Control method of scanner in laser radar, laser radar and control method thereof

Abstract

The invention provides a control method of a scanner in a laser radar, the laser radar and a control method of the laser radar, the scanner comprises a driver and a scanning mirror, the driver comprises a rotor and a stator, and the control method of the scanner comprises the steps that the rotor is driven to reciprocate, so that the scanning mirror forms a scanning view field; wherein the relative rotating speed between the rotor and the stator, along with the change of the mechanical angle of the rotor, meets the following correspondence: the rotating speed of the rotor when moving in a mechanical angle range corresponding to a specific area in the scanning view field is smaller than the rotating speed of the rotor when moving in a mechanical angle range corresponding to a non-specific area; the point cloud density of the specific area in the scanning view field is greater than the point cloud density of the non-specific area. According to the scheme, the point cloud density of the specific area in the scanning view field is larger than the point cloud density of the non-specific area with low laser radar power consumption.

Description

Technical Field

[0001] The present disclosure relates to the field of lidar, and particularly to a method for controlling a scanner in a lidar, a lidar, and a control method thereof. Background Art

[0002] For a lidar, it is generally considered that the middle field of view where an object is located directly in front of the lidar is a specific area of interest, and other fields of view are non - interesting areas, simply referred to as non - specific areas. For the sake of convenience of description, hereinafter, the specific area of interest will be simply referred to as the specific area, and the non - interesting area will be simply referred to as the non - specific area. For example, in order to ensure that there are enough detection points for a distant object in front, it is required that the point cloud density in the specific area of the lidar is relatively large, so as to have a sufficiently small angular resolution, while the perception requirement for an object in the non - specific area is generally relatively weak. Therefore, the point cloud density in the non - specific area can be relatively small, and the angular resolution can also be relatively large. The above - targeted design helps to reduce the data processing volume and power consumption of the lidar.

[0003] However, in existing solutions for achieving a point cloud density in the specific area of the lidar's field of view greater than that in the non - specific area, there is a problem of increasing the power consumption of the lidar.

[0004] The content in the background art section is only the technology known to the applicant, and does not of course represent the prior art in this field. Summary of the Invention

[0005] In view of the above - mentioned technical problems, the present disclosure provides a method for controlling a scanner in a lidar, a lidar, and a control method thereof, which can achieve a point cloud density in the specific area of the scanning field of view greater than that in the non - specific area with a relatively low power consumption of the lidar.

[0006] An embodiment of the present disclosure provides a method for controlling a scanner in a lidar. The scanner includes a driver and a scanning mirror, and the driver includes a rotor and a stator. The control method includes:

[0007] Driving the rotor to reciprocate, so that the scanning mirror forms a scanning field of view; wherein, the relative rotational speed between the rotor and the stator changes with the mechanical angle of the rotor and satisfies the following corresponding relationship: the rotational speed of the rotor when it moves within the mechanical angle range corresponding to the specific area in the scanning field of view is less than the rotational speed when it moves within the mechanical angle range corresponding to the non - specific area, so that the point cloud density in the specific area of the scanning field of view is greater than that in the non - specific area.

[0008] Optionally, the movement process of the rotor includes a uniform - motion stage and a non - uniform - motion stage, wherein the rotor moves at a uniform speed within the mechanical angle range corresponding to the specific area in the scanning field of view.

[0009] Optionally, the rotor moves non-uniformly within a range of mechanical angles corresponding to non-specific regions in the scanning field of view.

[0010] Optionally, the rotor moves non-uniformly within a range of mechanical angles corresponding to the state when the lidar is not scanning.

[0011] Optionally, the rotor reciprocates relative to the equilibrium position, and the relative rotational speed between the rotor and the stator changes with the mechanical angle of the rotor to satisfy the following corresponding relationship:

[0012] On one side of the equilibrium position, the rotor moves in a first direction. When the mechanical angle is within a first range of mechanical angles, the rotational speed remains constant. When the mechanical angle is within a second range of mechanical angles, the rotational speed slowly increases until it reaches the maximum value. When the mechanical angle is within a third range of mechanical angles, the rotational speed rapidly decreases until it becomes zero. And when the rotor moves in a second direction opposite to the first direction, when the mechanical angle is within the third range of mechanical angles, the rotational speed rapidly increases until it reaches the maximum value. When the mechanical angle is within the second range of mechanical angles, the rotational speed slowly decreases. When the mechanical angle is within the first range of mechanical angles, the rotational speed remains constant. Wherein, the first range of mechanical angles, the second range of mechanical angles, and the third range of mechanical angles increase in sequence.

[0013] Optionally, the relative rotational speed between the rotor and the stator changes with the mechanical angle of the rotor to further satisfy the following corresponding relationship:

[0014] On the other side of the equilibrium position, the rotor moves in the second direction. When the mechanical angle is within a fourth range of mechanical angles, the rotational speed remains constant. When the mechanical angle is within a fifth range of mechanical angles, it slowly increases until it reaches the maximum value. When the mechanical angle is within a sixth range of mechanical angles, the rotational speed rapidly decreases until it becomes zero. And when the rotor moves in the first direction, when the mechanical angle is within the sixth range of mechanical angles, the rotational speed rapidly increases until it reaches the maximum value. When the mechanical angle is within the fifth range of mechanical angles, the rotational speed slowly decreases. When the mechanical angle is within the fourth range of mechanical angles, the rotational speed remains constant. Wherein, the fourth range of mechanical angles, the fifth range of mechanical angles, and the sixth range of mechanical angles increase in sequence.

[0015] Optionally, the rotational speed change curve formed by the relative rotational speed between the rotor and the stator changing with the mechanical angle of the rotor is symmetrically distributed.

[0016] Optionally, the relative rotational speed between the rotor and the stator changing with the mechanical angle of the rotor is driven by the resultant torque formed by the first torque and the second torque that match each other between the rotor and the stator, and the resultant torque changes with the mechanical angle of the rotor to satisfy a preset corresponding relationship.

[0017] Optionally, the resultant torque varies with the mechanical angle of the rotor to form a resultant torque curve. In the resultant torque curve, the resultant torque within the mechanical angle range corresponding to a specific area in the scanning field of view of the rotor is less than the resultant torque within the mechanical angle range corresponding to a non-specific area.

[0018] Optionally, the resultant torque curve satisfies the following corresponding relationship:

[0019] On one side of the equilibrium position, the resultant torque does positive work on the rotor within a second mechanical angle range and does negative work on the rotor within a third mechanical angle range, where the third mechanical angle range is greater than the second mechanical angle range, and the negative work done by the resultant torque on the rotor within the third mechanical angle range is greater than the positive work done by the resultant torque on the rotor within the second mechanical angle range.

[0020] Optionally, the resultant torque curve further satisfies the following corresponding relationship:

[0021] On the other side of the equilibrium position, the resultant torque does negative work on the rotor within a fifth mechanical angle range and does positive work on the rotor within a sixth mechanical angle range, where the sixth mechanical angle range is less than the fifth mechanical angle range, and the positive work done by the resultant torque on the rotor within the sixth mechanical angle range is greater than the negative work done by the resultant torque on the rotor within the fifth mechanical angle range.

[0022] Optionally, a first mechanical angle range is included between the equilibrium position and the second mechanical angle range, and a fourth mechanical angle range is included between the equilibrium position and the fifth mechanical angle range. The resultant torque is equal to zero when it is in at least one of the first mechanical angle range and the fourth mechanical angle range.

[0023] Optionally, on one side of the equilibrium position, the first torque does negative work on the rotor as the mechanical angle of the rotor changes; and on the other side of the equilibrium position, the first torque does positive work on the rotor as the mechanical angle of the rotor changes.

[0024] Optionally, on one side of the equilibrium position, the second torque does positive work on the rotor as the mechanical angle of the rotor changes; and on the other side of the equilibrium position, the second torque does negative work on the rotor as the mechanical angle of the rotor changes.

[0025] Optionally, the rotor reciprocates relative to the equilibrium position, and the resultant torque curve is centrosymmetrically distributed with respect to the equilibrium position.

[0026] Optionally, the control method further includes:

[0027] Apply a preset first driving force to the rotor to drive the rotor to start reciprocating motion, and reduce it to a preset second driving force to maintain the natural reciprocating motion of the rotor.

[0028] Optionally, the working frequency of the driver during the reciprocating motion of the rotor is equal to its resonance frequency.

[0029] Optionally, the resonance frequency is determined based on the magnetic stiffness coefficient, geometric parameters of the magnetic spring formed by the rotor and the stator, and the mechanical angle of the rotor.

[0030] Correspondingly, an embodiment of the present disclosure further provides a control method for a lidar, the lidar includes a transmitter and a scanner, the scanner includes a driver and a scanning mirror, and the driver includes a rotor and a stator; the control method includes:

[0031] Control the transmitter to emit detection beams at a certain time interval;

[0032] Control the scanner to scan the detection beams to form a scanning field of view according to the control method for the scanner in any of the above embodiments for the lidar.

[0033] Correspondingly, an embodiment of the present disclosure further provides a lidar, including:

[0034] A transmitter adapted to emit detection beams;

[0035] A controller adapted to control the transmitter to emit detection beams at a certain time interval;

[0036] A scanner, including a driver and a scanning mirror, wherein: the driver includes a rotor and a stator, and drives the rotor to reciprocate; the scanning mirror receives the detection beams and emits the detection beams to form a scanning field of view; wherein, the relative rotational speed between the rotor and the stator changes with the mechanical angle of the rotor to satisfy the following corresponding relationship: the rotational speed of the rotor when moving within the mechanical angle range corresponding to a specific area in the scanning field of view is less than its rotational speed when moving within the mechanical angle range corresponding to a non-specific area, so that the point cloud density in the specific area of the scanning field of view is greater than that in the non-specific area.

[0037] Optionally, the controller is adapted to apply a preset first driving force to the rotor to drive the rotor to start reciprocating motion, and reduce it to a preset second driving force to maintain the natural reciprocating motion of the rotor.

[0038] Optionally, the driver includes:

[0039] A first magnetic group, including a first magnetic component disposed on the rotor and a second magnetic component disposed on the stator, and a first torque is formed between the first magnetic component and the second magnetic component;

[0040] The second magnetic group includes a third magnetic component disposed on the rotor and a fourth magnetic component disposed on the stator. A second torque is formed between the third magnetic component and the fourth magnetic component, and the resultant torque formed by the first torque and the second torque satisfies a preset corresponding relationship as the mechanical angle of the rotor changes.

[0041] Optionally, the first magnetic component includes a first magnetic part and a second magnetic part, and the second magnetic component includes a third magnetic part and a fourth magnetic part, wherein the first magnetic part and the third magnetic part are magnetically repulsive, and the second magnetic part and the fourth magnetic part are magnetically repulsive.

[0042] Optionally, the third magnetic part or the fourth magnetic part includes:

[0043] A magnetic component;

[0044] A fixing component adapted to fix and at least partially enclose the magnetic component.

