Patent Publication Number: US-2023161005-A1

Title: Cleaning and cooling of vehicle sensor assembly

Description:
BACKGROUND 
     A vehicle may include a system or systems for autonomously or semi-autonomously operating the vehicle, e.g., an advanced driver assist system ADAS for speed control, lane-keeping, rooftop sensor assemblies, etc. In examples where the vehicle includes a rooftop sensor assembly, the rooftop sensor assembly may include sensors that may have a field of view around the vehicle. The rooftop sensor assembly may clean and cool the sensors with fluid and air to ensure integrity of data collected by the sensors such that the vehicle continues to operate properly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of a vehicle having an assembly for vehicle sensors supported by a roof of the vehicle. 
         FIG.  2    is an exploded view of the assembly having a sensor assembly and a sensor housing. 
         FIG.  3    is a view of a bottom of the sensor assembly. 
         FIG.  4    is a cross-sectional view of a first example embodiment of the assembly through line  4  of  FIG.  1   . 
         FIG.  5    is a cross-sectional view of a second example embodiment of the assembly through line  4  of  FIG.  1   . 
         FIG.  6    is a cross-sectional view of a third example embodiment of the assembly through line  4  of  FIG.  1   . 
     
    
    
     DETAILED DESCRIPTION 
     An assembly includes a sensor housing defining an inlet. The assembly includes a sensor assembly rotatably supported by the sensor housing. The sensor assembly includes a sensor and a cover surrounding the sensor. The sensor assembly includes a cavity between the sensor and the cover. The inlet is in fluid communication with the cavity. 
     The sensor housing may define a channel extending from the inlet to the cavity, the inlet being in fluid communication with the cavity through the channel. 
     The inlet and the channel may define an air flowpath from the inlet to the cavity. 
     The sensor may be elongated along an axis, at least a portion of the air flowpath extending along the axis. 
     The sensor housing may define an outlet aimed at the sensor assembly, the inlet being in fluid communication with the outlet. 
     The sensor housing may define a first channel and a second channel, the first channel extending from the inlet to the cavity and the second channel extending from the inlet to the outlet. 
     The inlet and the first channel may define a first air flowpath from the inlet to the cavity and the inlet and the second channel define a second air flowpath from the inlet to the outlet. 
     The second air flowpath may extend adjacent the sensor. 
     The sensor housing may define a wedge extending upwardly adjacent the outlet and vehicle-forward of the sensor. 
     The sensor housing may define an air flowpath exterior to the sensor housing along the wedge and adjacent the sensor. 
     The assembly may include a blower supported by the sensor housing at the inlet. 
     The cavity may extend continuously circumferentially about the sensor. 
     The inlet may be vehicle-forward of the sensor. 
     The sensor housing may be designed to be supported by a vehicle roof. 
     The inlet may be spaced upwardly from the vehicle roof. 
     The sensor may be a lidar sensor. 
     With reference to the Figures, wherein like numerals indicate like parts throughout the several views, an assembly  10  for a vehicle  12  includes a sensor housing  14  defining an inlet  16 . The assembly  10  includes a sensor assembly  18  rotatably supported by the sensor housing  14 . The sensor assembly  18  includes a sensor  20  and a cover  22  surrounding the sensor  20 . The sensor assembly  18  has a cavity  24  between the sensor  20  and the cover  22 . The inlet  16  is in fluid communication with the cavity  24 . 
     While the vehicle  12  is in motion, the assembly  10  utilizes the motion of the vehicle  12  and air generated from the vehicle  12  motion to clean and cool the sensor  20 . The inlet  16  may receive air from a front of the vehicle  12  as the vehicle  12  is in motion. The air received from the inlet  16  flows through the sensor housing  14  into the cavity  24  between the sensor  20  and the cover  22 . The air is used to cool the sensor  20  and to clean the sensor  20 , i.e., to remove debris collection (including, for example, water, insects, dirt, etc.) on the sensor  20  during use of the vehicle  12 . In some examples, the air is used to prevent debris from reaching the sensor  20 , i.e., operating as an air curtain. This air may surround the sensor  20  to cool and clean the sensor  20  while the vehicle  12  is in motion. 
