CN114442071A - Laser emission circuit, distance measurement method, laser radar and robot - Google Patents
Laser emission circuit, distance measurement method, laser radar and robot Download PDFInfo
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- CN114442071A CN114442071A CN202210106499.9A CN202210106499A CN114442071A CN 114442071 A CN114442071 A CN 114442071A CN 202210106499 A CN202210106499 A CN 202210106499A CN 114442071 A CN114442071 A CN 114442071A
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- 238000004146 energy storage Methods 0.000 claims abstract description 43
- 238000000034 method Methods 0.000 claims abstract description 19
- 239000003990 capacitor Substances 0.000 claims description 15
- 238000005259 measurement Methods 0.000 abstract description 11
- 238000001514 detection method Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 8
- 230000005669 field effect Effects 0.000 description 5
- 229910044991 metal oxide Inorganic materials 0.000 description 3
- 150000004706 metal oxides Chemical class 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 3
- 229910010271 silicon carbide Inorganic materials 0.000 description 3
- 229910002601 GaN Inorganic materials 0.000 description 2
- JMASRVWKEDWRBT-UHFFFAOYSA-N Gallium nitride Chemical compound [Ga]#N JMASRVWKEDWRBT-UHFFFAOYSA-N 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 230000010354 integration Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
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- 230000001052 transient effect Effects 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/481—Constructional features, e.g. arrangements of optical elements
- G01S7/4814—Constructional features, e.g. arrangements of optical elements of transmitters alone
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
- B25J—MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES
- B25J19/00—Accessories fitted to manipulators, e.g. for monitoring, for viewing; Safety devices combined with or specially adapted for use in connection with manipulators
- B25J19/02—Sensing devices
- B25J19/021—Optical sensing devices
- B25J19/022—Optical sensing devices using lasers
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
- G01S17/06—Systems determining position data of a target
- G01S17/08—Systems determining position data of a target for measuring distance only
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0068—Battery or charger load switching, e.g. concurrent charging and load supply
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- Remote Sensing (AREA)
- Electromagnetism (AREA)
- Power Engineering (AREA)
- Optics & Photonics (AREA)
- Robotics (AREA)
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- Optical Radar Systems And Details Thereof (AREA)
Abstract
The embodiment of the application relates to the technical field of laser radars, for example, to a laser emitting circuit, a ranging method, a laser radar and a robot. The laser emission circuit comprises a driving unit, an energy storage unit, a first switch and a laser generation unit, wherein the energy storage unit is electrically connected between the driving unit and the laser generation unit; the driving unit is configured to output a first voltage signal in a first state and a second voltage signal in a second state, the first voltage signal being greater than the second voltage signal; the first switch is electrically connected between the energy storage unit and the ground, is configured to perform on-off operation based on a first control signal, and forms a discharge loop communicating the laser generation unit, the energy storage unit and the ground when being conducted. The embodiment of the application can adopt the emergent laser with smaller power to detect the target in a short distance, so that the emergent laser can be emitted for many times on the premise of meeting the power consumption requirement, more detection data can be obtained, and the distance measurement precision of the target in a short distance is improved.
Description
Technical Field
The embodiment of the application relates to the technical field of laser radars, for example, to a laser emitting circuit, a ranging method, a laser radar and a robot.
Background
The laser radar is a radar system that detects a characteristic amount such as a position and a velocity of a target by emitting a laser beam. The working principle is to emit a certain power and frequency of emission signal (outgoing laser) to the target, then compare the received signal (reflected laser) reflected from the target with the emission signal, and after proper processing, obtain the relevant information of the target, such as the target distance.
The existing laser radar has the problem of low close-range measurement precision.
Disclosure of Invention
The embodiment of the application provides a laser emitting circuit, a distance measuring method, a laser radar and a robot, and the measuring precision of a close-range target can be improved.
In a first aspect, an embodiment of the present application provides a laser emission circuit, including a driving unit, an energy storage unit, a first switch, and a laser generating unit, where the energy storage unit is electrically connected between the driving unit and the laser generating unit;
the driving unit is configured to output a first voltage signal in a first state and a second voltage signal in a second state, the first voltage signal being greater than the second voltage signal;
the first switch is electrically connected between the energy storage unit and the ground, is configured to perform on-off operation based on a first control signal, and forms a discharge loop communicating the laser generation unit, the energy storage unit and the ground when being conducted;
the energy storage unit is configured to be charged based on the first voltage signal or the second voltage signal and to be discharged through the discharge circuit to provide electric energy for the laser generation unit;
the laser light generation unit is configured to emit laser light based on the electric energy.
