CN114585946A

CN114585946A - Laser ranging device, laser ranging method and movable platform

Info

Publication number: CN114585946A
Application number: CN202080070617.4A
Authority: CN
Inventors: 罗一俊
Original assignee: SZ DJI Technology Co Ltd
Current assignee: SZ DJI Technology Co Ltd
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2022-06-03
Also published as: WO2022141049A1

Abstract

A laser ranging apparatus (100), a laser ranging method and a movable platform, the laser ranging apparatus (100) comprising: a transmitting circuit (110) for transmitting laser pulses; a receiving circuit (120) for receiving at least part of the return light pulse reflected by the object to be measured and converting it into an electrical signal; a sampling circuit (130) for sampling the electrical signal to obtain a sampling result; an arithmetic circuit (140) for obtaining point cloud data based on the sampling result; and the webpage server (150) is used for carrying out visualization processing on the point cloud data to obtain point cloud image data and outputting the point cloud image data to external equipment through a webpage protocol. The laser ranging device carries out visual processing on the point cloud data based on the webpage server, outputs the point cloud image data to external equipment through a webpage protocol, and can browse the point cloud image through the external equipment.

Description

Laser ranging device, laser ranging method and movable platform

Technical Field

The embodiment of the invention relates to the technical field of distance measurement, in particular to a laser distance measurement device, a laser distance measurement method and a movable platform.

Background

The laser ranging device actively transmits and receives laser pulses and calculates the distance information of the detected object according to the information such as the flight time difference or the phase difference of laser echo signals. The laser ranging device is used as an advanced sensing device capable of sensing three-dimensional information of the environment, and is widely applied to the fields of various intelligent robots and automatic driving in recent years.

The existing laser ranging device generally sends collected point cloud data to an upper computer for point cloud display. When the upper computer is used for point cloud display, the normal operation of the upper computer depends on various software and hardware related factors such as hardware configuration, operating system type/version, firewall configuration and the like of the computer; moreover, the same type of upper computer software cannot be used across an operating system platform and a hardware architecture platform, and further cannot be run on some embedded platforms.

Disclosure of Invention

In this summary, concepts in a simplified form are introduced that are further described in the detailed description. This summary of the invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In view of the defects in the prior art, a first aspect of the embodiments of the present invention provides a laser ranging apparatus, including:

a transmitting circuit for transmitting laser pulses;

the receiving circuit is used for receiving at least part of return light pulses reflected by the measured object by the laser pulses and converting the return light pulses into electric signals;

the sampling circuit is used for sampling the electric signal to obtain a sampling result;

the arithmetic circuit is used for obtaining point cloud data based on the sampling result;

and the webpage server is used for carrying out visualization processing on the point cloud data to obtain point cloud image data and outputting the point cloud image data to external equipment through a webpage protocol.

A second aspect of the embodiments of the present invention provides a laser ranging method, which is used for a laser ranging device, where the laser ranging device includes a web server, and the laser ranging method includes:

emitting laser pulses;

receiving at least part of return light pulses of the laser pulses reflected by the measured object and converting the return light pulses into electric signals;

sampling the electrical signal to obtain a sampling result;

obtaining point cloud data based on the sampling result;

and the webpage server performs visualization processing on the point cloud data to obtain point cloud image data, and outputs the point cloud image data to external equipment through a webpage protocol.

A third aspect of the embodiments of the present invention provides a movable platform, where the movable platform includes the laser distance measuring device and a movable platform body, and the laser distance measuring device is disposed on the movable platform body.

The laser ranging device, the laser ranging method and the movable platform provided by the embodiment of the invention perform visual processing on the point cloud data based on the webpage server, output the point cloud image data to external equipment through a webpage protocol, and browse the point cloud image through the external equipment.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor.

FIG. 1 is a schematic block diagram of a laser ranging device of an embodiment of the present invention;

FIG. 2 is a schematic diagram of an embodiment of a laser ranging device using coaxial optical paths according to embodiments of the present invention;

FIG. 3 is a schematic diagram of a scanning pattern of a laser ranging device according to an embodiment of the present invention;

FIG. 4 illustrates a data interaction framework of a laser ranging device and an external device according to one embodiment of the present invention;

FIG. 5 illustrates a schematic diagram of a coordinate system transformation of point cloud data based on pose data measured by an inertial measurement unit, according to one embodiment of the invention;

FIG. 6 is a schematic flow diagram of a laser ranging method according to one embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. It is to be understood that the described embodiments are merely a subset of embodiments of the invention and not all embodiments of the invention, with the understanding that the invention is not limited to the example embodiments described herein. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the invention described herein without inventive step, shall fall within the scope of protection of the invention.

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.

It is to be understood that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

In order to provide a thorough understanding of the present invention, a detailed structure will be set forth in the following description in order to explain the present invention. Alternative embodiments of the invention are described in detail below, however, the invention may be practiced in other embodiments that depart from these specific details.