     Three example embodiments are shown in the Figures and common numerals are used to identify common features in the example embodiments. One example embodiment of the assembly  10  is shown in  FIG.  4   . In such an example, the assembly  10  includes the inlet  16  and a channel  46  directing air from the channel  46  into the cavity  24  of the sensor assembly  18 . A second example embodiment of the assembly  10  is shown in  FIG.  5   . In such an example, the assembly  10  includes a blower  30  at the inlet  16  that supplements the air directed into the cavity  24  through the inlet  16 . A third example embodiment of the assembly  10  is shown in  FIG.  6   . In such an example, the assembly  10  includes a pair of channels  46 ,  48 . One of the channels  46  directs air into the cavity  24  of the sensor assembly  18  and the other of the channels  48  directs air to an outlet  40  that directs air outside of the sensor assembly  18 . The outlet  40  may act as an “air curtain” to the sensor assembly  18  for deflecting debris away from the sensor assembly  18 . 
     With reference to  FIG.  1   , the vehicle  12  may be any suitable type of automobile, e.g., a passenger or commercial automobile such as a sedan, a coupe, a truck, a sport utility, a crossover, a van, a minivan, a taxi, a bus, etc. The vehicle  12 , for example, may be autonomous. In other words, the vehicle  12  may be autonomously operated such that the vehicle  12  may be driven without constant attention from a driver, i.e., the vehicle  12  may be self-driving without human input. 
     In examples where the vehicle  12  is an autonomous vehicle, a computer (not numbered) may be programmed to operate the vehicle  12  independently of the intervention of a human driver, completely or to a lesser degree. The computer may be programmed to operate a propulsion system, brake system, steering, and/or other vehicle systems based at least in part on data received from the sensor  20 . For the purposes of this disclosure, autonomous operation means the computer controls the propulsion system, brake system, and steering system without input from a human driver; semi-autonomous operation means the computer controls one or two of the propulsion system, brake system, and steering system and a human driver controls the remainder; and nonautonomous operation means a human driver controls the propulsion system, brake system, and steering system. 
     The vehicle  12  may include a vehicle body  26 . The vehicle body  26  includes body panels at least partially defining an exterior of the vehicle  12 . The body panels may present a class-A surface, e.g., a finished surface exposed to view by a customer and free of unaesthetic blemishes and defects. The body panels include, e.g., a vehicle roof  28 , body side panels, etc. 
     The vehicle body  26  defines a passenger compartment (not numbered) to house occupants, if any, of the vehicle  12 . The passenger compartment may extend across the vehicle  12 , i.e., from one side to the other side of the vehicle  12 . The passenger compartment includes a front end and a rear end with the front end being in front of the rear end during forward movement of the vehicle  12 . 
     With continued reference to  FIG.  1   , the vehicle  12  includes one or more assemblies  10  supported by the vehicle roof  28 . For example, the assembly  10  is attached to the vehicle roof  28 . The assembly  10  may be supported by the roof to provide the sensor  20  with an unobstructed field of view of an area around the vehicle  12 . The assembly  10  includes the sensor housing  14  that may be designed to be supported by the vehicle roof  28 . As shown in the Figures, the sensor housing  14  is supported by the vehicle roof  28  above the passenger compartment and on the exterior of the vehicle  12 . The assembly  10  may extend upwardly from the vehicle roof  28  and is spaced between a front of the vehicle  12  and a rear of the vehicle  12  along a vehicle-longitudinal axis L. The sensor housing  14  may be secured to the vehicle roof  28  for when the vehicle  12  is in motion. In other words, the sensor housing  14  remains stationary relative to the vehicle roof  28  when the vehicle  12  is in motion. The sensor housing  14  may be secured to the vehicle roof  28  in any suitable way, e.g., fasteners, adhesive, magnets, etc. The sensor housing  14  may present a class-A surface on an exterior of the assembly  10 . The sensor housing  14  may enclose and protect operation components of the assembly  10 . For example, electrical wiring or other sensors may be housed inside the sensor housing  14 . The sensor housing  14  may be formed of, for example, plastic or metal. 
