WO2020142956A1

WO2020142956A1 - Discharge circuit for distance measuring device, distributed radar system and mobile platform

Info

Publication number: WO2020142956A1
Application number: PCT/CN2019/071043
Authority: WO
Inventors: 陆龙; 何欢; 陈江波; 边亚斌
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2019-01-09
Filing date: 2019-01-09
Publication date: 2020-07-16
Also published as: CN111670527A

Abstract

Provided are a discharge circuit (200) for a distance measuring device, a distributed radar system (100) and a mobile platform, wherein the discharge circuit (200) for the distance measuring device is used to discharge when an input power supply (VIN) is powered off, the discharge circuit (200) comprises: a comparison module (20), which is used to compare the magnitude of a voltage divider (VIN1) generated by the input power supply (VIN) with a reference voltage (VREF), and generate a comparison signal (VOUT1); a direction detection module (30), which is used to generate a detection signal (VQ) indicating whether the input power supply (VIN) is in a power-off state or a non-power-off state according to the comparison signal (VOUT1); and a discharge module (40), which is used to determine whether to discharge according to the detection signal (VQ). The direction detection module (30) determines whether the input power supply (VIN) is in the power-off state or the non-power-off state, so that it does not operate during power-on of the input power supply (VIN) to ensure that a power supply circuit is fully charged quickly, without additional energy loss, and operates during power-off of the input power supply (VIN) and discharges the residual charge on the power supply circuit to ensure the stability of a circuit system.

Description

Discharge circuit, distributed radar system and movable platform for distance measuring device

Instructions

Technical field

The present invention generally relates to the technical field of radar, and more particularly to a discharge circuit, a distributed radar system and a movable platform for a distance measuring device.

Background technique

In practical applications, radar is often used to detect target scenes. Taking lidar as an example, the principle is to actively emit laser pulse signals to the outside, detect the reflected echo signal, and judge the distance of the measured object according to the time difference between transmission and reception; combined with the information of the direction of the optical pulse emission, you can Get the 3D depth information of the target scene.

In order to obtain the three-dimensional depth information of the target scene in various directions, a distributed radar system is proposed to detect the three-dimensional depth information of the target scene in various directions by arranging radars at different positions. In a multi-distributed radar system, because the control system is externally connected to multiple radars, the power supply circuit has a large power, and the input power VIN generally generates a stable voltage VDD through some power management circuits to power the system. In order to ensure the stability of the VDD voltage, there are many capacitive loads in these power management circuits. When the input power supply is powered off, the charge accumulated on the capacitive load is difficult to be discharged, resulting in the circuit still having residual charge for a long period of time after power off. This will bring unstable factors to the circuit system and affect the stability of the circuit system, such as abnormal secondary startup and abnormal power-on and power-off timing.

Summary of the invention

The present invention has been proposed to solve at least one of the above problems. The invention provides a discharge circuit for a distance measuring device, which can discharge when the input power supply is powered off. The discharge circuit does not work when the input power supply is powered on, which can ensure that the power supply circuit is quickly charged and there is no additional energy loss. While working in the input power-off process, the residual charge on the power supply circuit is discharged to ensure the stability of the circuit system.

Specifically, an embodiment of the present invention provides a discharge circuit for a distance measuring device for discharging when an input power source is powered off, and the discharge circuit includes:

A comparison module, used to compare the voltage of the input power supply with the reference voltage and generate a comparison signal;

A direction detection module, configured to generate a detection signal indicating whether the input power is in a power-off state or a non-power-off state according to the comparison signal;

The discharge module is used to determine whether to discharge according to the detection signal.

An embodiment of the present invention also provides a distributed radar system, which includes:

One or more radars;

A power supply circuit that generates an operating voltage for one or more of the radars based on the input power;

And the discharge circuit as described above, the current input terminal of the discharge circuit is connected to the output terminal of the power supply circuit, and the output terminal of the discharge circuit is grounded.

An embodiment of the present invention also provides a movable platform, which includes:

body;

A power system, installed on the fuselage, is used to provide power to the movable platform;

And the distributed radar system as described above.

Embodiments of the present invention provide a discharge circuit, a distributed radar system, and a movable platform for a distance measuring device. The direction detection module determines whether the input power is in a power-off state or a non-power-off state, so that the input power Does not work during the power-on process to ensure that the power supply circuit is fully charged without additional energy loss, and works during the input power-off process to discharge the residual charge on the power supply circuit to ensure the stability of the circuit system.

