Laser radar and dynamic adjustment system and method thereof

Abstract

A kind of dynamic adjustment system for laser radar, the laser radar includes multiple light emitting devices, the multiple light emitting devices emit light under the control of first voltage, and stop emitting light under the control of second voltage;The dynamic adjustment system includes: temperature monitoring unit for obtaining ambient temperature;Control unit is used to adjust the voltage value of the first voltage and / or the second voltage according to the ambient temperature, to adjust the working state of the light emitting device.The technical scheme of the present application can ensure that the light emitting device maintains the consistency of emission power when the ambient temperature changes, thereby ensuring the ranging accuracy of laser radar;In addition, the voltage value of the first voltage and the second voltage can also be adjusted synchronously, so as to reduce the difference between the first voltage and the second voltage without affecting the normal operation of the light emitting device, thereby reducing the energy loss of laser radar.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of laser radar, in particular to a laser radar and a dynamic adjustment system and method thereof. BACKGROUND

[0002] The driving circuit of the light emitting device is generally composed of a laser, an energy storage capacitor, and a high-speed switch (such as GaN). In order to further improve the integration, the driving circuit can expand the number of high-speed switches through a multiplexer (MUX), so as to drive multiple high-speed switches in time.

[0003] With the increase of the power density of the light emitting device, the integration of the driving circuit cannot be improved to a satisfactory degree. Therefore, in this case, a driving scheme based on a voltage bus (HVBUS) is proposed. The scheme can increase the number of voltage buses of the light emitting device, and control the light emitting device to emit light by controlling the voltage of the voltage bus. When the voltage of the voltage bus decreases below the light emitting threshold of the light emitting device, the light emitting device will not emit light regardless of whether the high-speed switch is on or not. As shown in the driving circuit, Figure 1 In the driving circuit, 4 voltage buses A-D (i.e. HV_BUS_A-HV_BUS_D) share 1 power supply HV, and each light emitting device is driven in a 4-way common cathode mode, that is, the common cathodes of the 4 light emitting devices are connected to 1 high-speed switch, the anodes of the 4 light emitting devices are respectively connected to 4 voltage buses A-D, and each voltage bus is connected with a resistor R and a capacitor C.

[0004] The driving scheme based on the voltage bus also has problems, such as in order to ensure that the bus voltage does not appear too large pressure drop when the light emitting device emits light, it is often necessary to increase the energy storage capacitor on the voltage bus, but the existence of the energy storage capacitor will also cause the voltage of the voltage bus to be unable to quickly decrease below the light emitting threshold of the light emitting device. Therefore, a low voltage is added on the basis of the high voltage, i.e. HV_H and HV_L in Figure 2 HV_H is used to control the light emitting device to emit light, and HV_L is used to rapidly discharge the voltage of the voltage buses A-D to below the light emitting threshold of the light emitting device.

[0005] However, the change of the ambient temperature will cause the change of the light emitting power and energy loss of the light emitting device, such as when the laser radar measures the distance, the high voltage HV_H of the light emitting device changes with the temperature, causing the light emitting power to be inconsistent, thereby causing the distance measuring accuracy to be inconsistent; or the low voltage HV_L of the light emitting device changes with the temperature, causing the energy loss of the light emitting device to increase. SUMMARY

[0006] The application provides a laser radar, a dynamic adjustment system and a dynamic adjustment method thereof, which can ensure that the light emitting device maintains the consistency of the emission power when the ambient temperature changes, thereby ensuring the ranging accuracy of the laser radar.

[0007] To solve the above technical problems, in a first aspect, the embodiments of the application provide a dynamic adjustment system for a laser radar, the laser radar comprising a plurality of light emitting devices, the plurality of light emitting devices emitting light under the control of a first voltage and stopping emitting light under the control of a second voltage, the dynamic adjustment system for the laser radar comprising: a temperature monitoring unit configured to acquire an ambient temperature; and a control unit configured to adjust a voltage value of the first voltage and / or the second voltage according to the ambient temperature, so as to adjust a working state of the light emitting device.

[0008] Optionally, the control unit synchronously adjusts the first voltage and the second voltage according to the ambient temperature when the ambient temperature reaches a preset threshold.

[0009] Optionally, the control unit is configured to adjust the voltage value of the first voltage according to the ambient temperature, so that the light emitting device maintains the same emission power.

[0010] Optionally, the control unit is configured to adjust the voltage value of the second voltage according to the ambient temperature, so that the difference between the voltage value of the adjusted second voltage and the voltage value of the first voltage is minimized.

[0011] Optionally, the control unit acquires the voltage value of the first voltage and / or the second voltage according to the corresponding relationship between the first voltage and / or the second voltage and the ambient temperature.

[0012] Optionally, the control unit outputs a pulse signal with different duty cycles, so as to adjust the voltage value of the first voltage and / or the second voltage.

[0013] Optionally, the dynamic adjustment system further comprises a feedback unit configured to acquire the voltage value of the adjusted first voltage and / or the second voltage.

[0014] Optionally, the control unit outputs a pulse signal, and the control unit adjusts the duty cycle of the pulse signal according to the voltage value fed back by the feedback unit, so as to adjust the voltage value of the first voltage and / or the second voltage.

[0015] Optionally, the dynamic adjustment system further comprises a power supply module configured to provide the first voltage and the second voltage, so as to control whether the light emitting device emits light.