Next, a laser ranging apparatus 100 according to an embodiment of the present application is first described with reference to fig. 1. In one embodiment, the laser ranging device is used to sense external environmental information, such as distance information, orientation information, reflected intensity information, velocity information, etc. of environmental targets. The laser ranging apparatus may detect a distance from the probe to the laser ranging apparatus through a Time-of-Flight (TOF) that is a Time of light propagation between the laser ranging apparatus and the probe.

As shown in fig. 1, the laser ranging apparatus 100 may include a transmitting circuit 110, a receiving circuit 120, a sampling circuit 130, an arithmetic circuit 140, and a web server 150.

Wherein the transmit circuit 110 is configured to transmit laser pulses. The receiving circuit 120 is used for receiving at least a part of the return light pulse reflected by the object to be measured from the laser pulse emitted by the emitting circuit 110 and converting it into an electrical signal. The sampling circuit 130 is used for sampling the electrical signal to obtain a sampling result. The arithmetic circuit 140 is used for obtaining point cloud data based on the sampling result. The web server 150 is configured to perform visualization processing on the point cloud data to obtain point cloud image data, and output the point cloud image data to an external device through a web protocol.

Optionally, the laser distance measuring device 100 may further include a control circuit, and the control circuit may implement control of other circuits, for example, may control an operating time of each circuit and/or perform parameter setting on each circuit, and the like.

It should be understood that, although the laser distance measuring device shown in fig. 1 includes a transmitting circuit, a receiving circuit, a sampling circuit and an arithmetic circuit for emitting a light beam to detect, the embodiment of the present application is not limited thereto, and the number of any one of the transmitting circuit, the receiving circuit, the sampling circuit and the arithmetic circuit may be at least two, and the at least two light beams are emitted in the same direction or in different directions respectively; the at least two light paths may be emitted simultaneously or at different times. In one example, the light emitting chips in the at least two transmitting circuits are packaged in the same module. For example, each transmitting circuit comprises a laser emitting chip, and die of the laser emitting chips in the at least two transmitting circuits are packaged together and accommodated in the same packaging space.

In some implementations, in addition to the circuit shown in fig. 1, the laser ranging apparatus 100 may further include a scanning module, configured to change the propagation direction of at least one laser pulse sequence emitted from the emitting circuit 110. The module including the transmitting circuit 110, the receiving circuit 120, the sampling circuit 130 and the operation circuit 140 may be referred to as a measurement module, which may be independent of other modules, such as the web server 150 and the scanning module.

The main function of the Web Server 150(Web Server) is to provide an information browsing service on the Web. When an external device connects to the web server 150 (via a browser) and requests a file, the web server 150 will process the request and feed the file back to the requesting browser and inform the browser of the file type. The web server 150 communicates information with the browser of the external device using a web protocol (e.g., hypertext transfer protocol, HTTP). In the embodiment of the present invention, the web server 150 is configured to perform visualization processing on the point cloud data and generate point cloud image data supported by a web page, so that the laser ranging apparatus 100 can obtain the point cloud image data by itself without sending the point cloud data to an upper computer for visualization processing. When the external device requests the point cloud image data, the web server 150 can feed the point cloud image data back to the browser of the external device through the web protocol, so that a user can browse the point cloud image on the browser of the external device without depending on an upper computer.

Since the point cloud visualization processing of the embodiment of the present invention is implemented by the web server 150, the external device itself does not need to perform visualization processing on the point cloud data, and thus requirements on various software and hardware related conditions such as hardware configuration of the external device, the type and version of the operating system, and firewall configuration are low. Moreover, since the laser ranging apparatus 100 and the external device perform data transmission via the web protocol, it is not necessary to close the firewall and open an additional port. The laser ranging device 100 according to the embodiment of the present invention can browse the point cloud image only based on the external device having the network communication function and the browser supporting function, and can be easily adapted to external devices of various types of devices, such as a computer, a mobile phone, an embedded device, and the like.

In addition, each point in the point cloud data includes three-dimensional coordinate information, and may further include reflection intensity information, color information, echo frequency information, and the like, so that the data volume of the point cloud data is generally large. The point cloud image data includes pixel information, and thus the data amount of the point cloud image data is relatively small. The web server 150 of the embodiment of the invention only needs to transmit the point cloud image data, so that the data transmission speed is greatly improved, and the limitation of the memory of the external equipment is avoided.

For example, when the laser ranging apparatus 100 is close to the external device, the external device and the web server 150 may be connected through a local area network. When the laser ranging apparatus 100 is far away from the external device, the external device and the web server 150 may be connected through a wide area network.

In some embodiments, the web server 150 is further configured to receive an operation instruction for the point cloud image data from the external device through the web protocol, and process the point cloud image data according to the operation instruction. The operation instruction for the point cloud image data includes, but is not limited to, dragging, zooming, clipping, and the like.

