Sensor System

Abstract

A sensor (11) detects an object positioned in a detection direction. A deflection device (12) periodically changes the detection direction. A housing (13) houses the sensor (11) and the deflection device (12). A vibration absorption device (14) is disposed between a support (31) and the housing (13). The vibration absorption device (14) includes a first vibration absorber (141), a second vibration absorber (142), and an intermediate member (143). The intermediate member (143) has a first surface (143a) facing the housing (13) across a first gap (G1), and a second surface (143b) facing the support body (31) across a second gap (G2). The first vibration absorber (141) is disposed between the housing (13) and the first surface (143a) of the intermediate member (143). The second vibration absorber (142) is disposed between the support body (31) and the second surface (143b) of the intermediate member (143).

Description

[Technical Field]

[0001] The present disclosure relates to a sensor system mounted on a monitoring device. [Background technology]

[0002] Patent Document 1 discloses a LiDAR (Light Detection and Ranging) system mounted on a vehicle as an example of a sensor system. The LiDAR system includes a deflector that periodically changes the direction of light emitted from a light source to detect objects outside the vehicle. The deflector can be a source of periodic vibrations. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-519891 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a need to suppress malfunctions caused by periodic vibrations generated by sensor systems. [Means for solving the problem]

[0005] A first aspect that can be provided by the present disclosure is a sensor system mounted on a monitoring device, comprising: a sensor for detecting an object located in a detection direction; a deflection device that periodically changes the detection direction; a housing containing the sensor and the deflection device; a vibration absorbing device disposed between a support constituting a part of the monitoring device and the housing; It is equipped with The vibration absorbing device is an intermediate member having a first surface facing the housing across a first gap and a second surface facing the support body across a second gap; a first vibration absorbing device disposed between the first surface of the intermediate member and the housing; a second vibration absorbing device disposed between the second surface of the intermediate member and the support; Contains:

[0006] A second aspect that can be provided by the present disclosure is a sensor system mounted on a monitoring device, comprising: a sensor for detecting an object located in a detection direction; a deflection device that periodically changes the detection direction; a housing containing the sensor and the deflection device; a vibration absorbing device disposed between a support constituting a part of the monitoring device and the housing; It is equipped with The vibration absorber includes a pair of magnetized members that are magnetized to the same polarity and are arranged to face each other across a gap in a first direction.

[0007] A third aspect that can be provided by the present disclosure is a sensor system mounted on a monitoring device, comprising: a sensor for detecting an object located in a detection direction; a deflection device that periodically changes the detection direction; a housing containing the sensor and the deflection device; a vibration absorbing device disposed between a support constituting a part of the monitoring device and the housing; It is equipped with The vibration absorbing device is a pair of members arranged to face each other in a first direction; a cavity that accommodates at least a portion of the pair of members while allowing displacement of the pair of members in the first direction; a control device that controls the amount of fluid contained in the cavity so as to form a gap between the pair of members; It is equipped with:

[0008] As mentioned above, a deflection device that periodically changes the detection direction of a sensor can be a source of periodic vibration. If the housing that houses the sensor and deflection device resonates with the periodic vibration, larger vibrations can occur, causing problems. For example, the resonant vibration itself or the sound associated with the resonant vibration can be transmitted to the monitoring device, causing discomfort to the user. Alternatively, the transmission of the resonant vibration to the sensor can reduce the sensor's detection accuracy.

[0009] According to the configuration of the first aspect, resonant vibrations generated in the housing are absorbed by the first vibration absorber and then transmitted to the intermediate member. The intermediate member is disposed between the housing and the support body across the first and second gaps, allowing for flexible deformation, thereby facilitating absorption of the resonant vibrations. The remaining resonant vibrations are further absorbed by the second vibration absorber, significantly attenuating vibrations that could otherwise be transmitted to the support body. This makes it possible to prevent malfunctions caused by periodic vibrations generated by the sensor system.

[0010] According to the second aspect, when the pair of magnetized members approaches each other due to resonant vibrations generated in the housing, the repulsive force that tries to separate them increases. That is, the gap formed between the pair of magnetized members and the repulsive force acting between the pair of magnetized members function as a cushion, thereby significantly attenuating vibrations that could be transmitted to the support. Therefore, malfunctions caused by periodic vibrations generated by the sensor system can be suppressed.