BRIEF DESCRIPTION

FIG. 1 shows a schematic block diagram of a distributed radar system according to an embodiment of the present invention;

2 shows a schematic block diagram of a discharge circuit for a distance measuring device according to an embodiment of the invention;

3 is a diagram showing the relationship between the comparison signal of the comparison module and the input power supply voltage in the discharge circuit shown in FIG. 2;

4 shows a schematic block diagram of a distance measuring device according to an embodiment of the present invention;

FIG. 5 shows a schematic structural diagram of a distance detection device according to an embodiment of the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the present invention more obvious, an exemplary embodiment according to the present invention will be described in detail below with reference to the drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited by the exemplary embodiments described herein. Based on the embodiments of the present invention described in the present invention, all other embodiments obtained by those skilled in the art without paying any creative work should fall within the protection scope of the present invention.

In the following description, a large number of specific details are given in order to provide a more thorough understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features known in the art are not described.

It should be understood that the present invention can be implemented in different forms and should not be interpreted as being limited to the embodiments presented herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terminology used herein is for describing specific embodiments only and is not intended as a limitation of the present invention. As used herein, the singular forms "a", "an", and "said/the" are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms "composition" and/or "comprising", when used in this specification, determine the existence of the described features, integers, steps, operations, elements and/or components, but do not exclude one or more other The presence or addition of features, integers, steps, operations, elements, components, and/or groups. As used herein, the term "and/or" includes any and all combinations of the listed items.

In order to thoroughly understand the present invention, detailed steps and detailed structures will be proposed in the following description in order to explain the technical solutions proposed by the present invention. However, in addition to these detailed descriptions, the present invention may have other embodiments.

FIG. 1 shows a schematic block diagram of a distributed radar system according to an embodiment of the present invention. As shown in FIG. 1, the distributed radar system 100 includes a control system 10 and N radars. N radars are distributed at different positions to detect object information at different positions/directions. The control system 10 detects objects according to N radars The information is comprehensively processed to understand the object information of the surrounding environment. For example, after distributing such a distributed radar system on a car, N radars are used to detect information about objects in different directions around the car, so as to understand the information about objects around the car.

The control system 10 may include one or more processors for receiving data sent by the radar 1-N, processing the data, and controlling the work of the radar 1-N and other modules. The control system 10 is connected to the N radar interfaces. The radar can be connected to the radar interface through the transmission cable 11 to connect the radar to the control system 10, so that the control system 10 receives the radar data and controls the radar.

The radar may be lidar, ultrasonic radar, millimeter wave radar, or other ranging devices or distance detection devices.

In this distributed radar system, the control system 10 is externally connected to multiple radars, and the power supply circuit has a large power. The input power supply VIN generally generates a stable voltage VDD through some power management circuits to supply power to the system. In order to ensure the stability of the VDD voltage, there are many capacitive loads in these power management circuits. When the input power is turned off, the charge accumulated on the capacitive load is difficult to be discharged, resulting in the circuit still having residual charge for a long period of time after the power is turned off. This will bring unstable factors to the circuit system and affect the stability of the circuit system, such as abnormal secondary startup and abnormal power-on and power-off timing. In order to solve the problem of slow discharge of capacitive loads, a discharge circuit is required. The discharge circuit requires that it cannot work during the input power supply is powered on, so as to ensure that VDD is fully charged, and work on the power supply during power off Discharge the remaining charge to ensure the stability of the circuit.

The distributed radar system of this embodiment is provided with such a discharge circuit, so the circuit system has high stability. The discharge circuit for the distance measuring device provided by the embodiment of the present invention will be described below with reference to FIGS. 2 to 3.

2 shows a schematic block diagram of a discharge circuit for a distance measuring device according to an embodiment of the present invention.

The discharge circuit 200 for a distance measuring device provided in this embodiment is used to discharge when the input power VIN is turned off. As shown in FIG. 2, the discharge circuit 200 includes a comparison module 20, a direction detection module 30, a discharge module 40, and an auxiliary Power module 50.

The comparison module 20 is used to compare the voltage of the input power supply VIN and the reference voltage VREF, and generate a comparison signal VOUT1. The comparison module 20 may use various suitable comparison circuits or devices.