The web server 150 of the embodiment of the present invention is further configured to implement a function of point cloud storage. A user can input a storage instruction of point cloud data at a browser end of an external device, wherein the storage instruction comprises time parameters for starting and ending recording of the point cloud data of a specific time period; the web server 150 is further configured to receive a storage instruction for the point cloud data from the external device through a web protocol, and store the point cloud data within a specified time to the local of the laser distance measuring apparatus 100 according to the storage instruction. The web server 150 may store the point cloud data in a memory inside the web server 150, or may store the point cloud data in another memory locally disposed in the laser ranging apparatus. Therefore, the point cloud storage function is realized based on the web server 150, so that the user can control the laser ranging device 100 to sample at the external equipment end, and the operation convenience of the laser ranging device 100 is greatly improved.

Referring to fig. 4, a data interaction framework of the laser ranging device and the external device according to one embodiment of the present invention is shown. The laser ranging device 100 performs data interaction with external equipment through a web protocol: the external device sends a control instruction to the web server 150 through the web protocol, and the web server 150 sends point cloud image data to the external device through the web protocol. The control instruction sent by the external device includes, but is not limited to, a storage instruction for point cloud data, a browsing instruction for point cloud images, an operation instruction for point cloud image data, and the like. The user can input various commands through the input device of the external device.

Illustratively, a browser of the external device may display the point cloud image based on WebGL. WebGL (Web Graphics Library) is a 3D mapping protocol that can provide hardware 3D accelerated rendering for a rendering engine, thereby enabling a browser to more smoothly display a 3D point cloud image. Based on WebGL, the point cloud image can be browsed directly based on a browser without rendering plug-ins.

In addition, in the past, when a point cloud image is displayed based on an upper computer, the upper computer is limited to only acquiring point cloud data and generating the point cloud image according to the point cloud data, and as the point cloud data acquired by the laser ranging device is the point cloud data under the coordinate system of the laser ranging device, the visual angle of the laser ranging device is displayed when the point cloud image is observed. In the using process, if the laser ranging device is not installed horizontally with the bottom surface facing downwards, and when the surrounding environment features are not obvious, a user cannot intuitively directly correspond the point cloud image with the surrounding real world environment. In order to view the point cloud image in the world coordinate system, a user needs to manually drag the point cloud image in the upper computer, so that the direction of the point cloud image is consistent with that of the point cloud image in the real environment, automatic adaptation cannot be realized, and the operation is complex.

To this end, the laser ranging apparatus 100 according to an embodiment of the present invention further includes an inertial measurement unit for measuring the attitude 100 of the laser ranging apparatus in real time to obtain attitude data time-aligned with the point cloud data. When the point cloud data and the attitude data are fused and then displayed, the generated point cloud image can always correspond to the real environment no matter the laser ranging device is in any attitude.

Illustratively, the inertial measurement unit includes an accelerometer and a gyroscope. The gyroscope can be a three-axis gyroscope, and the movement state of the laser ranging device in a three-dimensional space is judged through measuring the included angle between the vertical axis of the gyroscope rotor in the three-dimensional coordinate system and the laser ranging device, calculating the angular speed and the included angle and the angular speed. The accelerometer can sense the acceleration in any direction, and the magnitude and the direction of the acceleration in the axial direction are obtained by measuring the stress condition of the component in the axial direction. Based on the linear acceleration and the angular velocity measured by the accelerometer and the gyroscope, the attitude information of the laser ranging apparatus 100 at each time can be obtained by integration.

When the laser ranging apparatus 100 includes the inertia measurement unit, the attitude data of the laser ranging apparatus 100 itself can be measured without an external inertia measurement unit, so that the coordinate system of the point cloud data is converted according to the attitude data. On the contrary, if an external inertia measurement unit is adopted, and the attitude calibration is performed between the inertia measurement unit and the carrier and then between the inertia measurement unit and the laser ranging device, the attitude calibration between the inertia measurement unit and the laser ranging device has deviation, so that the point cloud image is inclined.

Since the laser distance measuring device 100 of the embodiment of the present invention may generate the point cloud image data based on the web server 150, in an embodiment, the coordinate system conversion of the point cloud data may be implemented inside the laser distance measuring device 100, that is, the computing circuit 140 is further configured to convert the point cloud data in the coordinate system of the laser distance measuring device into the world coordinate system according to the pose data, so as to obtain the point cloud data in the world coordinate system. The web server 150 is further configured to perform visualization processing on the point cloud data in the world coordinate system to obtain point cloud image data in the world coordinate system. The web server 150 is further configured to output point cloud image data in a world coordinate system to an external device through a web protocol.

Therefore, after the point cloud data are converted into the world coordinate system, the point cloud image obtained according to the point cloud data in the world coordinate system is equivalent to the point cloud image acquired by the laser ranging device in the standard posture, and therefore a user can directly correspond the point cloud image to the surrounding real world environment.

