Laser radar
The application is a divisional application of a patent application with the application number of 201910295983.9 and the name of 'laser radar', which is filed on 12.04.2019.
Technical Field
The application relates to the field of distance measurement, in particular to a laser radar.
Background
As an important part of the intelligent vehicle environment sensing hardware system, the laser radar (LIDAR) is responsible for important tasks such as road edge detection, obstacle identification, and real-time positioning and mapping (SLAM) in automatic driving. Under the coaxial rotation condition, the communication between the devices on the radar rotor and other fixed devices is mainly realized by the following ways:
1. coaxial data transmission is achieved using slip rings. For example, in a mechanically rotating lidar, the stator of the slip ring is coupled to the lidar stator, and the signal is transmitted at an input to a rotating brush-slip ring connector and then output at an output of the connector. The rotor of the slip ring is connected with the rotor of the laser radar; during rotation, electrical signals are transmitted through signal channels on the slip ring. The main disadvantages of this approach are: when the slip ring is used for realizing coaxial data transmission, the slip ring inevitably has the problem of abrasion, is easy to rub and generate heat, and has short service life.
2. The coaxial data transmission is realized by using an electromagnetic induction coil, and the main defects of the mode are as follows:
when the coaxial data transmission is realized by utilizing the electromagnetic induction coil, the coil generates electromagnetic radiation, and other electromagnetic sensitive devices can be influenced;
moreover, when a plurality of data lines are to be transmitted, the electromagnetic shielding problem among the lines needs to be considered, which leads to more complex signal transmission;
in addition, with the increase of the detection line beam of the laser radar, the requirement on the communication bandwidth is increased immediately, and the communication bandwidth of the electromagnetic induction coil cannot meet the communication requirement of the high-line beam laser radar.
Disclosure of Invention
An object of this application is to provide a laser radar, can shorten the line of walking of each module, the installation is maintained conveniently to laser radar's mechanical reliability is improved.
In order to solve the technical problem, an embodiment of the application discloses a laser radar, which comprises a main shaft, a radar rotor, a base, a first main board, a second main board, an angle measuring component, a power supply component and a communication component, wherein the main shaft is connected with the radar rotor;
the first main plate is fixedly arranged relative to the radar rotor and arranged around the main shaft, and the second main plate is fixedly arranged relative to the base and is closer to the base than the first main plate;
the angle measuring assembly, the power supply assembly and the communication assembly are positioned between the first main board and the second main board, and at least one part of the angle measuring assembly, at least one part of the power supply assembly and at least one part of the communication assembly are arranged around the main shaft;
the angle measuring assembly comprises a first measuring module and a second measuring module, the power supply assembly comprises a first power supply module and a second power supply module, the communication assembly comprises a first communication module and a second communication module, and
the first measuring module, the first power supply module and the first communication module are fixedly arranged relative to the radar rotor, and the second measuring module, the second power supply module and the second communication module are fixedly arranged relative to the radar stator.
Optionally, the communication component, the power supply component and the angle measurement component are arranged in sequence in a radial direction of the main shaft, and the angle measurement component is farther away from the main shaft than the communication component and the power supply component.
Optionally, the first communication module includes at least one light emitting element, the second communication module includes at least one light receiving element corresponding to the light emitting element, and
the light-emitting element and the light-receiving element move relatively, and the light-receiving element is positioned on the optical path of at least one beam of light emitted by the light-emitting element;
the light emitting element is arranged around the main shaft as a center to form an annular light emitting element.
Optionally, the light emitting element comprises at least one light source and an annular optical waveguide;
the light beam emitted by the light source is suitable for being incident to the annular optical waveguide;
the annular optical waveguide can allow at least a part of light axially propagating through the optical waveguide to reach the light receiving element through an outer wall surface of the annular optical waveguide.
Optionally, the light emitting element further comprises a light splitting component and/or a collimating component;
the light splitting component is positioned on a light path of the light guide to which the light beam emitted by the light source is incident and is suitable for equally dividing the light beam received from the light source into light beams transmitted along two directions;
the collimating component is positioned between the light source and the light splitting component.
Optionally, the light emitting element is a ring-shaped light emitting element.