[0011] According to a configuration of the third aspect, a vibration-absorbing device including a pair of members isolated by a fluid is interposed between a housing and a support. For example, when the pair of members approach each other due to resonant vibrations generated in the housing, the control device increases the amount of fluid contained in the cavity. This acts as a force that tends to widen the gap. Conversely, when the pair of members move away from their initial state, the control device reduces the amount of fluid contained in the cavity. This acts as a force that tends to narrow the gap. In other words, the fluid that forms the gap between the pair of members functions as a vibration-damping material, thereby significantly attenuating vibrations that could be transmitted to the support. This makes it possible to suppress malfunctions caused by periodic vibrations generated by the sensor system. [Brief explanation of the drawings]

[0012] [Figure 1] 1 illustrates an example of the configuration of a sensor system according to an embodiment. [Figure 2] 2 illustrates a specific configuration of the sensor and deflection device in FIG. 1. [Figure 3] 2 illustrates a vehicle equipped with the sensor system of FIG. 1; [Figure 4] 1 shows an external appearance of a vibration absorber according to an example. [Figure 5] 1 shows an external appearance of a vibration absorber according to an example. [Figure 6] 10 shows the appearance of a vibration absorber according to another example. [Figure 7] 10 shows the appearance of a vibration absorber according to another example. [Figure 8] 2 is a diagram for explaining an analysis of a resonant vibration mode for the housing of FIG. 1. FIG. [Figure 9] 1. FIG. 3 shows another example of the shape of the housing of FIG. [Figure 10] 10 illustrates an example of the appearance of the sensor system as viewed in the direction of arrow X in FIG. 9. [Figure 11] 2 shows an example of the appearance of the intermediate member in FIG. 1. [Figure 12] 2 shows another example of the appearance of the intermediate member in FIG. 1. [Figure 13]2 illustrates the positional relationship between the first vibration absorbing device and the second vibration absorbing device in FIG. 1; [Figure 14] 10 illustrates the configuration of a sensor system according to another embodiment. [Figure 15] 10 shows the configuration of a vibration absorber according to another example. [Figure 16] 10 shows the operation of a vibration absorber according to another example. [Figure 17] 10 shows the configuration of a vibration absorber according to another example. [Figure 18] 10 shows the operation of a vibration absorber according to another example. [Figure 19] 10 shows the configuration of a vibration absorber according to another example. [Figure 20] 10 shows the operation of a vibration absorber according to another example. [Figure 21] 10 shows the configuration of a vibration absorber according to another example. [Figure 22] 10 shows the operation of a vibration absorber according to another example. [Figure 23] 15 shows another example of the shape of the housing of FIG. 14. [Figure 24] 24 illustrates an example of the appearance of the sensor system as seen from the direction of arrow XXIV in FIG. 23. [Figure 25] 15 shows another example of the configuration of the sensor system of FIG. 14. [Figure 26] 26 illustrates the positional relationship between the first vibration absorbing device and the second vibration absorbing device in FIG. 25. [Figure 27] 1 illustrates an example of a lighting device in which a sensor system according to each embodiment is mounted. [Figure 28] 1 illustrates an example of a transportation infrastructure facility in which a sensor system according to each embodiment is installed. DETAILED DESCRIPTION OF THE INVENTION

[0013]

[0023] The following description will discuss in detail exemplary embodiments with reference to the accompanying drawings, in which the scale of each element is appropriately changed so that it can be clearly seen.

[0014] In the accompanying drawings, arrow F indicates the forward direction of the illustrated structure. Arrow B indicates the rearward direction of the illustrated structure. Arrow L indicates the leftward direction of the illustrated structure. Arrow R indicates the rightward direction of the illustrated structure. In the following description, "left" and "right" indicate the left and right directions as seen from the driver's seat.

[0015] 1 illustrates the configuration of a sensor system 10 according to one embodiment. The sensor system 10 includes a sensor 11 and a deflection device 12.

[0016] 2, the sensor 11 includes a light-emitting element 111. The light-emitting element 111 is configured to emit detection light SL in the detection direction. A semiconductor light-emitting element such as a light-emitting diode, a laser diode, or an EL element can be used as the light-emitting element 111. For example, infrared light with a wavelength of 905 nm can be used as the detection light SL.

[0017] The sensor 11 includes a light receiving element 112. The light receiving element 112 is configured to detect return light RL generated by an object 20 located in the detection direction. The light receiving element 112 may be a semiconductor light receiving element such as a photodiode, phototransistor, or photoresistor that is sensitive to the wavelength of the detection light SL. In other words, the sensor 11 is configured to detect an object 20 located in the detection direction.

