Modern vehicles are often equipped with sensors designed to detect objects and landscape features around the vehicle in real-time to enable technologies such as lane change assistance, collision avoidance, and autonomous driving. A commonly used sensor is a light detection and ranging (LiDAR) system.
A LiDAR system may include a light source, also referred to as a transmission module, and a light detection system, also referred to as a receiver module, to estimate distances to environmental features (e.g., pedestrians, vehicles, structures, plants, etc.). The transmission module may include a laser module and an optical lens assembly. The laser module may include a circuit board mounted laser configured to emit a laser beam that is optically aligned with the optical lens assembly. The emitted laser beam is used to illuminate a target and the LiDAR system measures the time it takes for the transmitted laser beam to arrive at the target and then return to the receiver module. In some LiDAR systems, the laser beam may be steered across a region of interest according to a scanning pattern to generate a “point cloud” that includes a collection of data points corresponding to target points in the region of interest. The data points in the point cloud may be dynamically and continuously updated, and may be used to estimate, for example, a distance, dimension, and location of an object relative to the LiDAR system, often with very high fidelity (e.g., within about 5 cm) due to the precision of the optical alignment of the components.
In embodiments, the present technology includes a method of assembling an optical module of a LiDAR system. The method may include providing a frame. The frame may include a base, a front left pillar extending from the base, a front right pillar extending from the base, a rear left pillar extending from the base, a rear right pillar extending from the base, a top front beam extending between the front left pillar and the front right pillar, a rear front beam extending between the rear left pillar and the rear right pillar a top left beam extending between the front left pillar and the rear left pillar, and a top right beam extending between the front right pillar and the rear right pillar, wherein the frame is monolithic. The method may further include fixedly coupling a front plate to the base and the top front beam so that the front plate contacts the front left pillar. The method may further include fixedly coupling a rear plate to the base and the top right beam, wherein the frame, the front plate and the rear plate define a support structure. The method may further include slidably coupling a transmission module to the support structure, wherein the slidable coupling restrains the transmission module to the support structure in five degrees of freedom, and wherein the transmission module comprises a chassis, a laser module and an optical lens module. The method may further include securing the chassis to at least one of the front plate and the rear plate with a first fastener so that the first fastener and the slidable coupling restrain the transmission module to the support structure in six degrees of freedom.
In embodiments, the front plate may include a first groove facing the rear plate, and the chassis of the transmission module may include a front rail. In embodiments, slidably coupling the transmission module to the support structure may include slidably engaging the front rail with the first groove. In embodiments, the rear plate may include a second groove facing the front plate, the chassis of the transmission module may include a rear rail, and slidably coupling the transmission module to the support structure may include slidably engaging the rear rail with the second groove.
In embodiments, the front plate may include a third groove facing the rear plate, and the rear plate may include a fourth groove facing the front plate. In embodiments, the method may include slidably coupling a second transmission module to the support structure by engaging a second front rail of the second transmission module with the third groove and engaging a second rear rail of the second transmission module with the fourth groove. In embodiments, the LiDAR system may include a galvanometer mirror assembly, the base may include a central mounting block coupled to the galvanometer mirror assembly, and the rear plate may include a faceted recess. The coupling of the rear plate to the frame may include engaging the faceted recess with side surfaces of the central mounting block.
In embodiments, a light transmission opening may be defined between the front plate, the base, the front right pillar, and the top front beam. The central mounting block and the galvanometer mirror assembly may be positioned so that a laser beam emitted from the transmission module reflects off the galvanometer mirror assembly and through the light transmission opening.
In embodiments, the frame may include a left mounting block extending from the base and the rear left pillar, and a right mounting block extending from the base and the rear right pillar. A left side of the rear plate may be coupled to the left mounting block with a second fastener and a right side of the rear plate is coupled to the right mounting block with a third fastener, so that a bottom side of the rear plate contacts the base. The left side of the rear plate may be coupled to the top left beam with a fourth fastener and the right side of the rear plate may be coupled to the top right beam with a fifth fastener.
In embodiments, the base of the frame may define a first slot and a second slot, and coupling the front plate to the frame may include positioning a first bracket in the first slot and a second bracket in the second slot, and coupling the front plate to the first bracket with a sixth fastener and to the second bracket with a seventh fastener so that a bottom side of the front plate contacts the base and a left side of the front plate contacts the front left pillar. In embodiments, coupling the front plate to the frame further may include coupling a top side of the front plate to the top front beam with an eighth fastener so that a top side of the front plate contacts the top front beam.