In some embodiments, the laser emitting circuit further comprises:
the first resistor is electrically connected between the driving unit and the energy storage unit;
one end of the first switch is connected to a common connection point of the first resistor and the energy storage unit, and the other end of the first switch is grounded.
In some embodiments, the energy storage unit includes a capacitor electrically connected between the driving unit and the laser generating unit.
In some embodiments, the driving unit includes:
the first end of the driving switch is electrically connected with the first resistor, the second end of the driving switch is electrically connected with the first power supply connecting end, and the third end of the driving switch is electrically connected with the second power supply connecting end;
the driving switch is configured to turn on the first terminal and the second terminal based on a second control signal to place the driving unit in a first state and output a first voltage signal, and turn on the first terminal and the third terminal based on a third control signal to place the driving unit in a second state and output a second voltage signal.
In some embodiments, the driving switch comprises a first switch tube and a second switch tube;
the first end of the first switch tube and the first end of the second switch tube are electrically connected to a first common node, and the first common node is electrically connected to the first resistor;
the second end of the first switch tube is electrically connected with the first power supply connection end, the third end is used for receiving the second control signal, and the first switch tube is configured to switch on or off the connection between the first end and the second end of the first switch tube based on the second control signal;
the second terminal of the second switching tube is electrically connected to the second power connection terminal, the third terminal is used for receiving the third control signal, and the second switching tube is configured to turn on or off the connection between the first terminal and the second terminal of the second switching tube based on the third control signal.
In a second aspect, an embodiment of the present application further provides a ranging method, including:
emitting emergent laser with a first frequency based on first power to obtain first distance data, and obtaining a first target distance based on the first distance data;
if the first target distance is greater than or equal to a first threshold value, taking the first target distance as a target distance;
if the first target distance is smaller than or equal to a second threshold value, emitting emergent laser with a second frequency based on second power to obtain second distance data, obtaining a second target distance based on the second distance data, and taking the second target distance as the target distance;
wherein the second power is less than the first power, and the second frequency is greater than the first frequency.
In some embodiments, the method further comprises:
if the first target distance is larger than the second threshold and smaller than the first threshold, emitting emergent laser with a third frequency based on third power to obtain third distance data, obtaining a third target distance based on the third distance data, and taking the third target distance as the target distance;
wherein the third frequency is less than the second frequency, and the third power is greater than or equal to the second power.
In a third aspect, an embodiment of the present application further provides a laser radar including the laser emitting circuit of the claim.
In some embodiments, the lidar further includes a control unit, specifically including:
at least one processor, and
a memory communicatively coupled to the at least one processor, wherein,
the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method described above.
In a fourth aspect, an embodiment of the present application further provides a robot, including the laser radar described above.
Compared with the prior art, the driving unit of the embodiment of the application can output the first voltage signal and the second voltage signal, and the first voltage signal is larger than the second voltage signal. The energy storage unit is charged based on the first voltage signal, can store more electric energy, and can provide larger current for the laser generation unit when discharging, so that the laser generation unit emits higher-power emergent laser. Likewise, based on the second voltage signal, the laser generating unit can emit the outgoing laser light with a smaller power. The short-distance target can be detected by adopting the emergent laser with lower power, so that the emergent laser can be emitted for many times on the premise of meeting the power consumption requirement, more detection data can be obtained, and the distance measurement precision of the short-distance target can be improved.
Drawings
One or more embodiments are illustrated by way of example in the accompanying drawings, which are not to be construed as limiting the embodiments, in which elements having the same reference numerals are identified as similar elements, and in which the drawings are not to be construed as limited except as specifically noted.