Since the pose of the laser ranging apparatus 100 is not fixed, after obtaining the pose information collected by the inertial measurement unit, time alignment between the pose information and the point cloud data is also included. For example, according to the attitude data time-aligned with the point cloud data, a coordinate transformation matrix for transforming the point cloud data from the laser distance measuring device coordinate system to the world coordinate can be obtained, and the point cloud data under the laser distance measuring device coordinate system can be transformed to the world coordinate system by multiplying the coordinate transformation matrix with the point cloud data under the laser distance measuring device coordinate system.

Referring to fig. 5, in some embodiments, the web server 150 may generate point cloud image data in the laser ranging device coordinate system based on the point cloud data in the laser ranging device coordinate system and may generate point cloud image data in the world coordinate system based on the point cloud data in the world coordinate system. The user may input a selection instruction for the point cloud coordinate system in a browser of the external device, the web server 150 receives the selection instruction for the point cloud coordinate system through the web protocol, and selectively outputs point cloud image data in a world coordinate system or point cloud image data in a laser ranging apparatus coordinate system to the external device according to the selection instruction. When the external equipment requests point cloud image data under the coordinate system of the laser ranging device, the webpage server 150 sends the point cloud image data under the coordinate system of the laser ranging device; when the external device requests point cloud image data in the world coordinate system, the web server 150 transmits the point cloud image data in the world coordinate system. Therefore, online switching of the point cloud coordinate system can be realized.

The web server 150 may generate point cloud image data in a corresponding coordinate system after receiving a selection instruction of the point cloud coordinate system. Alternatively, the web server 150 may generate point cloud image data in two coordinate systems, and after receiving a selection instruction for the point cloud coordinate system, send the point cloud image data in the corresponding coordinate system. Of course, the web server 150 may also default to sending the point cloud image data in the world coordinate system.

In some embodiments, the laser distance measuring apparatus 100 further includes an upper computer port, that is, the laser distance measuring apparatus 100 may output the point cloud image data to the external device through a web protocol, and may also output the point cloud data to the upper computer through a conventional upper computer port, and perform visualization processing on the point cloud data by the upper computer to obtain the point cloud image. The host computer can connect a plurality of laser rangefinder 100, carries out the interaction of order and some cloud data with a plurality of laser rangefinder 100 simultaneously to obtain the panorama information of surrounding environment. The laser ranging device 100 and the upper computer can keep long connection through a heartbeat mechanism, and commands and point cloud data can be interacted between the upper computer and the laser ranging device 100 based on the long connection.

In one embodiment, the laser distance measuring device 100 may output the point cloud data under the coordinate system of the laser distance measuring device and the pose data to the upper computer through a port of the upper computer, so that the upper computer converts the point cloud data under the coordinate system of the laser distance measuring device into the world coordinate system according to the pose data to obtain the point cloud data under the world coordinate system. The upper computer displays the point cloud data and the attitude data after fusing the point cloud data and the attitude data, so that the point cloud image can always correspond to the real environment no matter the laser ranging device is in any attitude.

In another embodiment, the coordinate system conversion of the point cloud data may be implemented by the laser ranging device 100, that is, the laser ranging device 100 converts the point cloud data in the coordinate system of the laser ranging device into the world coordinate system according to the pose data to obtain the point cloud data in the world coordinate system; then, the laser ranging device 100 may output the point cloud data under the world coordinate system to the upper computer through the upper computer port, so that the upper computer may perform visualization processing on the point cloud data under the world coordinate system to obtain point cloud image data under the world coordinate system. Therefore, the laser ranging device 100 does not need to transmit attitude data to an upper computer, and data transmission amount is reduced.

For example, a world coordinate system and a laser distance measuring device coordinate system option can be set in the upper computer, and a user can manually switch the coordinate system of the point cloud image. The laser ranging device 100 is further configured to receive a selection instruction for the point cloud coordinate system through the host interface, and selectively output point cloud data in the world coordinate system or output point cloud data in the laser ranging device coordinate system to the host according to the selection instruction. Specifically, when a selection instruction for the coordinate system of the laser ranging device is received through the port of the upper computer, the laser ranging device 100 outputs point cloud data under the coordinate system of the laser ranging device; when a selection instruction for the world coordinate system is received through the upper computer port, the laser ranging device 100 outputs point cloud data in the world coordinate system, or outputs attitude data and point cloud data in the ranging device coordinate system, so that the upper computer performs coordinate system conversion on the point cloud data. Therefore, online switching of the point cloud coordinate system can be realized through the upper computer.

Of course, in other embodiments, the laser distance measuring device 100 may also default to send the point cloud data and the pose data in the coordinate system of the laser distance measuring device to the upper computer, and the upper computer selectively generates the point cloud image data in the coordinate system of the laser distance measuring device or the point cloud image data in the world coordinate system according to the selection instruction of the point cloud coordinate system input by the user, so as to implement switching of the point cloud image coordinate system.