In embodiments, an optical module of a LiDAR system may include a frame comprising a base, a front left pillar extending from the base, a front right pillar extending from the base, a rear left pillar extending from the base, a rear right pillar extending from the base, a top front beam extending between the front left pillar and the front right pillar, a rear front beam extending between the rear left pillar and the rear right pillar, a top left beam extending between the front left pillar and the rear left pillar, and a top right beam extending between the front right pillar and the rear right pillar. The frame may be monolithic. The optical module may further include a front plate coupled to the base and the top front beam so that the front plate contacts the front left pillar, and a rear plate coupled to the base and the top right beam. The frame, the front plate and the rear plate may define a support structure. The optical module may further include a transmission module including a chassis, a laser module and an optical lens module. The transmission module may be slidably coupled to the support structure so that the slidable coupling restrains the transmission module to the support structure in five degrees of freedom, and the chassis of the transmission module may be secured to at least one of the front plate and the rear plate with a first fastener so that the first fastener and the slidable coupling restrain the transmission module to the support structure in six degrees of freedom.
In embodiments, the front plate of the optical module may include a first groove facing the rear plate, the chassis of the transmission module may include a front rail, and the slidable coupling may include the front rail engaging with the first groove. The rear plate may include a second groove facing the front plate, the chassis of the transmission module may include a rear rail, and the slidable coupling may include the rear rail engaging with the second groove. The optical module may include a second transmission module, the front plate may include a third groove facing the rear plate, the rear plate may include a fourth groove facing the front plate, and the second transmission module may be slidably coupled to the support structure by a second front rail of the second transmission module engaging with the third groove and a second rear rail of the second transmission module engaging with the fourth groove.
In embodiments, an optical module may include a galvanometer mirror assembly, the base may include a central mounting block coupled to the galvanometer mirror assembly, the rear plate may include a faceted recess, and the faceted recess may engage with side surfaces of the central mounting block. A light transmission opening may be defined between the front plate, the base, the front right pillar, and the top front beam. The central mounting block and the galvanometer mirror assembly may be positioned so that a laser beam emitted from the transmission module reflects off the galvanometer mirror assembly and through the light transmission opening.
In embodiments, the frame may include a left mounting block extending from the base and the rear left pillar, and a right mounting block extending from the base and the rear right pillar. A left side of the rear plate may be coupled to the left mounting block with a second fastener and a right side of the rear plate is coupled to the right mounting block with a third fastener, so that a bottom side of the rear plate contacts the base. The left side of the rear plate may be coupled to the top left beam with a fourth fastener and the right side of the rear plate may be coupled to the top right beam with a fifth fastener.
This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. The subject matter should be understood by reference to appropriate portions of the entire specification of this disclosure, any or all drawings, and each claim.
The foregoing, together with other features and examples, will be described in more detail below in the following specification, claims, and accompanying drawings.
The features of the various embodiments described above, as well as other features and advantages of certain embodiments of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:
Throughout the drawings, it should be noted that like reference numbers are typically used to depict the same or similar elements, features, and structures.
Aspects of the present disclosure relate generally to securing optical components to a frame. The frame and optical components may be part of a LiDAR system, according to certain embodiments.
In the following description, various examples of securing optical components to a frame are described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the embodiments. However, it will be apparent to one skilled in the art that certain embodiments may be practiced or implemented without every detail disclosed. Furthermore, well-known features may be omitted or simplified in order to prevent any obfuscation of the novel features described herein.
The following high-level summary is intended to provide a basic understanding of some of the novel innovations depicted in the figures and presented in the corresponding descriptions provided below. Generally, aspects of the invention are directed to implementations of fixedly coupling optical components, for example a transmission module (TX) or combination transmission and receiver module (TX/RX) to a support structure so that the optical components are optically aligned with each other. The optical components of a LiDAR system are precisely optically aligned in order for the LiDAR to makes accurate measurements, particularly at longer ranges. In order to maintain optical alignment between optical components that are used together, the optical components may be fixedly coupled to a common support structure in order to restrain movement in the six degrees of freedom, i.e. XYZ translation and XYZ rotation. One method of fixedly coupling an optical component to a support structure is to use one or more fasteners, e.g. screws/bolts, to clamp the optical component against the support structure. The one or more fasteners may be the primary means for restraining movement in the six degrees of freedom. One disadvantage of using fasteners as the primary means for restraint is that fasteners may require an exact torque to achieve and maintain optical alignment. For example, over or under tightening a fastener may cause the coupled components to shift from optically aligned to not optically aligned. Further, due to various manufacturing tolerances of the different components, e.g. optical components, fasteners and the support structure, the exact torque needed for optical alignment may be unique to a particular combination of components. Therefore, achieving optical alignment may be a time consuming task of applying many combinations of different torques to the multiple fasteners in order to determine a combination that leads to optical alignment of all of the components. This process may need to be performed during the assembly of each optical assembly since a combination of torques leading to optical alignment in one optical assembly may be different than a combination of torques leading to optical alignment in another optical assembly due to minor differences in the components, for example due to manufacturing tolerances.