FIG. 1 is a schematic block diagram of an embodiment of a lidar according to the present application;
FIG. 2 is a schematic diagram of a lidar according to an embodiment of the present disclosure;
FIG. 3 is a schematic structural diagram of a laser emitting circuit according to an embodiment of the present application;
FIG. 4 is a schematic structural diagram of a laser emitting circuit according to an embodiment of the present application;
FIG. 5 is a schematic structural diagram of a laser emitting circuit according to an embodiment of the present application;
FIG. 6 is a schematic structural diagram of a laser emitting circuit according to an embodiment of the present application;
FIG. 7 is a schematic structural diagram of a laser emitting circuit according to an embodiment of the present application;
FIG. 8 is a schematic diagram of a hardware configuration of a control unit in an embodiment of a laser transmitter circuit of the present application;
FIG. 9 is a flow chart of one embodiment of a ranging method of the present application;
fig. 10 is a flowchart of another embodiment of the ranging method of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described in detail in the following with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present.
In addition, the technical features mentioned in the embodiments of the present application described below may be combined with each other as long as there is no structural conflict between the technical features.
The working principle of the laser radar is to emit outgoing laser outwards, receive reflected laser after the outgoing laser is reflected by an obstacle (target), and compare the outgoing laser with the reflected laser to obtain the distance of the obstacle.
Fig. 1 shows a structure of laser radar 100, which includes a laser transmitter circuit 10 and a laser receiver circuit 20, where laser transmitter circuit 10 is used for transmitting outgoing laser light, and laser receiver circuit 20 is used for receiving reflected laser light.
The ranging principle of the laser radar is described below by taking a TOF laser radar as an example, and the TOF laser radar calculates the target distance by using the time difference between the transmission and the reception of laser light. Referring to fig. 2, the time difference between the laser emission and the laser reception is T, the path of the laser in the process is twice the target distance, and the target distance D is 1/2C × T, where C is the speed of light.
The emergent laser can be emitted at any suitable power and frequency, the emergent laser with higher power can reach a longer distance and a target with a longer measuring position, but the high power can cause high power consumption. In view of laser safety, the power consumption of the current laser radar is limited.
In some embodiments, the short-distance target and the long-distance target are measured at the same power and the same frequency, so that the control is simple.
In other embodiments, the near target and the far target are measured at different powers and different frequencies, respectively. For example, when a long-distance target is measured, high-power outgoing laser light is emitted, and when a short-distance target is measured, low-power outgoing laser light is emitted. Because the power consumption that the outgoing laser of miniwatt leads to is little, then can satisfy under the prerequisite that the power consumption required, with higher frequency transmission outgoing laser to obtain more range finding data, the curve fitting of being convenient for improves closely range finding precision.
Compared with the embodiment of measuring the target with the same power and the same frequency, the method has the advantages that the short-distance target and the long-distance target are measured with different powers and different frequencies respectively, and the distance measurement precision of the short-distance target can be improved on the premise of ensuring the measurement range requirement and the power consumption requirement
The embodiment of the application provides a laser emitting circuit which can emit high-power emergent laser and low-power emergent laser respectively. The laser emitting circuit comprises a driving unit, an energy storage unit, a laser generating unit and a first switch, wherein the energy storage unit is electrically connected between the driving unit and the laser generating unit.
Wherein the driving unit is configured to output a first voltage signal in a first state and a second voltage signal in a second state. An energy storage unit configured to be charged based on the first voltage signal or the second voltage signal. That is, when the driving unit outputs the first voltage signal, the energy storage unit may be charged based on the first voltage signal, and when the driving unit outputs the second voltage signal, the energy storage unit may be charged based on the second voltage signal. In this embodiment, the first voltage signal is greater than the second voltage signal.
The first switch is electrically connected between the energy storage unit and the ground, is configured to perform on-off operation based on a first control signal, and forms a discharge loop communicating the laser generation unit, the energy storage unit and the ground when being conducted. The energy storage unit can discharge through the discharge loop, and when the energy storage unit discharges through the discharge loop, the energy storage unit provides electric energy for the laser generation unit. The laser generating unit emits laser light based on electric energy.
When the driving unit is in a first state and outputs a first voltage signal, the energy storage unit is charged based on the first voltage signal and stores certain electric energy. When the first switch is switched on based on the first control signal, a discharge loop which is communicated with the laser generation unit, the energy storage unit and the ground is formed, and the energy storage unit discharges through the discharge loop to generate instantaneous current. The laser generating unit emits laser light driven by the current.