[0045] Optionally, the fixing component is made of a magnetic conductive material.

[0046] Optionally, the first torque is adapted to be determined based on at least one of the following:

[0047] The facing area between the first magnetic part and the third magnetic part;

[0048] The facing area between the second magnetic part and the fourth magnetic part.

[0049] Optionally, the fourth magnetic component includes an electromagnetic component.

[0050] Optionally, the electromagnetic component includes a tooth slot adapted to accommodate a coil and is disposed opposite to the central region of the third magnetic component.

[0051] Optionally, the second torque is adapted to be determined based on at least one of the following:

[0052] The size of the tooth slot;

[0053] The facing area between the fourth magnetic component and the third magnetic component.

[0054] Using the control method for a scanner in a lidar provided by the present disclosure, by driving the rotor to reciprocate, a scanning field of view is formed by the scanning mirror. When the rotor moves within the mechanical angle range corresponding to a specific area in the scanning field of view, its rotational speed is lower than when it moves within the mechanical angle range corresponding to a non-specific area. For example, the rotor performs reciprocating variable-speed motion, and the point cloud density in the specific area in the scanning field of view is greater than that in the non-specific area. In the present disclosure, only by maintaining the reciprocating variable-speed motion of the rotor, it is possible to achieve that the point cloud density in the specific area in the scanning field of view is greater than that in the non-specific area, without the need for complex control of the arrangement of lasers in the emitter or the repetition frequency of the lasers, nor the need to provide a large amount of electrical energy when the scanner changes speed, which can reduce the power consumption of the lidar.

[0055] In some embodiments, the rotor moves at a constant speed within the mechanical angle range corresponding to a specific area in the scanning field of view, and a point cloud with uniform resolution in the specific area of the scanning field of view can be obtained, which is beneficial to reducing the complexity of data processing and improving the recognition accuracy of objects within the specific area.

[0056] In some embodiments, on one side of the equilibrium position, as the rotor gradually deviates from the equilibrium position along the first direction, the rotational speed changes from remaining constant to slowly rising to a maximum value, and then rapidly decreases to zero. As the rotor gradually approaches the equilibrium position along the second direction opposite to the first direction, the rotational speed of the rotor rapidly rises to the maximum value, then slowly decreases, and then the rotational speed remains constant. When the rotor approaches the equilibrium position on one side of the equilibrium position, the rotational speed is relatively small, and the point cloud density when the mechanical angle is within the first mechanical angle range is greater than that in other areas, so that the point cloud density in a specific area in the scanning field of view can be greater than that in a non-specific area.

[0057] In some embodiments, on the other side of the equilibrium position, as the rotor gradually deviates from the equilibrium position along the second direction, the rotational speed changes from remaining constant to slowly rising to a maximum value, and then rapidly decreases to zero. As the rotor gradually deviates from the equilibrium position along the first direction, the rotational speed rapidly rises to the maximum value, then slowly decreases, and then the rotational speed remains constant. When the rotor approaches the equilibrium position on the other side of the equilibrium position, the rotational speed is relatively small, and the point cloud density when the mechanical angle is within the fourth mechanical angle range is greater than that in other areas, so that the point cloud density in a specific area in the scanning field of view can be greater than that in a non-specific area.

[0058] In some embodiments, the relative rotational speed between the rotor and the stator varies with the mechanical angle of the rotor and is driven by the resultant torque formed by the first torque and the second torque between the rotor and the stator. The resultant torque varies with the mechanical angle of the rotor to form a resultant torque curve. In the resultant torque curve, the resultant torque in the mechanical angle range corresponding to a specific region in the scanning field of view is less than the resultant torque in the mechanical angle range corresponding to a non-specific region, so that the rotational speed of the rotor when moving in the mechanical angle range corresponding to the specific region in the scanning field of view is less than the rotational speed when moving in the mechanical angle range corresponding to the non-specific region. This can make the point cloud density in the specific region of the scanning field of view greater than that in the non-specific region. The resultant torque is generated based on the mutual matching between the rotor and the stator, rather than the driving force generated by controlling a greatly varying electrical signal. This can eliminate the need to design a complex driving circuit or a complex control algorithm, and there is no need to perform complex control on the transmitter. The implementation scheme is simple and can reduce the power consumption of the lidar.

[0059] In some embodiments, on one side of the equilibrium position, the resultant torque does positive work on the rotor in the second mechanical angle range and negative work on the rotor in the third mechanical angle range. The third mechanical angle range is greater than the second mechanical angle range, and the negative work done by the resultant torque on the rotor in the third mechanical angle range is greater than the positive work done on the rotor in the second mechanical angle range. This can make the range of rotational speed change of the rotor in the second mechanical angle range less than that in the third mechanical angle range, enabling the lidar to quickly switch the direction of motion when in the non-scanning state (the rotor is in the third mechanical angle range), so that the lidar can quickly enter the scanning state (the rotor is in the first mechanical angle range and the second mechanical angle range), reducing the non-scanning time of the lidar.

[0060] In some embodiments, on the other side of the equilibrium position, the resultant torque does negative work on the rotor in the fifth mechanical angle range and positive work on the rotor in the sixth mechanical angle range. The sixth mechanical angle range is less than the fifth mechanical angle range, and the positive work done by the resultant torque on the rotor in the sixth mechanical angle range is greater than the negative work done on the rotor in the fifth mechanical angle range. This can make the range of rotational speed change of the rotor in the fifth mechanical angle range less than that in the sixth mechanical angle range, enabling the lidar to quickly enter the scanning state (the rotor is in the fourth mechanical angle range and the fifth mechanical angle range) from the non-scanning state (the rotor is in the sixth mechanical angle range), reducing the non-scanning time of the lidar.

[0061] In some embodiments, a first mechanical angle range is included between the equilibrium position and the second mechanical angle range, and a fourth mechanical angle range is included between the equilibrium position and the fifth mechanical angle range. The resultant torque is equal to zero when in at least one of the first mechanical angle range and the fourth mechanical angle range. In the first mechanical angle range and the fourth mechanical angle range, the rotor is basically in a uniform motion state, and a point cloud with uniform resolution in a specific area of the scanning field of view can be obtained, which is beneficial to reducing the data processing complexity and improving the recognition accuracy of the objects existing in the specific area.

[0062] In some embodiments, after a preset first driving force is applied to the rotor to drive the rotor to start reciprocating motion, it is reduced to a preset second driving force, which can maintain the natural reciprocating variable-speed motion of the rotor, and there is no need to provide a driving force generated by a greatly changing electrical signal to drive the rotor to change speed, thereby reducing the power consumption of the lidar.

[0063] In some embodiments, the operating frequency of the driver during the reciprocating motion of the rotor is equal to its resonant frequency, and when the driver is at the resonant frequency, its gain reaches the maximum. Inputting a very small power to the motor can change a very large angle, thereby reducing the power consumption of the lidar.

[0064] In some embodiments, the resonant frequency is determined based on the magnetic stiffness coefficient, geometric parameters of the magnetic spring formed by the rotor and the stator, and the mechanical angle of the rotor. The natural speed change of the rotor is realized through the charging and discharging of the potential energy of the magnetic spring formed by the rotor and the stator, and the natural speed change of the scanner is realized. There is no need to provide a driving force generated by a greatly changing electrical signal to drive the rotor to change speed, which can save the power consumption of the lidar.

[0065] By using the lidar and its control method in the embodiments of the present disclosure, the scanning mirror forms a scanning field of view by driving the rotor to reciprocate. When the rotor moves in the mechanical angle range corresponding to a specific area in the scanning field of view, its rotational speed is less than its rotational speed when moving in the mechanical angle range corresponding to a non-specific area, realizing the reciprocating variable-speed motion of the rotor. In the reciprocating variable-speed motion of the rotor, the transmitter is controlled to emit detection beams at a certain time interval, without changing the emission power of the transmitter, nor providing a driving force generated by a greatly changing electrical signal to drive the scanner to change speed, and it is possible to achieve a point cloud density in a specific area of the scanning field of view greater than that in a non-specific area with low power consumption.

[0066] In some embodiments, the driver includes a first magnetic group and a second magnetic group. Among them, the first magnetic group includes a first magnetic component disposed on the rotor and a second magnetic component disposed on the stator. A first torque is formed between the first magnetic component and the second magnetic component. The second magnetic group includes a third magnetic component disposed on the rotor and a fourth magnetic component disposed on the stator. A second torque is formed between the third magnetic component and the fourth magnetic component. And the resultant torque formed by the first torque and the second torque satisfies a preset corresponding relationship with the mechanical angle change of the rotor. The charging and discharging of the potential energy of the magnetic spring formed by the rotor and the stator are realized through the resultant torque, and then the natural speed change of the rotor is realized, thereby realizing the natural speed change of the scanner. There is no need to provide a driving force generated by a significantly changing electrical signal to drive the scanner to change speed, so the power consumption of the lidar can be saved. Description of the Drawings

[0067] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings.

[0068] Figure 1 Shows a schematic structural diagram of a scanner of a lidar in some embodiments of the present disclosure;

[0069] Figure 2 Shows a schematic diagram of a rotational speed change curve formed by the relative rotational speed between a rotor and a stator changing with the mechanical angle of the rotor and a schematic diagram of the point cloud distribution in the corresponding area in the scanning field of view in some embodiments of the present disclosure;

[0070] Figure 3 Shows a schematic diagram of a resultant torque curve formed by the resultant torque changing with the mechanical angle of the rotor in some embodiments of the present disclosure;

[0071] Figure 4 Shows a schematic diagram of a first torque curve formed by the first torque changing with the mechanical angle of the rotor in some embodiments of the present disclosure;

[0072] Figure 5 Shows a schematic diagram of a second torque curve formed by the second torque changing with the mechanical angle of the rotor in some embodiments of the present disclosure;

[0073] Figure 6 Shows a schematic structural diagram of a scanner in a lidar in some embodiments of the present disclosure;

[0074] Figure 7Shows a three-dimensional structural schematic diagram of a rotor in some embodiments of the present disclosure;

[0075] Figure 8 Shows a cross-sectional structural schematic diagram of a rotor in some embodiments of the present disclosure;

[0076] Figure 9 Shows an exploded view of the structure of an electromagnetic component in some embodiments of the present disclosure;

[0077] Figure 10 Shows a schematic diagram comparing the frequency response curves of two types of drivers in some embodiments of the present disclosure;

[0078] Figure 11 Shows the flow of a control method for a lidar in some embodiments of the present disclosure;

[0079] Figure 12 Shows a schematic diagram of the structure of a lidar in some embodiments of the present disclosure. Detailed implementation manners

[0080] As described in the background art, it is currently difficult to achieve a point cloud density in a specific area of the scanning field of view greater than that in a non-specific area with a low power consumption of the lidar. Therefore, it is difficult to balance reducing the data processing amount and power consumption of the lidar.