Optionally, the second communication module includes at least one light emitting element, and the first communication module includes at least one light receiving element corresponding to the light emitting element.
Optionally, the second communication module comprises at least one ring-shaped light emitting element; the first communication module includes at least one light receiving element corresponding to the annular light emitting element of the second communication module.
Optionally, the first measuring module includes a code wheel, and the code wheel is arranged around the main shaft;
the second measuring module comprises a light emitting device and a light receiving device;
the light receiving element is located on the optical path of a reflected light beam after the code wheel reflects the light beam emitted by the light emitting device.
Optionally, the power supply module further comprises a magnetic shield box;
the first power supply module comprises a wireless receiving coil, the second power supply module comprises a wireless transmitting coil, and the wireless receiving coil and the wireless transmitting coil are positioned in the magnetic shielding box; and the number of the first and second electrodes,
the wireless receiving coil, the wireless transmitting coil and the magnetic shielding box are arranged around the main shaft.
Optionally, the magnetic shield case includes an L-shaped magnetic permeable member.
The embodiments of the present application include, but are not limited to, the following effects:
1) the components for power supply, communication and angle measurement are arranged between the two mainboards in a centralized manner, and connectors and the like between the mainboards can be used for connecting modules of the components, so that the wiring is short, and the installation and maintenance are convenient.
2) The spindle is not required to be grooved and wired, the integrity of a shaft system can be kept, and the mechanical reliability of the laser radar is improved.
3) Can go out the heat of mainboard through the base, be favorable to the heat dissipation.
4) And all devices are arranged in the metal base, so that the electromagnetic compatibility is facilitated.
5) The annular light-emitting element can ensure the stable receiving of the light signal by the light-receiving element in the rotation process of the rotor and improve the transmission quantity of the downlink light signal transmission.
6) The annular light emitting element requires only one light source, such as a laser, and the remaining optical components are inexpensive and low cost.
7) The annular optical waveguide and the light receiving element can be very close to each other, so that the whole structure is like a thin annular body and occupies small volume.
8) The light splitting component is used for splitting light of the light source, so that the light is transmitted in the annular optical waveguide in a two-way mode, and the very uniform annular luminous band can be synthesized by using the two-way symmetrical attenuation of the optical waveguide.
9) The signal light is concentrated near the optical waveguide, and the optical signal is more concentrated after the reflecting plate is adopted, so that the requirement on the emission power of a light source such as a laser is reduced.
Drawings
FIG. 1 illustrates a schematic diagram of a lidar, according to some embodiments of the present application;
FIG. 2 illustrates a schematic diagram of a ring-shaped light-emitting element, according to some embodiments of the present application;
FIG. 3 illustrates a schematic diagram of light intensity in a ring-shaped light emitting element, according to some embodiments of the present application;
FIG. 4 illustrates a schematic diagram of light transmission in a ring-shaped light emitting element, according to some embodiments of the present application.
Detailed Description
Illustrative embodiments of the present application include, but are not limited to, a lidar.
This application will describe aspects of the illustrative embodiments using terms commonly employed by those skilled in the art to convey the substance of their work to others skilled in the art. It will be apparent, however, to one skilled in the art that some alternative embodiments may be practiced using portions of the described aspects. For purposes of explanation, specific numbers, materials and configurations are set forth in order to provide a thorough understanding of the illustrative embodiments. It will be apparent, however, to one skilled in the art that alternative embodiments may be practiced without the specific details. In other instances, well-known features are omitted or simplified in order not to obscure the illustrative embodiments.
To make the objects, technical solutions and advantages of the present application more clear, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.