Exemplarily, in this embodiment, the comparison module 20 includes a comparator 21, a reference circuit 22, a voltage dividing circuit 23, and a voltage regulator 24.

The comparator 21 is used to compare the voltage of the input power supply VIN with the reference voltage VREF and generate a comparison signal VOUT1. Specifically, in this embodiment, the input terminals of the comparator 21 are connected to the output terminals of the reference circuit 22 and the voltage divider circuit 23 respectively, for comparing the reference voltage VERF generated by the reference circuit 22 and the voltage divider circuit 23 based on the input power supply VIN The size of the generated voltage divider VIN1, and output the comparison signal VOUT1 according to the comparison result.

The reference circuit 22 is used to generate a reference voltage VREF. The reference circuit 22 may adopt various suitable circuit structures or devices. Exemplarily, the reference circuit 22 may use a resistor network voltage divider circuit, a reference power chip, a battery, or the like.

The voltage dividing circuit 23 is provided between the input power supply VIN and the input terminal of the comparator 21, and is used to input the divided voltage VIN1 generated according to the input power supply VIN to the comparator. The voltage dividing circuit 23 can adopt various suitable circuit results, such as a resistance voltage dividing circuit and the like.

The voltage regulator 24 is provided between the input terminal of the comparator 21 and the input power supply VIN or the voltage dividing circuit 23 for stabilizing the voltage input to the comparator 21. Since the input range of the input power supply VIN is relatively wide, the voltage overvoltage of VIN1 or the input comparator 21 can be avoided by the voltage regulator 24 to ensure the safety and stability of the circuit.

The comparison module 20 of the discharge circuit 200 of this embodiment is mainly used to detect the voltage value of the input power supply VIN and determine whether the current voltage value is lower than the reference voltage VERF. Its working principle is: During the discharge process of the input power supply VIN, the voltage of the input power supply VIN will continue to decrease. When the comparator 21 detects that the voltage of the input power supply VIN (in this embodiment, the voltage of the input power supply is represented by the divided voltage VIN1) is lower than the reference voltage VREF, the output voltage of the comparator 21, that is, the level of the comparison signal VOUT1 There will be a transition from low to high, so by detecting the transition of the comparison signal VOUT1 can determine whether the input power VIN is in the power-off state.

As shown in FIG. 3, it shows a waveform relationship between the comparison signal VOU1 of the comparator 21 (that is, the output voltage of the comparator 21) and the divided voltage VIN1 of the input power supply VIN. As shown in FIG. 3, when the voltage VIN1 is lower than VREF, the comparison signal VOUT1 is a high-level signal, and when the voltage VIN1 is greater than or equal to VREF, the comparison signal VOUT1 is a low-level signal. In other words, the comparison signal VOUT1 generated by the comparator 21 has the same level in the time period of t0 to t1 and t4 to t5, and the level of the comparison signal VOUT1 of the comparator 21 in the period of t1 to t4.

As can be seen from FIG. 3, the level of the comparison signal VOUT1 of the comparator 21 may be the same during the input power-up (t0~t1) and power-down (t4-t5) process, if the discharge module 40 is directly determined according to the comparison signal VOUT1 Whether it is on or not, without judging the transition direction of the comparison signal VOUT1, may cause the discharge module 40 to be simultaneously discharged during the input power VIN is powered on, which not only causes additional energy loss, but also slows down the charging of the power supply circuit. However, as described above, the discharge circuit 200 of this embodiment only needs to open the bleeder circuit to discharge the residual charge during the power-off process of the input power supply VIN. Therefore, the discharge circuit 200 of this embodiment is provided with the direction detection module 30.

The direction detection module 30 is used to generate a detection signal VQ indicating whether the input power supply VIN is in a power-down state or a non-power-down state according to the comparison signal VOUT1.

Exemplarily, the direction detection module 30 generates a detection signal VQ indicating that the input power supply VIN is in a power-down state when the comparison signal VOUT1 is a rising edge signal or a falling edge signal. The detection signal VQ includes a high-level signal or a low-level signal. Exemplarily, in this embodiment, the direction detection module 30 is set to be triggered by a rising edge, and the detection signal is a high-level signal, that is, the detection signal VQ of the direction detection module 30 transitions when the comparison signal VOUT1 is a rising edge signal When the comparison signal VOUT1 is other signals, such as a falling edge signal, a high level signal, and a low level signal, the detection signal VQ of the detection module 220 is a low level.

