阅读说明：本技术 高动态范围激光雷达 (High dynamic range lidar ) 是由 N.W.哈特 A.L.赖特 于 2020-10-10 设计创作，主要内容包括：提供了用于控制车辆的系统和方法。在一个实施例中,一种方法包括：由控制器接收由于第一激光脉冲或啁啾脉冲而由激光雷达装置的第一检测器检测到的第一返回数据；以及由所述控制器接收由于第二激光脉冲或啁啾脉冲而由所述激光雷达装置的第二检测器检测到的第二返回数据；由所述控制器将所述第一返回数据和所述第二返回数据组合以形成点云；并由控制器基于点云控制车辆。(Systems and methods for controlling a vehicle are provided. In one embodiment, a method comprises: receiving, by the controller, first return data detected by a first detector of the lidar apparatus as a result of the first laser pulse or the chirped pulse; and receiving, by the controller, second return data detected by a second detector of the lidar apparatus as a result of a second laser pulse or chirped pulse; combining, by the controller, the first return data and the second return data to form a point cloud; and controlling the vehicle by the controller based on the point cloud.)

1. A method of controlling a vehicle, the method comprising:

receiving, by the controller, first return data detected by a first detector of the lidar apparatus as a result of the first laser pulse or the chirped pulse;

receiving, by the controller, second return data detected by a second detector of the lidar apparatus as a result of the second laser pulse or the chirped pulse;

combining, by the controller, the first return data and the second return data to form a point cloud; and

controlling, by the controller, the vehicle based on the point cloud.

2. The method of claim 1, further comprising:

initiating, by a controller on the vehicle, a first laser pulse or chirped pulse from the lidar device based on the first power;

initiating, by the controller, a second laser pulse from the lidar device based on the second power; and

wherein the first power is greater than the second power, wherein the first return data is a result of the first laser pulse or chirped pulse, and wherein the second return data is a result of the second laser pulse or chirped pulse.

3. The method of claim 1, wherein combining the first return data and the second return data comprises combining the first return data and the second return data; and determining a distance measurement based on the combination.

4. The method of claim 1, wherein the first laser pulse or chirped pulse is the same laser pulse or chirped pulse as the second laser pulse or chirped pulse.

5. The method of claim 1, wherein the first detector of the lidar apparatus and the second detector of the lidar apparatus are adjacent to one another on the lidar apparatus.

6. The method of claim 1, wherein the first detector of the lidar apparatus and the second detector of the lidar apparatus are spaced apart on the lidar apparatus based on a scan rate.

7. The method of claim 1, wherein the first detector is configured to have a first sensitivity, wherein the second detector is configured to have a second sensitivity, wherein the first sensitivity is greater than the second sensitivity.

8. The method of claim 1, wherein the first return data and the second return data are associated with the same object.

9. The method of claim 1, wherein the first return data comprises a first point measurement, and wherein the second return data comprises a second point measurement.

10. A system for controlling a vehicle, comprising:

a first laser radar device; and

a controller configured to receive, by the processor, first return data detected by a first detector of the lidar apparatus due to the first laser pulse or the chirped pulse, receive second return data detected by a second detector of the lidar apparatus due to the second laser pulse or the chirped pulse, combine the first return data and the second return data to form a point cloud, and control the vehicle based on the point cloud.

Technical Field

The present disclosure relates generally to lidar systems, and more particularly to systems and methods for increasing the range measurement dynamic range of a lidar system for a vehicle.

Background

An autonomous vehicle is a vehicle that is capable of sensing its environment and navigating with little or no user input. Autonomous vehicles use sensing devices such as radar, lidar, image sensors to sense their environment. The autonomous vehicle system also uses information from Global Positioning System (GPS) technology, navigation systems, inter-vehicle communications, vehicle-to-infrastructure technology, and/or drive-by-wire (drive-by-wire) systems to navigate the vehicle.

While autonomous and semi-autonomous vehicles have many potential advantages over conventional vehicles, in some instances, improved operation of the vehicles may be desirable. For example, the sensor system may be characterized based on its different operating distance ranges. Lidar systems provide greater accuracy over greater distances than other sensor systems. However, long-range lidar is more sensitive to elements such as dust, fog, exhaust, etc. in the vicinity of the vehicle due to its increased sensitivity and laser power. Therefore, the close-range accuracy of the long-range lidar is impaired to perform long-range detection.

Accordingly, it is desirable to provide improved systems and methods to increase the range measurement dynamic range of a lidar system. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.