[0016] Optionally, the power module comprises a first power module and a second power module; the first power module is configured to provide the first voltage for controlling the light emitting device to emit light; and the second power module is configured to provide the second voltage for controlling the light emitting device to stop emitting light.

[0017] Optionally, the second power module comprises a filtering unit configured to filter the pulse signal output by the control unit and output a filtered voltage to a first control unit; and the first control unit is configured to provide the second voltage according to the filtered voltage.

[0018] Optionally, the second power module comprises a converting unit configured to convert the pulse signal output by the control unit into a converted signal having a reference voltage; and a filtering unit configured to filter the converted signal output by the converting unit and output a filtered voltage to a first control unit; and the first control unit is configured to provide the second voltage according to the filtered voltage.

[0019] Optionally, the converting unit comprises a gating unit, a first input terminal of the gating unit being grounded, a second input terminal of the gating unit being connected to the reference voltage, and an output terminal of the gating unit outputting the converted signal.

[0020] Optionally, the first power module comprises a second control unit configured to provide the first voltage; and a control terminal of the second control unit being connected to the pulse signal input by the control unit.

[0021] Optionally, the dynamic adjustment system further comprises a plurality of voltage buses, each light emitting device being connected to the power module through one of the voltage buses; and at least one switching device, the light emitting devices not connected to the same voltage bus being connected to one of the switching devices, and the switching device being configured to controllably connect or disconnect the light emitting devices connected to the same voltage bus.

[0022] Optionally, the power module outputs the first voltage to the voltage buses and controls the light emitting devices connected to the voltage buses to be turned on through the switching device, so as to control the light emitting devices to emit light.

[0023] In a second aspect, the embodiments of the present application further disclose a dynamic adjustment method for a laser radar, the laser radar comprising a plurality of light emitting devices, the plurality of light emitting devices emitting light under the control of a first voltage, and the light emitting devices stopping emitting light under the control of a second voltage; and the dynamic adjustment method comprising: acquiring an ambient temperature; and adjusting a voltage value of the first voltage and / or the second voltage according to the ambient temperature, so as to adjust a working state of the light emitting devices.

[0024] Optionally, the adjusting the voltage value of the first voltage and / or the second voltage according to the ambient temperature comprises: adjusting the voltage value of the first voltage according to the ambient temperature, so that the light emitting device keeps the light emitting power unchanged; and / or adjusting the voltage value of the second voltage according to the ambient temperature, so that the difference between the voltage value of the adjusted second voltage and the voltage value of the first voltage is minimized.

[0025] Optionally, the adjusting the voltage value of the first voltage and / or the second voltage according to the ambient temperature comprises: adjusting the voltage value of the first voltage according to the ambient temperature, so that the light emitting device keeps the light emitting power unchanged; and / or adjusting the voltage value of the second voltage according to the ambient temperature, so that the difference between the voltage value of the adjusted second voltage and the voltage value of the first voltage is minimized.

[0026] In a third aspect, the embodiment of the present application further discloses a laser radar, which comprises a light emitting device for emitting a detection light beam, the light emitting device emits light under the control of a first voltage and stops emitting light under the control of a second voltage; a light receiving device for receiving a return light beam reflected by an obstacle; and the dynamic adjustment system.

[0027] Compared with the prior art, the technical scheme of the embodiment of the present application has the following beneficial effects:

[0028] In the technical scheme of the present application, the ambient temperature of the laser radar is monitored and acquired by the temperature monitoring unit, and the voltage value of the first voltage and / or the second voltage is adjusted based on the ambient temperature by the control unit. On the one hand, by adjusting the first voltage, the light emitting device can keep the emission power consistent when the ambient temperature changes, thereby ensuring the ranging accuracy of the laser radar. On the other hand, by synchronously adjusting the voltage values of the first voltage and the second voltage, the difference between the first voltage and the second voltage can be reduced without affecting the normal operation of the light emitting device, thereby reducing the energy loss of the laser radar. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a schematic diagram of a driving circuit structure based on a voltage bus in the prior art;

[0030] Figure 2 is a schematic diagram of another driving circuit structure based on a voltage bus in the prior art;

[0031] Figure 3 is a structural schematic diagram of a dynamic adjustment system provided by the embodiment of the present application;

[0032] Figure 4 is a schematic diagram of a voltage and temperature change relationship in the embodiment of the present application;

[0033] Figure 5 is a structural schematic diagram of another dynamic adjustment system provided by the embodiment of the present application;

[0034] Figure 6 is a flow chart of a dynamic adjustment method provided by an embodiment of the present application;

[0035] Figure 7 is a structural schematic diagram of a driving circuit provided by an embodiment of the present application;

[0036] Figure 8 is a structural schematic diagram of a second power module provided by an embodiment of the present application;

[0037] Figure 9 is a structural schematic diagram of a first power module provided by an embodiment of the present application;

[0038] Figure 10 is a partial structural schematic diagram of a first power module provided by an embodiment of the present application. DETAILED DESCRIPTION

[0039] As described in the background, the change of ambient temperature will cause the change of light emitting power and energy loss of the light emitting device. For example, when the laser ranging, the high voltage HV_H of the light emitting device changes with the temperature, which causes the inconsistency of light emitting power, thereby causing the inconsistency of ranging accuracy; or the low voltage HV_L of the light emitting device changes with the temperature, which causes the increase of energy loss of the light emitting device.