The first voltage signal is larger, so that the energy storage unit can store more electric energy, and larger current can be provided for the laser generation unit during discharging, so that the laser generation unit emits higher-power emergent laser.
Also, based on the same principle, the laser generating unit can emit the outgoing laser light with a smaller power based on the second voltage signal.
The laser emitting circuit of the embodiment of the application can emit emergent laser with smaller power and can emit emergent laser with larger power. The short-distance target can be detected by adopting the emergent laser with smaller power, so that the emergent laser can be emitted for many times on the premise of meeting the power consumption requirement, more detection data can be obtained, and the distance measurement precision of the short-distance target can be improved.
Fig. 3 shows a structure of the laser transmitter circuit 10, in which the energy storage unit 12 is electrically connected between the driving unit 11 and the laser generating unit 13, one end of the first switch 14 is connected to a common connection point of the driving unit 11 and the energy storage unit 12, and the other end is grounded.
Fig. 4 shows another structure of the laser emitting circuit 10, and in the embodiment shown in fig. 4, the laser emitting circuit 10 further includes a first resistor R1, and the first resistor R1 is electrically connected between the driving unit 11 and the energy storage unit 12.
The energy storage unit may be any suitable device capable of being charged and discharged, and when the driving unit outputs the first voltage signal or the second voltage signal, the energy storage unit may be charged based on the first voltage signal or the second voltage signal to store electric energy. When the first switch is switched on and the discharge loop is formed, the energy storage unit can discharge through the discharge loop to provide electric energy for the laser generation unit so as to enable the laser generation unit to generate laser.
Fig. 5 shows a configuration of the energy storage unit, and in the embodiment shown in fig. 5, the energy storage unit 12 comprises a capacitor C1, and a torch C1 is electrically connected between the common connection of the first resistor R1 and the first switch 14 and the laser generating unit 13.
The laser generating unit 13 may be any suitable device capable of generating laser light based on conversion of electrical energy, for example, an electrically-excited laser.
The first switch 14 may be a gan power device, but any other suitable switch may be used, such as at least one of a metal-oxide semiconductor field effect transistor, an insulated gate bipolar transistor, an integrated gate commutated thyristor, a gate turn-off thyristor, a junction gate field effect transistor, a MOS controlled thyristor, a silicon carbide based power device, a thyristor, and a signal relay.
The drive unit 11 may be any suitable device capable of generating a higher voltage signal and a lower voltage signal. Fig. 5 shows a structure of the driving unit 11, and in the embodiment shown in fig. 5, the driving unit 11 includes a driving switch, a first terminal of the driving switch is electrically connected to the first resistor R1, a second terminal of the driving switch is electrically connected to the first power connection terminal VCCH, and a third terminal of the driving switch is electrically connected to the second power connection terminal VCCL.
Wherein the driving switch is configured to turn on the first terminal and the second terminal based on a second control signal to place the driving unit in a first state and output a first voltage signal, and to turn on the first terminal and the third terminal based on a third control signal to place the driving unit in a second state and output a second voltage signal.
The voltage that first power connection VCCH provided is higher than second power connection VCCL, and when first end and second end switched on, first end intercommunication first power connection VCCH, first power connection VCCH provides higher first voltage signal to first resistance R1. When the third terminal and the second terminal are conducted, the first terminal is connected to the second power connection terminal VCCL, and the second power connection terminal VCCL provides a lower second voltage signal to the first resistor R1.
The drive switch may be any suitable switching device having three terminals that can form two conduction paths, such as a single pole double throw switch. Fig. 6 shows a structure of the driving switch, and in the embodiment shown in fig. 6, the driving switch includes a first switching tube Q1 and a second switching tube Q2. A first terminal of the first switch transistor Q1 and a first terminal of the second switch transistor Q2 are electrically connected to a first common node N1, and the first common node N1 is electrically connected to a first resistor R1.
The second terminal of the first switch Q1 is electrically connected to the first power connection VCCH, the third terminal is used for receiving the second control signal, and the first switch Q1 is configured to turn on or off the connection between the first terminal and the second terminal of the first switch Q1 based on the second control signal.
The second terminal of the second switching tube Q2 is electrically connected to the second power connection terminal VCCL, the third terminal is configured to receive the third control signal, and the second switching tube Q2 is configured to turn on or off the connection between the first terminal and the second terminal of the second switching tube Q2 based on the third control signal.