Exemplarily, the direction detection module 30 includes a D flip-flop or a chip with an edge detection function.

It should be understood that although in this embodiment, the direction detection module 30 is configured to be triggered by a rising edge, but in other embodiments, it may also be configured to be triggered by a falling edge, as long as the detection of power-off of the input power supply can be achieved.

The discharge module 40 is used to determine whether to discharge according to the detection signal VQ.

Specifically, the discharge module 40 is turned on to discharge when the detection signal VQ indicates that the input power supply VIN is in a power-down state, and is turned off without discharging when the detection signal VQ indicates that the input power supply VIN is in a non-power-down state. Exemplarily, in this embodiment, when the detection signal VQ is high level, it indicates that the input power supply VIN is in a power-off state, and when the detection signal VQ is low level, it indicates that the input power supply VIN is in a non-power-off state, for example, in a power-on state, In the normal working state, it is powered off but the voltage is still higher than the reference voltage.

Exemplarily, the discharge module 40 includes a resistor R1 and a switching device Q1 connected in series, one end of the resistor R1 is connected to the output terminal (ie, VDD terminal) of the power supply circuit, the other end is connected to the switching device Q1, and one end of the switching device Q1 is connected to the resistor R1 Connect and ground the other end. The switching device Q1 is turned on or off under the control of the detection signal VQ, thereby turning on or off the discharge module 40. Exemplarily, the switching device Q1 includes a MOS transistor, a transistor, an analog switch, or a relay. Exemplarily, in this embodiment, the switching device Q1 is an NMOS transistor.

The auxiliary power module 50 is used to generate the operating voltage VCC of the comparison module 20 and/or the direction detection module 30. For example, the auxiliary power module 50 is used to generate the operating voltage VCC for the reference circuit 22 of the comparison module 20. Exemplarily, the auxiliary power module 50 includes various circuits or modules that can provide a stable voltage, such as a capacitor, a voltage regulator circuit, a power chip, a button battery, or a lithium battery.

The embodiment of the present invention is used in the discharge circuit of the distance measuring device. The direction detection module is used to determine whether the input power is in a power-off state or a non-power-off state, so that it can not work during the power-on process of the input power, ensuring that the power supply circuit is quickly charged. There is no additional energy loss, and work in the process of input power off to discharge the residual charge on the power supply circuit to ensure the stability of the circuit system.

The radar involved in the present invention may be a laser radar, or other radars or ranging devices. In order to better understand the present invention, the principle and structure of the distance measuring device will be exemplarily described below. The distance measuring device may be an electronic device such as a laser radar or a laser distance measuring device. In one embodiment, the distance measuring device is used to sense external environment information, for example, distance information, azimuth information, reflection intensity information, speed information, etc. of the environmental target. In an implementation manner, the distance measuring device can detect the distance between the detecting object and the distance measuring device by measuring the time of light propagation between the distance measuring device and the detection object, that is, Time-of-Flight (TOF). Alternatively, the distance measuring device may also detect the distance between the detected object and the distance measuring device through other techniques, such as a distance measuring method based on phase shift measurement, or a distance measuring method based on frequency shift measurement. There are no restrictions.

For ease of understanding, the following describes the working process of distance measurement in conjunction with the distance measurement device 400 shown in FIG. 5.

As shown in FIG. 4, the distance measuring device 400 may include a transmitting circuit 110, a receiving circuit 120, a sampling circuit 130 and an arithmetic circuit 140.

The transmission circuit 110 may transmit a sequence of light pulses (for example, a sequence of laser pulses). The receiving circuit 120 can receive the optical pulse sequence reflected by the detected object, and photoelectrically convert the optical pulse sequence to obtain an electrical signal, which can be output to the sampling circuit 130 after processing the electrical signal. The sampling circuit 130 may sample the electrical signal to obtain the sampling result. The arithmetic circuit 140 may determine the distance between the distance measuring device 400 and the detected object based on the sampling result of the sampling circuit 130.

Optionally, the distance measuring device 400 may further include a control circuit 150, which may control other circuits, for example, may control the working time of each circuit and/or set parameters for each circuit.