The present technology relates to securing a transmission module (TX) or combination transmission and receiver module (TX/RX) to a support structure, wherein fasteners are not the primary means of restraint for coupling the components together. Specifically, the support structure comprises a frame, for example as shown in
As shown in
The optical assembly 100 may further comprise one or more circuit boards 102 coupled to the frame 200. The circuit boards 102 may be electrically coupled to one or more of the transmission module 700, the galvanometer mirror assembly 101, other circuit boards 102, or other components in the LiDAR system.
As shown, with a rectangular base 201, the four pillars 202, 203, 208 and 209 extend away from the base proximate to respective corners of the base 201. Further, the four beams 205, 206, 207 and 208, connect the ends of the pillars 202, 203, 208 and 209 opposite the base 201. Specifically, the top left beam 205 extends between the rear left pillar 208 and the front left pillar 202. The front top beam 204 extends between the front left pillar 202 and the front right pillar 203. The top right beam 206 extends between the front right pillar 203 and the rear right pillar 209. The rear top beam 207 extends between the rear right pillar 209 and the rear left pillar 208.
As shown, the base 201 and frame elements define a rectangular prism comprising one closed side at the base 201, and five open sides. The open sides define generally rectangular openings. As shown in
As shown in
The top left beam 205 defines an outer surface facing away from the center of the frame and an inner surface facing toward the center of the frame. A hole 216 may extend between the outer surface and the inner surface for receiving a fastener 217 to couple the rear plate 300 to the frame 200. The top right beam 206 defines an outer surface facing away from the center of the frame and an inner surface facing toward the center of the frame. A hole 218 may extend between the outer surface and the inner surface for receiving a fastener 219 to couple the rear plate 300 to the frame 200.
The front top beam 204 defines a top surface facing away from the base of the frame 200 and a bottom surface facing toward the base 201 of the frame 200. One or holes 220 may extend between the top surface and the bottom surface for receiving a fastener 221 to couple the front plate 500 to the frame 200. As shown in
The base 201 defines a plurality of slots 223 extending from the bottom side to the top side of the base 201 for receiving brackets 224 used to receive fasteners 225 to couple components to the frame. The frame 200 may further comprise a central mounting block 226 extending from the base 201 toward the top side for mounting a galvanometer mirror assembly 101 as shown for example in
In order to provide structural support, the frame 200 may be monolithic, and may be formed of a rigid material, such as aluminum, via machining, casting, or a combination thereof.
As shown in
As shown in
The front face 301 of the rear plate further comprises a groove 311. In embodiments, the groove 311 may be rectangular and extend between the recess 310 and the left side 305. As will be discussed in greater detail below, the groove 311 may slidably engage with a portion of the transmission module 700 in order to slidably couple the transmission to the support structure comprising the frame 200, rear plate 300, and front plate 500. The groove may comprise a hole 312 proximate to the recess 310. Further, the left side 305 may comprise a hole 313. Holes 312 and 313 may be used to receive fasteners used to prevent the transmission module 700 from sliding out of the groove 311. In embodiments, the front face 301 may comprise additional grooves parallel to groove 311 for slidably coupling multiple transmission modules 700 to the support structure.
As shown in
The rear face 506 of the front plate 500 further comprises a groove 511. In embodiments, the groove 511 may be rectangular and extend between the right side 503 and the left side 505. As will be discussed in greater detail below, the groove 511 may slidably engage with a portion of the transmission module 700 in order to slidably couple the transmission to the support structure comprising the frame 200, rear plate 300, and front plate 500. The groove 511 may comprise holes 512 proximate to ends of the groove 511. Holes 512 may be used to receive fasteners 516 used to prevent the transmission module 700 from sliding out of the groove 511. In embodiments, the rear face 506 of the front plate 500 may comprise additional grooves 514 parallel to groove 511 for slidably coupling multiple transmission modules 700 to the support structure. The front plate 500 may comprise a plurality of elongated slot 515 in order to provide surface area heat dissipation, for example to dissipate heat generated by a laser of a transmission module 700.
Other variations are within the spirit of the present disclosure. Thus, while the disclosed techniques are susceptible to various modifications and alternative constructions, certain illustrated examples thereof are shown in the drawings and have been described above in detail. It should be understood, however, that there is no intention to limit the disclosure to the specific form or forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions and equivalents falling within the spirit and scope of the disclosure, as defined in the appended claims. For instance, any of the examples, alternative examples, etc., and the concepts thereof may be applied to any other examples described and/or within the spirit and scope of the disclosure.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the disclosed examples (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. The phrase “based on” should be understood to be open-ended, and not limiting in any way, and is intended to be interpreted or otherwise read as “based at least in part on,” where appropriate. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate examples of the disclosure and does not pose a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.