[0040] In the technical solution of the present application, the ambient temperature of the laser radar is monitored and acquired by the temperature monitoring unit, and the voltage value of the first voltage and / or the second voltage is adjusted based on the ambient temperature by the control unit. On the one hand, by adjusting the first voltage, the light emitting device can maintain the consistency of the emission power when the ambient temperature changes, thereby ensuring the ranging accuracy of the laser radar; on the other hand, by synchronously adjusting the voltage values of the first voltage and the second voltage, the difference between the first voltage and the second voltage can be reduced without affecting the normal operation of the light emitting device, thereby reducing the energy loss of the laser radar.

[0041] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0042] Figure 3 is a structural schematic diagram of a dynamic adjustment system provided by an embodiment of the present application.

[0043] Figure 3The dynamic adjustment system 30 shown can be used in a laser radar. The laser radar includes multiple light emitting devices 50. The multiple light emitting devices 50 emit light under the control of a first voltage and stop emitting light under the control of a second voltage. At the same temperature, the voltage value of the first voltage is greater than the voltage value of the second voltage; and the minimum value of the voltage range of the first voltage is greater than the maximum value of the voltage range of the second voltage.

[0044] It should be noted that the light emitting device 50 can be a vertical-cavity surface-emitting laser (VCSEL) or any other feasible type of light emitting device, and the embodiment of the present invention does not limit this.

[0045] like Figure 3 As shown, the dynamic adjustment system 30 may include a temperature monitoring unit 301 and a control unit 302 .

[0046] The temperature monitoring unit 301 is used to obtain the ambient temperature; the control unit 302 is used to adjust the voltage value of the first voltage and / or the second voltage according to the ambient temperature to adjust the working state of the light emitting device 50.

[0047] In a specific implementation, the ambient temperature acquired by the temperature monitoring unit 301 refers to the temperature around the laser radar, which can be the ambient temperature outside the laser radar or the ambient temperature inside the laser radar. The ambient temperature value is usually in the range of -40-85°C.

[0048] Specifically, the temperature monitoring unit 301 may be a thermistor, such as a positive temperature coefficient thermistor (PTC) and a negative temperature coefficient thermistor (NTC), or any other feasible device capable of measuring temperature.

[0049] In a specific implementation, the control unit 302 adjusts the voltage value of the first voltage and / or the second voltage by controlling the power module 40. The power module 40 provides the first voltage and the second voltage to control whether the light emitting device 50 emits light. The control unit 302 can adjust only the voltage value of the first voltage, only the voltage value of the second voltage, or simultaneously adjust the voltage values ​​of the first voltage and the second voltage.

[0050] In the embodiment, the dynamic adjustment system 30 adjusts the first voltage according to the temperature change, so that the light emitting device can maintain the emission power consistency when the ambient temperature changes, i.e., at different ambient temperatures (for example, in the range of -40-85℃), thereby ensuring the ranging accuracy of the lidar. Further, the control unit 302 synchronously adjusts the first voltage and the second voltage according to the ambient temperature, which can reduce the difference between the first voltage and the second voltage at the same ambient temperature without affecting the normal operation of the light emitting device, thereby reducing the energy loss of the lidar.

[0051] In a specific embodiment, the light emitting device 50 (for example, a VCSEL) has different light emission powers when controlled by the same voltage (for example, 17-20V) at different temperatures. Referring to Figure 4 , curve 401 is a schematic curve of the change of the first voltage required to control the light emitting device to maintain the same light emission power at different temperatures. In order to maintain the light emission power of the light emitting device 50 unchanged at different ambient temperatures, when the ambient temperature reaches a preset threshold, for example, when the ambient temperature is lower than 40 degrees, the voltage value of the first voltage is increased according to curve 401; and when the ambient temperature does not reach the preset threshold, for example, when the ambient temperature is higher than 40 degrees, the voltage value of the first voltage is not adjusted.

[0052] In addition, energy loss occurs in the process of controlling the light emitting device 50 from being turned on to being turned off. Referring to Figure 2 , when the voltage bus A-D switches the voltage, i.e., when the voltage bus voltage is switched from the first voltage HV_H to the second voltage HV_L, the bus capacitances C1-C4 will be discharged rapidly, causing energy loss, and the calculation formula is 0.5f pulse ×C×ΔV 2 , where f pulse is the light emission frequency of the light emitting device 50, and ΔV is the voltage difference between the first voltage HV_H and the second voltage HV_L. The energy loss during discharging is mainly related to the square of the voltage difference ΔV 2 . In order to reduce the discharge loss, the voltage difference between the first voltage and the second voltage can be reduced as much as possible under the condition of ensuring the normal turn-off of the light emitting device (i.e., ensuring that the light emitting device does not emit light). Specifically, referring to Figure 4 , curve 402 is a schematic curve of the change of the second voltage required to control the light emitting device to be turned off at different temperatures. When the ambient temperature reaches a preset threshold, for example, when the ambient temperature is lower than 40 degrees, the voltage value of the second voltage can be adjusted according to curve 402 to reduce the discharge loss as much as possible under the condition of ensuring that the light emitting device 50 does not emit light, i.e., to reduce the voltage difference ΔV of the light emitting device 50 at the same ambient temperature while ensuring that it does not emit light. When the ambient temperature does not reach the preset threshold, for example, when the ambient temperature is higher than 40 degrees, the voltage value of the second voltage is not adjusted.

