Oscillation mirror for rider

Abstract

To provide an oscillation mirror for a rider, which has a mirror connected to a rotor.SOLUTION: A rotor is arranged so as to rotate around a pivot using one or more bearings. A mirror is connected to the rotor, and arranged so as to reflect light emitted from a laser. A first magnet is connected to the rotor. A second magnet is connected to a base. The second magnet is arranged so as to limit angular rotation of the rotor by a pole of the second magnet facing the same pole of the first magnet.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Applications Nos. 63 / 529,278 and 63 / 529,273, both filed on July 27, 2023, the disclosures of which are incorporated by reference in their entireties for all purposes. [Background technology]

[0002]

[0002] Three-dimensional sensors can be applied to autonomous vehicles, drones, robots, security applications, and the like. For example, Lidar projects a light beam and detects the light of the light beam reflected by one or more objects in the environment. Lidar can be used to create a three-dimensional map of an environment or a portion thereof based on detecting the reflected light of the light beam. Scanning Lidar sensors can provide high angular resolution suitable for such applications at a reasonable cost. One example of a scanning Lidar system is U.S. Patent No. 10,690,754, issued June 23, 2020, and incorporated by reference for all purposes. However, improved scanning systems, apparatus, and / or methods are desired. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Pat. No. 10,690,754 Summary of the Invention

[0004]

[0003] The present disclosure relates to, but is not limited to, an oscillating mirror for a lidar. In certain configurations, a system for a lidar includes a rotor arranged to rotate about a pivot using one or more bearings, the rotor including a body surrounding the pivot, a mirror support extending from the body, and / or legs extending from the body, a mirror coupled to the rotor at the mirror support and arranged to reflect light emitted from a laser, a motor arranged to apply a force to the rotor, a first magnet coupled to the legs of the rotor, a base, and / or a second magnet coupled to the base and arranged to limit angular rotation of the rotor with the poles of the second magnet facing the like poles of the first magnet. In some configurations, the legs extend in a direction from the body of the rotor perpendicular to the mirror.

[0005]

[0004] In some configurations, a system for a lidar includes a rotor arranged to rotate about a pivot using one or more bearings, a mirror coupled to the rotor and arranged to reflect light emitted from a laser, a motor arranged to apply a force to the rotor, a first magnet coupled to the rotor, a base, and / or a second magnet coupled to the base and arranged to limit angular rotation of the rotor by the poles of the second magnet facing like poles of the first magnet. In some configurations, a system includes a laser, the laser being a first laser, the system includes a second laser, the mirror being the first mirror, the system includes a second mirror coupled to the rotor, the first laser is positioned to illuminate the first mirror, the second laser is positioned to illuminate the second mirror, the rotor includes a body surrounding a pivot, the rotor further includes a leg extending from the body, a first magnet is coupled to the leg of the rotor, a base includes a first bumper, a second magnet is coupled to the first bumper, the base further includes the second bumper, a third magnet is coupled to the second bumper, the third magnet is positioned to limit angular rotation of the rotor in an opposite direction to which the first bumper limits rotation, and the first magnet includes a first plurality of magnets coupled to the rotor. the first magnet is part of a magnet, the second magnet is part of a second plurality of magnets coupled to the base, the first plurality of magnets are arranged on the rotor with alternating polarity, the second plurality of magnets are arranged on the base with alternating polarity, the first plurality of magnets are arranged to limit angular rotation of the rotor with poles of the second plurality of magnets facing like poles of the first plurality of magnets, the mirror has a width of 1 cm or more, the first magnet and the second magnet are rare earth magnets, the first magnet is mounted parallel to the mirror, and / or the system further comprises an angular encoder arranged to measure an angle of rotation of the rotor, a routing mirror, and / or a memory device containing instructions that, when executed by the one or more processors, adjust the routing mirror to correct for errors in the scan position.

[0006]

[0005] In some configurations, a method of using an oscillating mirror includes rotating a rotor about a pivot using one or more bearings, where the mirror is coupled to the rotor; emitting light from a laser toward the mirror, and using the mirror to reflect light from the laser while the mirror rotates with the rotor; and / or constraining rotation of the rotor using a first magnet and a second magnet, where the first magnet is coupled to the rotor and the second magnet is coupled to a base and the second magnet is positioned to limit angular rotation of the rotor with a pole of the second magnet facing a like pole of the first magnet. In some configurations, the laser is a first laser and the mirror is a first mirror, and the method further includes emitting light from a second laser toward the second mirror simultaneously with emitting light from the first laser toward the first mirror, and reflecting light from the second laser using the second mirror while the second mirror rotates with the rotor, the second mirror is coupled to the rotor, the rotor comprising a body surrounding a pivot, the rotor comprising legs extending from the body, the first magnet is coupled to the legs of the rotor, and the method further includes limiting rotation of the rotor by limiting movement of the legs of the rotor, the base comprises a first bumper, the second magnet is coupled to the first bumper, and the base further comprises a second bumper. the method further includes using a third magnet coupled to the second bumper to limit angular rotation of the rotor in an opposite direction to that in which the first bumper limits rotation, wherein the first magnet is part of a first plurality of magnets coupled to the rotor and the second magnet is part of a second plurality of magnets coupled to the base, the first plurality of magnets are arranged with alternating polarity on the rotor and the second plurality of magnets are arranged with alternating polarity on the base, the first plurality of magnets are arranged to limit angular rotation of the rotor with poles of the second plurality of magnets facing like poles of the first plurality of magnets, the method further includes measuring an angle of rotation of the rotor using an angular encoder, and / or the mirror has a width of 1 cm or more.