[0018] The deflection device 12 includes a first lens 121, a second lens 122, and a support frame 123. The configuration and arrangement of the first lens 121 are determined so as to allow the detection light SL emitted from the light-emitting element 111 to pass through. The configuration and arrangement of the second lens 122 are determined so as to allow the return light RL to pass through toward the light-receiving element 112. The support frame 123 supports the first lens 121 and the second lens 122.

[0019] The deflection device 12 includes an actuator 124. The actuator 124 is configured to periodically displace the support frame 123 in a direction intersecting the detection direction. This displacement periodically changes the traveling direction of the detection light SL, i.e., the detection direction of the sensor 11. In Figure 2, the first lens 121, second lens 122, detection light SL, and return light RL after displacement are illustrated by two-dot chain lines.

[0020] The sensor 11 can acquire distance information to the object 20 located in the detection direction, for example, based on the time from when the detection light SL is emitted in the detection direction to when the return light RL is detected. Information related to the shape of the object 20 can be acquired by acquiring distance information for multiple points while changing the detection direction using the deflection device 12. Additionally or alternatively, information related to attributes such as the material of the object 20 can be acquired based on the difference in waveform between the detection light SL and the return light RL.

[0021] The sensor system 10 is mounted on a vehicle 30 shown in FIG. 3. The shape of the body of the vehicle 30 is merely an example. For example, the sensor system 10 is disposed on the left front part LF of the vehicle 30. The left front part LF is an area located to the left of the center in the left-right direction of the vehicle 30 and in front of the center in the front-rear direction of the vehicle 30. In this case, the detection direction of the sensor 11 is determined to include at least one of the front and left of the left front part LF. The vehicle 30 is an example of a moving body. The vehicle 30 is an example of a monitoring device.

[0022] 1, the sensor system 10 includes a housing 13. The housing 13 houses a sensor 11 and a deflection device 12. The material forming the housing 13 can be determined appropriately.

[0023] The sensor system 10 includes a vibration absorber 14. The vibration absorber 14 is configured to be disposed between the housing 13 and the support body 31 when the sensor system 10 is mounted on the vehicle 30. The support body 31 is a component that constitutes a part of the vehicle 30.

[0024] The vibration absorber 14 includes a first vibration absorber 141, a second vibration absorber 142, and an intermediate member 143. The intermediate member 143 has a first surface 143a and a second surface 143b. The first surface 143a faces the housing 13 across a first gap G1. The second surface 143b faces the support body 31 across a second gap G2.

[0025] The first vibration absorbing device 141 is disposed between the first surface 143a of the intermediate member 143 and the housing 13. The second vibration absorbing device 142 is disposed between the second surface 143b of the intermediate member 143 and the support body 31.

[0026] The first vibration absorbing device 141 and the second vibration absorbing device 142 may each have the configurations exemplified in Figures 4 and 5. When describing the configuration common to the first vibration absorbing device 141 and the second vibration absorbing device 142, the first vibration absorbing device 141 and the second vibration absorbing device 142 will be collectively referred to as the "vibration absorbing device 140" as necessary.

[0027] Fig. 4 illustrates an example of the external appearance of the vibration absorber 140 as viewed from the side of the housing 13. Fig. 5 illustrates an example of the external appearance of the vibration absorber 140 as viewed from the side of the support body 31.

[0028] The vibration absorber 140 includes a rigid portion 140a and an elastic portion 140b. The rigid portion 140a has higher rigidity than the elastic portion 140b. The rigid portion 140a may be made of a metal alloy. Examples of metal alloys include brass and stainless steel. The elastic portion 140b has higher elasticity than the rigid portion 140a. The elastic portion 140b may be made of a vibration absorbing material such as Sorbothane (registered trademark) or Hanenite (registered trademark), cork, rubber, or the like.

[0029] The vibration absorber 140 is disposed so that the elastic portion 140 b is in contact with any one of the housing 13 , the intermediate member 143 , and the support body 31 .

[0030] As illustrated in FIG. 6, the vibration absorber 140 may be configured to include a supporting member 140c and a supported member 140d. The supporting member 140c has a conical protrusion 140e. The supported member 140d has a recess 140f. For example, the supporting member 140c is attached to the first surface 143a of the intermediate member 143 and the support body 31, and the supported member 140d is attached to the housing 13 and the second surface 143b of the intermediate member. When the protrusion 140e and the recess 140f are coupled together as illustrated in FIG. 7, the supported member 140d is supported by the tip of the protrusion 140e.