[0081] To address the above problems, the present disclosure provides a control method for a scanner in a lidar, a lidar, and its control solution. The scanner includes a driver and a scanning mirror. The driver includes a rotor and a stator. By driving the rotor to reciprocate, the scanning mirror forms a scanning field of view. When the rotor moves within the mechanical angle range corresponding to a specific area in the scanning field of view, its rotational speed is less than its rotational speed when moving within the mechanical angle range corresponding to a non-specific area, realizing the reciprocating variable-speed movement of the rotor. The point cloud density in the specific area of the scanning field of view is greater than that in the non-specific area. In the above control process, since only the reciprocating variable-speed movement of the rotor needs to be maintained, it is possible to achieve a point cloud density in the specific area of the scanning field of view greater than that in the non-specific area, without the need to independently perform complex control on the arrangement of lasers in the emitter or the repetition frequency of the lasers, and without the need to provide a large amount of electric energy when the scanner changes speed, which can reduce the power consumption of the lidar.

[0082] To enable those skilled in the art to better understand and implement the embodiments of the present disclosure, the concepts, solutions, principles, advantages, etc. of the embodiments of the present disclosure are described in detail below in conjunction with the accompanying drawings and through specific application examples.

[0083] To enable those skilled in the art to better understand the control method for a scanner in a lidar in the embodiments of this specification, the present disclosure provides a structural example for a scanner in a lidar. Refer to Figure 1Schematic structural diagram of a scanner used in a lidar. Among them, the scanner A10 includes a driver A11 and a scanning mirror A12, and the driver A11 includes a rotor A111 and a stator A112.

[0084] In some embodiments, the scanning mirror A12 may be a galvanometer mirror. For example, the scanning mirror A12 may be fixed to the driver A11.

[0085] As Figure 1 shown, the scanning mirror A12 may adopt a reflecting mirror, and the reflecting mirror can reflect the light beam. For example, the scanning mirror A12 may be disposed on the rotor A111, and the rotor A111 drives the scanning mirror to reciprocate within a specific angular range to change the scanning angle of the detection light beam emitted by the lidar to cover the scanning field of view of the lidar.

[0086] In some embodiments, the rotor may be arranged to surround the stator and be able to move around the stator, or the rotor may also be arranged inside the stator. For example, one of the rotor or the stator is provided with a current-carrying coil, and the other of the rotor or the stator is provided with a permanent magnet. By controlling the change of the current in the coil to generate a changing magnetic field and interacting with the magnetic field generated by the permanent magnet, the rotor is driven to reciprocate relative to the stator.

[0087] In the embodiments of the present disclosure, the structure or relative position of each module in the scanner is not limited to Figure 1 the structure shown.

[0088] The present disclosure can achieve a point cloud density in a specific area of the scanning field of view greater than that in a non-specific area with a lower lidar power consumption, and the following control method can be adopted:

[0089] Drive the rotor to reciprocate so that the scanning mirror forms a scanning field of view; among them, the relative rotational speed between the rotor and the stator changes with the mechanical angle of the rotor to satisfy the following corresponding relationship: the rotational speed of the rotor when moving within the mechanical angle range corresponding to the specific area in the scanning field of view is less than its rotational speed when moving within the mechanical angle range corresponding to the non-specific area, so that the point cloud density in the specific area of the scanning field of view is greater than that in the non-specific area.

[0090] In some embodiments, the specific area in the scanning field of view may be the middle area of the scanning field of view, and the non-specific area may be the edge area of the scanning field of view, where the coverage ranges of the middle area and the edge area of the scanning field of view can be set according to actual needs. It can be understood that the specific area in the scanning field of view is not limited to the middle area of the scanning field of view, and can also be set to other areas of the scanning field of view according to the actual scanning requirements of the lidar.

[0091] In some embodiments of the present disclosure, the movement process of the rotor may include a uniform motion stage and a non-uniform motion stage. Among them, the rotor may move at a uniform speed within the mechanical angle range corresponding to a specific area in the scanning field of view. For example, referring to Figure 2 the schematic diagram of the rotational speed change curve formed by the relative rotational speed between a rotor and a stator changing with the mechanical angle of the rotor as shown. Among them, curve LA is the rotational speed change curve formed by the relative rotational speed between the rotor and the stator changing with the mechanical angle of the rotor. The abscissa represents the mechanical angle α of the rotor, the ordinate represents the rotational speed v of the rotor, the origin O represents the equilibrium position. The side on the right side of the origin is one side of the equilibrium position, and the side on the left side of the origin is the other side of the equilibrium position. It is also possible to have the side on the left side of the origin as one side of the equilibrium position and the side on the right side of the origin as the other side of the equilibrium position. The specific area in the scanning field of view may be the middle area CC'. Within the mechanical angle range corresponding to the middle area CC', the rotor may move at a constant speed, such as a uniform speed, which is beneficial to obtaining a point cloud with uniform resolution, such as Figure 2 The evenly distributed dotted lines in the CC' section of the middle area represent the detection beams emitted at a certain time interval. After being reflected by the scanning mirror moving at a uniform speed, a point cloud with uniform resolution is formed in the scanning field of view.

[0092] By adopting the above embodiments, it is beneficial to obtain a point cloud with uniform resolution in the specific area of the scanning field of view, which can reduce the complexity of lidar data processing and improve the recognition accuracy of objects existing in the specific area. In some embodiments, the rotor may move non-uniformly within the mechanical angle range corresponding to the non-specific area in the scanning field of view. For example, continue to refer to Figure 2 , the non-specific area in the scanning field of view may be the edge areas BC and C'B' of the scanning field of view. Within the mechanical angle range corresponding to the edge areas BC or C'B', the rotor may move non-uniformly, which is beneficial to obtaining a point cloud with changing resolution, such as Figure 2 The non-uniformly distributed dotted lines in the BC or C'B' section of the edge area represent the detection beams emitted at a certain time interval. After being reflected by the scanning mirror moving non-uniformly, a non-uniformly distributed point cloud is formed in the scanning field of view, such as a point cloud with changing resolution, so that the point cloud density in the middle area CC' (specific area) of the scanning field of view is greater than the point cloud density in the edge areas BC or C'B' (non-specific area).

[0093] In some embodiments, the rotor may continuously accelerate within the non-specific area of the scanning field of view.

[0094] In some embodiments, the rotor may accelerate in the first sub-area within the non-specific area of the scanning field of view and decelerate in the second sub-area within the non-specific area of the scanning field of view.

[0095] The above is only an example. The movement process of the rotor in the non-specific area of the scanning field of view can be set according to actual needs, as long as the rotational speed is greater than that when the rotor moves within the mechanical angle range corresponding to the specific area in the scanning field of view.

[0096] In some embodiments, the rotor can move non-uniformly within the mechanical angle range corresponding to the state where the lidar is not scanning, for example, it can decelerate. Among them, when the lidar is in the non-scanning state, the transmitter is controlled not to emit light, and only the rotor is in the moving state, and no scanning field of view will be formed. For example, continue to refer to Figure 2 , when the rotor is in area AB or B’A’, the lidar is in the non-scanning state, no scanning field of view is formed in area AB or B’A’, and no point cloud is formed by the lidar either.

[0097] In some embodiments, the rotor can reciprocate relative to the equilibrium position. For example, the rotor can perform reciprocating variable-speed motion relative to the equilibrium position.

[0098] In some embodiments, the relative rotational speed between the rotor and the stator can satisfy the following corresponding relationship as the mechanical angle of the rotor changes:

[0099] On one side of the equilibrium position, when the rotor moves in the first direction and the mechanical angle is within the first mechanical angle range, the rotational speed can remain unchanged; when the mechanical angle is within the second mechanical angle range, the rotational speed slowly rises until it reaches the maximum value; when the mechanical angle is within the third mechanical angle range, the rotational speed rapidly decreases until it becomes zero. And when the rotor moves in the second direction opposite to the first direction and the mechanical angle is within the third mechanical angle range, the rotational speed rapidly rises until it reaches the maximum value; when the mechanical angle is within the second mechanical angle range, the rotational speed slowly decreases; when the mechanical angle is within the first mechanical angle range, the rotational speed remains unchanged. Among them, the first mechanical angle range, the second mechanical angle range, and the third mechanical angle range increase in sequence.

[0100] In some embodiments, continue to refer to Figure 2 , on one side of the equilibrium position O (for example, on the right side of the origin O in curve LA), the rotor moves in the first direction a (for example Figure 1 in the clockwise or counterclockwise direction in Figure 1It moves counterclockwise or clockwise along the [direction], and when the mechanical angle α is within the third mechanical angle range B’A’, the rotational speed α can rapidly increase until it reaches the maximum value. When the mechanical angle α is within the second mechanical angle range C’B’, the rotational speed can slowly decrease. When the mechanical angle is within the first mechanical angle range OC’, the rotational speed v can remain unchanged.

[0101] In some embodiments, the first mechanical angle range can be the mechanical angle range corresponding to a specific area in the scanning field of view, the second mechanical angle range can be the mechanical angle range corresponding to a non-specific area in the scanning field of view, and the third mechanical angle range can be the mechanical angle range when the lidar is in a non-scanning state.

[0102] On one side of the equilibrium position, as the rotor gradually deviates from the equilibrium position along the first direction a, the rotational speed changes from remaining unchanged to slowly increasing to the maximum value, and then rapidly decreases to zero. As the rotor gradually approaches the equilibrium position along the second direction b opposite to the first direction a, the rotational speed rapidly increases to the maximum value, then slowly decreases, and then the rotational speed remains unchanged. When the rotor approaches the equilibrium position on one side of the equilibrium position, the rotational speed is relatively small, and the point cloud density within the first mechanical angle range is greater than the point cloud density in other areas, enabling the point cloud density in a specific area of the scanning field of view to be greater than that in a non-specific area.

[0103] In some embodiments, the relative rotational speed between the rotor and the stator can satisfy the following corresponding relationship as the mechanical angle of the rotor changes:

[0104] On the other side of the equilibrium position, when the rotor moves along the second direction and the mechanical angle is within the fourth mechanical angle range, the rotational speed remains unchanged. When the mechanical angle is within the fifth mechanical angle range, it slowly increases until it reaches the maximum value. When the mechanical angle is within the sixth mechanical angle range, the rotational speed rapidly decreases to zero. And when the rotor moves along the first direction and the mechanical angle is within the sixth mechanical angle range, the rotational speed rapidly increases until it reaches the maximum value. When the mechanical angle is within the fifth mechanical angle range, it slowly decreases. When the mechanical angle is within the fourth mechanical angle range, the rotational speed remains unchanged. Among them, the fourth mechanical angle range, the fifth mechanical angle range, and the sixth mechanical angle range increase in sequence.