When the first switch transistor Q1 switches on the connection between the first terminal and the second terminal of the first switch transistor Q1 based on the second control signal, the first power connection terminal VCCH switches on the first resistor R1, and the first power connection terminal VCCH provides a higher first voltage signal to the first resistor R1. When the second switching transistor Q2 switches on the connection between the first terminal and the second terminal of the second switching transistor Q2 based on the third control signal, the second power connection terminal VCCL switches on the first resistor R1, and the second power connection terminal VCCL provides a lower second voltage signal to the first resistor R1.
In fig. 6, the first switch Q1 is illustrated as a P-type metal-oxide semiconductor field effect transistor, and besides, the first switch Q1 may be any suitable device capable of turning on or off the connection between the first power connection terminal VCCH and the first resistor R1, such as at least one of a triode, an N-type metal-oxide semiconductor field effect transistor, an insulated gate bipolar transistor, an integrated gate commutated thyristor, a gate turn-off thyristor, a junction gate field effect transistor, a MOS controlled thyristor, a gallium nitride based power device, a silicon carbide based power device, a silicon controlled thyristor, and a signal relay.
In addition to the structure of the second switch Q2 illustrated in fig. 6 as a P-type mosfet, the second switch Q2 may be any suitable device capable of turning on or off the connection between the second power connection VCCL and the first resistor R1, such as at least one of a triode, an N-type mosfet, an igbt, an integrated gate commutated thyristor, a gate turn-off thyristor, a junction gate fet, a MOS-controlled thyristor, a gallium nitride-based power device, a silicon carbide-based power device, a thyristor, and a signal relay.
In other embodiments, referring to fig. 7, the laser generating circuit 10 further includes a control unit 15, and the control unit 15 is configured to send out control signals, for example, send out a first control signal to control the first switch to be turned on or off, send out a second control signal to control the first switch Q1 to be turned on or off, send out a third control signal to control the second switch Q2 to be turned on or off, and so on.
Fig. 8 shows a structure of the control unit 15, which includes a processor 151 and a memory 152, wherein the memory 152 is a non-volatile computer-readable storage medium that can be used to store a non-volatile software program, non-volatile computer-executable program instructions. Further, the memory 152 may include high speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid state storage device.
The processor 151 performs various functions of the control unit and processes data, for example, issuing control signals or implementing a ranging method according to any of the embodiments of the present application, by running or executing software programs stored in the memory 151 and calling data stored in the memory 152.
The processor 151 may be one or more, and one processor 151 is illustrated in fig. 8 as an example. The processor 151 and the memory 152 may be connected by a bus or other means, and fig. 8 illustrates the connection by a bus as an example.
Processor 151 may include a Central Processing Unit (CPU), Digital Signal Processor (DSP), application specific integrated circuit (ASI C), Field Programmable Gate Array (FPGA) device, or the like. Processor 151 may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
The working principle of the embodiment of the present application is described below by taking the embodiment shown in fig. 6 as an example, when the control unit controls the first switching tube Q1 to be turned on, the first power connection terminal VCCH is connected to the first resistor R1, the first power connection terminal VCCH provides a first voltage signal to the first resistor R1, the first voltage signal charges the capacitor C1 through the first resistor R1, and the capacitor C1 stores a certain amount of electric energy after charging.
When the control unit sends a first control signal to the first switch 14 to turn on the first switch 14, the connection between the capacitor C1 and the ground is established, the capacitor C1 discharges, a transient current is generated to supply power to the laser generating unit 13, and the laser generating unit 13 generates laser light. Since the first voltage signal is larger, the laser power emitted by the laser generating unit 13 is larger at this time, which is called as a first power, and the laser with the first power can be used for detecting a target at a longer distance. Of course, the laser of the first power may also be used to detect a target at a closer distance.
When the control unit controls the second switching tube Q2 to be switched on, the second power connection terminal VCCL is connected to the first resistor R1, the second power connection terminal VCCL provides a second voltage signal to the first resistor R1, the second voltage signal charges the capacitor C1 through the first resistor R1, and the capacitor C1 stores a certain amount of electric energy after charging.