[0053] In another specific embodiment, the control unit 302 can obtain the voltage value of the first voltage and / or the second voltage according to the correspondence between the first voltage and / or the second voltage and the ambient temperature.

[0054] In this embodiment, the correspondence between the first voltage and the ambient temperature can be obtained by measuring the light emitting device 50 in advance, and the correspondence between the first voltage and the ambient temperature can refer to the curve 401 shown in FIG. 4A in detail. Figure 4 The correspondence between the second voltage and the ambient temperature can also be obtained by measuring the light emitting device 50 in advance, and the correspondence between the second voltage and the ambient temperature can refer to the curve 402 shown in FIG. 4B in detail. The correspondence between the first voltage and the ambient temperature and the correspondence between the second voltage and the ambient temperature are stored in the memory in advance, and the control unit 302 can directly call the above-mentioned correspondence when adjusting the first voltage and / or the second voltage. Figure 4

[0055] In a specific implementation, the control unit 302 can determine the target on voltage value required for controlling the light emitting device 50 to maintain the current emission power to emit light at the current ambient temperature according to the curve 401 or the correspondence between the first voltage and the ambient temperature, and adjust the voltage value of the first voltage for controlling the light emitting device 50 to emit light to the target on voltage value.

[0056] Correspondingly, the control unit 302 can determine the target off voltage value required for controlling the light emitting device 50 to stop emitting light at the current ambient temperature according to the curve 402 or the correspondence between the second voltage and the ambient temperature, and adjust the voltage value of the second voltage for controlling the light emitting device 50 to stop emitting light to the target off voltage value, and the difference between the target off voltage value and the voltage value of the first voltage is minimum.

[0057] It can be understood that the correspondence between the first voltage and / or the second voltage and the ambient temperature of different types of light emitting devices can be different, and the embodiments of the present application do not limit this.

[0058] It should be noted that the first voltage for controlling the light emitting device to emit light has a voltage range, Figure 4 The curve 401 shown in FIG. 4A refers to a variation curve of the minimum value of the first voltage at different temperatures, and the curve 402 refers to a variation curve of the maximum value of the second voltage at different temperatures.

[0059] In one non-limiting embodiment, the control unit 302 outputs pulse signals with different duty cycles for adjusting the voltage value of the first voltage and / or the second voltage.

[0060] ​In this embodiment, pulse signals with different duty cycles can control the power module 40 to generate different voltage values ​​of the first voltage and / or the second voltage.

[0061] In a non-limiting embodiment, the dynamic adjustment system 30 may further include a feedback unit for obtaining the adjusted voltage value of the first voltage and / or the second voltage. Furthermore, the control unit 302 outputs a pulse signal, and the control unit 302 adjusts the duty cycle of the pulse signal based on the voltage value fed back by the feedback unit to continue adjusting the voltage value of the first voltage and / or the second voltage.

[0062] In a specific embodiment, the hardware adjustment interface of the first voltage and the second voltage are independent and can be implemented by a field programmable gate array (FPGA) (i.e. Figure 5 The control unit 501) shown controls and adjusts the voltage value of the first voltage and / or the second voltage.

[0063] For details, please refer to Figure 5 The power supply module includes a first power supply module 503 and a second power supply module 504. The first power supply module 503 can provide a first voltage HV_H, and the second power supply module 504 can provide a second voltage HV_L. The temperature monitoring unit 502 can monitor the external temperature of the lidar in real time. When the preset threshold is reached, the control unit 501 outputs a pulse width modulation (PWM) signal to the first power supply module 503 to adjust the voltage value of the first voltage HV_H. Synchronously, the control unit 501 outputs a PWM signal to the second power supply module 504 to adjust the voltage value of the second voltage HV_L.

[0064] The control unit 501 may also include a built-in analog-to-digital converter (ADC) to monitor the voltage values ​​of the first voltage HV_H and the second voltage HV_L. The first input of the ADC is connected to the first voltage HV_H, the second input is connected to the second voltage HV_L, and the output of the ADC is coupled to the control unit 501. The control unit 501 obtains an error through a readback check based on the voltage values ​​of the first voltage HV_H and the second voltage HV_L fed back by the ADC, and continues to adjust the voltage values ​​of the first voltage HV_H and the second voltage HV_L based on the error until the voltage values ​​of the first voltage HV_H and the second voltage HV_L reach the target values.

[0065] In another specific implementation, the ADC may also be external to the control unit 501 .

[0066] The dynamic adjustment system shown in the embodiments of the present application can realize flexible adjustment range, and the hardware peripheral circuit is simple and easy to implement.

[0067] In specific implementation, the dynamic adjustment system can correspond to a chip with a dynamic adjustment function in a laser radar or a terminal device, such as a SOC (System-On-a-Chip), a baseband chip, etc.; or correspond to a chip module including a chip with a dynamic adjustment function in the laser radar or the terminal device; or correspond to a chip module with a data processing function, or correspond to the laser radar or the terminal device.

[0068] In one non-limiting embodiment, Figure 6 A flowchart of a dynamic adjustment method is shown.