Disclosure of Invention

Systems and methods for controlling a vehicle are provided. In one embodiment, a method comprises: receiving, by a controller, first return data detected by a first detector of a laser radar apparatus as a result of a first laser pulse or chirped pulse (chirp); and receiving, by the controller, second return data detected by a second detector of the lidar apparatus as a result of a second laser pulse or chirped pulse; merging, by the controller, the first return data and the second return data to form a point cloud; and controlling the vehicle by the controller based on the point cloud.

In various embodiments, the method comprises: initiating, by a controller on the vehicle, a first laser pulse of the chirped pulses from the lidar device based on the first power; and initiating, by the controller, a second laser pulse from the lidar device based on the second power; wherein the first power is greater than the second power, wherein the first return data is a result of the first laser pulse or chirped pulse, and wherein the second return data is a result of the second laser pulse or chirped pulse.

In various embodiments, combining the first return data and the second return data includes combining the first return data and the second return data and determining the distance measurement based on the combination.

In various embodiments, the first laser pulse or chirped pulse is the same laser pulse or chirped pulse as the second laser pulse or chirped pulse.

In various embodiments, the first detector of the lidar apparatus and the second detector of the lidar apparatus are adjacent to one another on the lidar apparatus.

In various embodiments, the first detector of the lidar apparatus and the second detector of the lidar apparatus are spaced apart on the lidar apparatus based on the scan rate.

In various embodiments, the first detector is configured to have a first sensitivity, wherein the second detector is configured to have a second sensitivity, wherein the first sensitivity is greater than the second sensitivity.

In various embodiments, the first return data and the second return data are associated with the same object.

In various embodiments, the first return data comprises a first point measurement, and wherein the second return data comprises a second point measurement.

In various embodiments, the first return data comprises a first waveform, and wherein the second return data comprises a second waveform.

In another embodiment, a system for controlling a vehicle includes: a first laser radar device; and a controller configured to receive, by the processor, first return data detected by a first detector of the lidar apparatus due to the first laser pulse or the chirped pulse, receive second return data detected by a second detector of the lidar apparatus due to the second laser pulse or the chirped pulse, combine the first return data and the second return data to form a point cloud, and control the vehicle based on the point cloud.

In various embodiments, the controller is further configured to initiate a first laser pulse of the chirped pulses from the lidar apparatus based on the first power; initiating a second laser pulse from the lidar device based on the second power; wherein the first power is greater than the second power, wherein the first return data is a result of the first laser pulse or chirped pulse, and the second return data is a result of the second laser pulse or chirped pulse.

In various embodiments, the controller is configured to combine the first return data and the second return data by combining the first return data and the second return data and determining a distance measurement based on the combination.

In various embodiments, the first laser pulse or chirped pulse is the same laser pulse or chirped pulse as the second laser pulse or chirped pulse.

In various embodiments, the first detector of the lidar apparatus and the second detector of the lidar apparatus are adjacent to one another on the lidar apparatus.

In various embodiments, the first detector of the lidar apparatus and the second detector of the lidar apparatus are spaced apart on the lidar apparatus based on the scan rate.

In various embodiments, the first detector is configured to have a first sensitivity, wherein the second detector is configured to have a second sensitivity, wherein the first sensitivity is greater than the second sensitivity.

In various embodiments, the first return data and the second return data are associated with the same object.

In various embodiments, the first return data comprises a first point measurement, and wherein the second return data comprises a second point measurement.

In various embodiments, the first return data comprises a first waveform, and wherein the second return data comprises a second waveform.

Drawings

Exemplary embodiments will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:

FIG. 1A is a functional block diagram illustrating an autonomous vehicle having a lidar system, in accordance with various embodiments;

FIG. 1B is a diagram of the vehicle and lidar system of FIG. 1A in accordance with various embodiments;

FIG. 2 is a schematic block diagram of an Autonomous Driving System (ADS) for an autonomous vehicle, in accordance with various embodiments;

FIG. 3 is a data flow diagram of a control module of a lidar system in accordance with various embodiments;

FIG. 4 is a graph illustrating lidar return data in accordance with various embodiments; and

fig. 5 is a flow diagram illustrating a lidar control method in accordance with various embodiments.

Detailed Description

The following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description. As used herein, the term module refers to any hardware, software, firmware, electronic control component, processing logic, and/or processor device, alone or in any combination, including but not limited to: an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that provide the described functionality.