[0007]

[0006] Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating various embodiments, are intended for purposes of illustration only and are not intended to necessarily limit the scope of the present disclosure.

[0008]

[0007] The present disclosure is described in conjunction with the accompanying drawings. [Brief description of the drawings]

[0009] [Figure 1A] FIG. 1 illustrates one embodiment of an oscillating LIDAR mirror mounting. [Figure 1B] FIG. 1 illustrates one embodiment of an oscillating LIDAR mirror mounting. [Figure 1C] FIG. 1 illustrates one embodiment of an oscillating LIDAR mirror mounting. [Diagram 2] FIG. 1 illustrates one embodiment of a multi-faceted oscillating mirror for a lidar. [Diagram 3] FIG. 1 illustrates an embodiment of a multi-source lidar system. [Figure 4] FIG. 2 is a perspective view of one embodiment of an oscillating lidar mirror. [Diagram 5] FIG. 5 is a top view of the vibrating lidar mirror of FIG. [Figure 6] FIG. 13 illustrates an embodiment using multiple magnets to restrict rotation of the rotor. [Figure 7] FIG. 13 illustrates an embodiment using a metal shield around the magnet. [Figure 8A] FIG. 1 illustrates one embodiment of a slot arrangement for magnets. [Figure 8B] FIG. 8B illustrates an embodiment of an oscillating mirror using the bumper of FIG. 8A. [Figure 9] 1 is a flow diagram of an embodiment of a process for using an vibrating mirror in a LIDAR system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010]

[0018] In the accompanying drawings, similar components and / or features may have the same reference label. Furthermore, various components of the same type may be distinguished by following the reference label with a dash and a second label that distinguishes between the similar components. When only a first reference label is used herein, the description is applicable to any of the similar components having the same first reference label, regardless of the second reference label.

[0011]

[0019] The following description provides only preferred exemplary embodiment(s) and is not intended to limit the scope, applicability, or configuration of the present disclosure. Rather, the following description of the preferred exemplary embodiment(s) provides those skilled in the art with an enabling description for implementing the preferred exemplary embodiment(s). It will be understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope as set forth in the appended claims.

[0012]

[0020] This disclosure relates generally to laser-based sensors, but not limited to oscillating mirrors for LIDAR. Many laser-based sensors, such as LIDAR, use mechanical scanning in at least one dimension, if not two. Such systems often use a scanning mirror, which may be a rotating polygon or an oscillating mirror. A rotating polygon can have undesirable "dead time" where the mirror facets are not pointing in the desired direction, and the system waits until the polygon has rotated to a preferred angle. When a vertical scanning mirror is combined with a rotating polygon for 2D scanning, it can introduce nonlinearities in the scan line. Using an oscillating mirror (e.g., a galvanometer or galvo mirror) instead of a rotating polygon can overcome some of these issues, but it can be difficult to achieve a large field of view using an oscillating mirror due to mechanical design constraints or excessive power consumption. Many galvo mirrors are limited to a scanning range of 30 degrees to 60 degrees, while some LIDAR applications require a field of view (FOV) of 90 degrees to 120 degrees.

[0013]

[0021] The galvo mirror can operate in a resonant or non-resonant mode. In the resonant mode, the frequency is fixed and determined by the stiffness of the spring and the weight of the mirror. This may be undesirable when the lidar uses a particular frequency (e.g., a frame rate of 30 Hz) or a different frequency (e.g., the ability to operate at a frame rate of 24 Hz or 30 Hz). In some cases, it may be advantageous to change the mirror frequency to allow for higher resolution in certain regions of the lidar's field of view. Furthermore, in the resonant mode, the angular motion of the mirror follows a sine wave, resulting in a faster scanning motion in the center of the field of view and a slower scanning motion at the edges of the field of view. In some configurations, it is preferable to have a nearly constant scanning motion across the FOV.

[0014]

[0022] In non-resonant galvo mirrors, the mirror angular motion can be linear. However, non-resonant galvos are much less efficient and typically use large motors to drive the mirror, whose size can cause packaging issues. Furthermore, large motors consume significant power and can cause thermal issues. Finally, non-resonant galvo mirrors can be limited to scan speeds of tens of Hz at best, which may be insufficient for some imaging applications.