[0069] Specifically, the dynamic adjustment method can include the following steps:

[0070] Step 601: Obtain the ambient temperature.

[0071] Step 602: Determine whether the ambient temperature reaches a preset threshold value. If yes, execute step 603, otherwise continue to execute step 601.

[0072] Step 603: Determine the target on-voltage of the first voltage and / or the target off-voltage of the second voltage according to the ambient temperature. Specifically, in the case where the ambient temperature is known, the target on-voltage can be determined by looking up the corresponding relationship or curve 401 between the ambient temperature and the first voltage; and the target off-voltage can be determined by looking up the corresponding relationship or curve 402 between the ambient temperature and the second voltage.

[0073] Step 604: Adjust the voltage value of the first voltage and / or the second voltage. Specifically, the voltage value of the first voltage can be adjusted to the voltage value of the target on-voltage, and the voltage value of the second voltage can be adjusted to the voltage value of the target off-voltage.

[0074] Step 605: Read back the calibration error. According to the voltage value of the first voltage and / or the second voltage fed back by the feedback unit, the error between the current voltage value of the first voltage and the target on-voltage, and the error between the current voltage value of the second voltage and the target off-voltage can be calculated.

[0075] Step 606: Determine whether the error is greater than a preset value. If yes, continue to execute step 604, otherwise end the dynamic adjustment process.

[0076] In the case of continuing to execute step 604, the voltage value of the first voltage and / or the second voltage can be continuously adjusted according to the above error until the voltage value of the first voltage reaches the voltage value of the target on-voltage, and / or the voltage value of the second voltage reaches the voltage value of the target off-voltage.

[0077] It should be noted that the serial numbers of the steps in the embodiment do not represent the limitation of the execution order of the steps.

[0078] It can be understood that, in a specific implementation, the dynamic adjustment method can be realized in the form of a software program running in a processor integrated in a chip or a chip module. The method can also be realized in the form of software combined with hardware, and the application does not make any limitation.

[0079] The embodiment of the application adjusts the voltage value of the first voltage and / or the second voltage based on the ambient temperature of the laser radar, so that the light emitting device can maintain the consistency of the emission power when the ambient temperature changes, thereby ensuring the ranging accuracy of the laser radar. On the other hand, the voltage values of the first voltage and the second voltage can also be adjusted synchronously to reduce the difference between the first voltage and the second voltage without affecting the normal operation of the light emitting device, thereby reducing the energy loss of the laser radar.

[0080] In a non-limiting embodiment, please refer to Figure 7 The dynamic adjustment system can further include a plurality of voltage buses 701, a power supply module 702, and at least one switching device 703.

[0081] Each light emitting device 50 is connected to the power supply module 702 through one of the voltage buses; the light emitting devices 50 connected to the non-shared voltage bus are connected to one of the switching devices 703, and the switching device 703 is configured to control the on-off of the light emitting devices 50 connected to the same voltage bus.

[0082] The power supply module 702 outputs the first voltage to the voltage bus 701 and controls the light emitting devices 50 connected to the voltage bus 701 to be turned on through the switching device 703, so as to control the light emitting devices 50 to emit light. For example, the power supply module 702 provides the first voltage to the voltage bus HV_BUS_D, the voltage bus HV_BUS_D provides the first voltage to the light emitting device 51 and the light emitting device 52, and controls the light emitting device 52 connected to the voltage bus HV_BUS_D to be turned on through the switching device GaN2; and controls the light emitting device 51 connected to the voltage bus HV_BUS_D to be turned off through the switching device GaN1.

[0083] In a non-limiting embodiment, the second power supply module can provide the second voltage. Please refer to Figure 8The second power module can include a first control unit 801 and a filter unit 802. The first control unit 801 is configured to provide the second voltage. The filter unit 802 is configured to filter a pulse signal output by the control unit and output a filtered voltage to the first control unit 801. The first control unit 801 provides the second voltage according to the filtered voltage.

[0084] According to the embodiment of the present application, the pulse signal is filtered by the filter unit 802, which can ensure the stability of the filtered direct current voltage, thereby ensuring the stability of the second voltage regulation.

[0085] In a specific embodiment, the first control unit 801 can include a step-down controller, such as a Buck controller (as shown in 8011). The filter unit 802 can be a second-order RC filter circuit. Figure 8

[0086] Specifically, the second-order RC filter circuit can include an eighth resistor R8, a ninth resistor R9, an eighth capacitor C8 and a ninth capacitor C9. One end of the ninth resistor R9 is connected to the pulse signal. The other end of the ninth resistor R9 is coupled to one end of the eighth capacitor C8. The other end of the eighth capacitor C8 is grounded. One end of the eighth resistor R8 is coupled to the other end of the ninth resistor R9. The other end of the eighth resistor R8 is coupled to one end of the ninth capacitor C9. The other end of the ninth capacitor C9 is grounded.

[0087] Since the controller 8011 has no control end, and the feedback end (FB end) of the controller 8011 is a fixed voltage, the FB end voltage needs to be adjusted, that is, the voltage on the FB end is adjusted by PWM filtering (i.e., second-order RC filtering) to achieve the adjustment of the second voltage HV_L.

[0088] Further, the second power module can further include a conversion unit 803. The conversion unit 803 is configured to convert the pulse signal output by the control unit 302 into a conversion signal having a reference voltage. Specifically, the conversion signal can be a square wave signal having a reference voltage.