[0105] In some embodiments, continue to refer to Figure 2, on the other side of the equilibrium position O (for example, on the left side of the origin O in the curve LA), when the rotor is moving in the second direction b and the mechanical angle α is within the fourth mechanical angle range OC, the rotational speed v can remain constant; when the mechanical angle α is within the fifth mechanical angle range CB, the rotational speed v slowly rises until it reaches the maximum value; when the mechanical angle α is within the sixth mechanical angle range BA, the rotational speed v can rapidly decrease until it becomes zero. When the rotor is moving in the first direction a and the mechanical angle α is within the sixth mechanical angle range BA, the rotational speed v can rapidly rise until it reaches the maximum value; when the mechanical angle α is within the fifth mechanical angle range CB, the rotational speed v can slowly decrease; when the mechanical angle α is within the fourth mechanical angle range OC, the rotational speed v can remain constant.

[0106] In some embodiments, the fourth mechanical angle range can be the mechanical angle range corresponding to a specific area in the scanning field of view, the fifth mechanical angle range can be the mechanical angle range corresponding to a non-specific area in the scanning field of view, and the sixth mechanical angle range can be the mechanical angle range when the lidar is in a non-scanning state.

[0107] On the other side of the equilibrium position, during the process in which the rotor gradually deviates from the equilibrium position along the second direction b, the rotational speed changes from remaining constant to slowly rising to the maximum value, and then rapidly decreases until it becomes zero. During the process in which the rotor gradually deviates from the equilibrium position along the first direction a, the rotational speed rapidly rises to the maximum value, then slowly decreases, and then the rotational speed remains constant. In other words, on the other side of the equilibrium position, the rotational speed when the rotor approaches the equilibrium position is relatively small, and the point cloud density when the mechanical angle is within the fourth mechanical angle range is greater than the point cloud density in other areas, so that the point cloud density in a specific area in the scanning field of view can be greater than the point cloud density in a non-specific area.

[0108] In some embodiments, the present disclosure can reduce the power consumption of the lidar and reduce the amount of data processing when obtaining accurate information about the objects in the scanning field of view. On both sides of the equilibrium position in the present disclosure, each mechanical angle range shrinks as the angle deviating from the equilibrium position increases. As Figure 2 shown, the angular interval covered by the first mechanical angle range OC’ > the angular interval covered by the second mechanical angle range C’B’ > the angular interval covered by the third mechanical angle range B’A’. The angular interval covered by the fourth mechanical angle range OC > the angular interval covered by the fifth mechanical angle range CB > the angular interval covered by the sixth mechanical angle range BA.

[0109] In some embodiments, the rotational speed change curve formed by the relative rotational speed between the rotor and the stator changing with the mechanical angle of the rotor can be symmetrically distributed. For example, the rotational speed change curve can be axially symmetrically distributed with respect to the equilibrium position. As Figure 2As shown, the curve LA is axially symmetrically distributed with respect to the equilibrium position O.

[0110] The rotational speed change curve formed by the relative rotational speed between the rotor and the stator changing with the mechanical angle of the rotor is symmetrically distributed, which can maintain the natural reciprocating variable-speed motion of the rotor and reduce the power consumption of the lidar.

[0111] In some embodiments, the relative rotational speed between the rotor and the stator changing with the mechanical angle of the rotor is driven by the resultant torque formed by multiple torques between the rotor and the stator. The resultant torque changes with the mechanical angle of the rotor and satisfies a preset relationship. The rotational speed of the rotor within the mechanical angle range corresponding to a specific area in the scanning field of view is less than its rotational speed within the mechanical angle range corresponding to a non-specific area. In some embodiments, the resultant torque can be the resultant torque formed by a first torque and a second torque that match each other, and the resultant torque changes with the mechanical angle of the rotor and satisfies a preset relationship.

[0112] In some embodiments, the resultant torque changes with the mechanical angle of the rotor to form a resultant torque curve. In the resultant torque curve, the resultant torque within the mechanical angle range corresponding to a specific area in the scanning field of view of the rotor is less than the resultant torque within the mechanical angle range corresponding to a non-specific area.

[0113] In the resultant torque curve, the resultant torque within the mechanical angle range corresponding to a specific area in the scanning field of view of the rotor is less than the resultant torque within the mechanical angle range corresponding to a non-specific area, which can make the rotational speed of the rotor when moving within the mechanical angle range corresponding to a specific area in the scanning field of view less than its rotational speed when moving within the mechanical angle range corresponding to a non-specific area, and can make the point cloud density in a specific area of the scanning field of view greater than that in a non-specific area. Moreover, the resultant torque is generated based on the mutual matching between the rotor and the stator, rather than the driving force generated by controlling a greatly changing electrical signal. There is no need to design a complex drive circuit or adopt a complex control algorithm, nor is there a need to perform complex control on the transmitter. The implementation scheme is simple and can reduce the power consumption of the lidar.

[0114] In some embodiments, the resultant torque curve can satisfy the following corresponding relationship: on one side of the equilibrium position, the resultant torque does positive work on the rotor within the second mechanical angle range and does negative work on the rotor within the third mechanical angle range, where the third mechanical angle range is greater than the second mechanical angle range, and the negative work done by the resultant torque on the rotor within the third mechanical angle range is greater than the positive work done on the rotor within the second mechanical angle range.

[0115] As Figure 3 The schematic diagram of the resultant torque curve formed by the resultant torque changing with the mechanical angle of the rotor as shown, the resultant torque curve L M0 can satisfy the following corresponding relationship:

[0116] On one side of the equilibrium position (e.g., on the right side of the origin O in curve L M0 ), as the rotor gradually deviates from the equilibrium position along the first direction a, the resultant moment M0 does positive work on the rotor within the second mechanical angle range C'B', and does negative work on the rotor within the third mechanical angle range B'A'. The third mechanical angle range B'A' is greater than the second mechanical angle range C'B', and the negative work done by the resultant moment M0 on the rotor within the third mechanical angle range B'A' is greater than the positive work done on the rotor within the second mechanical angle range C'B'. This can make the speed change range of the rotor within the second mechanical angle range C'B' smaller than that within the third mechanical angle range B'A'. When the lidar is in the non-scanning state (the rotor is within the third mechanical angle range B'A'), it can quickly switch the moving direction so that the lidar can quickly enter the scanning state (the rotor is within the first mechanical angle range OC' and the second mechanical angle range C'B'), reducing the non-scanning time of the lidar.

[0117] In some embodiments, the resultant moment curve may satisfy the following corresponding relationship:

[0118] On the other side of the equilibrium position, the resultant moment does negative work on the rotor within the fifth mechanical angle range, and does positive work on the rotor within the sixth mechanical angle range. The sixth mechanical angle range is smaller than the fifth mechanical angle range, and the positive work done by the resultant moment on the rotor within the sixth mechanical angle range is greater than the negative work done on the rotor within the fifth mechanical angle range.

[0119] Continuing to refer to Figure 3 , on the other side of the equilibrium position (e.g., on the left side of the origin O in curve L M0 ), as the rotor gradually returns to the equilibrium position along the first direction a, the resultant moment M0 does negative work on the rotor within the fifth mechanical angle range CB, and does positive work on the rotor within the sixth mechanical angle range BA. The sixth mechanical angle range BA is smaller than the fifth mechanical angle range CB, and the positive work done by the resultant moment M0 on the rotor within the sixth mechanical angle range BA is greater than the negative work done on the rotor within the fifth mechanical angle range CB. Therefore, the speed change range of the rotor within the fifth mechanical angle range CB can be made smaller than that within the sixth mechanical angle range BA. The lidar can quickly enter the scanning state (the rotor is within the fourth mechanical angle range OC and the fifth mechanical angle range CB) from the non-scanning state (the rotor is within the sixth mechanical angle range BA), reducing the non-scanning time of the lidar.

[0120] In some embodiments, a first mechanical angle range OC' is included between the equilibrium position O and the second mechanical angle range C'B', and a fourth mechanical angle range OC is included between the equilibrium position O and the fifth mechanical angle range CB. The resultant torque M0 is equal to zero when it is in at least one of the first mechanical angle range OC' and the fourth mechanical angle range OC.

[0121] When the resultant torque is equal to zero in the first mechanical angle range OC' and / or the fourth mechanical angle range OC, the rotor has no acceleration, and the corresponding rotational speed v in the first mechanical angle range OC' and / or the fourth mechanical angle range OC is a uniform motion.

[0122] Continuing to refer to Figure 3 the schematic diagram of the resultant torque curve shown, the rotor can reciprocate relative to the equilibrium position O, and the resultant torque curve L M0 can be centrosymmetrically distributed relative to the equilibrium position O.

[0123] By the rotor reciprocating relative to the equilibrium position O, and the resultant torque curve L M0 being centrosymmetrically distributed relative to the equilibrium position, a very small driving force can be applied. For the sake of convenience in description, the force that can maintain the natural reciprocating motion of the rotor is called the "second driving force".

[0124] Adopting the above embodiment, applying a very small second driving force to the rotor can maintain the natural reciprocating variable-speed motion of the rotor, without the need to provide a second driving force generated by a significantly varying electrical signal to drive the rotor's reciprocating variable-speed motion, which can reduce the power consumption of the lidar.

[0125] In some embodiments, as Figure 4 the schematic diagram of the first torque curve formed by the change of the first torque with the mechanical angle of the rotor shown, on one side of the equilibrium position (for example, on the right side of the origin O in the first torque curve L M1 ), during the process of gradually deviating from the equilibrium position along the first direction a, the first torque M1 can do negative work on the rotor as the mechanical angle α of the rotor changes; while on the other side of the equilibrium position (for example, on the left side of the origin O in the first torque curve L M1 ), during the process of gradually returning to the equilibrium position along the first direction a, the first torque M1 can do positive work on the rotor as the mechanical angle α of the rotor changes.

[0126] In some embodiments, as Figure 5 the schematic diagram of the second torque curve formed by the change of the second torque with the mechanical angle of the rotor shown, on one side of the equilibrium position (for example, the second torque curve L M2to the right of the origin O in), during the process of gradually deviating from the equilibrium position along the first direction a, the second moment M2 can do positive work on the rotor as the mechanical angle α of the rotor changes; while on the other side of the equilibrium position (for example, the second moment curve L M2 to the left of the origin O in), during the process of gradually returning to the equilibrium position along the first direction a, the second moment M2 can do negative work on the rotor as the mechanical angle α of the rotor changes.

[0127] In some embodiments, a preset first driving force can be applied to the rotor to drive the rotor to start reciprocating motion, and then, it is reduced to a preset second driving force to maintain the natural reciprocating motion of the rotor. For example, the first driving force can be applied to the rotor to start the reciprocating motion of the rotor, and then, a very small second driving force can be used to maintain the natural reciprocating motion of the rotor.

[0128] The following are some embodiments, combined with Figures 2 to 5 Describe the detailed process of realizing that the point cloud density in a specific area in the scanning field of view is greater than that in a non-specific area by driving the rotor to achieve reciprocating motion.

[0129] Apply the first driving force to the rotor, and the rotor starts to swing reciprocally from the equilibrium position, and the swing amplitude becomes larger and larger until it can reach a preset maximum swing amplitude. Then, apply a second driving force to the rotor to maintain the natural reciprocating motion of the rotor.