As described above, the laser ranging apparatus 100 may further include a scanning module, configured to change the propagation direction of at least one laser pulse sequence emitted from the transmitting circuit 110. Alternatively, the laser distance measuring device 100 may adopt a coaxial optical path, that is, the light beam emitted from the laser distance measuring device 100 and the reflected light beam share at least part of the optical path in the laser distance measuring device 100. For example, at least one laser pulse sequence emitted from the emitting circuit 110 changes the propagation direction through the scanning module and then emits, and the laser pulse sequence reflected by the probe passes through the scanning module and then enters the receiving circuit 120. Alternatively, the laser distance measuring device 100 may also adopt an off-axis optical path, that is, the light beam emitted from the laser distance measuring device 100 and the reflected light beam are transmitted along different optical paths in the laser distance measuring device. Fig. 2 shows a schematic diagram of a laser distance measuring device using coaxial optical paths according to an embodiment of the present invention.

As shown in fig. 2, the laser ranging device 200 includes a ranging module 210, the ranging module 210 including an emitter 203 (which may include the above-described emitting circuitry), a collimating element 204, a detector 205 (which may include the above-described receiving circuitry, sampling circuitry, and arithmetic circuitry), and a path-altering element 206. The distance measuring module 210 is configured to emit a light beam, receive return light, and convert the return light into an electrical signal. Wherein the emitter 203 may be configured to emit a sequence of light pulses. In one embodiment, the transmitter 203 may emit a sequence of laser pulses. Optionally, the laser beam emitted by the emitter 203 is a narrow bandwidth beam having a wavelength outside the visible range. The collimating element 204 is disposed on an emitting light path of the emitter, and is configured to collimate the light beam emitted from the emitter 203, and collimate the light beam emitted from the emitter 203 into parallel light to be emitted to the scanning module. The collimating element is also for converging at least a portion of the return light reflected by the detector. The collimating element 204 may be a collimating lens or other element capable of collimating a light beam.

In the embodiment shown in fig. 2, the transmitting optical path and the receiving optical path in the laser ranging apparatus are combined before the collimating element 204 by the optical path changing element 206, so that the transmitting optical path and the receiving optical path can share the same collimating element, and the optical path is more compact. In other implementations, the emitter 203 and the detector 205 may use respective collimating elements, and the optical path changing element 206 may be disposed in the optical path after the collimating elements.

In the embodiment shown in fig. 2, since the beam aperture of the beam emitted from the emitter 203 is small and the beam aperture of the return light received by the laser ranging device is large, the optical path changing element can adopt a small-area mirror to combine the emission optical path and the reception optical path. In other implementations, the optical path changing element may also be a mirror with a through hole, wherein the through hole is used for transmitting the outgoing light from the emitter 203, and the mirror is used for reflecting the return light to the detector 205. Therefore, the shielding of the bracket of the small reflector to the return light can be reduced in the case of adopting the small reflector.

In the embodiment shown in fig. 2, the optical path altering component is offset from the optical axis of the collimating component 204. In other implementations, the optical path altering element may also be located on the optical axis of the collimating element 204.

The laser ranging device 200 also includes a scanning module 202. The scanning module 202 is disposed on the emitting light path of the distance measuring module 210, and the scanning module 202 is configured to change the transmission direction of the collimated light beam 219 emitted by the collimating element 204, project the collimated light beam to the external environment, and project the return light beam to the collimating element 204. The return light is converged by the collimating element 104 onto the detector 205.

In one embodiment, the scanning module 202 may include at least one optical element for altering the propagation path of the light beam, wherein the optical element may alter the propagation path of the light beam by reflecting, refracting, diffracting, etc., the light beam. For example, the scanning module 202 includes a lens, mirror, prism, grating, liquid crystal, Optical Phased Array (Optical Phased Array), or any combination of the above Optical elements. In one example, at least a portion of the optical element is moved, for example, by a driving module, and the moved 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 oscillate about a common axis 209, with each rotating or oscillating optical element serving to constantly change the direction of propagation of an incident beam. In one embodiment, the multiple optical elements of the scanning module 202 may rotate at different rotational speeds or oscillate at different speeds. In another embodiment, at least some of the optical elements of the scanning module 202 may rotate at substantially the same rotational speed. In some embodiments, the multiple optical elements of the scanning module may also be rotated about different axes. In some embodiments, the multiple optical elements of the scanning module may also rotate in the same direction, or in different directions; or in the same direction, or in different directions, without limitation.