Embodiments of the disclosure may be described herein in terms of functional and/or logical block components and various processing steps. It should be appreciated that such block components may be realized by any number of hardware, software, and/or firmware components configured to perform the specified functions. For example, embodiments of the present disclosure may employ various integrated circuit components, e.g., memory elements, digital signal processing elements, logic elements, look-up tables, or the like, which may carry out a variety of functions under the control of one or more microprocessors or other control devices. In addition, those skilled in the art will recognize that embodiments of the present disclosure may be practiced in conjunction with any number of systems, and that the systems described herein are merely exemplary embodiments of the disclosure.

For the sake of brevity, conventional techniques related to signal processing, data transmission, signaling, control, and other functional aspects of the systems (and the individual operating components of the systems) may not be described in detail herein. Furthermore, the connecting lines shown in the various figures contained herein are intended to represent example functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in an embodiment of the disclosure.

In one or more exemplary embodiments described herein, an autonomously operable vehicle includes a plurality of different devices that generate data representative of a scene or environment in the vicinity of the vehicle from different perspectives. The power of a single sensor or multiple sensors may be varied to improve the range and/or resolution of the sensor data. Additionally, multiple detectors may be implemented to process sensor returns of varying power to improve the range and/or resolution of sensor data. In this regard, the enhanced or augmented data set may then be analyzed and used to determine commands for autonomously operating one or more actuators on the vehicle. In this way, autonomous operation of the vehicle is affected by the enhanced data set.

For example, as described in greater detail below in the context of fig. 1-5, in an exemplary embodiment, a control system, shown generally at 100, is associated with the vehicle 10, in accordance with various embodiments. In general, control system 100 selectively combines lidar return data from at least two lidar pulses or chirped pulses, one generated at high power and one generated at low power, to increase the resolution and/or detection range provided by the final data set.

As shown in FIG. 1A, the vehicle 10 generally includes a chassis 12, a body 14, front wheels 16, and rear wheels 18. The body 14 is disposed on the chassis 12 and substantially surrounds the components of the vehicle 10. The body 14 and chassis 12 may collectively form a frame. The wheels 16-18 are each rotationally coupled to the chassis 12 near a respective corner of the body 14.

In various embodiments, the vehicle 10 is an autonomous vehicle, and the control system 100 is incorporated into the autonomous vehicle 10 (hereinafter referred to as the autonomous vehicle 10). The autonomous vehicle 10 is, for example, a vehicle that is automatically controlled to transport passengers from one location to another. In the illustrated embodiment, the vehicle 10 is depicted as a passenger vehicle, but it should be understood that any other vehicle, including motorcycles, trucks, Sport Utility Vehicles (SUVs), Recreational Vehicles (RVs), boats, airplanes, etc., may also be used. In the exemplary embodiment, autonomous vehicle 10 is a so-called four-level or five-level automation system. The four-level system represents "highly automated", meaning that the autonomous driving system performs (performance) specifically on all aspects of the dynamic driving task, even if the driver does not properly intervene on the demand. A five-level system represents "fully automated," meaning that the autonomous driving system performs at full time on various aspects of the dynamic driving task under all road and environmental conditions that can be managed by the driver. It is understood that in various embodiments, the vehicle may be a non-autonomous vehicle and is not limited to this example.

As shown, the vehicle 10 generally includes: a propulsion system 20, a transmission system 22, a steering system 24, a braking system 26, a sensor system 28, an actuator system 30, at least one data storage device 32, at least one controller 34, and a communication system 36. In various embodiments, propulsion system 20 may include an internal combustion engine, an electric machine such as a traction motor, and/or a fuel cell propulsion system. Transmission system 22 is configured to transfer power from propulsion system 20 to wheels 16-18 according to a selectable speed ratio. According to various embodiments, transmission system 22 may include a stepped ratio automatic transmission, a continuously variable transmission, or other suitable transmission. The braking system 26 is configured to provide braking torque to the wheels 16-18. In various embodiments, the braking system 26 may include friction braking, line braking, a regenerative braking system such as an electric motor, and/or other suitable braking systems. Steering system 24 affects the position of wheels 16-18. Although depicted as including a steering wheel for illustrative purposes, it is contemplated within the scope of the present invention that steering system 24 may not include a steering wheel.

Sensor system 28 includes one or more sensing devices 40a-40n that sense observable conditions of the external environment and/or the internal environment of autonomous vehicle 10. Sensing devices 40a-40n may include, but are not limited to, radar, lidar, global positioning systems, optical cameras, thermal imagers, ultrasonic sensors, and/or other sensors.

