Sensor head assembly having opposing sensor configuration with mount

An optical sensor assembly including a housing structure, a first optical sensor secured to the housing structure and arranged to sense in a first direction and a second optical sensor secured to the housing structure and arranged to sense in a second direction opposite to the first direction.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The present disclosure is directed to a sensor head assembly having a compact rotating assembly that avoids optical interferences, a sensor mounting apparatus having a rigid skeletal structure, and an optical sensor enclosure with improved ingress and egress of airflow for cooling and cleaning.

2. Description of the Related Art

Autonomous vehicles AVs) use a plurality of sensors for situational awareness. The sensors, which can be part of a self-driving system SDS) in the AV, include one or more of a camera, lidar (Light Detection and Ranging) device, inertial measurement unit (IMU), etc. The sensors such as cameras and lidar are used to capture and analyze scenes around the AV to detect objects including static objects such as fixed construction(s), and dynamic objects such as pedestrians and vehicles. Data from such sensors can also be used to detect conditions, such as road markings, lane curvature, traffic lights and signs, etc. In addition, a scene representation such as 3D point cloud obtained from the AVs lidar can be combined with images from cameras to obtain further insight about the scene or situation around the AV.

In addition, a lidar sensor operating on an AV includes a transceiver apparatus including a transmitter and receiver assembly. the transmitter transmits a light signal and the receiver receives and processes the received light signal. To provide high fidelity object detection and tracking, an optical sensor such as lidar, includes rigidly fixed optical components and sufficient spacing for one or more transceiver assemblies, processing and driver circuitry, cooling elements, cleaning elements, wiring, and associated motor assemblies. The lidar can also have the transceiver components rigidly fixed with respect to each other to withstand automotive grade vibrations, high speed rotations for mechanical lidar assemblies, and address balance and weight considerations. Additionally, the lidar needs sufficient accommodation packaging and needs to consider aesthetic considerations.

SUMMARY OF THE DISCLOSURE

Accordingly, an object of the present invention is to address the above-noted and other problems.

Another object of the present disclosure is to provide improvements in inertia mass effects of the optical sensor during rotation so the center of gravity of the respective optical devices are positioned to be substantially diametrically opposite one another relative to a center of rotation.

Still another object of the present disclosure is to provide a sensor mounting apparatus having a rigid structure, which enables the modular attachment of components, such as cooling elements, window elements, cleaning elements, and the like, accommodate space considerations, and provide sufficient sealing from external and weather elements.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, the present invention provides in one aspect an optical apparatus including a pair of optical sensors oriented in opposing directions to provide a compact rotating assembly. The minimization of size improves weight, aerodynamic drag, and/or wind noise during high-speed movement.

In another aspect, the present disclosure provides a plurality of optical sensors nested with respect to each other so the field of view of each of the respective optical sensors is substantially diametrically opposed to one another (e.g., opposite to one another). Each sensor can differ in performance specifications and/or operational purpose. For example, a plurality of sensors having differing range capabilities can be provided. Positioning at least a pair of optical sensors in this fashion improves packaging efficiency for the sensor head assembly. In another example, more than two sensors can be positioned with respect to one another, with each of the multiple sensors having a substantially divergent field of view with respect to the other optical sensors.

Further, each sensor can be juxtaposed to a sidewall of an outer housing of the lidar sensor assembly. In addition, thermal heat sinks are provided within the outer housing. The thermal heat sinks absorb and dissipate heat generated by the optical sensors during operation. In one example, a thermal heat sink apparatus is disposed about a rear portion of each of the respective optical sensors, opposite a front lens portion. Each heat sink can have a shape corresponding to a cylindrical shape of the outer housing, can be disposed adjacent to a first window and concurrently remain in contact with the rear portion of the opposing optical sensor directed away from the first window.