In one embodiment, the scanning module 202 includes a first optical element 214 and a driver 216 coupled to the first optical element 214, the driver 216 configured to drive the first optical element 214 to rotate about the rotation axis 209, such that the first optical element 214 redirects the collimated light beam 219. The first optical element 214 projects the collimated beam 219 into different directions. In one embodiment, the angle between the direction of the collimated beam 219 after it is altered by the first optical element and the axis of rotation 209 changes as the first optical element 214 is rotated. In one embodiment, the first optical element 214 includes a pair of opposing non-parallel surfaces through which the collimated light beam 219 passes. In one embodiment, the first optical element 214 includes a prism having a thickness that varies along at least one radial direction. In one embodiment, the first optical element 214 comprises a wedge angle prism that refracts the collimated beam 219.

In one embodiment, the scanning module 202 further comprises a second optical element 215, the second optical element 215 rotating around a rotation axis 209, the rotation speed of the second optical element 215 being 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 coupled 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, such that the first optical element 214 and the second optical element 215 rotate at different speeds and/or turns, thereby projecting the collimated light beam 219 into different directions in the ambient space, which may 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 speed of the first optical element 214 and the second optical element 215 can be determined according to the region and the pattern expected to be scanned in the actual application. The

drives

216 and 217 may include motors or other drives.

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

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

Rotation of the optical elements in the scanning module 202 may project light into different directions, such as light 211 and light 213, thus scanning the space around the laser ranging device 200. Fig. 3 is a schematic diagram of a scanning pattern of the laser ranging device 200, as shown in fig. 3. It will be appreciated that as the speed of the optical elements within the scanning module changes, the scanning pattern will also change.

When the light 211 projected by the scanning module 202 hits the object 201, a part of the light is reflected by the object 201 to the laser ranging device 200 in a direction opposite to the projected light 211. The return light 212 reflected by the object 201 passes through the scanning module 202 and then enters the collimating element 204.

The detector 205 is placed on the same side of the collimating element 204 as the emitter 203, and the detector 205 is used to convert at least part of the return 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 coated on a surface of a component in the laser ranging device located on the light beam propagation path, or a filter is arranged on the light beam propagation path and used for transmitting at least a wave band in which the light beam emitted by the emitter is located and reflecting other wave bands, so that noise brought by ambient light to the receiver is reduced.

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 reception 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 manner, the laser ranging apparatus 200 may calculate TOF using the pulse reception time information and the pulse emission time information, thereby determining the distance of the probe 201 from the laser ranging apparatus 200.

The distance and orientation detected by laser rangefinder 200 may be used for remote sensing, obstacle avoidance, mapping, modeling, navigation, and the like. In one embodiment, the laser ranging device of the embodiment of the present invention may be applied to a movable platform, and the laser ranging device may be mounted on a movable platform body of the movable platform. The movable platform with the laser ranging device can measure the external environment, for example, the distance between the movable platform and an obstacle is measured for the purpose of avoiding the obstacle, and the two-dimensional or three-dimensional mapping is carried out on the external environment.

In summary, the laser ranging apparatus according to the embodiment of the present invention performs visualization processing on the point cloud data based on the web server, outputs the point cloud image data to the external device through the web protocol, and can browse the point cloud image through the external device.

Another aspect of an embodiment of the present invention provides a laser ranging method for a laser ranging device, where the laser ranging device includes a web server. Next, a laser ranging method according to an embodiment of the present invention will be described with reference to fig. 6. Fig. 6 is a schematic flow chart of a laser ranging method 600 of an embodiment of the present invention. The laser ranging method 600 may be implemented by the laser ranging apparatus described in any of the above embodiments. Only the main steps of the laser ranging method 600 will be described below, and some of the above detailed details are omitted.

As shown in fig. 6, a laser ranging method 600 according to an embodiment of the present invention includes the following steps:

in step S610, a laser pulse is emitted;

in step S620, at least a part of the return light pulse reflected by the object to be measured is received and converted into an electrical signal;

in step S630, sampling the electrical signal to obtain a sampling result;

in step S640, point cloud data is obtained based on the sampling result;

in step S650, the web server performs visualization processing on the point cloud data to obtain point cloud image data, and outputs the point cloud image data to an external device through a web protocol.

In one embodiment, the laser ranging method 600 further comprises: the webpage server receives a storage instruction of the point cloud data from the external equipment through a webpage protocol, and stores the point cloud data in the appointed time to the local laser ranging device according to the storage instruction.

In one embodiment, the laser ranging method 600 further comprises: the webpage server receives an operation instruction of the point cloud image data from the external equipment through a webpage protocol, and processes the point cloud image data according to the operation instruction.

In one embodiment, the laser ranging apparatus further comprises an inertial measurement unit, and the laser ranging method 600 further comprises: and measuring the attitude of the laser ranging device in real time through the inertial measurement unit to obtain attitude data aligned with the point cloud data in time.

Further, the laser ranging method 600 further includes: and converting the point cloud data under the coordinate system of the laser ranging device into a world coordinate system according to the attitude data to obtain the point cloud data under the world coordinate system.