When the control unit sends a first control signal to the first switch 14 to turn on the first switch 14, the connection between the capacitor C1 and the ground is established, the capacitor C1 discharges, a transient current is generated to supply power to the laser generating unit 13, and the laser generating unit 13 generates laser light. Since the second voltage signal is smaller, the laser power emitted by the laser generating unit 13 is smaller at this time, which is called as a second power, and the laser with the second power can be used for detecting the object at a shorter distance.
In some embodiments, the control unit 15 uses the laser with the first power and the laser with the second power to detect a target with a longer distance and a target with a shorter distance, respectively, so as to improve the distance measurement accuracy of a target with a shorter distance on the premise of ensuring the distance measurement range and power consumption requirements.
It should be noted that the above-mentioned "voltage signal is larger" and "voltage signal is smaller" do not refer to a specific certain voltage, but refer to that the first voltage signal is larger than the second voltage signal relatively. Then, the second voltage signal is smaller for the first voltage signal and the first voltage signal is larger for the second voltage signal.
In the embodiments shown in the above figures, the resistor is represented as a single resistor, and the capacitor is represented as a single capacitor. In other embodiments, the resistor may also be an integration of series, parallel or series-parallel resistors, and the capacitor may also be an integration of series, parallel or series-parallel capacitors.
The laser radar in the embodiment of the application can be a triangular laser radar or a TOF laser radar. The laser transmitting circuit of the embodiment of the application can be applied to any other suitable occasions needing two outgoing lasers with different powers besides being used for the laser radar.
As shown in fig. 9, an embodiment of the present application further provides a ranging method, which may be applied to a laser radar and is executed by a control device in the laser radar, for example, the control unit 15 according to the foregoing embodiment, where the method includes:
s1: emitting laser with first power based on first frequency to obtain first distance data, and obtaining a first target distance based on the first distance data.
S2: and if the first target distance is greater than or equal to a first threshold value, taking the first target distance as a target distance.
S3: and if the first target distance is smaller than or equal to a second threshold value, emitting emergent laser with second power based on second frequency to obtain second distance data, obtaining a second target distance based on the second distance data, and taking the second target distance as the target distance.
Wherein the second power is less than the first power, and the second frequency is greater than the first frequency.
That is, when the laser radar measures distance, the first power of the outgoing laser is first emitted at the first frequency, and because the first power is relatively large, the first power of the outgoing laser may be first emitted before the distance to the target is unclear, so as to obtain the first distance data based on the first power of the outgoing laser, and obtain the first target distance based on the first distance data.
If the first target distance obtained based on the first distance data is larger than or equal to the first threshold, the target is a long-distance target, only the emergent laser with larger power can be detected, the laser is not emitted, and the first target distance is taken as the final target distance.
If the first target distance is smaller than or equal to the second threshold, the target is a close-distance target, and the outgoing laser with the larger power and the outgoing laser with the smaller power can be detected. In order to improve the precision of the short-distance measurement, the power and the frequency of the emergent laser can be changed, the emission frequency of the emergent laser is improved, and the emission power of the emergent laser is reduced so as to meet the power consumption requirement. Because the frequency of the emergent laser is increased, more distance measurement data can be obtained, curve fitting is facilitated, and distance measurement precision is improved.
That is, the second power of the outgoing laser light is emitted at the second frequency, the second distance data is obtained based on the second power of the outgoing laser light, and the second target distance is obtained based on the second distance data. Since the second target distance is more accurate than the first target distance, the second target distance is taken as the final target distance.
The first threshold and the second threshold may be set appropriately according to the performance of the laser radar and the application of the laser radar, and may be the same value or different values.
In other embodiments, referring to fig. 10, in addition to steps S1, S2, and S3, the method further includes step S4:
s4, if the first target distance is larger than the second threshold and smaller than the first threshold, emitting laser with third power based on a third frequency to obtain third distance data, obtaining a third target distance based on the third distance data, and taking the third target distance as the target distance; the third frequency is smaller than the second frequency and larger than the first frequency, and the third power is larger than or equal to the second power and smaller than the first power.
In this embodiment, the ranging range is divided into three segments, which are greater than or equal to the first threshold, greater than the second threshold and less than the first threshold, and less than or equal to the second threshold.