Advantages of the present disclosure include the avoidance of optical interference, or crosstalk, between the two or more optical sensors. When the optical sensors are disposed with an overlapping field of view, light return resulting from an emission of a first optical sensor can be received by the second optical device and cause errors in range detection, etc. Conversely, arranging the optical devices in opposing direction avoids optical interference altogether between the two sensors (e.g., the two separate transceivers).

The present disclosure also includes improvements in inertia mass effects during rotation. That is, the center of gravity of the respective optical devices can be positioned to be substantially diametrically opposite one another relative to a center of rotation.

In still another aspect, the present disclosure provides a mounting apparatus for an optical sensor includes a skeletal assembly comprising six facia. The individual fascia include structural features to receive one or more components of the sensor assembly. For example, one or more of the six facia are configured to receive modular cooling elements. Similarly, one or more of the six facia are configured to receive a modular detachable optical window. One or more of the six facia can also be configured to rigidly secure one or more transceiver assemblies of the optical sensor. Therefore, the mounting apparatus is flexibly configured to accept a plurality of different component types and provide a rigid mounting structure.

Thus, the present disclosure provides a sensor mounting apparatus that provides rigid structure, enables the modular attachment of components, such as cooling elements, window elements, cleaning elements, and the like, accommodate space considerations, and provide sufficient sealing from external and weather elements.

In still another aspect, the present disclosure provides a lidar sensor system including a housing for containing electronics, optical elements, cooling elements and architectural or structural elements designed to hold such components into place. An enclosure is provided to provide functional and aesthetic solutions to the lidar sensor system and can be designed to maximize ingress and egress of airflow for cooling and cleaning purposes. The enclosure can also provide an aerodynamic housing for the lidar sensor system.

Further scope of applicability of the disclosure will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating embodiments of the disclosure, are given by way of illustration only, since various changes and modifications within the scope of the disclosure will become apparent to those skilled in the art from this detailed description.

DETAILED DESCRIPTION OF THE DISCLOSURE

The present disclosure will now be described with reference to the accompanying drawings, wherein the same reference numerals have been used to identify the same or similar elements throughout the several views.

FIG.1is a side perspective view of a sensor head1mounted to a rotating platform10. As shown, the sensor head1includes two opposing sensors5,6(FIG.2), having a different field of view, to avoid risk of a light return resulting from an emission of a first optical sensor5being received by the second optical device6and causing errors in range detection, etc. The sensor head1includes a window3(e.g., channel) for each sensor5,6(e.g., a single window for each sensor), and the window3can be for Tx (transmitter) optics and Rx (receiver) optics. In more detail, the Tx optics refer to an output power of a transceiver apparatus (e.g., sensor device), which can be a lidar transceiver apparatus. The Rx optics refer to a receiver assembly of the lidar assembly, and that receives the transmitted signal as well as stray light and other light signals. Further, the Rx optics can include a lens assembly, as shown inFIG.2.

FIG.1also illustrates a rotating platform10including flanges12that can be attached to a fixed surface, such as a table via fasteners12. The fasteners12can be screws, bolts, nails or the like. The rotating platform10can be attached to the bottom surface of the sensor head1by fasteners and the like, and can be removably attached to the sensor head1. Further, the rotating platform10includes a top member13having bearings, which allow the rotating platform10to be rotatable with respect to the sensor head1. Therefore, the sensor head1can rotate about the rotating platform10via the bearings.

In addition, the sensor head1can further include a heat sink4(e.g., thermal sink) on opposing sides of the sensor head1. In particular, the heat sinks4cool the optical sensors5,6to ensure they operate within predefined temperature conditions. Each heat sink4can be disposed at a rear portion of each of the optical sensor5,6. Each heat sink4can also have a curvature to match a curvature of an outer housing2of the sensor head1, and be disposed adjacent to a corresponding window3and concurrently remain in contact with a rear portion of the corresponding optical sensor5,6. Further, each heat sink4can be in contact with, or be spaced from, the outer housing2of the sensor head1.