Further, the laser ranging method 600 further includes: and the webpage server performs visualization processing on the point cloud data under the world coordinate system to obtain point cloud image data under the world coordinate system. Further, the laser ranging method 600 further includes: and the webpage server outputs point cloud image data under the world coordinate system to external equipment through a webpage protocol.

In one embodiment, the laser ranging method 600 further comprises: and the webpage server receives a selection instruction of the point cloud coordinate system through a webpage protocol and selects to output point cloud image data under a world coordinate system or point cloud image data under a laser ranging device coordinate system to external equipment according to the selection instruction.

In another embodiment, the laser ranging method 600 further comprises: and outputting the point cloud data and the attitude data under the coordinate system of the laser ranging device to the upper computer through the upper computer port, so that the upper computer converts the point cloud data under the coordinate system of the laser ranging device into the world coordinate system according to the attitude data to obtain the point cloud data under the world coordinate system.

In one embodiment, the laser ranging method 600 further comprises: and outputting the point cloud data under the world coordinate system to the upper computer through the upper computer port so that the upper computer can perform visual processing on the point cloud data under the world coordinate system to obtain point cloud image data under the world coordinate system.

In one embodiment, the laser ranging method 600 further comprises: and receiving a selection instruction of the point cloud coordinate system through an upper computer port, and selectively outputting point cloud data under a world coordinate system or point cloud data under a laser ranging device coordinate system to an upper computer according to the selection instruction.

For more details of the laser ranging method 600, reference may be made to the description of the laser ranging apparatus above, and further description is not repeated here. The laser ranging method provided by the embodiment of the invention is used for carrying out visualization processing on the point cloud data based on the webpage server, outputting the point cloud image data to external equipment through a webpage protocol, and browsing the point cloud image through the external equipment.

The embodiment of the invention also provides a movable platform, which comprises any one of the laser ranging devices and a movable platform body, wherein the laser ranging device is carried on the movable platform body. In certain embodiments, the movable platform comprises at least one of an unmanned aerial vehicle, an automobile, a remote control car, a robot, a camera, and a pan-tilt head. When the movable platform is the unmanned aerial vehicle, the movable platform body is the fuselage of the unmanned aerial vehicle. When the movable platform is an automobile, the movable platform body is an automobile body of the automobile. The vehicle may be an autonomous vehicle or a semi-autonomous vehicle, without limitation. When the movable platform is a remote control car, the movable platform body is a car body of the remote control car. When the movable platform is a robot, the movable platform body is the robot. When the movable platform is a camera, the movable platform body is the camera itself. When the movable platform is the cloud platform, the movable platform body is the cloud platform body. The cradle head can be a handheld cradle head, and also can be a cradle head carried on an automobile or an aircraft.

The movable platform of the embodiment of the invention adopts the laser distance measuring device of the embodiment of the invention, so that the movable platform of the embodiment of the invention also has the advantages of the embodiment of the invention.

In the above embodiments, all or part of the implementation may be realized by software, hardware, firmware or any other combination. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the invention to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a Digital Video Disk (DVD)), or a semiconductor medium (e.g., a Solid State Disk (SSD)), among others.

Although the illustrative embodiments have been described herein with reference to the accompanying drawings, it is to be understood that the foregoing illustrative embodiments are merely exemplary and are not intended to limit the scope of the invention thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the scope or spirit of the present invention. All such changes and modifications are intended to be included within the scope of the present invention as set forth in the appended claims.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described device embodiments are merely illustrative, and for example, the division of the units is only one logical functional division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another device, or some features may be omitted, or not executed.

In the description provided herein, numerous specific details are set forth. It is understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Similarly, it should be appreciated that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the invention and aiding in the understanding of one or more of the various inventive aspects. However, the method of the present invention should not be construed to reflect the intent: that the invention as claimed requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

It will be understood by those skilled in the art that all of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or elements of any method or apparatus so disclosed, may be combined in any combination, except combinations where such features are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments may be used in any combination.

The various component embodiments of the invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that a microprocessor or Digital Signal Processor (DSP) may be used in practice to implement some or all of the functionality of some of the modules according to embodiments of the present invention. The present invention may also be embodied as apparatus programs (e.g., computer programs and computer program products) for performing a portion or all of the methods described herein. Such programs implementing the present invention may be stored on computer-readable media or may be in the form of one or more signals. Such a signal may be downloaded from an internet website or provided on a carrier signal or in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The usage of the words first, second and third, etcetera do not indicate any ordering. These words may be interpreted as names.

Claims

1. A laser ranging device, comprising:

a transmitting circuit for transmitting laser pulses;

2. The laser ranging device as claimed in claim 1, wherein the web server is further configured to receive a storage instruction for the point cloud data from the external device through the web protocol, and store the point cloud data in a specified time to a local of the laser ranging device according to the storage instruction.

3. The laser ranging apparatus as claimed in claim 1, wherein the web server is further configured to receive an operation instruction for the point cloud image data from the external device through the web protocol, and process the point cloud image data according to the operation instruction.