It should be understood that although the distance measuring device shown in FIG. 4 includes a transmitting circuit, a receiving circuit, a sampling circuit, and an arithmetic circuit for emitting a beam of light for detection, the embodiments of the present application are not limited thereto, and the transmitting circuit , The number of any one of the receiving circuit, the sampling circuit, and the arithmetic circuit may also be at least two, for emitting at least two light beams in the same direction or respectively in different directions; wherein, the at least two light paths may be simultaneously The shot may be shot at different times. In one example, the light-emitting chips in the at least two emission circuits are packaged in the same module. For example, each emitting circuit includes a laser emitting chip, and the die in the laser emitting chips in the at least two emitting circuits are packaged together and housed in the same packaging space.

In some implementations, in addition to the circuit shown in FIG. 4, the distance measuring device 400 may further include a scanning module 160 for changing the propagation direction of at least one laser pulse sequence emitted from the transmitting circuit.

Among them, the module including the transmitting circuit 110, the receiving circuit 120, the sampling circuit 130, and the arithmetic circuit 140, or the module including the transmitting circuit 110, the receiving circuit 120, the sampling circuit 130, the arithmetic circuit 140, and the control circuit 150 may be referred to as a measurement Distance module, the distance measuring module may be independent of other modules, for example, a scanning module.

A coaxial optical path may be used in the distance measuring device, that is, the light beam emitted by the distance measuring device and the reflected light beam share at least part of the optical path in the distance measuring device. For example, after at least one laser pulse sequence emitted by the transmitting circuit is emitted by the scanning module to change the propagation direction, the laser pulse sequence reflected by the detection object passes through the scanning module and enters the receiving circuit. Alternatively, the distance measuring device may also adopt an off-axis optical path, that is, the light beam emitted from the distance measuring device and the reflected light beam are respectively transmitted along different optical paths in the distance measuring device. FIG. 5 shows a schematic diagram of an embodiment of the distance measuring device of the present invention using a coaxial optical path.

The distance measuring device 500 includes a distance measuring module 201. The distance measuring module 201 includes a transmitter 203 (which may include the above-mentioned transmitting circuit), a collimating element 204, and a detector 205 (which may include the above-mentioned receiving circuit, sampling circuit, and arithmetic circuit) and Optical path changing element 206. The distance measuring module 201 is used to emit a light beam and receive back light, and convert the back light into an electrical signal. Among them, the transmitter 203 may be used to transmit a sequence of optical pulses. In one embodiment, the transmitter 203 may emit a sequence of laser pulses. Optionally, the laser beam emitted by the transmitter 203 is a narrow-bandwidth beam with a wavelength outside the visible light range. The collimating element 204 is disposed on the exit optical path of the emitter, and is used to collimate the light beam emitted from the emitter 203, and collimate the light beam emitted by the emitter 203 into parallel light to the scanning module. The collimating element is also used to converge at least a part of the return light reflected by the detection object. The collimating element 204 may be a collimating lens or other element capable of collimating the light beam.

In the embodiment shown in FIG. 5, the optical path changing element 206 is used to combine the transmitting optical path and the receiving optical path in the distance measuring device before the collimating element 204, so that the transmitting optical path and the receiving optical path can share the same collimating element, so that the optical path More compact. In some other implementation manners, the transmitter 203 and the detector 205 may respectively use respective collimating elements, and the optical path changing element 206 is disposed on the optical path behind the collimating element.

In the embodiment shown in FIG. 5, since the beam aperture of the light beam emitted by the transmitter 203 is small and the beam aperture of the returned light received by the distance measuring device is large, the light path changing element can use a small-area mirror to convert The transmitting optical path and the receiving optical path are combined. In some other implementations, the light path changing element may also use a reflector with a through hole, where the through hole is used to transmit the outgoing light of the emitter 203, and the reflector is used to reflect the return light to the detector 205. In this way, it is possible to reduce the blocking of the return light by the support of the small mirror in the case of using the small mirror.

In the embodiment shown in FIG. 5, the optical path changing element is offset from the optical axis of the collimating element 204. In some other implementations, the optical path changing element may also be located on the optical axis of the collimating element 204.