[0015]

[0023] 1A, 1B, and 1C show an embodiment of a system 100 for an oscillating LIDAR mirror. Opposing permanent magnets are used to provide a force for the counter motion of the rotor at the end of each scan. The system 100 comprises a rotor 104 arranged to rotate about a pivot 108 using one or more bearings (e.g., pivot bearing 112). The rotor 104 comprises a rotor body 114 surrounding the pivot 108. A mirror 116 is coupled to the rotor 104 and arranged to reflect light emitted from a laser 120. A motor 124 is arranged to apply a force to the rotor 104. A first magnet 128-1 is coupled to the rotor 104. A second magnet 128-2 is coupled to a base 130. The base 130 is arranged to remain stationary while the rotor 104 rotates about the pivot 108 (e.g., the pivot 108 is fixedly coupled to the base 130). The second magnet 128-2 is positioned to limit angular rotation of the rotor 104 with the poles of the second magnet 128-2 facing the like poles of the first magnet 128-1. When the first magnet 128-1 rotates near the second magnet 128-2, the second magnet 128-2 repels the first magnet 128-1 (e.g., because the north poles of the first magnet 128-1 and the second magnet 128-2 repel each other). The first magnet 128-1 may be referred to as a moving magnet or a rotor magnet. The second magnet 128-2 may be referred to as a bumper magnet or a fixed magnet. A third magnet 128-3 and a fourth magnet 128-4 are also shown in FIG. 1. The third magnet 128-3 is a second moving magnet and the fourth magnet 128-4 is a second bumper magnet. The magnets 128 are permanent magnets.

[0016]

[0024] The rotor 104 rotates the mirror 116 until it is stopped by the bumper magnets (e.g., magnets 128-2 and 128-4). By placing opposing permanent magnets near the end of each direction of travel of the oscillating mirror, the mirror 116 can rapidly reverse its direction of travel by the action of a magnetic field. Energy from the rotor motion is stored in the magnetic field and released back to the rotor when the mirror 116 begins to move in the opposite direction. This results in a very energy efficient operation, reducing the size and power usage of the motor 124. The mirror 116 is fixedly attached to the rotor 104 to prevent relative motion between the mirror 116 and the rotor 104. The magnetic bumper provides a non-contact method for reversing the direction of the mirror pivot. Unlike spring or rubber bumpers, there is little or no wear and tear, vibration is reduced or minimized, and / or energy losses associated with non-contact magnetic bumpers are reduced or minimized.

[0017]

[0025] In some embodiments, the mirror 116 has a width (e.g., measured in a direction perpendicular to the axis of rotation of the rotor 104) of 1, 2, 3, or 4 cm or more, and / or 10, 7, 6, or 5 cm or less. For example, the mirror 116 has a width of 1.5, 2.0, 2.5, or 3.0 inches. In some embodiments, the width of the mirror 116 is 1, 2, 3, or 4 cm or more, as a smaller width may limit the scanning field of view of the lidar system below a desired threshold.

[0018]

[0026] 1A, the first magnet 128-1 and the third magnet 128-3 are attached parallel to the mirror 116 (e.g., the magnetic flux of the first magnet 128-1 and the third magnet 128-3 at the center of each magnet is parallel to the normal of the mirror 116) and at both ends of the mirror 116 (e.g., the first magnet 128-1 is disposed at the left end of the mirror 116 and the third magnet 128-3 is disposed at the right end of the mirror 116). The first magnet 128-1 and the third magnet 128-3 are disposed on the opposite or opposite sides of the mirror 116 (e.g., the first magnet 128-1 and the third magnet 128-3 are on opposite sides of the mirror 116 to the reflective surface of the mirror 116).

[0019]

[0027] 1B shows an embodiment in which the rotor 104 is stopped in a clockwise rotational direction by the second magnet 128-2. The mirror 116 is in an extreme clockwise position where the force between the first magnet 128-1 and the second magnet 128-2 stops and reverses the mirror 116. FIG 1C shows an embodiment in which the rotor 104 is stopped in a counterclockwise rotational direction by the fourth magnet 128-4. The mirror 116 is in an extreme counterclockwise position where the force between the third magnet 128-3 and the fourth magnet 128-4 stops and reverses the mirror 116.

[0020]

[0028] The rotor 104 pivots using mechanical bearings, which can be ball bearings, roller bearings, rod bearings, sleeve bearings, rotary bearings, or other types of bearings. This allows a larger range of scanning motion than typical flexure mechanisms, although flexure bearings can also be used in some embodiments. At the end of each movement, the moving magnet(s) approaches the stationary bumper magnet(s) and the magnetic field is arranged such that the north (or south) pole of the moving magnet pushes against the same pole of the bumper magnet.

[0021]

[0029] The motor 124 uses a magnetic drive with permanent magnets. Unlike torsion springs, which provide a mechanical force when the torsion bar rotates, the magnetic drive is arranged to rotate freely, except for a low amount of friction in the bearing(s), when not acted upon by a magnetic force. Furthermore, the rotor can rotate a full revolution if not restricted by a bumper (e.g., bumper magnets) or other stop. The advantage of using a freely rotating rotor instead of using a torsion spring is that the movement of the mirror 116 has a consistent (or constant) angular velocity within the rider's field of view. The torsion spring provides a non-linear motion. Thus, the system does not use torsion springs (or torsion bars) in some embodiments, but instead uses bearings that allow the rotor 104 to rotate freely about the pivot 108.