In the exemplary embodiment described herein, one or more sensing devices 40a-40n are implemented as lidar devices 40 a. In this regard, the sensing devices 40a-40n may include or incorporate one or more emitters and one or more detectors. The transmitter transmits a light beam, which may be continuous wave, pulsed, or modulated, into the environment of the vehicle 10; and a detector detects reflections of the transmitted beam from the element in the surrounding environment.

In various embodiments, the emitter and detector are suitably configured to horizontally and rotatably scan the environment proximate the vehicle 10 via a scanning device having a particular angular frequency or rotational speed. For example, the emitter and/or transmitter may direct, transmit, emit, and collect light waves using MEM devices, rotating mirrors, micro-motors, Optical Phased Arrays (OPAs), or other solid state scanning methods. As used herein, lidar scanning should be understood to refer to a single turn (revolution) of lidar apparatus 40a, and the scan rate indicates the rate at which lidar apparatus 40a completes the single turn.

In various embodiments, as shown in the exemplary illustration of fig. 1B, lidar device 40a includes at least two detectors 52 (or more) associated with a single emitter 54. A single emitter (E1) is configured to deliver a beam of light at varying power, or to achieve varying power attenuation due to intentional misalignment of the detector. For example, a first detector (D1) is configured to receive and process long range returns reflected from a high power beam (e.g., a pulse of greater than 75W with a width of less than 5ns, or a continuous wave of greater than 100 mW), while a second detector (D2) is configured to receive and process short range returns reflected from a low power beam (e.g., a low power pulse of less than 10W with a width of 5ns, or a continuous wave of less than 10 mW). In another example, the position detector (D1) may be located at the edge where the energy of the gaussian beam profile is less than 1% and 99% is located in the main beam associated with the first detector (D1) so that both returns can be obtained from one pulse or chirped pulse. For the retro-reflector, 1% would provide a large SNR for the second detector (D2) while the first detector (D1) saturates and provides an invalid value, thereby achieving higher range dynamic range on very high reflective objects (e.g., signs) and very low reflective objects (e.g., road surfaces) while one detector cannot.

In various embodiments, the first detector (D1) and the second detector (D2) may be the same type of detector, or may be different types of detectors, including but not limited to PIN Photodiodes (PDs) (least sensitive, short-range, many photons generate 1 electron), Avalanche Photodiodes (APDs) (mid-range), and Single Photon Avalanche Diodes (SPADs) (most sensitive, long-range, 1 photon generates 1 electron). For example, when generating high power pulses for both detectors, a pair comprising SPAD and PD may be implemented. In another example, when a high power pulse is generated for one detector and a low power is generated by alignment or laser control, a pair including SPAD and SPAD may be implemented, or a pair including APD or PD may be implemented.

In various embodiments, the first detector (D1) and the second detector (D2) are positioned adjacent to each other on the scanning device 50. The first detector (D1) and the second detector (D2) may be located on the same scanning device as the emitter (E1) or on a different scanning device. The first detector D1 and the second detector D2 are laterally spaced apart based on the scan rate of the scanning device 50. This interval allows the same object in the environment to be sampled with two consecutive light pulses or chirped pulses, as shown in time steps T1, T2 of fig. 1B. For example, for mechanical spins (spin) and relying on spins to align the detector (D2), the spacing will be related to the spin rate and the pulse/chirp pulse rate. If the pulse rate is 100,000Hz and the spin rate is 10Hz (600rpm), the azimuthal scan from pulse to pulse is 0.036 degrees (360/(100,000/10)), and the detector spacing will be 0.036 degrees.

Referring back to FIG. 1A, actuator system 30 includes one or more actuator devices 42a-42n that control one or more vehicle features such as, but not limited to, propulsion system 20, transmission system 22, steering system 24, and braking system 26. In various embodiments, the vehicle features may also include interior and/or exterior vehicle features such as, but not limited to, door, trunk, and cab features, such as air, music, lighting, etc. (not numbered).

The data storage device 32 stores data for automatically controlling the autonomous vehicle 10. In various embodiments, the data storage device 32 stores a defined map of the navigable environment. In various embodiments, the defined map may be predefined by and obtained from a remote system (described in more detail with respect to fig. 2). For example, the defined map may be assembled by a remote system and communicated (wirelessly and/or in a wired manner) to the autonomous vehicle 10 and stored in the data storage 32. As can be appreciated, the data storage device 32 may be part of the controller 34, separate from the controller 34, or may be part of the controller 34 and part of a separate system.