The distance measuring device 500 further includes a scanning module 202. The scanning module 202 is placed on the exit optical path of the distance measuring module 201. The scanning module 202 is used to change the transmission direction of the collimated light beam 219 emitted through the collimating element 204 and project it to the external environment, and project the return light to the collimating element 204 . The returned light is converged on the detector 205 via the collimating element 204.

In one embodiment, the scanning module 202 may include at least one optical element for changing the propagation path of the light beam, wherein the optical element may change the propagation path of the light beam by reflecting, refracting, diffracting, etc. the light beam. For example, the scanning module 202 includes a lens, a mirror, a prism, a galvanometer, a grating, a liquid crystal, an optical phased array (Optical Phased Array), or any combination of the above optical elements. In one example, at least part of the optical element is moving, for example, the at least part of the optical element is driven to move by a driving module, and the moving optical element can reflect, refract, or diffract the light beam to different directions at different times. In some embodiments, multiple optical elements of the scanning module 202 may rotate or vibrate about a common axis 209, and each rotating or vibrating optical element is used to continuously change the direction of propagation of the incident light beam. In one embodiment, the multiple optical elements of the scanning module 202 may rotate at different rotation speeds, or vibrate at different speeds. In another embodiment, at least part of the optical elements of the scanning module 202 can rotate at substantially the same rotational speed. In some embodiments, the multiple optical elements of the scanning module may also rotate around different axes. In some embodiments, the multiple optical elements of the scanning module may also rotate in the same direction, or rotate in different directions; or vibrate in the same direction, or vibrate in different directions, which is not limited herein.

In one embodiment, the scanning module 202 includes a first optical element 214 and a driver 216 connected to the first optical element 214. The driver 216 is used to drive the first optical element 214 to rotate about a rotation axis 209 to change the first optical element 214 The direction of the collimated light beam 219. The first optical element 214 projects the collimated light beam 219 to different directions. In one embodiment, the angle between the direction of the collimated light beam 219 after the first optical element changes and the rotation axis 209 changes as the first optical element 214 rotates. In one embodiment, the first optical element 214 includes a pair of opposed non-parallel surfaces through which the collimated light beam 219 passes. In one embodiment, the first optical element 214 includes a prism whose thickness varies along at least one radial direction. In one embodiment, the first optical element 114 includes a wedge-angle prism that aligns the straight beam 219 for refraction.

In one embodiment, the scanning module 202 further includes a second optical element 215 that rotates about a rotation axis 209. The rotation speed of the second optical element 215 is different from the rotation speed of the first optical element 214. The second optical element 215 is used to change the direction of the light beam projected by the first optical element 214. In one embodiment, the second optical element 215 is connected to another driver 217, and the driver 217 drives the second optical element 215 to rotate. The first optical element 214 and the second optical element 215 may be driven by the same or different drivers, so that the first optical element 214 and the second optical element 215 have different rotation speeds and/or rotations, thereby projecting the collimated light beam 219 to the outside space Different directions can scan a larger spatial range. In one embodiment, the controller 218 controls the

drivers

216 and 217 to drive the first optical element 214 and the second optical element 215, respectively. The rotation speeds of the first optical element 214 and the second optical element 215 can be determined according to the area and pattern expected to be scanned in practical applications.

Drives

216 and 217 may include motors or other drives.

In one embodiment, the second optical element 215 includes a pair of opposed non-parallel surfaces through which the light beam passes. In one embodiment, the second optical element 215 includes a prism whose thickness varies along at least one radial direction. In one embodiment, the second optical element 215 includes a wedge angle prism.

In one embodiment, the scanning module 202 further includes a third optical element (not shown) and a driver for driving the third optical element to move. Optionally, the third optical element includes a pair of opposed non-parallel surfaces through which the light beam passes. In one embodiment, the third optical element includes a prism whose thickness varies along at least one radial direction. In one embodiment, the third optical element includes a wedge angle prism. At least two of the first, second and third optical elements rotate at different rotational speeds and/or turns.

The rotation of each optical element in the scanning module 202 can project light into different directions, for example, the directions of the light 211 and 213, so as to scan the space around the distance measuring device 500. When the light 211 projected by the scanning module 202 hits the detection object 210, a part of the light is reflected by the detection object 210 to the distance measuring device 500 in a direction opposite to the projected light 211. The returned light 212 reflected by the detection object 210 passes through the scanning module 202 and enters the collimating element 204.