[0022]

[0030] In the middle part of the scanning motion, the magnetic field from the permanent magnet is significantly reduced and the mirror 116 is free to pivot at a relatively constant angular velocity. This non-sinusoidal motion is generally preferred over sinusoidal motion with a constantly changing angular velocity. The motor(s) provide a relatively small force to counteract the friction of the air and / or the bearing(s). By varying the power to the motor, the vibration frequency can be varied over a relatively wide range. The more power, the faster the mirror 116 moves, resulting in a higher frequency of vibration. In some embodiments, this is true as long as the bumper magnet has enough force to reverse the direction of movement of the mirror 116 without the moving magnet physically contacting the bumper magnet. In some embodiments, strong magnets (e.g., rare earth magnets) are used. In some embodiments, magnets with a magnetic flux density of 0.75 or more and / or 1.5 or less are used for the bumper magnets.

[0023]

[0031] In some configurations, the system includes a first bumper magnet (e.g., second magnet 128-2) and a second bumper magnet (e.g., fourth magnet 128-4) arranged to limit angular rotation of the rotor in an opposite direction to the first bumper magnet (e.g., the first bumper magnet limits clockwise rotation and the second bumper magnet limits counterclockwise rotation).

[0024]

[0032] FIG 2 illustrates an embodiment of a lidar system 200 that uses a multi-faceted oscillating mirror. The lidar system 200 of FIG 2 includes a rotor 204, a pivot 108, a pivot bearing 112, a first mirror 116-1 and a second mirror 116-2, a first laser 120-1 and a second laser 120-2, a motor 124, a magnet 128, and a base 130. The first mirror 116-1 is coupled to a first mirror support (e.g., a flat or curved surface) of the rotor 204. The second mirror 116-2 is coupled to a second mirror support.

[0025]

[0033] The first laser 120-1 is positioned to illuminate the first mirror 116-1. The second laser 120-2 is positioned to illuminate the second mirror 116-2. The rotor 204 oscillates the mirror 116. The second mirror 116-2 is neither parallel nor perpendicular to the first mirror 116-1. The second mirror 116-2 is set at an arbitrary angle to the first mirror 116-1, which is greater than or equal to 15, 20, 25, 30, or 45 degrees, and / or less than or equal to 120, 90, 60, 45, or 30 degrees.

[0026]

[0034] To increase the field of view of the LIDAR system 200, two lasers 120 and two mirrors 116 can be used.

[0027]

[0035] FIG. 3 illustrates one embodiment of a multi-source lidar system 300. The multi-source lidar system 300 includes the elements shown in FIG. 2, including the rotor 204, the first mirror 116-1, and the second mirror 116-2. The first laser 120-1 of FIG. 2 is part of a first optical module 302-1. The second laser 120-2 of FIG. 2 is part of a second optical module 302-2. The optical module 302 includes a laser and a detector. In some embodiments, the laser is part of a laser array and / or the detector is part of a detector array. The following commonly owned patent applications are incorporated by reference for all purposes: U.S. Patent Application No. 18 / 138,302, filed April 24, 2023, U.S. Patent Application No. 18 / 200,457, filed May 22, 2023, and U.S. Patent Application No. 18 / 531,507, filed December 6, 2023.

[0028]

[0036] Light from a first laser (in a first optical module 302-1) is transmitted to a first field of view (FOV) 304-1 by reflecting off a first mirror 116-1 as the rotor 204 oscillates back and forth. Light from a second laser (in a second optical module 302-2) is transmitted to a second FOV 304-2 by reflecting off a second mirror 116-2 as the rotor 204 oscillates back and forth. The resulting scan range (e.g., FOV 304-1 and FOV 304-2) can be larger than what can be achieved with a single-sided mirror.

[0029]

[0037] The multi-source lidar system 300 includes a first routing mirror 308-1 and a second routing mirror 308-2. Light from the first optical module 302-1 is reflected by the first routing mirror 308-1 toward the first mirror 116-1. Light from the second optical module 302-2 is reflected by the second routing mirror 308-2 toward the second mirror 116-2.

[0030]

[0038] The routing mirror 308 can be used to fold the optical path to make the system compact and / or fit a desired form factor. In some embodiments, the routing mirror 308 is adjusted to correct for errors in the scan position (e.g., as described in the '273 application). Thus, in some configurations, the routing mirror 308 rotates, pivots, tilts, or oscillates a few degrees to correct (e.g., the routing mirror rotates 1, 2, or 3 degrees or more, and / or 5, 8, or 10 degrees or less).