Next,FIG.2is a top perspective view of the sensor head ofFIG.1, showing a pair of sensors5,6disposed in opposing directions. The optical sensors5,6can be directed away from one another, such that they are oriented 180° from one another. This opposing orientation of the optical sensors5,6limits potential optical interference, or crosstalk, between the optical sensors5,6. Each optical sensor5,6can be a lidar device, such that the sensor head1of the present disclosure can accommodate two separate lidar devices. However, additional lidar devices can be present within the sensor head, with a corresponding number of windows. When more than two lidar devices are present, they can be oriented at different angles relative to a cross-sectional center of the sensor head1.

According to an embodiment of the present disclosure, a plurality of optical sensors5,6can be positioned with respect to each other so the field of view of each of the respective optical sensors5,6is substantially diametrically opposed to one another. More specifically, each of the optical sensors5,6can differ in performance specifications and/or operational purpose including having differing range capabilities. The optical sensors5,6can be positioned as shown in the figures to improve packaging efficiency for the sensor head1. In further examples, more than two sensors can be positioned within the sensor head1with respect to one another, where each of the multiple sensors has a substantially divergent field of view with respect to the other optical sensors. Each sensor also can include a transceiver including an optical transmitter and receiver.

Next,FIG.3is a top perspective view of the sensor head ofFIG.1, showing a sensor head1with and without an outer housing2. The heat sink4is shown having a curvature matching the curvature of the outer housing2. The sensor head1can be provided with a lid7, and the lid7can be provided with a seal facing a surface (e.g., top surface) of the sensor head1, such as a rubber seal, to weatherproof the sensor head1. Further, the lid7can be adhesively bonded to a surface of the sensor head1. Also, the window3and the heat sink4can be attached to plate8, such as by fasteners, and the heat sink4can also be detachable from the plate8. Alternatively, the heat sink4and the plate8can be simultaneously formed together, such as by casting, extrusion, machining, or the like. The heat sinks4can also be provided at front and rear surfaces of the sensor head1, and additional heat sinks4S can be provided on the left and right surfaces of the sensor head1, to provide additional heat dissipation. The additional heat sinks4S can have a rectangular shape, and can accommodate a majority of a side of the sensor head1to maximize heat dissipation. Further, each additional heat sink4S can be part of a corresponding one of the sensors5,6, such that the sensor5,6and the corresponding heat sink4S represent a single module, as shown inFIG.4.

In more detail,FIG.4is an exploded view of the sensor head ofFIG.1, showing a frame9of the sensor head1. Each of the sensors5,6, can be attached to the frame9by fasteners, for example. As shown inFIG.4, the frame9can have a cuboid shape with hollow walls at each face for insertion and assembly of the sensors5,6to the frame9. The sensor head1can include a base plate11, which includes protrusions11A for locating the sensors5,6. That is, the sensors5,6can include a groove that corresponds to one of the protrusions11A.

Next,FIG.5is a top cross-sectional view of the sensor head ofFIG.1,FIG.6is a top cross-sectional view of the sensor head ofFIG.5, showing a light projection of the opposing sensors, andFIG.7is a top cross-sectional view of a sensor head having alternate sensors with modified sensor channels. As shown inFIGS.5-7, the sensors5,6are arranged to face opposite directions, which allows for a less clearance within the sensor head1, thereby providing a more efficient packaging and minimizing the size of the sensor head1.

FIG.6illustrates a cross-sectional center C of the sensor head1. X1 represents a distance, in an X-direction, between a center of a second sensor6and the cross-sectional center C; X2 represents a distance, in an X-direction, between a center of a first sensor5and the cross-sectional center C; Y1 represents a distance, in a Y-direction, between a center of a second sensor6and the cross-sectional center C; and Y2 represents a distance, in a Y-direction, between a center of a first sensor5and the cross-sectional center C.FIG.7shows arrows representing the transmission of light and receiving light at each of the windows3of the optical sensors5,6.