The detector 205 is placed on the same side of the collimating element 204 as the emitter 203. The detector 205 is used to convert at least part of the returned light passing through the collimating element 204 into an electrical signal.

In one embodiment, each optical element is coated with an antireflection coating. Optionally, the thickness of the antireflection film is equal to or close to the wavelength of the light beam emitted by the emitter 203, which can increase the intensity of the transmitted light beam.

In one embodiment, a filter layer is plated on the surface of an element on the beam propagation path in the distance measuring device, or a filter is provided on the beam propagation path to transmit at least the wavelength band of the beam emitted by the transmitter, Reflect other bands to reduce the noise caused by ambient light to the receiver.

In some embodiments, the transmitter 203 may include a laser diode through which laser pulses in the order of nanoseconds are emitted. Further, the laser pulse receiving time may be determined, for example, by detecting the rising edge time and/or the falling edge time of the electrical signal pulse. In this way, the distance measuring device 500 can use the pulse reception time information and the pulse emission time information to calculate the TOF, thereby determining the distance between the detection object 210 and the distance measuring device 500.

The distance and orientation detected by the distance measuring device 500 can be used for remote sensing, obstacle avoidance, mapping, modeling, navigation, and the like. In one embodiment, the distance measuring device of the embodiment of the present invention can be applied to a movable platform, and the distance measuring device can be installed on the platform body of the movable platform. The mobile platform with a distance measuring device can measure the external environment, for example, measuring the distance between the mobile platform and obstacles for obstacle avoidance and other purposes, and performing two-dimensional or three-dimensional mapping on the external environment. In some embodiments, the movable platform includes at least one of an unmanned aerial vehicle, a car, a remote control car, a robot, and a camera. When the distance measuring device is applied to an unmanned aerial vehicle, the platform body is the fuselage of the unmanned aerial vehicle. When the distance measuring device is applied to an automobile, the platform body is the body of the automobile. The car may be a self-driving car or a semi-automatic car, and no restriction is made here. When the distance measuring device is applied to a remote control car, the platform body is the body of the remote control car. When the distance measuring device is applied to a robot, the platform body is a robot. When the distance measuring device is applied to a camera, the platform body is the camera itself.

In one embodiment, the distributed radar system of the embodiments of the present invention can be applied to a movable platform, so as to perform two-dimensional or three-dimensional mapping of the external environment of the movable platform in multiple orientations. In some embodiments, the movable platform It includes a fuselage, a power system, installed on the fuselage, for powering the movable platform; and a distributed radar system as in this embodiment. The movable platform includes at least one of an unmanned aerial vehicle, a car, or a robot.

The embodiment of the present invention provides a discharge circuit, a distributed radar system and a movable platform of a distance measuring device. The direction detection module determines whether the input power is in a power-off state or a non-power-off state, so that the input power can be powered on It does not work during the process to ensure that the power supply circuit is fully charged and there is no additional energy loss. When the input power supply is powered off, the residual charge on the power supply circuit is discharged to ensure the stability of the circuit system.

Although example embodiments have been described herein with reference to the drawings, it should be understood that the above example embodiments are merely exemplary, and are not intended to limit the scope of the present invention thereto. Those of ordinary skill in the art can make various changes and modifications therein without departing from the scope and spirit of the present invention. All such changes and modifications are intended to be included within the scope of the invention as claimed in the appended claims.

Those of ordinary skill in the art may realize that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in hardware or software depends on the specific application of the technical solution and design constraints. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

In the several embodiments provided in this application, it should be understood that the disclosed device and method may be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a division of logical functions. In actual implementation, there may be other divisions, for example, multiple units or components may be combined or Can be integrated into another device, or some features can be ignored, or not implemented.

The specification provided here explains a lot of specific details. However, it can be understood that the embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this description.

Similarly, it should be understood that in order to streamline the invention and help understand one or more of the various inventive aspects, in describing the exemplary embodiments of the invention, the various features of the invention are sometimes grouped together into a single embodiment, figure , Or in its description. However, the method of the present invention should not be interpreted as reflecting the intention that the claimed invention requires more features than those explicitly recited in each claim. Rather, as reflected in the corresponding claims, its invention lies in that the corresponding technical problems can be solved with less than all the features of a single disclosed embodiment. Therefore, the claims following a specific embodiment are hereby expressly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present invention.