[0130] Refer to Figures 3 to 5 , the resultant moment M0 formed by the first moment M1 and the second moment M2 between the rotor and the stator drives the natural reciprocating motion of the rotor to realize the natural charging and discharging of the potential energy of the rotor. There will inevitably be energy losses such as frictional resistance during the movement of the rotor, and the second driving force is only used to overcome the frictional resistance during the movement of the rotor to compensate for the energy loss, so as to maintain the natural reciprocating motion of the rotor.

[0131] For example, refer to Figure 3 , when under the action of the first driving force, the amplitude of the rotor reaches the maximum mechanical angle on one side of the equilibrium position (for example Figure 3 the mechanical angle A in), the rotor starts to move naturally and reciprocally. The rotor moves along the first direction a. When the rotor is in the sixth mechanical angle range BA, continue to refer to Figures 3 to 5 , the resultant moment M0 formed by the first moment M1 and the second moment M2 does positive work on the rotor, and the rotational speed v of the rotor accelerates from 0 until it reaches the maximum value, as Figure 2As shown. When the rotor is in the fifth mechanical angle range CB, the resultant torque M0 formed by the first torque M1 and the second torque M2 does negative work on the rotor, and the mechanical angle B of the rotor starts to decelerate until it moves to the mechanical angle C. Refer to Figure 2 . When the rotor is in the fourth mechanical angle range OC including the equilibrium position O and the first mechanical angle range OC' ( Figure 3 between the mechanical angles C and C' in the middle), the resultant torque M0 formed by the first torque M1 and the second torque M2 is almost 0, and the rotational speed v of the rotor remains almost unchanged. For example, the rotor moves at a constant speed. The resultant torque M0 formed by the first torque M1 and the second torque M2 does positive work on the rotor, and the rotor accelerates in the second mechanical angle range C'B'. When the rotational speed of the rotor slowly rises from the mechanical angle C' until it reaches the mechanical angle B', the rotational speed v of the rotor rises to the maximum value. The resultant torque M0 formed by the first torque M1 and the second torque M2 does negative work on the rotor in the third mechanical angle range B'A', and the rotor quickly decelerates until the rotational speed v is 0 and changes direction. For example, after the rotor decelerates to 0, it gradually returns to the equilibrium position along the second direction b. For example, as Figure 3 shown, starting from the mechanical angle A' and moving towards the mechanical angle A, a frame of point cloud is scanned. When the rotor moves from the mechanical angle A to the mechanical angle A', a frame of point cloud is formed, and when the rotor moves from the mechanical angle A' to the mechanical angle A, a frame of point cloud is also formed.

[0132] In some embodiments, the first mechanical angle range and the fourth mechanical angle range can be the mechanical angle ranges corresponding to specific regions in the scanning field of view, the second mechanical angle range and the fifth mechanical angle range can be the mechanical angle ranges corresponding to non-specific regions in the scanning field of view, and the third mechanical angle range and the sixth mechanical angle range can be the mechanical angle ranges when the lidar is in a non-scanning state. As Figure 2 shown in the point cloud distribution, the detection beam is emitted at a certain time interval. In the specific regions in the scanning field of view corresponding to the first mechanical angle range OC' and the fourth mechanical angle range OC, the rotor is basically in a uniform motion state and the rotational speed is small, and the point cloud is evenly and densely distributed; in the non-specific regions in the scanning field of view corresponding to the second mechanical angle range C'B' and the fifth mechanical angle range CB, the rotor is in a non-uniform motion state, the point cloud is unevenly distributed and sparser than the specific regions. Among them, as the angle deviating from the equilibrium position increases, the point cloud distribution becomes sparser. When the rotor is in the third mechanical angle range B'A' and the sixth mechanical angle range BA, the emitter in the lidar does not emit light, the lidar is in a non-scanning state, there is no point cloud distribution, and the rotor is in a non-uniform motion state and the rotational speed changes violently (the rotational speed changes rapidly between 0 and the maximum value).

[0133] In the above control process of the scanner, there is no need to perform complex control on the repetition frequency of the emitter. Only control the emitter to emit detection beams at certain time intervals in the scanning field of view (for example, trigger the emitter to emit light isochronously). Refer to Figure 3 , the detection beams are emitted isochronously at a certain value within the mechanical angle range B’B, so as to realize the gradual densification of the point cloud from both sides to the middle of the scanning field of view.

[0134] In some embodiments, magnetic components can be arranged on the rotor and the stator. The magnetic potential energy between the magnetic components changes with the air gap (for example, the gap between the rotor and the stator), generating an effect similar to a spring storing or releasing energy. In the embodiments of the present disclosure, the structure that generates the change of magnetic potential energy is called a magnetic spring. The magnetic spring formed by the rotor and the stator and the moment of inertia of the rotor together constitute a second-order resonant system. When the rotor is subjected to an external force and deviates from the equilibrium position, the external force will cause a resultant torque, and this resultant torque will cause the rotor to return to the original equilibrium position, and the reciprocating motion of the rotor can be realized. In some embodiments, the resultant torque can be jointly provided by the first torque and the second torque. After driving the rotor to overcome frictional damping, air damping, etc., the driver formed by the rotor and the stator can operate in a free oscillation state.

[0135] The embodiments of the present disclosure also provide a scanner in a lidar.

[0136] Refer to Figure 6 As shown in the specific structural schematic diagram of a scanner in a lidar, the scanner A20 includes a driver A21 and a scanning mirror A22. Among them, the driver A21 includes a rotor A211 and a stator A212. In some embodiments, the rotor A211 and the stator A212 can be coupled and connected through a shafting AR0 containing bearings; the scanning mirror A22 can be fixed on the rotor A211. In some embodiments, the scanning mirror A22 can be a reflecting mirror, the mirror surface of the reflecting mirror can reflect light beams, and the side of the reflecting mirror opposite to the mirror surface can be fixed on the rotor A211. Based on the above structure, a swinging scanner can be formed. As Figure 6 shown in the relative positions of the rotor A211 and the stator A212, the rotor A211 is in the equilibrium position relative to the stator A212 (for example, the position shown by the dotted line BL), and the rotor A211 can swing reciprocally within a specific angle range on both sides of the equilibrium position BL.

[0137] Taking Figure 6Taking the driver A21 shown as an example, the rotor A211 includes a rotor main body portion A2110, and the rotor main body portion A2110 is arranged to be able to move around the shaft system, for example, reciprocating swing around the shaft system. The stator A212 may include a stator main body portion A2120. Wherein the rotor main body portion A2110 is arranged outside the stator main body portion A2120, and the scanning mirror A22 can be directly connected to the rotor main body portion A2110, which can simplify the structural design. In some embodiments, the rotor main body portion A2110 may also be arranged inside the stator main body portion A2120. For example, the scanning mirror A22 can be fixed to the rotor main body portion A2110 through an extending structure and move with the rotor main body portion A2110. The stator main body portion A2120 and the rotor main body portion A2110 cooperate with each other to enable the rotor to reciprocate from the equilibrium position.

[0138] In some embodiments, the driver may include a first magnetic group and a second magnetic group. The first magnetic group may include one or more sets of magnetic components, and the second magnetic group may also include one or more sets of magnetic components. The embodiments of the present disclosure do not limit the number of magnetic components in each magnetic group.

[0139] In some embodiments, the first magnetic group may include a first magnetic component disposed on the rotor and a second magnetic component disposed on the stator. A first torque may be formed between the first magnetic component and the second magnetic component. The second magnetic group may include a third magnetic component disposed on the rotor and a fourth magnetic component disposed on the stator. A second torque may be formed between the third magnetic component and the fourth magnetic component. The resultant torque formed by the first torque and the second torque satisfies a preset relationship as the mechanical angle of the rotor changes. For example, the first magnetic group and the second magnetic group can be used to form a magnetic spring, and the resultant torque of the magnetic spring changes as the mechanical angle of the rotor changes as Figure 3 shown.

[0140] In some embodiments, continue to refer to Figure 6, the rotor A211 may include a rotor main body portion A2110, a first magnetic component A2111 and a third magnetic component A2112 fixed to the rotor main body portion A2110. The stator A212 may include a stator main body portion A2120, a second magnetic component A2122 and a fourth magnetic component A2121. The first magnetic component A2111 and the second magnetic component A2122 may interact to drive the rotor main body portion A2110 back to the equilibrium position, and the restoring torque generated by the interaction between the first magnetic component A2111 and the second magnetic component A2122 is referred to as the first torque. The third magnetic component A2112 and the fourth magnetic component A2121 may interact to cause the rotor to move away from the equilibrium position, and the torque generated by the interaction between the third magnetic component A2112 and the fourth magnetic component A2121 is referred to as the second torque.

[0141] In some embodiments, the first magnetic component A2111 may be fixed to the rotor main body portion A2110 through a support member. Refer to Figure 6 and Figure 7 , the first magnetic component A2111 may be mounted on the side wall of the rotor main body portion A2110, for example, arranged on the side of the rotor main body portion A2110 through a support member A2113. The third magnetic component A2112 may be arranged to surround the periphery of the fourth magnetic component A2121 in the stator A212. Among them, the structure and quantity of the third magnetic component A2112 may be arranged to cooperate with the fourth magnetic component A2121 (such as the coil A2121b) in the stator A212. For example, the shape of the third magnetic component A2112 may be a tile-shaped magnet or an annular magnet.

[0142] In some embodiments, the first magnetic component includes a first magnetic portion and a second magnetic portion, and the second magnetic component includes a third magnetic portion and a fourth magnetic portion, wherein the first magnetic portion and the third magnetic portion are magnetically repulsive, and the second magnetic portion and the fourth magnetic portion are magnetically repulsive.

[0143] As a specific example, continue to refer to Figure 6 , the first magnetic component A2111 may include a first magnetic portion A2111a and a second magnetic portion A2111b. The first magnetic portion A2111a and the second magnetic portion A2111b may specifically be permanent magnets, or may also be electromagnets or magnetically conductive components; the second magnetic component A2122 includes a third magnetic portion A2122a and a fourth magnetic portion A2122b.

[0144] In some embodiments, the third magnetic part or the fourth magnetic part may include: a magnetic component and a fixing component, wherein the fixing component is adapted to fix and at least partially enclose the magnetic component. In some embodiments, the fixing component may be made of a magnetic conductive material. For example, the magnetic component may be a fixed magnet block, and the fixing component may be a yoke. The yoke at least partially encloses the fixed magnet block, which can concentrate magnetic induction lines and enhance the magnetic induction intensity.

[0145] For example, continuing to refer to Figure 6 , the second magnetic component A2122 may include a third magnetic part A2122a and a fourth magnetic part A2122b. In some embodiments, the second magnetic component A2122 may be separately arranged from the stator main body part A2120, and the third magnetic part A2122a and the fourth magnetic part A2122b are respectively arranged on both sides of the rotor main body part A2110.