Next,FIG.8is a side cross-sectional view of the sensor head illustrating the sensor head ofFIG.1including tiltable sensors. The optical sensors5,6can be tiltable in a vertical direction (e.g., Z-direction that is perpendicular to the X-direction and the Y-direction set forth above). Each optical sensor5,6can have a varying degree of tilt, such that a first sensor5can tilt more or less than a second sensor6, as shown inFIG.8.

FIG.9is a top perspective view of the sensor head ofFIG.1, showing a rim outer cover15andFIG.10is a top perspective view of the sensor head ofFIG.1, showing interior rim parts to block bypass air flow. The rim outer cover15includes two cover windows16at a location corresponding to the windows3of the optical sensors5,6. The two cover windows16and two side covers17constitute interior rim parts that block bypass air flow.

In addition,FIG.11is a top perspective view of the sensor head ofFIG.1, provided without interior rim parts, showing channels (e.g., windows3) of the optical sensors5,6. The sensor head1can be sealed when attached to the rotating platform10, and be waterproof and protected from dust to a certain degree. For example, the sensor head1can have an IP67 protection code.

Next,FIG.12is an exploded view of the of the sensor head according to an embodiment of the present disclosure, andFIG.13is a cross-sectional view of the sensor head ofFIG.12.FIGS.12and13are provided with a differently shaped base plate11having various protrusions/flanges11B. The frame9can be provided with seals9A, such as rubber seals, polyurethane seals, or the like, at each mating surface (e.g., each surface facing outwards). Further, each optical sensor5,6can be provided with a plurality of heat sinks4S disposed at a side surface thereof.

FIG.14is an exploded view of the of a sensor head according to an embodiment of the present disclosure, illustrating a plurality of sealing surfaces9A, and the frame9having a plurality of protrusions9B, with fastening holes for attaching to a base or to an outer cover. In addition,FIGS.15and16are side perspective views of a lidar assembly50including a FPGA mounting apparatus according to an embodiment of the present disclosure. For example, the FPGA mounting apparatus60(i.e., the FPGA mounting apparatus) can secure an FPGA module70, a laser module80(e.g., laser driver), Tx (transmit) optics90, a transceiver interface board (e.g., circuit board)100, to a sidewall of lidar assembly50. The mounting apparatus60can be attached to the circuit board100. Further, the lidar assembly50can include a side plate assembly51, which can include a first side plate52and a second side plate53, which is attached to the mounting apparatus60.

In addition, the Tx optics90refers to an output power of the Lidar transceiver. The mounting apparatus60may further include a frame61and other features to accommodate a variable alignment of the electronic device. For example, the mounting apparatus60can include a module mounting structure63having a hole (a through-hole) to accommodate the FPGA module70, and the module mounting structure63can be movable in multiple axes to accommodate movement of the FPGA module70(e.g., to allow for proper alignment of the FPGA module70). The module mounting structure63can be mounted to the frame61of the mounting apparatus60via fasteners63A extending through holes (e.g., apertures, threaded apertures or holes, etc.) of the module mounting structure63and the holes of the module mounting structure63can be elongated and larger (i.e., have a larger cross-section) than the fasteners to allow for movement of the module mounting structure63relative to the mounting apparatus60. An Li-shaped structure (or L-shaped structure) is shown as oriented laterally and vertically and is provided to secure an optical electronic subcomponent (e.g., the FPGA module70or the like, such as any component of a lidar assembly).

The FPGA module70can include a circuit board72and Rx optics. Rx optics refer to a receiver assembly of the lidar assembly50, and the receiver assembly can receive the transmitted signal as well as stray light and other light signals. Further, the Rx optics can include a lens assembly, as shown inFIGS.15and16.