[0031] As mentioned above, a deflection device that periodically changes the detection direction of a sensor can be a source of periodic vibration. If the housing that houses the sensor and deflection device resonates with the periodic vibration, larger vibrations can occur, causing problems. For example, the resonant vibration itself or the sound associated with the resonant vibration can be transmitted to the vehicle, causing discomfort to passengers. Alternatively, the transmission of the resonant vibration to the sensor can reduce the sensor's detection accuracy.

[0032] In the configuration of the sensor system 10 according to this embodiment, an intermediate member 143 sandwiched between a first vibration absorbing device 141 and a second vibration absorbing device 142 is interposed between the housing 13 and the support body 31. Resonant vibrations generated in the housing 13 are absorbed by the first vibration absorbing device 141 and transmitted to the intermediate member 143. The intermediate member 143 is disposed between the housing 13 and the support body 31 across the first gap G1 and the second gap G2, allowing for flexural deformation, which promotes absorption of the resonant vibrations. The remaining resonant vibrations are further absorbed by the second vibration absorbing device 142, which significantly attenuates vibrations that could be transmitted to the support body 31. This makes it possible to suppress malfunctions caused by periodic vibrations generated by the sensor system 10.

[0033] The first vibration absorber 141 can be disposed at a position corresponding to an antinode of a vibration mode of a resonant frequency included in vibrations generated in the housing 13 due to the operation of the deflection device 12. The position of the antinode of the vibration mode can be identified by an analytical method used in well-known active vibration control methods.

[0034] 8 shows some examples of vibration modes that can be identified as a result of vibration mode analysis performed on the bottom surface 131 of the housing 13. Vibration mode M1 includes odd-order vibration modes in the X direction and odd-order vibration modes in the Y direction. Vibration mode M2 ​​includes odd-order vibration modes in the X direction and even-order vibration modes in the Y direction. Vibration mode M3 includes even-order vibration modes in the X direction and odd-order vibration modes in the Y direction. Vibration mode M4 includes even-order vibration modes in the X direction and even-order vibration modes in the Y direction.

[0035] The position of the antinode of the vibration mode thus specified in advance corresponds to the position where the driving force of the resonant vibration that may occur in the housing 13 due to the operation of the deflection device 12 becomes large. By disposing the first vibration-absorbing device 141 at this position, the resonant vibration that occurs in the housing 13 can be efficiently damped.

[0036] For example, it can be seen that the positions of the four first vibration absorbers 141 illustrated in FIG. 8 correspond to the positions of the four antinodes in the vibration mode M4.

[0037] In particular, odd-order vibration modes have a high acoustic radiation efficiency, so by placing the first vibration absorbing device 141 at the antinode position of the odd-order vibration mode, the generation of sound waves associated with resonant vibration is suppressed, and the vibration noise that can be transmitted to the occupants of the vehicle 30 can be reduced.

[0038] As an example, if vibration mode M1 is identified for the bottom surface 131 of the housing 13, a first vibration absorbing device 141a may be arranged at a position corresponding to the antinode of the vibration mode M1 in addition to or instead of the above-described first vibration absorbing device 141. As another example, if vibration mode M2 ​​is identified for the bottom surface 131 of the housing 13, a first vibration absorbing device 141b may be arranged at a position corresponding to the antinode of the vibration mode M1 in addition to or instead of the above-described first vibration absorbing device 141.

[0039] In addition, the position of the first vibration absorbing device 141 does not need to strictly coincide with the position of the antinode of the vibration mode, as long as it avoids a position corresponding to a node of the vibration mode of the resonant frequency contained in the vibration generated in the housing 13 due to the operation of the deflection device 12.

[0040] The shape of the housing 13 does not need to be a rectangular parallelepiped having a flat bottom surface 131. As illustrated in Figures 9 and 10, the housing 13 may have a cylindrical shape having a curved surface 132 facing the intermediate member 143. In this case, the above-mentioned vibration mode analysis is performed on the curved surface 132, and the first vibration absorber 141 is positioned so as to avoid the node positions of the identified resonant vibration mode.

[0041] As shown in Fig. 11, the intermediate member 143 of the vibration absorber 14 can be formed to have a plurality of openings 143c. Each opening 143c connects the first surface 143a to the second surface 143b. That is, each opening 143c connects the first gap G1 to the second gap G2. Fig. 12 shows another example of the shape of the openings 143c.