[0031]

[0039] The routing mirror 308 can be used (e.g., rotate, pivot, tilt, or oscillate) to increase the FOV 304. The field of view can be equal to twice the rotation of the mirror. Thus, by rotating the mirror 10 degrees, a 20 degree FOV is created. The routing mirror 308 is configured in some configurations to move (e.g., pivot about an axis parallel to the axis of rotation of the rotor 204) to increase the FOV 304. The routing mirror 308 can rotate, pivot, tilt, or oscillate by 3 degrees, 5 degrees, or 10 degrees or more, and / or 10 degrees, 15 degrees, or 20 degrees or less, in some configurations. For example, the routing mirror 308 rotates + / - 5 degrees (10 degrees total) to provide a 20 degree field of view. The rotor 204 rotates the mirror 116 + / - 10 degrees (20 degrees total) to provide a 40 degree field of view. The combination of the 20 degree field of view of the routing mirror 308 and the 40 degree field of view of the mirror 116 results in an FOV 304 that is 80 degrees wide.

[0032]

[0040] One design constraint of having two movable mirrors in series (e.g., routing mirror 308 and then mirror 116) is that if the first movable mirror moves a lot, the second mirror in series should be designed to be large enough to capture light from the first mirror while the second mirror rotates. Therefore, it may be desirable for the first mirror to move small (e.g., the second mirror is not too large). In some embodiments, mirror 116 is wider than routing mirror 308 and / or mirror 116 moves (e.g., rotated by rotor 204) through a larger angular range than routing mirror 308. In some configurations, the rotation of mirror 116 is 1, 1.25, or 1.5 times or more than the rotation of routing mirror 308 and / or 1.5, 2, 3, 5, 8, 10, 20, or 40 times or less than the rotation of routing mirror 308. For example, the routing mirror 308 rotates 1 or 2 degrees to correct for a particular error, and the mirror 116 rotates 20 degrees, 30 degrees, or 40 degrees. In another example, the routing mirror 308 rotates 10 degrees, and the mirror 116 rotates 20 degrees.

[0033]

[0041] In some configurations, FOV 304-1 and FOV 304-2 are positioned to overlap within intermediate region 312, effectively providing a high resolution region of interest (ROI) in intermediate region 312. For example, first FOV 304-1 is 80 degrees wide and second FOV 304-2 is 80 degrees wide, with second FOV 304-2 overlapping first FOV 304-1 by 40 degrees.

[0034]

[0042] FIG. 4 shows a perspective view of one embodiment of an oscillating LIDAR mirror. A mirror 116 coupled (e.g., fixedly coupled) to a rotor 404 oscillates back and forth to direct light from a laser into the field of view of the LIDAR system. In FIG. 4, a first magnet 128-1, which is a single moving magnet, is positioned on the opposite side of a pivot 408 (e.g., similar to pivot 108 in FIG. 1) from the mirror 116. The rotor 404 comprises a rotor body 410 (e.g., a portion of the rotor 404 surrounding the pivot 408) and legs 412 (e.g., elongated members) extending from the rotor body 410. In the illustrated embodiment, the elongated direction of the legs 412 is perpendicular to the plane of the mirror 116. In FIG. 4, there are two cylindrical bearings 414 between the pivot 408 and the body 410 of the rotor 404.

[0035]

[0043] The first magnet 128-1 is coupled (e.g., fixedly coupled) to the legs 412 of the rotor 404. The second magnet 128-2 is coupled to the first bumper 420-1, and the third magnet 128-3 is coupled to the second bumper 420-2. The bumpers 420 are posts, columns, walls, or other features to which the magnets are attached to stop the rotation of the legs 412 of the rotor 404, thereby stopping the rotation of the rotor 404. The second magnet 128-2 is positioned to limit the angular rotation of the rotor 404 in a counterclockwise direction. The second bumper 420-2 and the third magnet 128-3 are positioned to limit the angular rotation of the rotor 404 in a direction opposite to the first bumper 420-1 and the second magnet 128-2 (e.g., the third magnet 128-3 limits the angular rotation of the rotor 404 in a clockwise direction). The bumper 420 is part of a base 428 .

[0036]

[0044] In some embodiments, rotor 404 is made from aluminum, steel, titanium, or other strong, rigid materials, depending on the particular application and the expected forces acting on rotor 404.

[0037]

[0045] The drive motor may be a rotary motor, typically one in which rotational motion is rapidly alternating by reversing the polarity of the drive voltage. In some embodiments, the drive motor may be a custom designed motor as shown in Figure 4, in which the motor magnets 425 (e.g., motor armature) do not extend completely around the rotor 404 (e.g., to take advantage of the fact that the motor rotates in less than 360, 180, 120, 100, or 90 degrees). The motor stator 430 is also shown.

[0038]

[0046] In some embodiments, a voice coil is embedded in the magnet 128 (eg, on the legs 412 and / or on the bumper 420) to apply an active electromagnetic field on top of the static permanent magnetic field.