4. The laser ranging device as claimed in claim 1, further comprising an inertial measurement unit for measuring the pose of the laser ranging device in real time to obtain pose data time-aligned with the point cloud data.

5. The laser ranging device as claimed in claim 4, wherein the arithmetic circuit is further configured to convert the point cloud data under the coordinate system of the laser ranging device into the world coordinate system according to the pose data to obtain the point cloud data under the world coordinate system.

6. The laser ranging device as claimed in claim 5, wherein the web server is further configured to perform visualization processing on the point cloud data in the world coordinate system to obtain point cloud image data in the world coordinate system.

7. The laser ranging apparatus as claimed in claim 6, wherein the web server is further configured to output the point cloud image data in the world coordinate system to the external device through the web protocol.

8. The laser ranging device as claimed in claim 7, wherein the web server is further configured to receive a selection instruction of a point cloud coordinate system through the web protocol, and to select to output point cloud image data in the world coordinate system or point cloud image data in the laser ranging device coordinate system to the external device according to the selection instruction.

9. The laser ranging device as claimed in claim 4, wherein the laser ranging device is further configured to output the point cloud data and the pose data under the coordinate system of the laser ranging device to an upper computer through an upper computer port, so that the upper computer converts the point cloud data under the coordinate system of the laser ranging device to a world coordinate system according to the pose data to obtain the point cloud data under the world coordinate system.

10. The laser ranging device as claimed in claim 5, wherein the laser ranging device is further configured to output the point cloud data in the world coordinate system to an upper computer through an upper computer port, so that the upper computer can perform visualization processing on the point cloud data in the world coordinate system to obtain point cloud image data in the world coordinate system.

11. The laser ranging device as claimed in claim 10, wherein the laser ranging device is further configured to receive a selection instruction of a point cloud coordinate system through the host computer port, and to selectively output point cloud data in the world coordinate system or point cloud data in the laser ranging device coordinate system to the host computer according to the selection instruction.

12. A laser ranging method is used for a laser ranging device and is characterized in that the laser ranging device comprises a webpage server, and the laser ranging method comprises the following steps:

emitting laser pulses;

receiving at least part of return light pulses of the laser pulses reflected by the measured object, and converting the return light pulses into electric signals;

sampling the electrical signal to obtain a sampling result;

obtaining point cloud data based on the sampling result;

13. The laser ranging method of claim 12, further comprising:

and the webpage server receives a storage instruction of the point cloud data from the external equipment through the webpage protocol, and stores the point cloud data in a specified time to the local laser ranging device according to the storage instruction.

14. The laser ranging method of claim 12, further comprising:

and the webpage server receives an operation instruction for the point cloud image data from the external equipment through the webpage protocol and processes the point cloud image data according to the operation instruction.

15. The laser ranging method of claim 12, wherein the laser ranging device further comprises an inertial measurement unit, the method further comprising:

and measuring the attitude of the laser ranging device in real time through the inertial measurement unit to obtain attitude data aligned with the point cloud data in time.

16. The laser ranging method of claim 15, further comprising:

and converting the point cloud data under the coordinate system of the laser ranging device into a world coordinate system according to the attitude data to obtain the point cloud data under the world coordinate system.

17. The laser ranging method of claim 16, further comprising:

and the web server performs visualization processing on the point cloud data under the world coordinate system to obtain point cloud image data under the world coordinate system.

18. The laser ranging method of claim 17, further comprising:

and the webpage server outputs point cloud image data under the world coordinate system to the external equipment through the webpage protocol.

19. The laser ranging method of claim 18, further comprising:

and the webpage server receives a selection instruction of a point cloud coordinate system through the webpage protocol, and selectively outputs point cloud image data under the world coordinate system or point cloud image data under the laser ranging device coordinate system to the external equipment according to the selection instruction.

20. The laser ranging method of claim 15, further comprising:

outputting the point cloud data and the attitude data under the coordinate system of the laser ranging device to an upper computer through an upper computer port, so that the upper computer converts the point cloud data under the coordinate system of the laser ranging device into a world coordinate system according to the attitude data to obtain the point cloud data under the world coordinate system.

21. The laser ranging method of claim 16, further comprising:

and outputting the point cloud data under the world coordinate system to an upper computer through an upper computer port so that the upper computer can perform visual processing on the point cloud data under the world coordinate system to obtain point cloud image data under the world coordinate system.

22. The laser ranging method of claim 21, further comprising:

and receiving a selection instruction of a point cloud coordinate system through the upper computer port, and selectively outputting point cloud data under the world coordinate system or point cloud data under the coordinate system of the laser ranging device to the upper computer according to the selection instruction.

23. A movable platform, comprising:

the laser ranging device as claimed in any one of claims 1 to 11;

the movable platform body, laser rangefinder set up in on the movable platform body.