slope, so as to avoid interfering with the target echo signal and affecting the accuracy.

[0219] Exemplarily, the signal processing unit can determine the search range of the highest peak of the digital signal according to the fixed circuit noise corresponding to the current laser pulse emission parameters, and within the determined search range, perform peak searching on the superimposed digital signal to determine the highest peak of the superimposed digital signal, thereby improving the ranging accuracy.

[0220] In some embodiments, the above distance calculation may include:

[0221] Compensate the distance calculation result according to the pre-determined hardware delay compensation value of the pulsed laser ranging module to obtain the final ranging result; wherein, the hardware delay compensation value is determined by the method of ranging for the target with the smallest distance of the pulsed laser ranging module.

[0222] Exemplarily, there is a certain time difference in the transmission of signals in the hardware circuit. In addition, due to the slight differences among individual pulsed laser ranging modules, there are also differences in the delays of the hardware circuits. Therefore, it is necessary to perform separate delay correction for each pulsed laser ranging module.

[0223] Exemplarily, it can be determined by the method of ranging the target with the minimum distance from the pulsed laser ranging module.

[0224] For example, the method of combining a low emission voltage with a shielded lens can be adopted, so that the laser pulse emitted by the laser emitter is instantaneously reflected back to the receiving circuit (which can be approximated as ranging the target with a distance of 0, and the time for the laser pulse to fly in the air can be approximated as 0). During this process, the signal processing unit can sample the electrical signal corresponding to the echo signal, calculate the average hardware delay based on multiple groups of sampling data, and this average hardware delay can be used to determine the hardware delay compensation value for compensating the ranging result.

[0225] Correspondingly, when the signal processing unit calculates the distance calculation result in the above manner, it can compensate the distance calculation result according to the determined hardware delay compensation value of the pulsed laser ranging module to obtain the final ranging result.

[0226] An embodiment of the present application provides an electronic device, including a processor and a memory. Among them, the memory stores machine-executable instructions that can be executed by the processor, and the processor is used to execute the machine-executable instructions to implement the pulsed laser ranging method described above.

[0227] Please refer to Figure 5 , which is a schematic hardware structure diagram of an electronic device provided by an embodiment of the present application. The electronic device may include a processor 501 and a memory 502 storing machine-executable instructions. The processor 501 and the memory 502 can communicate via a system bus 503. And by reading and executing the machine-executable instructions corresponding to the pulsed laser ranging logic in the memory 502, the processor 501 can execute the pulsed laser ranging method described above.

[0228] The memory 502 mentioned herein can be any electronic, magnetic, optical or other physical storage device that can contain or store information such as executable instructions, data, etc. For example, the machine-readable storage medium can be: RAM (Random Access Memory, random access memory), volatile memory, non-volatile memory, flash memory, storage drives (such as hard disk drives), solid-state drives, any type of storage disk (such as optical discs, DVDs, etc.), or similar storage media, or a combination thereof.

[0229] In some embodiments, a storage medium is further provided, such as Figure 5 the memory 502 in [reference], which is a machine-readable storage medium. Machine-executable instructions are stored in the storage medium, and when the machine-executable instructions are executed by a processor, the pulsed laser ranging method described above is implemented. For example, the storage medium may be a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

Claims

1. A pulsed laser ranging module, characterized in that: include: Laser emitter, detector and signal processing unit; wherein: A laser transmitter, used to transmit laser pulses according to the set laser pulse transmission parameters; wherein the laser pulse transmission parameters include transmission voltage, pulse width, and pulse number; wherein the pulse number is greater than 2 times; A detector, used for receiving the echo signal and converting the received echo signal into an electrical signal; A signal processing unit is used to sample the electrical signal and convert it into a digital signal; align and superimpose the digital signals corresponding to multiple laser pulses, and perform peak search on the superimposed digital signal to determine the highest peak of the superimposed digital signal; The signal processing unit is further used to adjust at least one parameter of the laser pulse emission parameters of the laser emitter when the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold value, so that the laser emitter emits laser pulses according to the adjusted laser pulse emission parameters; wherein the adjusted parameter of the laser pulse emission parameters is greater than the corresponding parameter before adjustment; The signal processing unit is further used to perform distance calculation when the extreme value of the highest peak of the superimposed digital signal exceeds a threshold.