[0039]

[0047] FIG. 5 illustrates a top view of the vibrating LIDAR mirror of FIG. 4. FIG. 5 illustrates an embodiment of a system including a rotor 404 arranged to rotate about a pivot (e.g., pivot 408) using one or more bearings (e.g., cylindrical bearing 414). The rotor 404 includes a rotor body 410 that surrounds the pivot. A mirror support 504 extends from the rotor body 410. A leg 412 extends from the rotor body 410. A mirror 116 is coupled to the rotor 404 at the mirror support 504. The mirror 116 is positioned to reflect light emitted from a laser. A motor (e.g., magnet 425 (motor armature) and stator 430) is positioned to apply a force to the rotor 404. A first magnet (e.g., first magnet 128-1 of FIG. 4) is coupled to the leg 412 of the rotor 404. The system includes a first bumper 420-1 and a second bumper 420-2. A second magnet (e.g., second magnet 128-2) is coupled to the first bumper 420-1 and positioned to limit angular rotation of the rotor 404 with the poles of the second magnet facing like poles of the first magnet.

[0040]

[0048] The legs 412 extend from the rotor body 410 in a direction perpendicular to the plane of the mirror 116. The rotor body 410 surrounds a pivot (eg, the rotor body 410 surrounds the pivot 408).

[0041]

[0049] In Figures 4 and 5, there is a single moving magnet (first magnet 128-1) located on the opposite side of the pivot 408 that supports the mirror 116. The single moving magnet is on the legs 412 (as shown in Figure 4). Each side of the moving magnet interacts with a separate bumper magnet (e.g., second magnet 128-2 and third magnet 128-3). In operation, the stator 430 moves the rotor 404 between +25 degrees and -25 degrees. The magnetic bumpers (e.g., magnet 128 on bumper 420 in Figure 5, or second magnet 128-2 and fourth magnet 128-4 in Figure 1) provide an opposing magnetic field to the moving magnet so that rotational momentum is transferred to the magnetic force. This can save energy used by the motor to reverse the rotor 404.

[0042]

[0050] In some configurations, the system further comprises an encoder (eg, an angular encoder) positioned to measure the angle of rotation of the rotor 404 .

[0043]

[0051] In some embodiments, it may be desirable for the mirror to have a constant angular velocity over most of its range of travel, so that the laser also has a constant scanning speed. To this end, the distance over which the moving magnet(s) interact with the bumper magnet(s) can be reduced or minimized by designing the magnetic field to be contained within a limited spatial region. Figures 6-8 show three techniques for achieving this.

[0044]

[0052] Figure 6 shows an embodiment using multiple magnets in the bumper magnet and multiple magnets in the moving magnet. In Figure 6, instead of a single large magnet, several small magnets with alternating poles are used. The moving magnet and bumper magnet use a matched (mirror image) design. Far from the magnet array, the magnetic field is mostly cancelled by the alternating poles.

[0045]

[0053] FIG. 6 illustrates a plurality of magnets 628 (e.g., coupled to leg 412 of FIG. 5). Magnet 628 is placed in place of magnet 128 of FIG. 1 or FIG. 4. In some embodiments, magnet 628 is generally similar to magnet 128, except for being smaller in size. FIG. 6 illustrates a first magnet 628-1, a second magnet 628-2, a third magnet 628-3, and a fourth magnet 628-4. Although four magnets 628 are shown, more or less than four magnets can be used (e.g., 2, 3, 5, 6, 8, etc.). In FIG. 6, first magnet 628-1 and third magnet 628-3 are shown with their south poles facing outward, and second magnet 628-2 and fourth magnet 628-4 are shown with their north poles facing outward. Thus, leg 412 has a plurality of magnets 628 arranged with alternating polarities.

[0046]

[0054] In some embodiments, the first magnet (e.g., first magnet 628-1) is part of a first plurality of magnets coupled to the rotor. The second magnet (e.g., on bumper 420) is part of a second plurality of magnets coupled to the bumper (e.g., a mirror image of magnet 628 in FIG. 6). The first plurality of magnets are arranged with alternating polarity on the rotor (e.g., as shown in FIG. 6). The second plurality of magnets are arranged with alternating polarity on the bumper, with the second plurality of magnets arranged to limit angular rotation of the rotor with poles of the second plurality of magnets facing like poles of the first plurality of magnets.

[0047]

[0055] The alternating poles of magnet 628 suppress the magnetic field, slowing the rotor only when the moving magnet approaches the bumper magnet. By suppressing the magnetic field, the rotor can rotate linearly (e.g., at a constant angular velocity) over a large rotation angle compared to using an unsuppressed magnetic field (e.g., a single magnet without shielding). In some configurations, an unsuppressed magnetic field can cause errors in angle encoders that use magnets to measure angle.

[0048]

[0056] Figure 7 illustrates an embodiment that uses a shield 704 (e.g., metal) around the magnet 628. The magnet is coupled to the bumper 420. Figure 7 illustrates a shield 704 (e.g., made of iron) that is placed around the magnet 628 to help contain or limit the range of the magnetic field of the magnet 628.

[0049]

[0057] FIG. 8A shows one embodiment of a slot arrangement for magnets. FIG. 8 shows a first magnet 128-1, a second magnet 128-2, and a third magnet 128-3. In FIG. 8, two opposing magnets (e.g., second magnet 128-2 and third magnet 128-3, called bumper magnets) are arranged such that there is a slot between the bumper magnets. The bumper magnets are part of one embodiment of a bumper 804. The moving magnet (e.g., first magnet 128-1) is arranged such that it is repelled from the bumper magnet in the bumper 804 when the moving magnet is pushed into the slot. The moving magnet and bumper magnet can also be reversed. By facing each other across a gap where the moving magnet is inserted, the magnetic field outside the bumper 804 can be reduced.