According to some embodiments of the present application, a lidar is disclosed. Fig. 1 is a schematic structural diagram of the laser radar. Specifically, as shown in fig. 1, the laser radar includes a main shaft 1, a base 2, a first main board 3, a second main board 4, a radar rotor 5, a communication component, a wireless power supply component, an angle measurement component, a ranging component (not shown), and a control component (not shown). The communication assembly comprises a first communication module and a second communication module, the angle measuring assembly comprises a code disc 10, a light emitting and receiving device 11, and the wireless power supply assembly comprises a wireless transmitting coil 14 and a wireless receiving coil 15. The first communication module includes a ring-shaped light emitting element 6 and a second light receiving element 9, and the second communication module includes a first light emitting element 8 and a first light receiving element 7. The radar rotor 5 rotates around the main shaft 1 under the driving of a motor (not shown), the first main board 3, the distance measuring assembly, the first communication module (including a ring-shaped light-emitting element and a second light-receiving element 9), the code wheel 10 and the wireless receiving coil 15 are fixedly arranged relative to the radar rotor 5, and the ring-shaped light-emitting element, the code wheel 10 and the wireless receiving coil 15 are arranged around the main shaft and centered on the main shaft. The second main board 4, the second communication module (including the first light receiving element 7, the first light emitting element 8), and the wireless transmission coil 14 are fixedly disposed with respect to the main shaft.
It is to be understood that, in the laser radar shown in fig. 1, in order to reduce wiring and facilitate maintenance, the ring-shaped light emitting element 6, the second light receiving element 9, the code wheel 10, the wireless receiving coil 15, the first light receiving element 7, the first light emitting element 8, and the wireless transmitting coil 14 are disposed between the first main board 3 and the second main board 4, and the ring-shaped light emitting element, the second light receiving element 9, the code wheel 10, and the wireless receiving coil 15 are disposed on the first main board 3, and the first light receiving element 7, the first light emitting element 8, and the wireless transmitting coil 14 are disposed on the second main board 4 by using an inter-board connector or the like. Meanwhile, in order to reduce the magnetic leakage of the wireless transmitting coil 14 and the wireless receiving coil 15, an incompletely-closed magnetic shielding box is also arranged outside the wireless transmitting coil 14 and the wireless receiving coil 15, and the magnetic shielding box comprises an L-shaped part 12 which is made of a magnetic conductive material and is fixedly arranged relative to the main shaft, an L-shaped part 13 which is fixedly arranged relative to the radar stator and a magnetic conductive strip 16, wherein the magnetic conductive strip 16 can be fixedly arranged relative to the radar rotor or relative to the base or the main shaft.
The operation of the lidar shown in fig. 1 is as follows:
the first light emitting element 8 of the second communication module sends the ranging instruction information sent by the control component to the second light receiving element 9 of the first communication module, namely, the uplink light signal transmission, the second light receiving element 9 sends the ranging instruction information to the ranging component, and the ranging component starts to perform a ranging task after receiving the ranging instruction information;
the distance measurement result information generated by the distance measurement component executing the distance measurement task is sent to the first light receiving element 7 of the second communication module by the annular light emitting element 6 of the first communication module, that is, downlink light signal transmission is performed, and the control component performs correlation analysis and processing on the distance measurement result information after receiving the distance measurement result information sent by the first light receiving element 7.
In addition, during the operation of the laser radar, the second main board 4 supplies power to the wireless transmitting coil 14, the wireless transmitting coil 14 transmits the power to the wireless receiving coil 15, and the wireless receiving coil 15 supplies power to the ranging component on the radar rotor, so that the ranging component performs a ranging task. Meanwhile, for the code wheel 10 for measuring the angle, in the working process of the laser radar, the light emitting device in the light emitting and receiving device 11 emits a light beam to the code wheel 10, the light beam reflected by the code wheel is received by the light receiving device in the light emitting and receiving device 11, and the receiver obtains the scale value on the code wheel due to the fact that the reflectivity of places with scales and without scales on the code wheel is different, and further obtains the rotating angle or the current direction of the laser radar.
Further, it is understood that, during the operation of the above-described laser radar, the optical signal transmission between the first light-emitting element 8 and the second light-receiving element 9 may be achieved by:
1) the first light emitting element 8 continuously emits light, the second light receiving element 9 always receives light at least once during one rotation of the laser radar, and once light is received, optical signal transmission (i.e. uplink data transmission) between the first light emitting element 8 and the second light receiving element 9 can be realized. These are done in a very short time and are almost negligible with respect to the radar rotation.
2) The code disc 10 can be used for detecting and determining the rotation angle of the laser radar, and after the code disc detects that the laser radar rotates for one circle, the code disc transmits a similar trigger signal to the first light emitting element 8, so that the first light emitting element 8 starts to emit light, and the first light emitting element 8 and the second light receiving element 9 can be aligned after the laser radar rotates for one circle, and at the moment, uplink data transmission is performed. That is, each time the laser radar rotates one circle, the uplink data is transmitted.