[0089] Specifically, the conversion unit 803 can include a gating unit. The control end of the gating unit is connected to the pulse signal output by the control unit. The first input end of the gating unit is grounded. The second input end of the gating unit is connected to the reference voltage VREF. The output end of the gating unit outputs the conversion signal. When the pulse signal is at a high level, the output end of the gating unit is connected to the second input end of the gating unit. When the pulse signal is at a low level, the output end of the gating unit is connected to the first input end of the gating unit.

[0090] In a specific embodiment, the gating unit can be a multiplexer (MUX), also known as a multiplexer.​

[0091] Specifically, the control end HV_L_CTRL of the multiplexer MUX is connected with the PWM control signal, and converts it into a square wave control signal of 0-VREF, which is output from the A end of the multiplexer. Since the voltage of the pulse signal output by the FPGA is not accurate enough, the reference voltage can be used for conversion to improve the accuracy of the control signal and ensure the stability of the pulse signal output direct current voltage.

[0092] Specifically, when the S end of the multiplexer MUX is high (i.e. the control end HV_L_CTRL is high), A=B2=VREF; when the S end of the multiplexer MUX is low (i.e. the control end HV_L_CTRL is low), A=B1=0. The PWM signal of the FPGA is converted into a PWM signal with reference to the reference source VREF through the multiplexer MUX.

[0093] In this embodiment, the filtered pulse signal can adjust the output voltage of the feedback end FB of the controller 8011, thereby adjusting the second voltage HV_L.

[0094] The calculation formula of the second voltage HV_L is as follows:

[0095]

[0096] Wherein, D is the duty ratio of the pulse signal, V REF is the reference voltage, V FB is the feedback end voltage of the controller 8011, V REF and V FB are fixed voltages.

[0097] Specifically, for the controller 8011, the first capacitor C1 and the second capacitor C2 are input capacitors, and the fifth capacitor C5 and the sixth capacitor C6 are output capacitors. The controller 8011 is internally integrated with a switch MOS1 (for connecting IN and SW) and a switch MOS2 (for connecting GND and SW). When the switch MOS1 is turned on (IN and SW are connected), the input power charges the inductor L1 through the switch MOS1, and the current of the inductor L1 linearly increases, which is used for energy storage; when the switch MOS2 is turned on (GND and SW are connected), the inductor L1 is connected to the ground through the left switch MOS2, and the current of the inductor L1 linearly decreases. In these two stages, the direction of the inductor current remains unchanged, and always flows to the fifth capacitor C5 and the sixth capacitor C6, i.e. powers the fifth capacitor C5 and the sixth capacitor C6. The on-time of the switch MOS1 and the switch MOS2 is controlled by the feedback of the fifth resistor R5 and the sixth resistor R6 through the FB terminal input to the controller 8011, i.e. the controller 8011 monitors the voltage at the FB terminal, and when the voltage at the FB terminal rises, the on-time of the switch MOS1 and the switch MOS2 increases accordingly, and when the voltage at the FB terminal decreases, the on-time of the switch MOS1 and the switch MOS2 decreases accordingly.

[0098] In one non-limiting embodiment of the present application, the first power module can provide a first voltage. The first power module comprises a second control unit for providing the first voltage, and a control terminal of the second control unit is connected to the pulse signal input to the control unit.

[0099] In one specific embodiment, the second control unit can comprise a boost controller, for example, a Boost controller.

[0100] For details, please refer to Figure 9 The input terminal VIN of the boost controller is connected to the second voltage HV_L, and the output terminal SW outputs the first voltage HV_H. The first capacitor C1 and the third capacitor C3 are input and output capacitors respectively, the magnetic bead FB1 is used to suppress high-frequency noise and spike interference of the input signal, and the second resistor R2 and the second capacitor C2 are loop compensation resistance and capacitance for adjusting the frequency domain response, avoiding overshoot, and making the voltage regulation more stable.

[0101] When the internal switch of the output terminal SW is turned on (controlled internally by the boost controller), the output terminal SW is equivalent to being connected to the ground, at this time the diode D1 is forward cut-off (both ends are connected to the ground), the current on the inductor L1 linearly increases, and the inductor L1 stores energy as an energy storage device; when the internal switch of the output terminal SW is turned off, since the current in the inductor L1 cannot change abruptly, it can only gradually charge the capacitor C3 through the diode D1, and the inductor current changes from linear increase to linear decrease. According to the inductor characteristics, the voltage of the output terminal SW at this time is higher than the input power, i.e. the first voltage HV_H, i.e. the boost is realized.

[0102] Compared with the common boost controller, the boost controller of the embodiment of the present application adjusts the feedback voltage through the PWM control signal driving control end HV_H_CTRL, which can adjust the first voltage HV_H in this way, and can also adjust the conduction time of the internal switch of the output end SW. Specifically, the boost controller monitors the voltage of the feedback end FB, and when the voltage of the feedback end FB rises, the conduction time of the internal switch of the output end SW increases accordingly, and when the voltage of the feedback end FB decreases, the conduction time of the internal switch of the output end SW decreases accordingly.