[0050]

[0058] Figure 8B shows an embodiment of an oscillating mirror using bumper 804 from Figure 8A. Mirror 116 is coupled to rotor 104. First magnet 128-1 and second magnet 128-2 are coupled to the rotor (e.g., positioned on opposite sides of mirror 116 as shown in Figure 8B, or perpendicular to leg 412 in Figure 4, creating a "t" with leg 412).

[0051]

[0059] 9 shows a flow diagram of one embodiment of a process 900 for using an oscillating mirror in a lidar system. Process 900 begins in step 904 with rotating a rotor about a pivot using one or more bearings. A mirror is coupled to the rotor. For example, mirror 116 is coupled to rotor 204 of FIG. 2, and mirror 116 is coupled to rotor 404 of FIG. 4.

[0052]

[0060] In step 908, light is emitted from a laser toward a mirror. For example, light from laser 120 is emitted toward mirror 116 in FIG.

[0053]

[0061] In step 912, light from the laser is reflected using a mirror while the mirror rotates with the rotor. For example, light reflected by mirror 116 in FIG. 3 is directed toward field of view 304 as rotor 204 rotates mirror 116.

[0054]

[0062] In step 916, the rotation of the rotor is limited using a first magnet and a second magnet. The first magnet is coupled to the rotor and the second magnet is coupled to the base. The second magnet is positioned to limit the angular rotation of the rotor by the poles of the second magnet facing the like poles of the first magnet. For example, the second magnet 128-2 stops the rotation of the rotor by facing the first magnet 128-1 of FIGS. 1, 2, and 4.

[0055]

[0063] Various features described herein, e.g., methods, apparatus, computer-readable media, etc., can be implemented using a combination of dedicated components, programmable processors, and / or other programmable devices. Some processes described herein can be implemented on the same processor or different processors. Where some components are described as being configured to perform certain operations, such configuration can be achieved, for example, by designing electronic circuitry to perform the operations, by programming a programmable electronic circuit (such as a microprocessor) to perform the operations, or by a combination thereof. Furthermore, while the above-described embodiments may refer to specific hardware and software components, one skilled in the art will appreciate that different combinations of hardware and / or software components may also be used, and that certain operations described as being implemented in hardware may be implemented in software, or vice versa.

[0056]

[0064] In the above description, details are set forth to provide an understanding of the embodiments. However, it will be understood that the embodiments may be practiced without some of the specific details. In some instances, well-known circuits, processes, algorithms, structures, and techniques are not shown in the figures.

[0057]

[0065] While the principles of the present disclosure have been described above with reference to specific apparatus and methods, it is to be understood that this description is made by way of example only and not as a limitation on the scope of the present disclosure. The embodiments were chosen and described in order to explain the principles and practical applications to enable those skilled in the art to utilize the invention in various embodiments with various modifications as appropriate for the particular applications intended. It is to be understood that the description is intended to cover modifications and equivalents.

[0058]

[0066] It is also noted that the embodiments may be described as a process that is depicted as a flowchart, a flow diagram, a data flow diagram, a structure diagram, or a block diagram. Although a flowchart may describe operations as a series of processes, many of the operations may be performed in parallel or simultaneously. In addition, the order of operations may be rearranged. A process is terminated when its operations are completed, but may have additional steps not included in the diagram. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc.

[0059]

[0067] The enumeration of "a," "an," or "the" is intended to mean "one or more," unless specifically indicated to the contrary. All patents, patent applications, publications, and descriptions referred to herein are incorporated by reference in their entirety for all purposes. None are admitted to be prior art.

[0060]

[0068] The specific details of the particular embodiments may be combined in any suitable manner without departing from the spirit and scope of the embodiments of the invention, however, other embodiments of the invention may be directed to the specific embodiments with respect to each individual aspect, or to particular combinations of these individual aspects.

[0061]

[0069] The foregoing description of the embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the above teachings. The embodiments were chosen and described in order to explain the principles of the invention and its practical application, thereby enabling those skilled in the art to utilize the invention in various embodiments, and with various modifications suited to the particular applications intended. [Explanation of symbols]

[0062] 100 Systems 104 Rotor 108 Pivot 112 Pivot bearing 114 Rotor body 116 Mirror 116-1 First Mirror 116-2 Second Mirror 120 Laser 120-1 First Laser 120-2 Second Laser 124 Motor 128 Magnet 128-1 First Magnet 128-2 Second Magnet 128-3 The third magnet 128-4 The Fourth Magnet 130 Base 200 Rider System 204 Rotor 300 Multi-Source Lidar System 302 Optical Module 302-1 First optical module 302-2 Second optical module 304 Field of view (FOV) 304-1 First Field of View (FOV) 304-2 Second Field of View (FOV) 308 Routing Mirror 308-1 First routing mirror 308-2 Second routing mirror 312 Intermediate area 404 Rotor 408 Pivot 410 Rotor body 412 Legs 414 Bearings 420 Bumper 420-1 First Bumper 420-2 Second Bumper 425 Magnet 428 Base 430 Motor Stator 504 Mirror support 628 Magnet 628-1 First Magnet 628-2 Second Magnet 628-3 Third Magnet 628-4 The Fourth Magnet 704 Shield 804 Bumper