[0042] With this configuration, even if the intermediate member 143 vibrates due to the resonant vibration from the housing 13 transmitted through the first vibration absorber 141, it is possible to significantly reduce the efficiency with which air is pushed out toward the support body 31 due to the vibration. This suppresses the generation of sound waves associated with the resonant vibration, thereby reducing the vibration noise that may be transmitted to the occupants of the vehicle 30.

[0043] The number and shape of the openings 143c can be determined appropriately within a range that satisfies the requirements of having sufficient rigidity to support the housing 13 via the first vibration absorbing device 141 and having an opening ratio that is sufficient to exert the above-mentioned sound wave suppression effect.

[0044] As illustrated in FIG. 13, the second vibration absorbing device 142 can be disposed so that it does not overlap at least a portion with the first vibration absorbing device 141 when viewed in the normal direction of the first surface 143 a of the intermediate member 143 .

[0045] Since the vibration mode occurring in the intermediate member 143 is different from the vibration mode occurring in the housing 13, by arranging the second vibration absorbing device 142 at a position different from the first vibration absorbing device 141 when viewed from the normal direction of the first surface 143a of the intermediate member 143, vibrations that may be transmitted to the support body 31 can be efficiently absorbed.

[0046] The vibration mode analysis described with reference to FIG. 8 may be performed on the intermediate member 143, and the second vibration absorber 142 may be arranged to avoid nodes of the identified vibration mode.

[0047] Fig. 14 illustrates the configuration of a sensor system 10 according to another embodiment. Elements having substantially the same configuration as those in the embodiment described with reference to Fig. 1 are given the same reference numerals, and repeated description will be omitted.

[0048] In this embodiment, the vibration absorber 14 is mounted on the support body 31, and the housing 13 is mounted on the vibration absorber 14. In the following description, the up-down direction in Fig. 14 will be referred to as the "mounting direction" as necessary. The mounting direction is an example of the first direction.

[0049] As illustrated in FIG. 15 , the vibration absorber 14 includes a first magnetized member 14a and a second magnetized member 14b. The first magnetized member 14a and the second magnetized member 14b are magnetized to the same polarity. The first magnetized member 14a and the second magnetized member 14b are arranged to face each other in the loading direction across a gap G due to a repulsive force RP generated by the same polarity magnetization. In other words, the first magnetized member 14a and the second magnetized member 14b maintain a non-contact state at a position where their own weights and the repulsive force RP are balanced. The first magnetized member 14a and the second magnetized member 14b are an example of a pair of magnetized members.

[0050] The first magnetized member 14a is configured to be coupled to the housing 13. The second magnetized member 14b is configured to be coupled to the support 31. The expression "coupled" as used in this specification means a state in which two members are fixed by adhesion or welding, a state in which two members are fixed by screwing, fitting, engaging, or the like, or a state in which two members are in contact with each other by being placed on top of each other. In other words, the housing 13 and the support 31 are connected by the vibration absorber 14 with a gap G formed therein.

[0051] As mentioned above, a deflection device that periodically changes the detection direction of a sensor can be a source of periodic vibration. If the housing that houses the sensor and deflection device resonates with the periodic vibration, larger vibrations can occur, causing problems. For example, the resonant vibration itself or the sound associated with the resonant vibration can be transmitted to the vehicle, causing discomfort to passengers. Alternatively, the transmission of the resonant vibration to the sensor can reduce the sensor's detection accuracy.

[0052] In the configuration of sensor system 10 according to this embodiment, a vibration absorber 14 including a pair of magnetized members magnetized to the same polarity is interposed between housing 13 and support body 31. As illustrated in FIG. 16 , when the pair of magnetized members approach each other due to resonant vibrations generated in housing 13, a repulsive force RP that tries to separate the two magnetized members becomes stronger. That is, the gap G formed between the pair of magnetized members and the repulsive force RP acting between the pair of magnetized members function as a cushion, thereby significantly attenuating vibrations that could be transmitted to support body 31. This makes it possible to suppress malfunctions caused by periodic vibrations generated by sensor system 10.

[0053] 15 and 16, the vibration absorber 14 may include a regulating member 14c. The regulating member 14c has a surface extending in a direction intersecting the loading direction and regulates the displacement of the first magnetized member 14a and the second magnetized member 14b in the loading direction. The direction intersecting the loading direction is an example of the second direction.

[0054] With this configuration, the width of the gap G is maintained within an appropriate range, making it easy to maintain the opposing state of the first magnetized member 14a and the second magnetized member 14b. For example, it is possible to prevent a situation in which the first magnetized member 14a and the second magnetized member 14b are separated to such an extent that they cannot return to an equilibrium state due to a large repulsive force RP that may be generated when the first magnetized member 14a and the second magnetized member 14b come too close to each other due to an unexpected impact that exceeds the resonant vibration.