[0146] For example, referring to Figure 6 , the third magnetic part A2122a and the fourth magnetic part A2122b include a magnetic component a0 and a fixing component b0. The magnetic component a0 may be a fixed magnet block, and the fixing component b0 may be a yoke. The yoke of the fourth magnetic part A2122b may partially surround the magnetic pole of the fixed magnet block of the fourth magnetic part A2122b that is not opposite to the second magnetic part A2111b. For example, Figure 6 in, the yoke in the fourth magnetic part A2122b surrounds the S pole of the fixed magnet block, and the yoke in the third magnetic part A2122a surrounds the N pole of the fixed magnet block. For example, the yoke can transmit the magnetic field, can be made of a material with a relatively high magnetic permeability, can prevent magnetic leakage, and more magnetic components can be arranged around the rotor to form more restoring components, and the structural design is more flexible.

[0147] In some embodiments, the first torque may be determined based on at least one of the following relationships:

[0148] The facing area between the first magnetic part and the third magnetic part;

[0149] The facing area between the second magnetic part and the fourth magnetic part.

[0150] In some embodiments, by adjusting the facing area between the first magnetic part and the third magnetic part, or the facing area between the second magnetic part and the fourth magnetic part, the magnitude of the repulsive force between two opposite magnetic components can be adjusted. For example, the magnitude of the first torque. The larger the facing area between two opposite magnetic components, the greater the repulsive force.

[0151] For example, continuing to refer to Figure 6, by adjusting the facing area between the first magnetic part A2111a and the third magnetic part A2122a, or the facing area between the second magnetic part A2111b and the fourth magnetic part A2122b, the magnitude of the repulsive force therebetween can be adjusted. For example, the magnitude of the first torque. The larger the facing area between the two opposing magnetic components, the greater the repulsive force.

[0152] In some embodiments, the fourth magnetic assembly may include an electromagnetic assembly. By energizing the electromagnetic assembly, the first driving force or the second driving force can be provided for the driver.

[0153] For example, referring to Figure 6 and Figure 9 , the fourth magnetic assembly A2121 may be an electromagnetic assembly. The fourth magnetic assembly A2121 may include a core A2121a and a coil A2121b. The core A2121a may include a tooth groove A2121a0, and the tooth groove A2121a0 is disposed opposite to the central region of the third magnetic assembly A2112. For example, the core A2121a may be an iron core. For example, referring to Figure 8 , the rotor main body part A2110 may include a rotor support A21101, and the third magnetic assembly A2112 may be fixedly disposed on the rotor support A21101. For example Figure 6 and Figure 8 shown, a groove or a through groove may be provided on the rotor support A21101 so that the third magnetic assembly A2112 can be embedded in the rotor support A21101. As Figure 6 shown, the rotor A211 may be disposed outside the stator A212. For example, the rotor support A21101 covers the outside of the stator main body part A2120 of the stator A212. As Figure 6 shown, the third magnetic assembly A2112 is at least located on the outer periphery of the fourth magnetic assembly A2121 in the stator main body part A2120, and can drive the rotor A211 to move relative to the stator A212 through the fourth magnetic assembly A2121, for example, deviate from the equilibrium position.

[0154] Continuing to refer to Figure 8, the rotor support A21101 may include a rotating shaft A21103. For example, the rotating shaft A21103 may be disposed at the center of the rotor support A21101. The rotating shaft A21103 extends downward from the top of the rotor support A21101 and can cooperate with a bearing (not shown) in the stator main body A2120. In some embodiments, a first magnetic member A21104 may be disposed at the lower part of the rotating shaft A21103, and the first magnetic member A21104 can be magnetically fixed to a second magnetic member (not shown) in the stator main body A2120. For example, the lower part of the rotating shaft A21103 may be provided with a downward-opening groove, and the first magnetic member A21104 is disposed in the downward-opening groove, for example, fixed by pasting or clamping. The first magnetic member A21104 may be a magnet, for example, a cylindrical magnet, to match the shape of the downward-opening groove in the rotating shaft A21103. As Figure 8 shown, an upward-opening cylindrical groove A21102 may also be formed in the upper part of the rotating shaft A21103, which can reduce the mass of the rotor support A21101, reduce the inertia of the rotor support A21101, and can reduce the power consumption of the lidar.

[0155] Referring to Figure 8 , the scanning mirror A22 may be connected to the rotor support A21101. For example, the scanning mirror A22 (such as a reflecting mirror) may be disposed tangentially along the rotation direction of the rotor support A21101, and the scanning mirror A22 is arranged such that its symmetry plane passes through the rotation axis of the rotor support A21101. The third magnetic assembly A2112 may also be fixed to the inner wall of the rotor support A21101. As Figure 8 shown, the third magnetic assembly A2112 may be arranged to cover most of the axial region of the rotor support A21101.

[0156] As Figure 6 shown, the rotor main body A2110 may specifically be a turntable structure, and the third magnetic assembly A2112 may include magnetic tiles distributed on the rotor main body A2110. The shape of the magnetic tile is tile-shaped. For example, a tile-shaped permanent magnet may be used. In some embodiments, there may be one magnetic tile or multiple magnetic tiles. For example, multiple magnetic tiles may be evenly or unevenly distributed on the inner side of the rotor main body A2110. In some embodiments, the third magnetic assembly A2112 includes two magnetic tiles symmetrically distributed on the inner side wall of the rotor main body A2110.

[0157] As Figure 6As shown, after the coil A2121b is energized, it can generate a magnetic field. By changing the magnitude or direction of the current in the coil, etc., a magnetic field change can be generated, and the third magnetic component A2112 in the rotor A211 is driven to move in the changing magnetic field, thereby driving the rotor A211 to move relative to the stator from the equilibrium position.

[0158] When the rotor moves relative to the stator from the equilibrium position, continue to refer to Figure 6 , the position of the second magnetic component A2122 remains fixed, the first magnetic component A2111 moves with the rotor A211, the distance between the first magnetic component A2111 and the second magnetic component A2122 changes, and the kinetic energy of the rotor A211 is converted into the potential energy between the first magnetic component A2111 and the second magnetic component A2122, forming a structure similar to a spring, and its mechanical model can be regarded as a spring element within a certain range (in the embodiments of the present disclosure, simply referred to as a magnetic spring). When the rotor A211 moves to the limit position, the potential energy accumulation of the magnetic spring reaches the maximum, and releasing the potential energy can cause the rotor A211 to change its motion direction and return to the equilibrium position.

[0159] In some embodiments, by parameters such as the magnitude of the magnetic field force between the first magnetic component and the second magnetic component and the distance between them, the stroke of the rotor can be set, that is, the swing angle range of the rotor relative to the stator, and thus the scanning mirror can move within the swing angle range.

[0160] In some embodiments, the second torque is adapted to be determined based on at least one of the following:

[0161] The size of the tooth slot;

[0162] The facing area between the fourth magnetic component and the third magnetic component.

[0163] In some embodiments, the magnitude of the second torque can be adjusted by adjusting the cross-sectional area of the tooth slot. When other parameters remain unchanged, the larger the cross-sectional area of the tooth slot, the relatively larger the second torque.

[0164] In some embodiments, the magnitude of the second torque can be adjusted by adjusting the facing area between the fourth magnetic component A2121 and the third magnetic component A2132. When other parameters remain unchanged, the smaller the facing area, the relatively smaller the second torque.

[0165] In some embodiments, such as Figure 6 and Figure 9As shown, two tooth grooves A2121a0 can be respectively arranged on two opposite sides of the core body and the third magnetic component A2112 (such as a magnetic tile), and the two tooth grooves A2121a0 are respectively adapted to accommodate coils A2121b. In some embodiments, power can be supplied to the coils to provide the required driving force to the driver A21, including a first driving force for driving the rotor A211 to start reciprocating oscillation, and a second driving force for maintaining the natural reciprocating motion of the rotor A211.

[0166] For better understanding and implementation by those skilled in the art, the following combines Figure 6 and Figure 9 , and shows a structure and assembly example of an electromagnetic component. Among them, the fourth magnetic component A2121 can include a core body A2121a, a coil A2121b, and a positioning member A2121c. For example, the core body A2121a is an iron core. As Figure 6 , Figure 8 and Figure 9 shown, the core body A2121a includes an annular part, and a pair of tooth grooves A2121a0 are arranged on the core body A2121a, and the tooth grooves A2121a0 are correspondingly arranged with the coils A2121b. In some embodiments, the core body A2121a can also be set into other shapes or structures. For example, a plurality of tooth grooves A2121a0 can be arranged in the circumferential direction of the core body A2121a. In some embodiments, the notch part in the tooth groove A2121a0 can also cooperate with the third magnetic component A2112 fixed to the rotor main body part A2110 to reduce the movement resistance when the rotor main body part A2110 moves relative to the stator A212. As Figure 6 and Figure 9 shown, a third magnetic component A2112, such as a tile-shaped magnet (abbreviation: magnetic tile), is arranged in the rotor main body part A2110. The position of the tooth groove A2121a0 has a notch, for example, reducing the weight of the core body A2121a. The core body A2121a can be a magnetic conductive material. The magnetic tile has a greater attraction to the part of the core body A2121a without a notch. As Figure 6 and Figure 9 shown, the position of the tooth groove A2121a0 is set to correspond to the central position of the magnetic tile when the rotor is in the balanced position. A pair of third magnetic components A2112 are respectively opposite to a pair of tooth grooves A2121a0 of the core body A2121a in the fourth magnetic component, and a pair of third magnetic components A2112 are symmetrically arranged with respect to the symmetry plane of the scanning mirror A22, which can promote the rotor to move in the direction deviating from the balanced position and further reduce the power consumption requirements.

[0167] In some embodiments, as Figure 9As shown, the positioning member A2121c in the fourth magnetic component A2121 can be used to fix the coil A2121b to cooperate with the tooth groove A2121a0, and can also be used to cooperate with a stator support body (not shown). In some embodiments, the positioning members A2121c are arranged in pairs. As Figure 9 shown, positioning members A2121c are respectively arranged above and below the core body A2121a to be matched with the stator support member.

[0168] Referring to Figure 9 , the positioning member A2121c may include an annular groove A2121c1 and a protruding portion A2121c2. The annular groove A2121c1 can be used to accommodate the coil A2121b. The protruding portion A2121c2 can communicate with the annular groove A2121c1 and extend into the tooth groove A2121a0. The coil A2121b can extend from the communicating position of the annular groove A2121c1 and the protruding portion A2121c2 to the upper and lower sides of the tooth groove A2121a0. The structures of the positioning members A2121c arranged above and below the core body A2121a are basically the same. The coil A2121b can be arranged in a figure-eight structure and be accommodated in the annular grooves A2121c1 in the two positioning members A2121c.

[0169] As Figure 9 shown, the surface of the positioning member A2121c far from the core body A2121a has a pair of first notches A2121c3 corresponding to a pair of tooth grooves A2121a0 and a pair of second notches A2121c4 symmetric with respect to the symmetry plane of the rotor A21 when the scanning mirror A22 is in the balanced position, which is beneficial to accommodating the coil A2121b in the annular groove A2121c1. In some embodiments, the tooth grooves A2121a0 on the core body A2121a are symmetrically arranged with respect to the symmetry plane of the rotor A211 when the scanning mirror A22 is in the balanced position. Correspondingly, the first notches A2121c3 and the second notches A2121c4 in the positioning member A2121c are also symmetrically arranged, which can avoid eccentricity and reduce power consumption.