3) When uplink data transmission is required, an instruction like a trigger signal is sent through downlink data transmission (i.e. optical signal transmission from the light emitting element 6 to the first light receiving element 7), the first light emitting element 8 starts to emit light continuously after receiving the trigger signal, and then uplink data transmission is performed according to the implementation manner 1).
It is to be understood that other manners may be adopted for uplink data transmission, which is not limited herein. Meanwhile, the uplink data transmission may also be implemented by other devices, for example, in other embodiments, the first light emitting element 8 may be replaced by the annular light emitting element 6.
In addition, it is understood that in some other embodiments of the present application, the relative positions of the communication assembly, the power supply assembly, and the angle measurement assembly may not be sequentially arranged away from the spindle as shown in fig. 1, but may also be arranged in other manners, which are not limited herein. For example, the power supply assembly, the communication assembly and the angle measurement assembly are sequentially arranged away from the main shaft.
It is to be understood that the ring-shaped light emitting element referred to in the embodiments of the present application may be a ring-shaped optical waveguide or a ring-shaped light emitting element. The ring-shaped optical waveguide may be a ring-shaped optical fiber or a similar light emitter such as a ring-shaped light bar, wherein the optical fiber may be a plastic optical fiber, and fig. 2 shows a schematic structural diagram of a ring-shaped light emitting element according to some embodiments of the present application.
As shown in fig. 2, the ring-shaped light emitting element 6 includes a ring-shaped optical fiber 6A, a light source 6B, a collimator 6C, a prism 6D, and a reflection plate 6E. The annular optical fiber 6A obtained by bending the optical fiber and roughening the outer wall of the optical fiber can allow the light transmitted by the annular optical fiber 6A in the axial direction of the optical fiber to partially pass through the outer wall surface of the optical fiber to reach the first light receiving element 7. Further, the optical communication can be achieved only by light leakage caused by bending of the ring-shaped optical fiber without roughening the outer wall of the optical fiber.
The light source 6B may be a laser or any similar light emitting component. The laser may be any type of laser, preferably a laser diode. The light source 6B may also be a light emitting diode.
As shown in fig. 4, the prism 6D can divide the light beam emitted by the light source 6B into light beams transmitted in two directions. For example, a 45 ° prism can equally divide the light into two directions, and other prisms or splitters can be used to divide the light beam from the light source in other ratios, such as 30% for clockwise light and 70% for counterclockwise light. As shown in fig. 3, L1 is an intensity attenuation line of light transmitted clockwise after splitting the light beam of the light source by the splitting component in the ring-shaped optical waveguide, L2 is an intensity attenuation line of light transmitted counterclockwise after splitting the light beam in the ring-shaped optical waveguide, and L3 is a light intensity distribution of light synthesized by light transmitted in two directions in the ring-shaped optical waveguide in each position of the ring-shaped optical waveguide.
Although fig. 2 and 3 illustrate the light emitting element having only one light source, in some embodiments of the present application, two or more light sources may be included, and when the light emitting element includes two light sources, the line connecting the two light sources passes through the axis of the spindle or through the center of the circular optical waveguide.
In addition, in some other embodiments of the present application, the ring-shaped light emitting element may include only any one or two of the light splitting part, the collimating part and the reflecting plate, or none of them. For example, the ring-shaped light emitting element includes only the light source and the ring-shaped light guide, or includes the light source, the ring-shaped light guide, and the light splitting member, or includes the light source, the ring-shaped light guide, the light splitting member, and the reflector.
It is understood that in the present application, a light emitting element may be any device capable of emitting light, including but not limited to laser diodes, light emitting diodes, organic light emitting diodes, laser emitters, and the like. By light receiving element is meant any device capable of detecting a received light signal, including, but not limited to, a photodiode, a photomultiplier tube, a photoresistor, a photodiode, a phototransistor, a photocell, an avalanche diode, and the like.