The communication system 36 is configured to wirelessly communicate with other entities 48, such as, but not limited to, other vehicles ("V2V" communication "), infrastructure (" V2I "communication), remote systems, and/or personal devices (described in more detail with reference to fig. 2). In an exemplary embodiment, the communication system 36 is a wireless communication system configured to communicate via a Wireless Local Area Network (WLAN) using the IEEE 802.11 standard or by using cellular data communication. However, additional or alternative communication methods, such as Dedicated Short Range Communication (DSRC) channels, are also contemplated within the scope of the present disclosure. DSRC channels refer to one-way or two-way short-to-medium range wireless communication channels designed specifically for automotive use, as well as a set of corresponding protocols and standards.

The controller 34 includes at least one processor 44 and a computer-readable storage device or medium 46. The processor 44 may be any custom made or commercially available processor, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), an auxiliary processor among several processors associated with the controller 34, a semiconductor based microprocessor (in the form of a microchip or chip set), a macroprocessor, any combination thereof, or generally any device for executing instructions. For example, the computer-readable storage device or medium 46 may include volatile and non-volatile memory in Read Only Memory (ROM), Random Access Memory (RAM), and Keep Alive Memory (KAM). The KAM is a persistent or non-volatile memory that may be used to store various operating variables when the processor 44 is powered down. The computer-readable storage device or medium 46 may be implemented using any of a number of known memory devices such as PROMs (programmable read Only memory), EPROMs (electrically PROM), EEPROMs (electrically erasable PROM), flash memory, or any other electrical, magnetic, optical, or combination memory device capable of storing data, some of which represent executable instructions, used by the controller 34 in controlling the automotive vehicle 10.

The instructions may comprise one or more separate programs, each of which comprises an ordered listing of executable instructions for implementing logical functions. The instructions, when executed by the processor 44, receive and process signals from the sensor system 28, execute logic, calculations, methods, and/or algorithms for automatically controlling components of the autonomous vehicle 10, and generate control signals to the actuator system 30 to automatically control components of the autonomous vehicle 10 based on the logic, calculations, methods, and/or algorithms. Although only one controller 34 is shown in fig. 1, embodiments of the autonomous vehicle 10 may include any number of controllers 34 that communicate over any suitable communication medium or combination of communication media and cooperate to process sensor signals, execute logic, calculations, methods and/or algorithms, and generate control signals to automatically control features of the autonomous vehicle 10.

In various embodiments, one or more instructions of controller 34 are implemented in control system 100 and, when executed by processor 44, cause processor 44 to perform the methods and systems described in more detail below. In particular, the instructions, when executed by the processor, control the emitter 54 (fig. 1B), the scanning device 50 (fig. 1B), and/or the processed data from the detector 52 (fig. 1B) to combine the low and high transmit power data to form a single distance measurement of the object for use in controlling the vehicle 10.

According to various embodiments, the controller 34 implements an Autonomous Driving System (ADS)70 as shown in fig. 2. That is, suitable software and/or hardware components of the controller 34 (e.g., the processor 44 and the computer-readable storage device 46) are used to provide an autonomous driving system 70 for use in conjunction with the vehicle 10, for example, to automatically control the various actuators 30 on the vehicle 10 to control the acceleration, steering, and braking, respectively, of the vehicle without human intervention.

In various embodiments, the instructions of the autonomous driving system 70 may be organized by function or system. For example, as shown in FIG. 2, the autonomous driving system 70 may include a computer vision system 74, a positioning system 76, a guidance system 78, and a vehicle control system 80. As can be appreciated, in various embodiments, the instructions may be organized into any number of systems (e.g., combined, further partitioned, etc.) as the present disclosure is not limited to the present examples.

In various embodiments, the computer vision system 74 synthesizes and processes the sensor data and predicts the characteristics of object presence, location, classification, and/or path and the environment of the vehicle 10. In various embodiments, the computer vision system 74 may incorporate information from a plurality of sensors including, but not limited to, cameras, lidar, radar, and/or any number of other types of sensors. In various embodiments, the computer vision system 74 implements the control system 100 described herein.

The positioning system 76 processes the vehicle sensor data, as well as other data, to determine the position of the vehicle 10 relative to the environment (e.g., local position relative to a map, accurate position relative to lanes of the road, vehicle heading, speed, etc.). The guidance system 78 processes the sensor data, as well as other data, to determine the path to be followed by the vehicle 10. The vehicle control system 80 generates a control signal for controlling the vehicle 10 according to the determined path.