According to more specific aspects, the mounting apparatus60can be provided with a skeleton frame to minimize mass yet still provide structural rigidity in desired regions. A skeleton frame refers to a frame having holes (e.g., through-holes) or apertures62, as shown inFIGS.15and16. The holes62can have any dimension (e.g., size and shape), and the mounting apparatus60shown inFIGS.15and16includes multiple holes62with multiple dimensions to reduce weight of the mounting apparatus60. Further, the mounting apparatus60can include protrusions65, which include holes for receiving a fastener, in order to attach the circuit board100to the mounting apparatus60.

According to another aspect of the present disclosure, the FPGA mounting apparatus60can include a heat-conductive material, such as any type of metal, to transfer heat to walls that are exposed. Additionally, the mounting apparatus60can be connected to cooling fins4S and the like, which allows for heat transfer from the FPGA module70to ambient air, thereby providing additional cooling capacity. According to some aspects, the FPGA mounting apparatus60can be made of an iron alloy, and aluminum alloy, a magnesium alloy, or the like to help provide reliable structural alignment at manufacturing.

Additionally, the mounting apparatus60can further include a fan to direct forced air across an external portion of a sidewall52,53(e.g., the wall onto which the laser module80is attached to, as shown inFIGS.15and16) to divert waste heat generated by electronic components. According to some aspects, the FPGA mounting apparatus60can also serve as a stabilizing mount for other electronic circuitry, such as laser driver circuits80, focal plane array circuitry and the like.

In addition, the disclosed assembly and orientation provides additional benefits for an optical sensor/system such as the disclosed lidar system. The opposite direction orientation of the sensors provides for an assembly/housing structure that can provide enhanced thermal stability/profile. For example, the disclosed structure can accommodate cooling systems, fans, and associated air ducts that can provide better thermal performance. Additionally, the space created by such orientation allows for improved accommodation of wiring harnesses, processing circuitry, and sealing components.

FIG.17is a perspective view of an optical sensor enclosure200according to an embodiment of the present disclosure,FIG.18is a perspective view of an optical sensor enclosure according to an embodiment of the present disclosure,FIG.19is a perspective view of an optical sensor enclosure showing fastening location(s),FIG.20is a perspective view of an optical sensor enclosure showing other fastening location(s), andFIG.21is a bottom perspective view of an optical sensor enclosure without the optical sensor.

The optical sensor enclosure200includes an outer cover210which has one or more holes for accommodating one or more sensor windows220. Further, the optical sensor enclosure200includes a top plate230that is fastened to the outer cover210via a plurality of fasteners215at a plurality of fastening locations217. There can be eight (8) fixed fastening locations217, as shown inFIG.21. Further, the outer cover210can include one or more perforations219(e.g., holes extending through an entire thickness of the out cover to allow air to pass from an interior of the outer cover210to an exterior of the outer cover210). The perforations219can have a plurality of different sizes and can be distributed at certain locations of the outer cover210, including at locations corresponding to a location of optical sensors.FIG.20illustrates the sensor window220attached to the outer210via a fastener. Further, the optical sensor enclosure200can accommodate a plurality of optical sensors, such that it is provided with multiple sensor windows220, as shown inFIG.21.

Also, the enclosure mounted on a base of the lidar sensor system improves the performance of the lidar system. In one example, the enclosure can be mounted using underside fasteners leading to improved aerodynamic qualities (as opposed to exposed external fasteners) as well as improve the mass balance distribution of the overall lidar sensor system.

According to some examples of the present disclosure, a series of fasteners securing an outer cover can be secured from beneath such that the fastener heads are not in wind flow regions. The fastener heads are also less visible or fully hidden to external viewers, thus improving the aesthetics of the external appearance of the lidar device. More specifically, at least one of the securing fasteners can be disposed within a recess formation associated with the lidar lens to provide a tool access angle (for example, as shown by dashed arrow in the right figure above) to secure the fastener once the housing is placed on the device.

In addition, the optical sensor enclosure can be formed of material improving heat dissipation as well as detectability by other sensors.