[0170] In some embodiments, the present disclosure does not limit any physical parameters such as the specific shape, structure, position, or quantity of the third magnetic component A2112 and the fourth magnetic component A2121, as long as the third magnetic component A2112 can match the fourth magnetic component A2121 to generate the required second torque.

[0171] It should be noted that Figure 6The second magnetic group in the shown driver is only an optional example solution, which is essentially a two-pole DC brushless motor structure, very simple and easy to implement. In specific implementation, it can also be achieved by increasing the number of pole pairs, that is, increasing the number of the third magnetic component and the fourth magnetic component.

[0172] In some embodiments, through the mutual cooperation between the first magnetic part and the third magnetic part, and between the second magnetic part and the fourth magnetic part, a first torque between the first magnetic component and the second magnetic component can be obtained, which satisfies Figure 4 The schematic diagram of the first torque curve shown, referring to Figure 6 , starting from the equilibrium position, as the mechanical angle of the rotor increases, the second torque provided by the third magnetic component and the fourth magnetic component is opposite to the rotation direction, that is, the second torque does negative work on the rotor; at the same time, the second torque formed between the third magnetic component and the fourth magnetic component increases with the increase of the mechanical angle. By matching the settings of the third magnetic component and the fourth magnetic component, it satisfies Figure 5 The schematic diagram of the second torque curve shown, that is, the second torque does positive work on the rotation of the rotor until the second torque curve intersects the horizontal axis. The resultant torque formed by the first torque and the second torque satisfies Figure 3 The resultant torque curve graph shown, where when the mechanical angle of the rotor is in the first mechanical angle range (between the mechanical angle ranges OC’), the first torque and the second torque are equal in magnitude and opposite in direction, and the resultant torque is almost 0, and the rotor basically maintains a uniform motion; as the mechanical angle of the rotor increases, when the mechanical angle of the rotor is in the second mechanical angle range (between the mechanical angle ranges C’B’), the positive work done by the second torque gradually becomes greater than the negative work done by the first torque, the resultant torque as a whole does positive work on the rotor, the rotor accelerates, and the speed of the rotor slowly rises to the maximum value; and as the mechanical angle range of the rotor further increases, the mechanical angle of the rotor is in the third mechanical angle range (between the mechanical angle ranges B’A’), the negative work done by the first torque on the rotor continues to increase, and the positive work done by the second torque on the rotor gradually decreases, the rotor starts to decelerate until the speed is 0 and changes the direction of motion, and returns from the maximum value on the right side of the origin to the equilibrium position. As the mechanical angle of the rotor changes, the first torque, the second torque, and the resultant torque generated by their cooperation all conform to Figure 4 、 Figure 5 and Figure 3 The magnitudes at the corresponding mechanical angles on the right side of the origin. Correspondingly, the rotational speed of the rotor conforms to Figure 2The shown rotational speed change curve. After the rotor reaches the equilibrium position, it will continue to deflect towards the other side of the equilibrium position. As the mechanical angle of the rotor deviates from the equilibrium position increases, the first torque, the second torque, and the resultant torque generated by their cooperation all correspondingly conform to Figure 4 , Figure 5 and Figure 3 at the corresponding mechanical angles on the left side of the origin until the rotor starts to decelerate until the speed is 0 and then changes the direction of motion again, and returns from the maximum value of the mechanical angle on the left side of the origin to the equilibrium position. As the mechanical angle of the rotor changes, the first torque, the second torque, and the resultant torque generated by their cooperation all correspondingly conform to Figure 4 , Figure 5 and Figure 3 at the corresponding mechanical angles on the left side of the origin, realizing the natural reciprocating motion of the rotor relative to the equilibrium position.

[0173] For example, the operating frequency of the driver during the reciprocating motion of the rotor is equal to its resonance frequency. Referring to Figure 10 the schematic diagram of the comparison of the frequency response curve of the shown driver, when the operating frequency of the driver is equal to its resonance frequency, its gain reaches the maximum, so a very small driving power can generate a very large angular displacement, reducing power consumption. In some embodiments, the resonance frequency can be determined based on the magnetic stiffness coefficient, geometric parameters of the magnetic spring formed by the rotor and the stator, and the mechanical angle of the rotor. The natural speed change of the rotor is realized through the charging and discharging of the potential energy of the magnetic spring formed by the rotor and the stator, and then the natural speed change of the scanner is realized. There is no need to provide a driving force generated by a large-amplitude changing electrical signal to drive the rotor to change speed, which can save the power consumption of the lidar.

[0174] For example, after the moment of inertia J of the rotor is determined, it can be determined by adjusting the magnetic stiffness coefficient, geometric parameters of the magnetic spring formed by the rotor and the stator, and the mechanical angle of the rotor, as shown in the following formula:

[0175]

[0176] And, K = K1(θ, Y1, K1) + K2(θ, S2); where K represents the total stiffness function of the magnetic spring, K1 represents the magnetic spring stiffness coefficient formed by the fourth magnetic component / the third magnetic component, K2 represents the magnetic spring stiffness coefficient formed by the first magnetic component. θ represents the swing angle, Y1 represents the geometric parameters of the fourth magnetic component, S1 represents the geometric parameters of the third magnetic component; S2 represents the geometric parameters of the second magnetic component.

[0177] For example, the required resonance frequency can be obtained by adjusting parameters such as the facing area between the first magnetic part and the third magnetic part, the facing area between the second magnetic part and the fourth magnetic part, the cross-sectional area of the tooth groove, and the facing area between the fourth magnetic component and the third magnetic component.

[0178] As shown in the previous embodiment, the following takes the driver as a driving motor as an example for illustration. Compared with a conventional motor, the gain of the driver A21 in this embodiment has a peak, as Figure 10 shown, where the dashed line L D1 represents the frequency response curve of a conventional motor, and the solid line L D2 represents the frequency response curve of the motor with the magnetic spring structure in this embodiment. As can be seen from Figure 10 it, in a conventional motor, as the frequency increases, the gain response linearly decreases, while the driver A21 in the present disclosure has a resonance frequency point f0. For example, the frequency point corresponding to the maximum gain is located at the resonance frequency point. At the resonance frequency point, the corresponding gain G has a peak. By setting the operating frequency f of the driver A21 to the resonance frequency f0, a relatively large movement stroke of the rotor can be achieved with a relatively small driving force, and large-angle movement of the scanning mirror A22 can be realized without significantly increasing the power of the driving device. In some embodiments, the resonance frequency f0 can be determined based on parameters such as the magnetic stiffness coefficient, geometric parameters of the magnetic spring formed by the rotor and the stator, and the mechanical angle of the rotor.

[0179] The embodiments of the present disclosure also provide a control method for a lidar. Among them, the lidar may include a transmitter and a scanner, and the scanner may include a driver and a scanning mirror, and the driver includes a rotor and a stator. Referring to Figure 11 the flowchart of the control method for the lidar shown, in a specific implementation, the lidar can be controlled in the following manner:

[0180] S11, controlling the transmitter to emit detection beams at a certain time interval.

[0181] In some embodiments, controlling the transmitter to emit detection beams at a certain time interval within the scanning field of view. For example, referring to Figure 3 , the detection beams are emitted isochronously at a certain value within the mechanical angle range from point B to point B'. The point cloud density obtained by controlling the lidar using the embodiments of the present disclosure is related to the rotation speed of the rotor and the time interval at which the transmitter emits detection beams.

[0182] S12, controlling the scanner to scan the detection beams to form a scanning field of view.

[0183] In some embodiments, the step S12 may control the scanner by using the control method described in any of the foregoing embodiments. For the specific control method, reference may be made to the foregoing embodiments and will not be elaborated herein.

[0184] By using the above control method of the lidar, the rotor is driven to reciprocate, so that the scanning mirror forms a scanning field of view. When the rotor moves within the mechanical angle range corresponding to a specific area in the scanning field of view, its rotational speed is lower than that when it moves within the mechanical angle range corresponding to a non-specific area, thereby realizing the reciprocating variable-speed movement of the rotor. During the reciprocating variable-speed movement of the rotor, the transmitter is controlled to emit detection beams at a certain time interval, without changing the emission power of the transmitter, nor providing a driving force generated by a significantly changing electrical signal to drive the scanner to change speed. In summary, by using the control method of the lidar in the embodiments of the present disclosure, it is possible to achieve a point cloud density in a specific area in the scanning field of view that is greater than that in a non-specific area with lower power consumption.

[0185] Embodiments of the present disclosure also provide a lidar. Refer to Figure 12 the structural schematic diagram of the lidar shown. In some embodiments, the lidar 120 may include a transmitter 121, a controller 122, and a scanner 123, where:

[0186] The transmitter 121 is adapted to emit detection beams;

[0187] The controller 122 is adapted to control the transmitter 121 to emit detection beams at a certain time interval;

[0188] The scanner 123 may include a driver 1231 and a scanning mirror 1232, where: the driver 1231 includes a rotor 12311 and a stator 12312, and drives the rotor 12311 to reciprocate; the scanning mirror 1232 receives the detection beams and emits the detection beams to form a scanning field of view; wherein, the relative rotational speed between the rotor 12311 and the stator 12312 changes with the mechanical angle of the rotor 12311 and satisfies the following corresponding relationship: when the rotor 12311 moves within the mechanical angle range corresponding to a specific area in the scanning field of view, its rotational speed is lower than that when it moves within the mechanical angle range corresponding to a non-specific area, so that the point cloud density in the specific area in the scanning field of view is greater than that in the non-specific area.

[0189] With the above-mentioned lidar 120, the rotor 12311 is driven by the driver 1231 to reciprocate, so that the scanning mirror 1232 forms a scanning field of view. When the rotor 12311 moves within the mechanical angle range corresponding to a specific area in the scanning field of view, its rotational speed is lower than that when it moves within the mechanical angle range corresponding to a non-specific area, realizing the reciprocating variable-speed movement of the rotor 12311. During the reciprocating variable-speed movement of the rotor, the emitter 121 is controlled to emit detection beams at regular time intervals, without changing the emission power of the emitter 121, nor providing a driving force generated by a significantly changing electrical signal to drive the scanner 123 of the scanning device to change speed. Therefore, the point cloud density in a specific area of the scanning field of view can be greater than that in a non-specific area with a relatively low overall system power consumption.

[0190] In some embodiments, the controller 122 is adapted to apply a preset first driving force to the rotor 12311 to drive the rotor 12311 to start reciprocating, and reduce it to a preset second driving force to maintain the natural reciprocating movement of the rotor 12311.

[0191] In some embodiments, the emitter 121, the controller 122, and the scanner 123 can all be implemented in various ways.