     With reference to  FIGS.  1 - 3   , the assembly  10  includes the sensor assembly  18 . The sensor assembly  18  may be supported by the sensor housing  14 . Specifically, the sensor assembly  18  may extend upwardly from the sensor housing  14 . The sensor assembly  18  may be designed to detect features of the outside world. Specifically, the sensor assembly  18  includes the sensor  20  and the sensor  20  detects features of the environment around the vehicle  12 . The sensor  20  may be a radar sensor, a scanning laser range finder, a light detection and ranging lidar device (lidar), or an image processing sensor such as a camera. In particular, as shown in the examples in the Figures, the sensor  20  is a lidar sensor, e.g., a scanning lidar sensor. In such an example, the lidar sensor detects distances to objects by emitting laser pulses at a particular wavelength and measuring the time of flight for the pulse to travel to the object and back. 
     With reference to  FIGS.  1 - 6   , the sensor assembly  18  includes the sensor  20  inside the cover  22 . The operation of the sensor assembly  18  is performed by the sensor  20  inside the cover  22 . The sensor assembly  18  is rotatably supported by the sensor housing  14 . The sensor assembly  18  may rotate relative to the sensor housing  14  when the vehicle  12  is in use to detect features of the outside world. In other words, the sensor assembly  18  rotates relative to the vehicle  12 . Both the sensor  20  and the cover  22  rotate relative to the vehicle  12  when the vehicle  12  is in use. The sensor  20  has fields of view through sensor windows  44  encompassing a region from which the sensor  20  receives input. As the sensor assembly  18  rotates, the fields of view encompass a horizontal 360 degrees around the vehicle  12 . 
     With reference to  FIGS.  2  and  3   , the sensor assembly  18  includes a base  32 . The base  32  is attached to the sensor housing  14  on a top of the sensor housing  14 . The base  32  may be bolted to the housing, e.g., through bolt holes in the base  32 . The sensor assembly  18  includes a motor (not shown). The motor is arranged to drivably rotate the sensor assembly  18 , i.e., the sensor  20  and the cover  22 , in the direction of rotation about an axis A. The motor may be positioned, e.g., inside the base  32 . The motor may be, e.g., an electric motor. 
     As discussed above, the sensor assembly  18  includes the cover  22 . In the example shown in the Figures, the cover  22  is cylindrical. Specifically, the cover  22  includes at least one wall  34 , e.g., a cylindrical wall  34 , and a top panel  36 . The top panel  36  extends horizontally to the wall  34 . In other examples, the cover  22  may be of any suitable shape. The sensor  20  is contained inside the cover  22 . Specifically, the cover  22  surrounds the sensor  20 . As discussed above, the cover  22  and the sensor  20  may both rotate relative to the sensor housing  14  when the vehicle  12  is in use. In other words, the sensor  20  and the cover  22  rotate as a unit when the vehicle  12  is in use. 
     The sensor assembly  18  may be elongated along the axis A. Specifically, in examples where the sensor  20  is a lidar sensor, such as shown in the Figures, the sensor  20  and the cover  22  are elongated along the axis A. In other words, as discussed above, the sensor assembly  18 , i.e., the sensor  20  and the cover  22 , extend upwardly from the sensor housing  14  along the axis A. 
     With reference to  FIGS.  4 - 6   , the sensor assembly  18  has a cavity  24  between the sensor  20  and the cover  22 . The cover  22  may be spaced from the sensor  20  by the cavity  24 , i.e., the cavity  24  is between the cover  22  and the sensor  20 . The cavity  24  extends continuously circumferentially about the sensor  20 . Specifically, the cavity  24  extends continuously circumferentially about the axis A. The term “continuously” in the context of this disclosure means that the cavity  24  is unbroken about the axis A and air may move freely within the cavity  24  and throughout the entire cavity  24 . The cavity  24  is elongated along the axis A upwardly from the sensor housing  14 . The cavity  24  may fill with air during forward travel of the vehicle  12  to circulate air around the sensor  20  to cool the sensor  20  and clean any debris that may collect on the sensor  20  during use of the vehicle  12 . 