Referring now to fig. 3 with continued reference to fig. 1A, 1B, and 2, fig. 3 depicts an embodiment of a control module 200 of the control system 100, which may be implemented by or incorporated into the controller 34, the processor 44, and/or the computer vision system 74. In various embodiments, the control module 200 may be implemented as one or more sub-modules. As can be appreciated, in various embodiments, the sub-modules shown and described may be combined and/or further partitioned. Data input to the control module 200 may be received directly from the sensing devices 40a-40n, from other modules (not shown) of the controller 34, and/or from other controllers (not shown). In various embodiments, the control module 200 includes a signal control module 202, a data collection module 204, and a calibration data store 206.

In various embodiments, signal control module 202 generates control signal 208 to control lidar apparatus 40 a. In various embodiments, the signal control module 202 generates at least two control signals. For example, a first control signal 210 is generated by lidar apparatus 40a to initiate a first scan, and a second control signal 212 is generated by lidar apparatus 40a to initiate a second scan.

The timing of the control signals 210, 212 is based on the scan rate. As described above, the scan rate is based on the position of the first detector (D1) relative to the second detector (D2). For example, the scan rate is set such that the same object can be sampled by two consecutive pulses. In various embodiments, the signal control module 202 determines the scan rate based on calibration information stored in the calibration data store 206.

In various embodiments, the signal control module 202 generates the control signals 210, 212 based on the desired power. For example, a first control signal 214 is generated by the lidar device 40a to control the pulse based on a first high power (e.g., power in a first range), and a second control signal 216 is generated by the lidar device to control the pulse based on a second low power (e.g., power in a second range) or based on the first high power (e.g., based on detector implementation and spacing). The first control signal 214 corresponds to the first control signal 210 and the second control signal 216 corresponds to the second control signal 212 such that the return signal from the first scan is observed by the first detector D1 (optimized for long range performance) and the return signal from the second scan is observed by the second detector D2 (optimized for short range performance). In various embodiments, the signal control module 202 determines the power (e.g., low or high) based on calibration information stored in the calibration data store 206.

In various embodiments, the signal control module generates control data 218 indicative of the position, timing, and signal values associated with the control signals 210, 212.

Data processing module 204 receives control data 218, lidar return data 220 as a result of the first signal, and lidar return data 222 as a result of the second signal, and generates point cloud data 224 based thereon. In various embodiments, data processing module 204 generates point cloud data 224 by combining each point and/or waveform of lidar return data 220, 222, thereby improving range and resolution.

For example, as shown in FIG. 4, the graph shows distance along the x-axis and intensity along the y-axis. The long-range waveform 80 and the short-range waveform 82 are combined to form a combined waveform 84 for the short-range distance. The combined waveform eliminates short range noise of the long range waveform. The combined waveform is used to generate point cloud data 224. Other systems may then use the point cloud data 224 for further analysis and control of the vehicle 10.

Referring now to fig. 5, with continued reference to fig. 1-4, flowcharts illustrate various embodiments of a process 300 according to the present disclosure, which process 300 may be embedded within the controller 34 in the control system 100 of fig. 1 supporting the ADS 70 and the control module 200 of fig. 3. As can be appreciated in light of the present disclosure, the order of operations within the method is not limited to being performed in the order shown in fig. 5, but may be performed in one or more varying orders as applicable and in accordance with the present disclosure. In various embodiments, the process 300 may be scheduled to run based on one or more predetermined events and/or may run continuously during operation of the vehicle 10.

In one example, the method may begin at 305. At 310, control signal 210 is generated to control lidar apparatus 40a according to the first scan rate and power. At 320, the lidar waveform with high transmitted power is collected by a first detector D1 with alignment optimized for long range performance. Optionally, at 330, control signal 212 is generated to control lidar apparatus 40a according to the second scan rate and power (e.g., when implementing low-power pulses or chirped pulses). At 340, the lidar waveform with low transmit power is collected by a second detector D2 with alignment optimized for short range performance.

Thereafter, at 350, the high power long range waveform and the low power short range waveform are combined into a single lidar point, e.g., as discussed above with respect to fig. 4. At 360, individual lidar points are assembled into a lidar point cloud for use in controlling the vehicle 10. Thereafter, the method may end at 370.

While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the disclosure in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing the exemplary embodiment or exemplary embodiments. It should be understood that various changes can be made in the function and arrangement of elements without departing from the scope of the disclosure as set forth in the appended claims and the legal equivalents thereof.