[0103] Referring to Figure 10 , Figure 10 A specific structure of the control end HV_H_CTRL is shown. The non-inverter can increase the driving capability, the transistor MOS1 and the transistor MOS2 correspond to the multiplexer MUX, which is used to ensure the stability of the PWM output DC voltage by using the reference source VBG, and the resistance R and the capacitor C form a filter circuit. The PWM control signal includes frequency and duty cycle, and the PWM control signal is input to the CTRL end to adjust the output voltage of the feedback end FB, that is, to adjust the duty cycle of the PWM control signal, so as to adjust the first voltage HV_H.

[0104] The calculation formula of the first voltage HV_H is as follows:

[0105]

[0106] Wherein, D is the PWM duty cycle output by the FPGA, V FB is the output voltage of the feedback end FB, V FB is a fixed value.

[0107] From the above formula 1 and formula 2, it can be seen that the voltage value of the first voltage and / or the second voltage can be adjusted by adjusting the duty cycle of the pulse signal, and the duty cycle of the pulse signal can be set according to the environmental temperature of the laser radar, so as to adjust the voltage value of the first voltage and / or the second voltage according to the environmental temperature; and further, on the one hand, by adjusting the first voltage, the light emitting device maintains the consistency of the emission power when the environmental temperature changes, thereby ensuring the ranging accuracy of the laser radar; on the other hand, by synchronously adjusting the voltage values of the first voltage and the second voltage, the difference between the first voltage and the second voltage is reduced without affecting the normal work of the light emitting device, thereby reducing the energy loss of the laser radar.

[0108] The embodiment of the present application also discloses a laser radar, which comprises the dynamic adjustment system of any one of the preceding embodiments. The laser radar further comprises a plurality of light emitting devices, and the laser radar emits a detection light beam through the plurality of light emitting devices.

[0109] Further, the laser radar further comprises a plurality of light receiving devices; the plurality of light receiving devices are used for receiving echo light beams reflected by the detection light beams by obstacles, and the plurality of light receiving devices are respectively arranged correspondingly to the plurality of light emitting devices.

[0110] Further, the laser radar further comprises a control unit, which is used for controlling the plurality of light emitting devices to emit the detection light beams in time division, and controlling the plurality of light receiving devices to receive the echo light beams correspondingly in time division. By controlling the plurality of light emitting devices to emit light in time division, the round-robin light emission of the light emitting devices can be realized.

[0111] It should be understood that the term "and / or" in the present application is only used to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in the present application means that the front and rear associated objects are in an "or" relationship.

[0112] The "plurality" appearing in the embodiments of the present application means two or more.

[0113] The first, second and the like appearing in the embodiments of the present application are only used for description and distinction of the description objects, and there is no order difference, nor represent a special limitation of the number of devices in the embodiments of the present application, which cannot constitute any limitation on the embodiments of the present application.

[0114] The "connection" appearing in the embodiments of the present application means direct connection or indirect connection and various connection modes to realize the communication between devices, which is not limited in the embodiments of the present application.

[0115] It should be understood that in the embodiments of the present application, the processor can be a central processing unit (CPU), and the processor can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0116] It should also be understood that the memory in the embodiments of the present application can be volatile or nonvolatile memory, or can include both volatile and nonvolatile memory. The nonvolatile memory can be read-only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), electrically EPROM (EEPROM), or flash memory. The volatile memory can be random access memory (RAM) used as external cache. By way of example, and not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous dynamic RAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0117] The above-described embodiments can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented by software, the above-described embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the processes or functions described in the embodiments of the present application are wholly or partially generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center through a wired or wireless manner. The computer-readable storage medium can be any available medium accessible by a computer or a data storage device such as a server, data center, or the like containing one or more available medium collections. It should be understood that in various embodiments of the present application, the size of the serial number of the above-described processes does not mean the execution order, and the execution order of the processes should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0118] In several embodiments provided in the present application, it should be understood that the disclosed methods, devices and systems can be implemented in other ways. For example, the above-described device embodiments are only illustrative; for example, the division of the units is only a logical function division, and actual implementation can have another division manner; for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed units can be indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0119] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place or distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0120] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically included separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or hardware plus software functional unit.

[0121] The integrated unit implemented in the form of software functional units can be stored in a computer readable storage medium. The software functional units stored in the storage medium include a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute part of the steps of the methods described in the various embodiments of the present application.

[0122] Although the present application has been disclosed with reference to the above embodiments, the application is not limited to the above. Any modifications and changes can be made without departing from the spirit and scope of the application, and the scope of protection of the present application should be subject to the scope defined by the claims.

Claims

1. A dynamic adjustment system for laser radar, characterized in that: The laser radar includes a plurality of light emitting devices, which emit light under the control of a first voltage and stop emitting light under the control of a second voltage; The dynamic adjustment system includes: Temperature monitoring unit, used to obtain ambient temperature; a control unit, configured to adjust the voltage values ​​of the first voltage and the second voltage according to the ambient temperature to adjust the operating state of the light emitting device, wherein the difference between the adjusted first voltage and the on-voltage of the light emitting device is less than a preset value, and the difference between the adjusted second voltage and the off-voltage of the light emitting device is less than a preset value; a power supply module, providing the first voltage and the second voltage for controlling whether the light emitting device emits light; a plurality of voltage buses, each light emitting device being connected to the power supply module via one of the voltage buses; At least one switching device is provided, and light emitting devices that do not share a common voltage bus are connected to one of the switching devices. The switching device is configured to control the on / off of the light emitting devices that are connected to the same voltage bus.