[0055] In addition to or instead of the restricting member 14c, the vibration absorber 14 may include a guide member 14d. The guide member 14d has a surface extending along the loading direction, and allows the first magnetized member 14a and the second magnetized member 14b to be displaced in the loading direction while restricting their displacement in a direction intersecting the loading direction.

[0056] The repulsive force RP acting between the first magnetized member 14a and the second magnetized member 14b may have a component in a direction intersecting the loading direction. By providing the guide member 14d as described above, it is possible to prevent the first magnetized member 14a and the second magnetized member 14b from being unable to maintain the opposing state in the loading direction due to the repulsive force RP acting in a direction intersecting the loading direction.

[0057] 17 shows another example of the configuration of the vibration absorber 14. In this example, a restricting member 14e is disposed between the first magnetized member 14a and the second magnetized member 14b. The restricting member 14e is coupled to each of the first magnetized member 14a and the second magnetized member 14b. The restricting member 14e can be made of a vibration-absorbing material such as Sorbothane (registered trademark) or Hanenite (registered trademark), or an elastic material such as rubber.

[0058] The restricting member 14e restricts displacement of the first magnetized member 14a and the second magnetized member 14b in the stacking direction. Specifically, when the first magnetized member 14a and the second magnetized member 14b approach each other due to vibrations generated by the housing 13, the restricting member 14e elastically compresses and deforms, thereby absorbing the vibrations and suppressing excessive approach, i.e., the generation of excessive repulsive force RP. Even if an excessive repulsive force RP is generated by an unexpected impact that exceeds the resonant vibration, as illustrated in FIG. 18 , the restricting member 14e prevents the first magnetized member 14a and the second magnetized member 14b from separating excessively, thereby preventing the first magnetized member 14a and the second magnetized member 14b from separating to an extent that they cannot return to an equilibrium state.

[0059] Therefore, the width of the gap G can be kept within an appropriate range with a simpler configuration, and the opposing state of the first magnetized member 14a and the second magnetized member 14b can be maintained.

[0060] In addition to the restricting member 14e, the guide member 14d described with reference to FIGS. 15 and 16 may be provided.

[0061] 8, the vibration absorber 14 can be disposed at a position corresponding to an antinode of a vibration mode of a resonant frequency included in vibrations generated in the housing 13 due to the operation of the deflection device 12. The position of the antinode of the vibration mode can be identified by an analytical method used in well-known active vibration control methods.

[0062] In particular, odd-order vibration modes have a high acoustic radiation efficiency, so by placing the vibration absorber 14 at the antinode position of the odd-order vibration mode, the generation of sound waves associated with resonant vibration is suppressed, and the vibration noise that can be transmitted to the occupants of the vehicle 30 can be reduced.

[0063] In addition, the position of the vibration absorber 14 does not need to strictly coincide with the position of the antinode of the vibration mode, as long as it avoids a position corresponding to a node of the vibration mode of the resonant frequency contained in the vibration generated in the housing 13 due to the operation of the deflection device 12.

[0064] Figure 19 shows another example of the configuration of the vibration absorber 14. Elements having substantially the same configuration as those in the examples described with reference to Figures 15 to 18 are given the same reference numerals, and repeated explanations will be omitted. The vibration absorber 14 of this example includes a housing that defines a cavity 14f. The cavity 14f accommodates a portion of the first member 14g and the second member 14h while allowing displacement of the first member 14g and the second member 14h in the loading direction.

[0065] The vibration absorber 14 according to this embodiment includes a control device 14i. The control device 14i is configured to be able to control the amount of fluid contained in the cavity 14f. Examples of the fluid include compressed air and oil. The control device 14i can be realized, for example, by a pump device. The fluid contained in the cavity 14f forms a gap G between the first member 14g and the second member 14h. In other words, the housing 13 and the support 31 are connected by the vibration absorber 14 with the gap G formed therein.

[0066] For example, the vibration absorber 14 may include a displacement sensor that detects the displacement of each of the first member 14g and the second member 14h. The displacement sensor may be realized by an optical sensor installed on the inner wall of the cavity 14f, an acceleration sensor installed on each of the first member 14g and the second member 14h, or the like. The displacement sensor may be configured to output a detection signal corresponding to the amount of displacement of each of the first member 14g and the second member 14h. The control device 14i may be configured to change the amount of fluid contained in the cavity 14f when the amount of displacement corresponding to the detection signal exceeds a threshold.