The laser radar firstly emits emergent laser with first power at first frequency to obtain a first target distance, and the distance of the target can be roughly judged according to the first target distance. The power and frequency settings of the low power exit laser are then confirmed based on the first target distance to achieve automatic dynamic adjustment.
If the target is far and the first target distance is greater than or equal to the first threshold, the laser is not emitted any more, and the first target distance is taken as the final target distance.
If the target distance is medium, the first target distance is larger than the second threshold and smaller than the first threshold, the emergent power is properly reduced, the emergent frequency is properly increased, the emergent laser with the third power is emitted at the third frequency, third distance data is obtained based on the emergent laser with the third power, and the third target distance is obtained based on the third distance data. And replacing the first target distance with the third target distance as the final target distance, because the precision of the third target distance is higher than that of the first target distance.
If the target distance is close and the first target distance is smaller than or equal to the second threshold, reducing the emergent power and increasing the emergent frequency again, emitting the emergent laser with the second power at the second frequency to obtain a second target distance, and taking the second target distance as the final target distance.
The above only illustrates the case of dividing the ranging range into three segments, and in other embodiments, the ranging range may be divided into more segments in order to achieve more precise control.
The first power is greater than the second power, the first power is greater than the third power, the second power and the third power may be the same or different, and the actual value of each power may be set to an appropriate value based on the ranging capability of the laser.
It should be noted that the first distance data, the second distance data, and the third distance data refer to initial distance data obtained by emitting laser light and reflecting laser light, and the first target distance, the second target distance, and the third target distance refer to distances of targets obtained by performing numerical calculation on the initial distance data.
The embodiment of the application further provides a robot, including the laser radar of any one of the above embodiments, wherein the robot can be any suitable robot which needs to utilize laser radar for ranging, and the robot can have a moving capability, such as a sweeping robot, a service robot and the like.
The above description is only an example of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings, or which are directly or indirectly applied to other related technical fields, are intended to be included within the scope of the present application.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; within the context of the present application, where technical features in the above embodiments or in different embodiments can also be combined, the steps can be implemented in any order and there are many other variations of the different aspects of the present application as described above, which are not provided in detail for the sake of brevity; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and these modifications or substitutions do not depart from the scope of the technical solutions of the embodiments of the present application.
Claims (10)
1. A laser emission circuit is characterized by comprising a driving unit, an energy storage unit, a first switch and a laser generation unit, wherein the energy storage unit is electrically connected between the driving unit and the laser generation unit;
the driving unit is configured to output a first voltage signal in a first state and a second voltage signal in a second state, the first voltage signal being greater than the second voltage signal;
the first switch is electrically connected between the energy storage unit and the ground, is configured to perform on-off operation based on a first control signal, and forms a discharge loop communicating the laser generation unit, the energy storage unit and the ground when being conducted;
the energy storage unit is configured to be charged based on the first voltage signal or the second voltage signal and to be discharged through the discharge circuit to provide electric energy for the laser generation unit;
the laser light generation unit is configured to emit laser light based on the electric energy.
2. The circuit of claim 1, further comprising:
the first resistor is electrically connected between the driving unit and the energy storage unit;
one end of the first switch is connected to a common connection point of the first resistor and the energy storage unit, and the other end of the first switch is grounded.
3. The circuit of claim 2, wherein the energy storage unit comprises a capacitor electrically connected between the driving unit and the laser generating unit.
4. A circuit according to claim 2 or 3, wherein the drive unit comprises:
the first end of the driving switch is electrically connected with the first resistor, the second end of the driving switch is electrically connected with the first power supply connecting end, and the third end of the driving switch is electrically connected with the second power supply connecting end;
the driving switch is configured to turn on the first terminal and the second terminal based on a second control signal to place the driving unit in a first state and output a first voltage signal, and turn on the first terminal and the third terminal based on a third control signal to place the driving unit in a second state and output a second voltage signal.
5. The circuit of claim 4, wherein the driving switch comprises a first switch tube and a second switch tube;
the first end of the first switch tube and the first end of the second switch tube are electrically connected to a first common node, and the first common node is electrically connected to the first resistor;
the second end of the first switch tube is electrically connected with the first power supply connection end, the third end is used for receiving the second control signal, and the first switch tube is configured to switch on or off the connection between the first end and the second end of the first switch tube based on the second control signal;
the second terminal of the second switching tube is electrically connected to the second power connection terminal, the third terminal is used for receiving the third control signal, and the second switching tube is configured to turn on or off the connection between the first terminal and the second terminal of the second switching tube based on the third control signal.