2. The pulse laser ranging module according to claim 1, characterized in that: The laser transmitter has a plurality of different gears, and the laser pulse emission parameters of different gears are different, each parameter of the high-gear laser pulse parameters is not less than the corresponding parameter of the low-gear laser pulse parameters, and at least one parameter of the high-gear laser pulse parameters is greater than the corresponding parameter of the low-gear laser pulse parameters; The signal processing unit is specifically used to adjust the gear of the laser transmitter to a higher gear when the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold and the current gear of the laser transmitter is not the highest gear; The signal processing unit is specifically used to determine that the ranging fails when the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold and the current gear position of the laser transmitter is the highest gear position.

3. The pulse laser ranging module according to claim 2, characterized in that: The laser transmitter has three gears, each parameter in the laser pulse parameter of the first gear is smaller than the corresponding parameter in the laser pulse parameter of the second gear, and each parameter in the laser pulse parameter of the second gear is smaller than the corresponding parameter in the laser pulse parameter of the third gear; The signal processing unit is specifically configured to adjust the gear of the laser transmitter to the second gear when the current gear of the laser transmitter is the first gear and the extreme value of the highest peak of the superimposed digital signal does not exceed the first threshold; The signal processing unit is further specifically configured to adjust the gear of the laser transmitter to a third gear when the current gear of the laser transmitter is the second gear and the extreme value of the highest peak of the superimposed digital signal does not exceed the second threshold; The signal processing unit is further specifically used to determine that the ranging fails when the current gear position of the laser transmitter is the third gear position and the extreme value of the highest peak of the superimposed digital signal does not exceed the third threshold.

4. The pulsed laser ranging module according to claim 2 or 3, characterized in that: For any gear, the threshold value of the gear is preset or dynamically determined.

5. The pulse laser ranging module according to claim 4, characterized in that: For any gear, when the threshold of the gear is dynamically determined, it is determined in the following way: Filter the digital signal corresponding to the single echo signal of the gear position, and average the filtering results, and determine the threshold value of the gear position based on the average value and the number of pulses of the gear position; and / or, For any gear, when the threshold value of the gear is preset, it is determined in the following way: The threshold of the gear position is determined according to the threshold weight coefficient of the gear position and the number of pulses of the gear position; wherein the threshold weight coefficient of the gear position is determined based on the test echo signal collected at the extreme ranging distance of the gear position, and the test echo signal includes echo signals collected for test targets with multiple different reflectivities.

6. The pulse laser ranging module according to claim 3, characterized in that: The first threshold and the second threshold are preset, and the third threshold is dynamically determined.

7. The pulse laser ranging module according to claim 1, characterized in that: The signal processing unit is specifically used to determine the search range of the highest peak of the digital signal based on the fixed circuit noise corresponding to the current laser pulse emission parameters, and to search for the peak of the superimposed digital signal within the determined search range to determine the highest peak of the superimposed digital signal.

8. The pulse laser ranging module according to claim 1, characterized in that: The signal processing unit is specifically used to compensate the distance calculation result according to the predetermined hardware delay compensation value of the pulse laser ranging module to obtain the final ranging result; wherein the hardware delay compensation value is determined by measuring the distance of the target with the shortest distance from the pulse laser ranging module.

9. A pulsed laser ranging method, characterized in that: A signal processing unit applied to a pulsed laser ranging module, wherein the pulsed laser ranging module further comprises a laser emitter and a detector, wherein the method comprises: Sampling the electrical signal and converting it into a digital signal; wherein the electrical signal is obtained by converting the received echo signal by the detector, and the echo signal is an echo signal generated when the laser transmitter emits a laser pulse according to the set laser pulse emission parameters; the laser pulse emission parameters include emission voltage, pulse width, and pulse number; the pulse number is greater than 2 times; Aligning and superimposing the digital signals corresponding to the multiple laser pulses, and performing peak searching on the superimposed digital signals to determine the highest peak of the superimposed digital signals; When the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold value, at least one parameter of the laser pulse emission parameters of the laser emitter is adjusted so that the laser emitter emits laser pulses according to the adjusted laser pulse emission parameters; wherein the adjusted parameter of the laser pulse emission parameters is greater than the corresponding parameter before adjustment; When the extreme value of the highest peak of the superimposed digital signal exceeds the threshold value, the distance calculation is performed.