[0192] In some embodiments, the emitter 121 may include multiple lasers. In the embodiments of the present disclosure, there are no restrictions on the layout, structure, type, size, etc. between the multiple lasers, and they can emit detection beams in the scanning field of view at regular time intervals under the control of the controller 122. For example, the laser can be a Vertical-Cavity Surface-Emitting Laser (VCSEL) or an Edge Emitting Laser (EEL). Another example is that in the emitter 121, multiple lasers can be arranged in a one-dimensional array or a two-dimensional array.

[0193] In some embodiments, the driver 1231 may include a magnetic component. By utilizing the change in magnetic potential energy between magnetic components with the change of the air gap (such as the gap between the rotor and the stator), a structure similar to a spring storing or releasing energy is generated. In the embodiments of the present disclosure, this structure that generates a change in magnetic potential energy is called a magnetic spring. When the rotor is subjected to an external force and deviates from the equilibrium position, the external force will cause a resultant torque, which will cause the rotor to return to the original equilibrium position, thereby realizing the reciprocating movement of the rotor.

[0194] For the specific implementation manners of the driver 1231, reference can be made to the descriptions of the foregoing embodiments, which will not be elaborated here.

[0195] It should be noted that the specific structures, shapes, sizes, quantities, etc. of the components in the embodiments of the present disclosure are not specifically limited. As long as the components can match each other and meet the actual requirements, it is sufficient. In addition, the terms "first", "second", "third", "fourth", etc. in the embodiments of the present disclosure for limiting different mechanical angle ranges, torques or directions are only used for differential description and do not make any limitations on their specific structures, positions, or functions, etc.

[0196] Although the embodiments of this specification are disclosed as above, the present disclosure is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the scope defined by the claims.

Claims

1. A control method for a scanner in a lidar, characterized in that, The scanner includes a driver and a scanning mirror, and the driver includes a rotor and a stator; The control method includes: Driving the rotor to reciprocate, so that the scanning mirror forms a scanning field of view; wherein, the relative rotational speed between the rotor and the stator changes with the mechanical angle of the rotor and satisfies the following corresponding relationship: the rotational speed of the rotor when moving within the mechanical angle range corresponding to a specific area in the scanning field of view is less than the rotational speed when moving within the mechanical angle range corresponding to a non-specific area, so that the point cloud density in the specific area of the scanning field of view is greater than that in the non-specific area.

2. The control method according to claim 1, characterized in that, The movement process of the rotor includes a uniform motion stage and a non-uniform motion stage, wherein the rotor moves at a uniform speed within the mechanical angle range corresponding to a specific area in the scanning field of view.

3. The control method according to claim 2, characterized in that, The rotor moves non-uniformly within the mechanical angle range corresponding to a non-specific area in the scanning field of view.

4. The control method according to claim 3, characterized in that, The rotor moves non-uniformly within the mechanical angle range corresponding to the state when the lidar is in an unscanned state.

5. The control method according to claim 4, characterized in that, The rotor reciprocates relative to the equilibrium position, and the relative rotational speed between the rotor and the stator changes with the mechanical angle of the rotor and satisfies the following corresponding relationship: On one side of the equilibrium position, the rotor moves in the first direction, and the rotational speed remains unchanged when the mechanical angle is within the first mechanical angle range, the rotational speed slowly rises to the maximum value when the mechanical angle is within the second mechanical angle range, and the rotational speed rapidly decreases to zero when the mechanical angle is within the third mechanical angle range; and the rotor moves in the second direction opposite to the first direction, and the rotational speed rapidly rises to the maximum value when the mechanical angle is within the third mechanical angle range, the rotational speed slowly decreases when the mechanical angle is within the second mechanical angle range, and the rotational speed remains unchanged when the mechanical angle is within the first mechanical angle range; wherein, the first mechanical angle range, the second mechanical angle range and the third mechanical angle range increase in sequence.

6. The control method according to claim 5, characterized in that, The relative rotational speed between the rotor and the stator changes with the mechanical angle of the rotor and also satisfies the following corresponding relationship: On the other side of the equilibrium position, the rotor moves in the second direction, and the rotational speed remains unchanged when the mechanical angle is within the fourth mechanical angle range, the rotational speed slowly rises to the maximum value when the mechanical angle is within the fifth mechanical angle range, and the rotational speed rapidly decreases to zero when the mechanical angle is within the sixth mechanical angle range; and the rotor moves in the first direction, and the rotational speed rapidly rises to the maximum value when the mechanical angle is within the sixth mechanical angle range, the rotational speed slowly decreases when the mechanical angle is within the fifth mechanical angle range, and the rotational speed remains unchanged when the mechanical angle is within the fourth mechanical angle range; wherein, the fourth mechanical angle range, the fifth mechanical angle range and the sixth mechanical angle range increase in sequence.

7. The control method according to claim 6, characterized in that, The rotational speed change curve formed by the relative rotational speed between the rotor and the stator changing with the mechanical angle of the rotor is symmetrically distributed.

8. The control method according to claim 1, characterized in that, The relative rotational speed between the rotor and the stator varies with the mechanical angle of the rotor and is driven by the resultant torque formed by the mutually matching first torque and second torque between the rotor and the stator, and the resultant torque varies with the mechanical angle of the rotor to satisfy a preset corresponding relationship.

9. The control method according to claim 8, characterized in that, The resultant torque varies with the mechanical angle of the rotor to form a resultant torque curve. In the resultant torque curve, the resultant torque of the rotor corresponding to the mechanical angle range of a specific area in the scanning field of view is less than the resultant torque of the rotor corresponding to the mechanical angle range of a non-specific area.

10. The control method according to claim 9, characterized in that, The resultant torque curve satisfies the following corresponding relationship: On one side of the equilibrium position, the resultant torque does positive work on the rotor within a second mechanical angle range and does negative work on the rotor within a third mechanical angle range, where the third mechanical angle range is greater than the second mechanical angle range, and the negative work done by the resultant torque on the rotor within the third mechanical angle range is greater than the positive work done by the resultant torque on the rotor within the second mechanical angle range.

11. The control method according to claim 10, characterized in that, The resultant torque curve also satisfies the following corresponding relationship: On the other side of the equilibrium position, the resultant torque does negative work on the rotor within a fifth mechanical angle range and does positive work on the rotor within a sixth mechanical angle range, where the sixth mechanical angle range is less than the fifth mechanical angle range, and the positive work done by the resultant torque on the rotor within the sixth mechanical angle range is greater than the negative work done by the resultant torque on the rotor within the fifth mechanical angle range.

12. The control method according to claim 11, characterized in that, Between the equilibrium position and the second mechanical angle range, there is a first mechanical angle range, and between the equilibrium position and the fifth mechanical angle range, there is a fourth mechanical angle range. The resultant torque is equal to zero at least in one of the first mechanical angle range and the fourth mechanical angle range.

13. The control method according to claim 12, characterized in that, On one side of the equilibrium position, the first torque does negative work on the rotor as the mechanical angle of the rotor changes; and on the other side of the equilibrium position, the first torque does positive work on the rotor as the mechanical angle of the rotor changes.

14. The control method according to claim 12, characterized in that, On one side of the equilibrium position, the second torque does positive work on the rotor as the mechanical angle of the rotor changes; and on the other side of the equilibrium position, the second torque does negative work on the rotor as the mechanical angle of the rotor changes.

15. The control method according to claim 12, characterized in that, The rotor reciprocates relative to the equilibrium position, and the resultant torque curve is centrosymmetrically distributed with respect to the equilibrium position.

16. The control method according to claim 1, characterized in that, It further includes: Applying a preset first driving force to the rotor to drive the rotor to start reciprocating motion and reducing it to a preset second driving force to maintain the natural reciprocating motion of the rotor.

17. The control method according to claim 1, wherein, The working frequency of the driver during the reciprocating motion of the rotor is equal to its resonant frequency.

18. The control method according to claim 17, wherein, The resonant frequency is determined based on the magnetic stiffness coefficient, geometric parameters of the magnetic spring formed by the rotor and the stator, and the mechanical angle of the rotor.

19. A control method for a lidar, wherein, The lidar includes a transmitter and a scanner, the scanner includes a driver and a scanning mirror, and the driver includes a rotor and a stator; The control method includes: Controlling the transmitter to emit detection beams at a certain time interval; Controlling the scanner to scan the detection beams to form a scanning field of view according to the control method described in any one of claims 1-18.

20. A lidar, wherein, It includes: A transmitter adapted to emit detection beams; A controller, adapted to control the emitter to emit a detection beam at a certain time interval; A scanner, comprising a driver and a scanning mirror, wherein: the driver includes a rotor and a stator, and drives the rotor to reciprocate; the scanning mirror receives the detection beam and emits the detection beam to form a scanning field of view; wherein, the relative rotational speed between the rotor and the stator changes with the mechanical angle of the rotor to satisfy the following corresponding relationship: the rotational speed of the rotor when moving within the mechanical angle range corresponding to a specific area in the scanning field of view is less than its rotational speed when moving within the mechanical angle range corresponding to a non-specific area, so that the point cloud density in the specific area of the scanning field of view is greater than that in the non-specific area.

21. The lidar according to claim 20, wherein, The controller is adapted to apply a preset first driving force to the rotor to drive the rotor to start reciprocating, and reduce it to a preset second driving force to maintain the natural reciprocating motion of the rotor.

22. The lidar according to claim 20, wherein, The driver includes: A first magnetic group, including a first magnetic component disposed on the rotor and a second magnetic component disposed on the stator, and a first torque is formed between the first magnetic component and the second magnetic component; A second magnetic group, including a third magnetic component disposed on the rotor and a fourth magnetic component disposed on the stator, and a second torque is formed between the third magnetic component and the fourth magnetic component, and the resultant torque formed by the first torque and the second torque changes with the mechanical angle of the rotor to satisfy a preset corresponding relationship.

23. The lidar according to claim 22, wherein, The first magnetic component includes a first magnetic part and a second magnetic part, and the second magnetic component includes a third magnetic part and a fourth magnetic part, wherein, the first magnetic part and the third magnetic part are magnetically repulsive, and the second magnetic part and the fourth magnetic part are magnetically repulsive.

24. The lidar according to claim 23, wherein, The third magnetic part or the fourth magnetic part includes: A magnetic component; A fixing component, adapted to fix and at least partially enclose the magnetic component.

25. The lidar according to claim 24, wherein, The fixing component is made of a magnetic conductive material.

26. The lidar according to claim 23, wherein, The first torque is adapted to be determined based on at least one of the following: The facing area between the first magnetic part and the third magnetic part; The facing area between the second magnetic part and the fourth magnetic part.

27. The lidar according to claim 22, wherein, The fourth magnetic component includes an electromagnetic component.

28. The lidar according to claim 27, wherein, The electromagnetic component includes a tooth groove, which is adapted to accommodate a coil and is disposed opposite to the central area of the third magnetic component.

29. The lidar according to claim 28, wherein, The second torque is adapted to be determined based on at least one of the following: The size of the tooth groove; The facing area between the fourth magnetic component and the third magnetic component.

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