6. A method of ranging, comprising:
emitting emergent laser with first power based on first frequency to obtain first distance data, and obtaining a first target distance based on the first distance data;
if the first target distance is larger than or equal to a first threshold value, taking the first target distance as a target distance;
if the first target distance is smaller than or equal to a second threshold value, emitting emergent laser with second power based on second frequency to obtain second distance data, obtaining a second target distance based on the second distance data, and taking the second target distance as the target distance;
wherein the second power is less than the first power, and the second frequency is greater than the first frequency.
7. The method of claim 6, further comprising:
if the first target distance is larger than the second threshold and smaller than the first threshold, emitting emergent laser with third power based on a third frequency to obtain third distance data, obtaining a third target distance based on the third distance data, and taking the third target distance as the target distance;
the third frequency is smaller than the second frequency and larger than the first frequency, and the third power is larger than or equal to the second power and smaller than the first power.
8. A lidar characterized by comprising the laser transmitter circuit of any of claims 1-5.
9. The lidar of claim 8, further comprising a control unit, the control unit comprising:
at least one processor, and
a memory communicatively coupled to the at least one processor, wherein,
the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method of claim 6 or 7.
10. A robot comprising a lidar according to claim 8 or 9.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108181621A (en) * | 2016-12-08 | 2018-06-19 | 北京万集科技股份有限公司 | A kind of bidifly light drive circuit and scanning type laser radar ranging equipment and method |
| CN108445506A (en) * | 2018-05-11 | 2018-08-24 | 北醒（北京）光子科技有限公司 | A kind of driving radiating circuit, laser radar and measurement method |
| CN109324633A (en) * | 2018-09-27 | 2019-02-12 | Oppo广东移动通信有限公司 | Control method and device, flight time device, terminal and computer readable storage medium |
| CN109696691A (en) * | 2018-12-26 | 2019-04-30 | 北醒（北京）光子科技有限公司 | A kind of laser radar and its method measured, storage medium |
| WO2021026709A1 (en) * | 2019-08-12 | 2021-02-18 | 深圳市速腾聚创科技有限公司 | Laser radar system |
| CN113167871A (en) * | 2018-12-24 | 2021-07-23 | 北京航迹科技有限公司 | Adaptive power control for pulsed laser diodes |
| US20210333362A1 (en) * | 2019-01-09 | 2021-10-28 | SZ DJI Technology Co., Ltd. | Light emitting device, distance measuring device and mobile platform |
-
2022
- 2022-01-28 CN CN202210106499.9A patent/CN114442071A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108181621A (en) * | 2016-12-08 | 2018-06-19 | 北京万集科技股份有限公司 | A kind of bidifly light drive circuit and scanning type laser radar ranging equipment and method |
| CN108445506A (en) * | 2018-05-11 | 2018-08-24 | 北醒（北京）光子科技有限公司 | A kind of driving radiating circuit, laser radar and measurement method |
| CN109324633A (en) * | 2018-09-27 | 2019-02-12 | Oppo广东移动通信有限公司 | Control method and device, flight time device, terminal and computer readable storage medium |
| CN113167871A (en) * | 2018-12-24 | 2021-07-23 | 北京航迹科技有限公司 | Adaptive power control for pulsed laser diodes |
| CN109696691A (en) * | 2018-12-26 | 2019-04-30 | 北醒（北京）光子科技有限公司 | A kind of laser radar and its method measured, storage medium |
| US20210333362A1 (en) * | 2019-01-09 | 2021-10-28 | SZ DJI Technology Co., Ltd. | Light emitting device, distance measuring device and mobile platform |
| WO2021026709A1 (en) * | 2019-08-12 | 2021-02-18 | 深圳市速腾聚创科技有限公司 | Laser radar system |
Non-Patent Citations (1)
| Title |
|---|
| 陈祚海 等: "高速窄脉冲激光器驱动电路设计", 科技信息, no. 17, 15 June 2011 (2011-06-15), pages 548 - 549 * |
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