10. The method according to claim 9, characterized in that The laser transmitter has a plurality of different gears, and the laser pulse emission parameters of different gears are different, each parameter of the high-gear laser pulse parameters is not less than the corresponding parameter of the low-gear laser pulse parameters, and at least one parameter of the high-gear laser pulse parameters is greater than the corresponding parameter of the low-gear laser pulse parameters; When the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, adjusting at least one parameter of the laser pulse emission parameters of the laser emitter includes: When the maximum peak value of the superimposed digital signal does not exceed the threshold value and the current gear position of the laser transmitter is not the highest gear position, adjusting the gear position of the laser transmitter to a higher gear position; When the maximum peak value of the superimposed digital signal does not exceed the threshold value and the current gear position of the laser transmitter is the highest gear position, it is determined that the ranging fails; The laser transmitter has three gears, each parameter in the laser pulse parameter of the first gear is smaller than the corresponding parameter in the laser pulse parameter of the second gear, and each parameter in the laser pulse parameter of the second gear is smaller than the corresponding parameter in the laser pulse parameter of the third gear; When the extreme value of the highest peak of the superimposed digital signal does not exceed the threshold, adjusting at least one parameter of the laser pulse emission parameters of the laser emitter includes: When the current gear position of the laser transmitter is the first gear position and the extreme value of the highest peak of the superimposed digital signal does not exceed the first threshold value, adjusting the gear position of the laser transmitter to the second gear position; When the current gear position of the laser transmitter is the second gear position and the extreme value of the highest peak of the superimposed digital signal does not exceed the second threshold value, adjusting the gear position of the laser transmitter to the third gear position; When the current gear position of the laser transmitter is the third gear position and the extreme value of the highest peak of the superimposed digital signal does not exceed the third threshold value, determining that the ranging fails; Wherein, for any gear, the threshold value of the gear is preset, or dynamically determined; Wherein, for any gear, when the threshold value of the gear is dynamically determined, it is determined in the following manner: Filter the digital signal corresponding to the single echo signal of the gear position, and average the filtering results, and determine the threshold value of the gear position based on the average value and the number of pulses of the gear position; and / or, For any gear, when the threshold value of the gear is preset, it is determined in the following way: Determine the threshold value of the gear position according to the threshold weight coefficient of the gear position and the number of pulses of the gear position; wherein the threshold weight coefficient of the gear position is determined based on the test echo signal collected at the extreme ranging distance of the gear position, and the test echo signal includes echo signals collected for multiple test targets with different reflectivities; Wherein, the first threshold and the second threshold are preset, and the third threshold is determined dynamically; The step of searching for peaks on the superimposed digital signals to determine the highest peak of the superimposed digital signals includes: Determine the search range of the highest peak of the digital signal according to the fixed circuit noise corresponding to the current laser pulse emission parameters, and search for the peak of the superimposed digital signal within the determined search range to determine the highest peak of the superimposed digital signal; The distance calculation includes: According to the predetermined hardware delay compensation value of the pulse laser ranging module, the distance calculation result is compensated to obtain the final ranging result; wherein the hardware delay compensation value is determined by measuring the distance of the target with the shortest distance from the pulse laser ranging module.

11. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores machine executable instructions that can be executed by the processor, and the processor is used to execute the machine executable instructions to implement the method according to claim 9 or 10.

12. A machine-readable storage medium, characterized in that: The machine-readable storage medium stores machine-executable instructions, and when the machine-executable instructions are executed by a processor, the method according to claim 9 or 10 is implemented.

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