     The sensor assembly  18  may include at least one sensor window  44 . The sensor windows  44  are each positioned in the wall  34 . The sensor windows  44  may be flat. For example, the sensor windows  44  may have a rectangular shape. The sensor windows  44  are transparent with respect to whatever medium the sensor  20  is capable of detecting. For example, in the example in which the sensor  20  is a lidar sensor, then the sensor windows  44  are transparent with respect to light at the wavelength generated and detectable by the sensor  20 . 
     The sensor housing  14  defines the inlet  16 . The inlet  16  may be, for example, an opening in a vehicle-forward side of the sensor housing  14  to receive air from the exterior of the vehicle  12  as the vehicle  12  is in motion. The inlet  16  may be vehicle-forward of the sensor assembly  18 . Specifically, the inlet  16  may be vehicle-forward of the sensor  20 . The inlet  16  receives air from the exterior of the vehicle  12  into the sensor housing  14  for cooling and cleaning of the sensor  20 . Specifically, the inlet  16  receives air from the exterior of the vehicle  12  as the vehicle  12  is in motion in a forward direction. The inlet  16  may be spaced upwardly from the vehicle roof  28 , i.e., a portion of the sensor housing  14  may be between the vehicle roof  28  and the inlet  16 . The inlet  16  may be spaced downwardly from the sensor assembly  18 , i.e., a portion of the sensor housing  14  may be between the inlet  16  and the sensor assembly  18 . 
     The inlet  16  is in fluid communication with the cavity  24 . In other words, air may pass through the inlet  16  and may be directed into the cavity  24  of the sensor assembly  18 . Specifically, the sensor housing  14  may define a channel  46  extending from the inlet  16  to the cavity  24 . The inlet  16  is in fluid communication with the cavity  24  through the channel  46 . In other words, air from the exterior of the vehicle  12 , as the vehicle  12  is in motion, may be received by the inlet  16  and be directed by the channel  46  into the cavity  24  of the sensor assembly  18 . The air may move within the cavity  24  and around the sensor  20  to cool and clean the sensor  20 . 
     With continued reference to  FIGS.  4 - 6   , the assembly  10  may include secondary blowers  38  supported by the sensor housing  14  in various locations within the sensor housing  14 . The secondary blowers  38  may take air intake from the exterior of the vehicle  12  to provide further air cleaning and cooling to the sensor assembly  18 , i.e., the sensor  20 . In other words, the secondary blowers  38  may be in fluid communication with the cavity  24 . The secondary blowers  38  may move air inside the sensor housing  14  and into the cavity  24  of the sensor assembly  18  in conjunction with the inlet  16 . 
     The assembly  10  may include any number of additional sensors (not number) designed to detect features of the outside world. The additional sensors may be supported by the sensor housing  14  at various locations around the sensor housing  14 . The additional sensor may be a radar sensor, a scanning laser range finder, a light detection and ranging lidar device, or an image processing sensor such as a camera. 
     With reference to the example embodiment shown in  FIG.  4   , the inlet  16  and the channel  46  define an air flowpath  50  from the inlet  16  to the cavity  24 . The air flowpath  50  extends from the inlet  16 , along the channel  46 , and into the cavity  24 . The air from the exterior of the vehicle  12  moves into the inlet  16 , along the channel  46 , and into the cavity  24  to define the air flowpath  50 . At least a portion of the air flowpath  50  extends along the axis A. In other words, a portion of the air flowpath  50  may extend along the axis A into the cavity  24 . The air flowpath  50  may extend generally parallel to the sensor  20  inside the cover  22 . As the air flowpath  50  leaves the channel  46 , the air flowpath  50  moves upwardly from the sensor housing  14  and into the cavity  24 . The air moving along the air flowpath  50  fills the cavity  24  to clean and cool the sensor  20 . In other words, the air moves between the cover  22  and the sensor  20  to clean and cool the sensor  20 . The air flowpath  50  is indicated in  FIG.  4    by arrows extending between the inlet  16  and the cavity  24 . 