[0067] As mentioned above, a deflection device that periodically changes the detection direction of a sensor can be a source of periodic vibration. If the housing that houses the sensor and deflection device resonates with the periodic vibration, larger vibrations can occur, causing problems. For example, the resonant vibration itself or the sound associated with the resonant vibration can be transmitted to the vehicle, causing discomfort to passengers. Alternatively, the transmission of the resonant vibration to the sensor can reduce the sensor's detection accuracy.

[0068] In the configuration of the sensor system 10 according to this embodiment, a vibration absorber 14 including a pair of members separated by a fluid is interposed between the housing 13 and the support 31. As illustrated in FIG. 20 , when the pair of members approach each other due to resonant vibrations generated in the housing 13, the control device 14i increases the amount of fluid contained in the cavity 14f. This acts as a force that widens the gap G. Conversely, when the pair of members move away from their initial state, the control device 14i decreases the amount of fluid contained in the cavity 14f. This acts as a force that narrows the gap G. In other words, the fluid that forms the gap G between the pair of members functions as a vibration-damping material, significantly attenuating vibrations that could be transmitted to the support 31. This makes it possible to suppress malfunctions caused by periodic vibrations generated by the sensor system 10.

[0069] The first member 14g and the second member 14h can be magnetized to the same polarity. In this case, as illustrated in Fig. 21, the first member 14g and the second member 14h face each other in the loading direction across a gap G due to a repulsive force RP generated by the magnetization to the same polarity. In other words, the first member 14g and the second member 14h maintain a non-contact state at a position where their own weights in the fluid and the repulsive force RP are balanced.

[0070] With this configuration, when the pair of members approach each other due to resonant vibrations generated in the housing 13, as illustrated in Fig. 22, the repulsive force RP that tries to separate the members becomes stronger. That is, the gap G formed between the pair of members and the repulsive force RP acting between the pair of members function as a cushion, thereby damping vibrations that may be transmitted to the support body 31. Therefore, even with a simple configuration, it is possible to obtain vibration absorption performance that is equal to or better than that of the configuration described with reference to Figs. 19 and 20, even if the amount of fluid control by the control device 14i is reduced.

[0071] In this example, as described with reference to FIGS. 17 and 18, the restricting member 14e may be disposed between the first member 14g and the second member 14h.

[0072] The shape of the housing 13 illustrated in Fig. 14 does not need to be a rectangular parallelepiped shape having a flat bottom surface 131. As illustrated in Figs. 23 and 24, the housing 13 may have a cylindrical shape having a curved surface 132 facing the support 31. In this case, the above-described vibration mode analysis is performed on the curved surface 132, and the vibration absorber 14 is positioned so as to avoid the node positions of the identified resonant vibration mode.

[0073] 19, the sensor system 10 may include a first detection device 15. The first detection device 15 is configured to output a first detection signal DS1 corresponding to a physical quantity related to a change occurring in the housing 13 in accordance with the operation of the deflection device 12. Examples of the physical quantity include force, torque, position, rotation angle, velocity, rotation angular velocity, mass, moment of inertia, viscous damping coefficient, viscous friction coefficient, spring constant, etc.

[0074] The first detection device 15 may be configured to include a displacement sensor attached to the housing 13. Examples of the displacement sensor include a strain gauge, an acceleration sensor, and an optical fiber sensor. The optical fiber sensor may employ a system that detects reflected light from an FBG (Fiber Bragg Grating) formed in an optical fiber, or a system that detects Rayleigh scattered light or Brillouin scattered light generated by glass particles forming the optical fiber. The configurations of the optical fiber sensors according to each system are well known, and therefore detailed explanations thereof will be omitted.

[0075] The relationship between the change occurring in the housing 13 corresponding to the first detection signal DS1 and the resulting displacement of at least one of the first member 14g and the second member 14h is determined in advance through experiments and simulations. The first detection signal DS1 output from the first detection device 15 is input to the control device 14i. The control device 14i is configured to feedback-control the amount of fluid contained in the cavity 14f based on the previously determined relationship and the input first detection signal DS1. That is, the amount of fluid contained in the cavity 14f is increased or decreased so as to suppress the displacement of at least one of the first member 14g and the second member 14h determined through the relationship by the first detection signal DS1.