Further technical solutions of the present application are summarized in the following examples:
example 1: a laser radar comprises a main shaft, a radar rotor, a base, a first main board, a second main board, an angle measuring component, a power supply component and a communication component;
the first main plate is fixedly arranged relative to the radar rotor and arranged around the main shaft, and the second main plate is fixedly arranged relative to the base and closer to the base than the first main plate;
the angle measurement assembly, the power supply assembly and the communication assembly are located between the first main board and the second main board, and at least a part of the angle measurement assembly, at least a part of the power supply assembly and at least a part of the communication assembly are arranged around the main shaft;
the angle measuring assembly includes a first measuring module and a second measuring module, the power supply assembly includes a first power supply module and a second power supply module, the communication assembly includes a first communication module and a second communication module, and
the first measuring module, the first power supply module and the first communication module are fixedly arranged relative to the radar rotor, and the second measuring module, the second power supply module and the second communication module are fixedly arranged relative to the radar stator.
Embodiment 2 the lidar according to embodiment 1, wherein the communication unit, the power supply unit, and the angle measurement unit are arranged in this order in a radial direction of the main shaft, and the angle measurement unit is located at a greater distance from the main shaft than the communication unit and the power supply unit.
Embodiment 3 the lidar according to embodiment 1 or 2, wherein the first communication module includes at least one light emitting element, the second communication module includes at least one light receiving element corresponding to the light emitting element, and
the light-emitting element and the light-receiving element move relatively, and the light-receiving element is positioned on the optical path of at least one light beam emitted by the light-emitting element;
the light emitting element is arranged around the main shaft by taking the main shaft as a center to form an annular light emitting element.
Embodiment 4. the lidar of embodiment 3, wherein the light emitting element comprises at least one light source and an annular optical waveguide;
the light beam emitted by the light source is suitable for being incident to the annular optical waveguide;
the annular optical waveguide can allow at least a part of light propagating axially through the optical waveguide to reach the light receiving element through an outer wall surface of the annular optical waveguide.
Embodiment 5. the lidar of embodiment 3 or 4, wherein the light emitting element further comprises a beam splitting component and/or a collimating component;
the light splitting component is positioned on a light path on which light beams emitted by the light source are incident to the optical waveguide and is suitable for equally dividing the light beams received from the light source into light beams transmitted along two directions;
the collimating component is positioned between the light source and the light splitting component.
Embodiment 6 the lidar of embodiment 3, wherein the light emitting element is a ring-shaped light emitting element.
Embodiment 7 the lidar of any of embodiments 3-6, wherein the second communication module comprises at least one light emitting element and the first communication module comprises at least one light receiving element corresponding to the light emitting element.
Embodiment 8 the lidar of any of embodiments 3-6, wherein the second communication module comprises at least one ring-shaped light-emitting element; the first communication module includes at least one light receiving element corresponding to the annular light emitting element of the second communication module.
Embodiment 9. the lidar of any of embodiments 1-8, wherein the first measurement module comprises a code wheel disposed around the spindle;
the second measuring module comprises a light emitting device and a light receiving device;
the light receiving element is positioned on the light path of a reflected light beam after the coded disc reflects the light beam emitted by the light emitting device.
Embodiment 10 the lidar of any of embodiments 1-9, wherein the power supply module further comprises a magnetic shield box;
the first power supply module comprises a wireless receiving coil, the second power supply module comprises a wireless transmitting coil, and the wireless receiving coil and the wireless transmitting coil are positioned in the magnetic shielding box; and the number of the first and second electrodes,
the wireless receiving coil, the wireless transmitting coil and the magnetic shielding box are arranged around the main shaft.
Embodiment 11 the lidar of embodiment 10, wherein the magnetic shield box comprises an L-shaped magnetically permeable member.
In the drawings, some features of the structures or methods may be shown in a particular arrangement and/or order. However, it is to be understood that such specific arrangement and/or ordering may not be required. Rather, in some embodiments, the features may be arranged in a manner and/or order different from that shown in the illustrative figures. In addition, the inclusion of a structural or methodical feature in a particular figure is not meant to imply that such feature is required in all embodiments, and in some embodiments, may not be included or may be combined with other features.
It is noted that, in the examples and descriptions of this patent, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, the use of the verb "comprise a" to define an element does not exclude the presence of another, same element in a process, method, article, or apparatus that comprises the element.
While the present application has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present application.