     With reference to the example embodiment shown in  FIG.  5   , the assembly  10  may include a blower  30  supported by the sensor housing  14  at the inlet  16 . The blower  30  may supplement the air flowpath  50  into the channel  46  to cool and clean the sensor  20 . For example, when the vehicle  12  is not in motion, less air may pass through the inlet  16  and into the cavity  24 . In such an example, the blower  30  allows for air to be drawn into the channel  46  and cavity  24  through the inlet  16  despite the vehicle  12  being stationary. In other examples, such as when the vehicle  12  is in motion, the blower  30  supplements the air moving into the inlet  16  to provide additional air into the cavity  24  of the sensor assembly  18 . The air flowpath  50  is indicated in  FIG.  5    by arrows extending between the inlet  16  and the cavity  24 . 
     With reference to the example embodiment shown in  FIG.  6   , the assembly  10  includes an outlet  40  in fluid communication with the inlet  16 . The sensor housing  14  may define the outlet  40 . The outlet  40  may be spaced from the sensor assembly  18  in the vehicle-forward direction. The outlet  40  is aimed at the sensor assembly  18 , i.e., the sensor  20 . The outlet  40  may act as an “air curtain” to deflect potential debris, e.g., water, insects, dirt, etc., from reaching the sensor assembly  18  as the vehicle  12  is moving. Air received by the inlet  16  may exit the outlet  40  adjacent the sensor assembly  18  to deflect potential debris. 
     With continued reference to  FIG.  6   , the sensor assembly  18  may define a pair of channels  46 ,  48  in fluid communication with the inlet  16 , the cavity  24 , and/or the outlet  40 . For example, the sensor assembly  18  defines the channel  46  extending from the inlet  16  to the cavity  24  and a second channel  48  extending from the inlet  16  to the outlet  40 . In such an example, the inlet  16  is in fluid communication with the cavity  24  through the channel  46  and the inlet  16  is in fluid communication with the outlet  40  through the second channel  48 . In other words, the inlet  16  is in fluid communication with the cavity  24  and the outlet  40 . 
     With continued reference to  FIG.  6   , the air received by the inlet  16  may be split between the channel  46  and the second channel  48 . For example, a portion of the air may travel along the channel  46  and into the cavity  24  while the remaining air may travel along the second channel  48  and out the outlet  40 . Specifically, the inlet  16  and the channel  46  may define a first air flowpath  52  from the inlet  16  to the cavity  24  and the inlet  16  and the second channel  48  may define a second flowpath from the inlet  16  to the outlet  40 . Regarding the first air flowpath  52 , the inlet  16  receives air from the exterior of the vehicle  12  and the air moves from the inlet  16 , along the channel  46 , and into the cavity  24  of the sensor assembly  18 . Regarding the second air flowpath  54 , the inlet  16  receives air from the exterior of the vehicle  12  and the air moves from the inlet  16 , along the second channel  48 , and out the outlet  40 . The second air flowpath  54  may exit the outlet  40  and extend adjacent the sensor  20 . As discussed above, the second air flowpath  54  may deflect potential debris from reaching the sensor assembly  18  while the vehicle  12  is in motion, i.e., act as an “air curtain.” The first air flowpath  52  and the second air flowpath  54  are indicated in  FIG.  6    by arrows extending between the inlet  16  and the cavity  24  and the inlet  16  and the outlet  40 . 
     With continued reference to  FIG.  6   , the sensor housing  14  defines a wedge  42  extending upwardly adjacent the outlet  40  and vehicle-forward of the sensor  20 . The sensor housing  14  may define a third air flowpath  56  exterior to the sensor housing  14  along the wedge  42  and adjacent the sensor  20 . The air runs along the exterior of the sensor housing  14  when the vehicle  12  is in motion and is directed upwardly by the wedge  42 . Specifically, the wedge  42  directs air, as the vehicle  12  is in motion, upwardly from the sensor housing  14  and vehicle-forward of the sensor assembly  18 . The third air flowpath  56  and the second air flowpath  54  may both act together as an “air curtain” vehicle-forward of the sensor assembly  18  to deflect potential debris from reaching the sensor assembly  18 . The third air flowpath  56  is indicated in  FIG.  6    by arrows extending along the exterior of the sensor housing  14  and upward from the wedge  42 . 
     The adjectives first, second, and third are used throughout this document as identifiers and are not intended to signify importance, order, or quantity. 
     The disclosure has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present disclosure are possible in light of the above teachings, and the disclosure may be practiced otherwise than as specifically described.