2. The dynamic adjustment system for laser radar according to claim 1, characterized in that: When the ambient temperature reaches a preset threshold, the control unit synchronously adjusts the first voltage and the second voltage according to the ambient temperature.

3. The dynamic adjustment system for laser radar according to claim 1, characterized in that: The control unit is used to adjust the voltage value of the first voltage according to the ambient temperature so that the light emitting device maintains a constant light emitting power.

4. The dynamic adjustment system for laser radar according to claim 1, characterized in that: The control unit is configured to adjust the voltage value of the second voltage according to the ambient temperature so that a difference between the adjusted voltage value of the second voltage and the voltage value of the first voltage is minimized.

5. The dynamic adjustment system for laser radar according to claim 1, characterized in that: The control unit obtains the voltage value of the first voltage and / or the second voltage according to the corresponding relationship between the first voltage and / or the second voltage and the ambient temperature.

6. The dynamic adjustment system for laser radar according to claim 1, characterized in that: The control unit outputs pulse signals with different duty cycles for adjusting the voltage value of the first voltage and / or the second voltage.

7. The dynamic adjustment system for laser radar according to claim 1, characterized in that: Also includes: A feedback unit is configured to obtain an adjusted voltage value of the first voltage and / or the second voltage.

8. The dynamic adjustment system for laser radar according to claim 7, characterized in that: The control unit outputs a pulse signal, and the control unit adjusts the duty cycle of the pulse signal according to the voltage value fed back by the feedback unit to adjust the voltage value of the first voltage and / or the second voltage.

9. The dynamic adjustment system for laser radar according to claim 1, characterized in that: The power supply module includes: a first power supply module and a second power supply module; The first power supply module is used to provide the first voltage for controlling the light emitting device to emit light, and the second power supply module is used to provide the second voltage for controlling the light emitting device to stop emitting light.

10. The dynamic adjustment system for laser radar according to claim 9, characterized in that: The second power supply module includes: The filtering unit is used to filter the pulse signal output by the control unit and output the filtered voltage to the first control unit, and the first control unit provides the second voltage according to the filtered voltage.

11. The dynamic adjustment system for laser radar according to claim 9, characterized in that: The second power supply module includes: a conversion unit, configured to convert the pulse signal output by the control unit into a conversion signal having a reference voltage; The filtering unit is used to filter the conversion signal and output the filtered voltage to the first control unit, and the first control unit provides the second voltage according to the filtered voltage.

12. The dynamic adjustment system for laser radar according to claim 11, characterized in that: The conversion unit includes: A gating unit, wherein the control end of the gating unit is connected to the pulse signal output by the control unit, the first input end of the gating unit is grounded, the second input end of the gating unit is connected to the reference voltage, and the output end of the gating unit outputs the conversion signal.

13. The dynamic adjustment system for laser radar according to claim 9, characterized in that: The first power supply module includes: The second control unit is used to provide the first voltage, and the control end of the second control unit is connected to the pulse signal input by the control unit.

14. The dynamic adjustment system for laser radar according to claim 1, characterized in that: The power supply module outputs the first voltage to the voltage bus, and controls the light emitting device connected to the voltage bus to be turned on through the switch device, so as to control the light emitting device to emit light.

15. A dynamic adjustment method for laser radar, characterized in that: The laser radar includes a plurality of light emitting devices, which emit light under the control of a first voltage and stop emitting light under the control of a second voltage; The dynamic adjustment method includes: Get the ambient temperature; adjusting the voltage values ​​of the first voltage and the second voltage according to the ambient temperature to adjust the working state of the light emitting device, wherein the difference between the adjusted first voltage and the on-voltage of the light emitting device is less than a preset value, and the difference between the adjusted second voltage and the off-voltage of the light emitting device is less than a preset value; Wherein, the laser radar further includes: a power supply module, providing the first voltage and the second voltage for controlling whether the light emitting device emits light; a plurality of voltage buses, each light emitting device being connected to the power supply module via one of the voltage buses; At least one switching device is provided, and light emitting devices that do not share a common voltage bus are connected to one of the switching devices. The switching device is configured to control the on / off of the light emitting devices that are connected to the same voltage bus.

16. The dynamic adjustment method for laser radar according to claim 15, characterized in that: The step of adjusting the voltage value of the first voltage and / or the second voltage according to the ambient temperature includes: adjusting the voltage value of the first voltage according to the ambient temperature so that the light emitting device maintains a constant light emitting power; And / or, the voltage value of the second voltage is adjusted according to the ambient temperature so that the difference between the adjusted voltage value of the second voltage and the voltage value of the first voltage is minimized.

17. The dynamic adjustment method for laser radar according to claim 15, characterized in that: The step of adjusting the voltage value of the first voltage and / or the second voltage according to the ambient temperature includes: The voltage values ​​of the first voltage and / or the second voltage are acquired according to a corresponding relationship between the first voltage and / or the second voltage and the ambient temperature.

18. A laser radar, characterized in that: comprising a light emitting device for emitting a detection light beam, wherein the light emitting device emits light under the control of a first voltage and stops emitting light under the control of a second voltage; a light receiving device for receiving an echo light beam reflected by an obstacle from the detection light beam; And a dynamic adjustment system according to any one of claims 1 to 14.

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