Claims

1. A rotor arranged to rotate about a pivot using one or more bearings, said rotor comprising: a body surrounding the pivot; a mirror support extending from the body; A leg extending from the body; A rotor comprising: a mirror coupled to the rotor at the mirror support and positioned to reflect light emitted from a laser; a motor arranged to apply a force to the rotor; a first magnet coupled to the leg of the rotor; With the base, a second magnet coupled to the base and positioned to limit angular rotation of the rotor with poles of the second magnet facing like poles of the first magnet; A system for riders that includes:

2. The system of claim 1 , wherein the legs extend in a direction from the body of the rotor perpendicular to the mirror.

3. a rotor arranged to rotate about a pivot using one or more bearings; a mirror coupled to the rotor and positioned to reflect light emitted from a laser; a motor arranged to apply a force to the rotor; a first magnet coupled to the rotor; With the base, a second magnet coupled to the base and positioned to limit angular rotation of the rotor with poles of the second magnet facing like poles of the first magnet; A system for riders that includes:

4. the system comprises the laser; the laser is a first laser, the system comprising a second laser; the mirror is a first mirror, the system comprising a second mirror coupled to the rotor; the first laser is positioned to illuminate the first mirror; the second laser is positioned to illuminate the second mirror; The system of claim 3.

5. The system of claim 3 , wherein the rotor comprises a body surrounding the pivot.

6. the rotor further comprising legs extending from the body; the first magnet is coupled to the leg of the rotor; The system of claim 5.

7. the base includes a first bumper; the second magnet is coupled to the first bumper; the base further comprises a second bumper; a third magnet is coupled to the second bumper, the third magnet being positioned to limit angular rotation of the rotor in an opposite direction to that in which the first bumper limits rotation; The system of claim 3.

8. the first magnet is part of a first plurality of magnets coupled to the rotor; the second magnet is part of a second plurality of magnets coupled to the base; the first plurality of magnets are arranged on the rotor with alternating polarity; the second plurality of magnets are arranged on the base with alternating polarities; the first plurality of magnets are arranged to limit the angular rotation of the rotor with poles of the second plurality of magnets facing like poles of the first plurality of magnets; The system of claim 3.

9. The system of claim 3 , further comprising an angular encoder positioned to measure an angle of rotation of the rotor.

10. The system of claim 3 , wherein the mirror has a width of 1 cm or greater.

11. The system of claim 3 , wherein the first magnet and the second magnet are rare earth magnets.

12. The system of claim 3 , wherein the first magnet is mounted parallel to the mirror.

13. A routing mirror; a memory device comprising instructions that, when executed by one or more processors, adjust the routing mirrors to correct for scan position errors; The system of claim 3 further comprising:

14. rotating a rotor about a pivot using one or more bearings, the mirror being coupled to the rotor; emitting light from a laser towards the mirror; using the mirror to reflect light from the laser while the mirror rotates with the rotor; restricting rotation of the rotor using a first magnet and a second magnet, the first magnet coupled to the rotor and the second magnet coupled to a base, the second magnet positioned to restrict angular rotation of the rotor with poles of the second magnet facing like poles of the first magnet; 4. A method for using a vibrating mirror, comprising:

15. the laser is a first laser, the mirror is a first mirror, The method further comprising: emitting light from the first laser toward the first mirror and simultaneously emitting light from a second laser toward a second mirror; reflecting light from the second laser using the second mirror while the second mirror rotates with the rotor; Further comprising: the second mirror is coupled to the rotor; The method of claim 14.

16. the rotor comprises a body surrounding the pivot; the rotor includes legs extending from the body; the first magnet is coupled to the leg of the rotor; the method further comprising the step of limiting rotation of the rotor by limiting movement of the legs of the rotor. The method of claim 14.

17. the base includes a first bumper; the second magnet is coupled to the first bumper; the base further comprises a second bumper; the method further comprising using a third magnet coupled to the second bumper to limit angular rotation of the rotor in a direction opposite to that in which the first bumper limits rotation. The method of claim 14.

18. the first magnet is part of a first plurality of magnets coupled to the rotor; the second magnet is part of a second plurality of magnets coupled to the base; the first plurality of magnets are arranged on the rotor with alternating polarity; the second plurality of magnets are arranged on the base with alternating polarities; the first plurality of magnets are arranged to limit the angular rotation of the rotor with poles of the second plurality of magnets facing like poles of the first plurality of magnets; The method of claim 14.

19. The method of claim 14 further comprising the step of measuring an angle of rotation of the rotor using an angle encoder.

20. The method of claim 14 , wherein the mirror has a width of 1 cm or greater.

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