Those skilled in the art will understand that apart from mutually exclusive features, any combination of all the features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all of the methods or devices disclosed in this specification can be used in any combination. Processes or units are combined. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose.

In addition, those skilled in the art can understand that although some of the embodiments described herein include certain features included in other embodiments rather than other features, the combination of features of different embodiments is meant to be within the scope of the present invention And form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

The various component embodiments of the present invention may be implemented in hardware, or implemented in software modules running on one or more processors, or implemented in a combination thereof. Those skilled in the art should understand that, in practice, a microprocessor or a digital signal processor (DSP) may be used to implement some or all functions of some modules according to embodiments of the present invention. The present invention can also be implemented as a device program (for example, a computer program and a computer program product) for performing a part or all of the method described herein. Such a program implementing the present invention may be stored on a computer-readable medium, or may have the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

It should be noted that the above-mentioned embodiments illustrate the present invention rather than limit the present invention, and those skilled in the art can design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs between parentheses should not be constructed as limitations on the claims. The invention can be realized by means of hardware including several different elements and by means of a suitably programmed computer. In the unit claims enumerating several devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third does not indicate any order. These words can be interpreted as names.

The above is only the specific embodiments of the present invention or the description of the specific embodiments, the scope of protection of the present invention is not limited to this, any person skilled in the art in the technical scope of the present invention, can easily Changes or replacements should be included in the protection scope of the present invention. The protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

A discharge circuit for a distance-measuring device, which is used to discharge when the input power supply is powered off, is characterized in that the discharge circuit includes:

A comparison module, used to compare the voltage of the input power supply with the reference voltage and generate a comparison signal;

A direction detection module, configured to generate a detection signal indicating whether the input power is in a power-off state or a non-power-off state according to the comparison signal;

The discharge module is used to determine whether to discharge according to the detection signal.
The discharge circuit according to claim 1, wherein the direction detection module generates a detection signal indicating that the input power is in a power-down state when the comparison signal is a rising edge signal or a falling edge signal.
The discharge circuit according to claim 1, wherein the detection signal comprises a high-level signal or a low-level signal.
The discharge circuit according to claim 1, wherein the discharge module is turned on to discharge when the detection signal indicates that the input power is in a power-off state, and the detection signal indicates that the input power is in It is disconnected without discharging in the non-power-off state.
The discharge circuit according to any one of claims 1 to 4, wherein the comparison module includes:

A reference circuit for generating the reference voltage;

A comparator, the input end of the comparator is connected to the input power supply and the output end of the reference circuit, respectively, and the output end of the comparator outputs the comparison signal.
The discharge circuit according to claim 5, wherein the comparison module further comprises:

A voltage dividing circuit, which is provided between the input power supply and the input terminal of the comparator, and is used to input the divided voltage generated according to the input power supply to the comparator.
The discharge circuit according to claim 6, wherein the comparison module further comprises:

A voltage regulator, which is provided between the input end of the comparator and the input power supply or the voltage dividing circuit, and is used to stabilize the voltage input to the comparator.
The discharge circuit according to claim 1, further comprising:

The auxiliary power module is used to generate the operating voltage of the comparison module and/or the direction detection module.
The discharge circuit according to claim 8, wherein the auxiliary power module includes a capacitor, a voltage regulator circuit, a power chip, a button battery, or a lithium battery.
The discharge circuit according to claim 1, wherein the direction detection module comprises a D flip-flop or a chip with an edge detection function.
The discharge circuit according to claim 1, wherein the discharge module includes a switching device that is turned on or off under the control of the detection signal.
The discharge circuit according to claim 11, wherein the switching device comprises a MOS transistor, a transistor, an analog switch or a relay.
A distributed radar system is characterized by including:

One or more radars;

A power supply circuit that generates an operating voltage for one or more of the radars based on the input power;

The discharge circuit according to any one of claims 1 to 12, wherein the current input terminal of the discharge circuit is connected to the output terminal of the power supply circuit, and the output terminal of the discharge circuit is grounded.
A movable platform is characterized by including:

body;

A power system, installed on the fuselage, is used to provide power to the movable platform;

And the distributed radar system of claim 13.
The movable platform according to claim 14, wherein the movable platform includes a drone, a car, or a robot.