[0076] The number and positions of the first detection devices 15 attached to the housing 13 to realize the above feedback control can be determined appropriately depending on the physical quantity to be detected. For example, the vibration mode analysis described with reference to Fig. 8 is performed on a specific surface of the housing 13, and the first detection devices 15 can be placed at the antinode positions of the resonant vibration mode identified as a result. At these positions, the changes occurring in the housing 13 due to the operation of the deflection device 12 become large, making it easier to obtain the first detection signal DS1 used for feedback control.

[0077] In addition, the position of the first detection device 15 does not need to strictly coincide with the position of the antinode of the vibration mode, as long as it avoids a position corresponding to a node of the vibration mode of the resonant frequency contained in the vibration generated in the housing 13 due to the operation of the deflection device 12.

[0078] In addition to or instead of the first detection device 15, as illustrated in FIG. 19 , the sensor system 10 may include a second detection device 16. The second detection device 16 is configured to detect the state of the vehicle 30 based on information acquired from a plurality of sensors arranged at various locations on the vehicle 30. Examples of the state of the vehicle 30 include the driving state and the surrounding environmental state. Examples of the driving state include speed, whether steering is performed, whether braking is performed, etc. Examples of the surrounding environmental state include the road surface state (whether paved or not, flatness, hardness, etc.), road type (street, highway, mountain road, etc.), weather, time of day, etc. For example, the second detection device 16 may be realized as a function of a control device such as an ECU mounted on the vehicle 30.

[0079] The second detection device 16 is configured to output a second detection signal DS2 corresponding to the detected state of the vehicle 30. Different second detection signals DS2 are determined in advance based on a plurality of expected states of the vehicle 30, and a feedforward control model to be applied to each second detection signal DS2 is determined in advance. The second detection signal DS2 output from the second detection device 16 is input to the control device 14i. The control device 14i is configured to feedforward control the amount of fluid contained in the cavity 14f based on the control model associated with the input second detection signal DS2.

[0080] For example, consider a case where a first state is detected in which the vehicle 30 is traveling on a highway, and a case where a second state is detected in which the vehicle 30 is traveling on an unpaved mountain road. Between the first state and the second state, the latter is more likely to cause unexpected resonant vibration in the housing 13. Therefore, when a second detection signal DS2 corresponding to the second state is input, the control device 14i increases the initial amount of fluid accommodated in the cavity 14f to further enhance the vibration absorption effect.

[0081] With this configuration, not only the resonant vibration of the housing 13 caused by the operation of the deflection device 12 but also the transmission of unexpected resonant vibration of the housing 13 caused by the state of the vehicle 30 to the support body 31 can be suppressed.

[0082] The second detection device 16 may also be configured to accept a control model switching command from the occupant. For example, when driving on an unpaved mountain road, the occupant may input a command to enable feedforward control in the second state using a switch or the like. In this case, the second detection device 16 outputs a second detection signal DS2 corresponding to the command, and the control device 14i increases the initial amount of fluid contained in the cavity 14f to further enhance the vibration absorption effect.

[0083] The above-described feedback control and feedforward control may be used in combination. For example, if deviation from normal detection operation of the sensor 11 is confirmed as a result of enabling feedforward control using the control model corresponding to the second state, it is possible that the cause is that the vibration absorption effect of the control model is too high, causing low-frequency vibrations in the sensor 11. In this case, the control device 14i may automatically change the control model to one that reduces the initial amount of fluid contained in the cavity 14f. This change may also be made in response to a command from the occupant.

[0084] Each function of the control device 14i described above may be realized by a general-purpose microprocessor operating in cooperation with general-purpose memory. Examples of the general-purpose microprocessor include a CPU, an MPU, and a GPU. Examples of the general-purpose memory include a ROM and a RAM. In this case, a computer program for executing the above-described processes may be stored in the ROM. The ROM is an example of a non-transitory computer-readable medium for storing a computer program. The general-purpose microprocessor specifies at least a portion of the computer program stored in the ROM, expands it on the RAM, and executes the above-described processes in cooperation with the RAM. The computer program may be pre-installed in the general-purpose memory, or may be downloaded from an external server device (not shown) via a wireless communication network (not shown) and then installed in the general-purpose memory. In this case, the external server device is an example of a non-transitory computer-readable medium for storing a computer program.

[0085] The functions of the control device 14i may be implemented by a dedicated integrated circuit capable of executing the computer program. Examples of the dedicated integrated circuit include a microcontroller, an ASIC, and an FPGA. In this case, the computer program is pre-installed in a memory element included in the dedicated integrated circuit. The memory element is an example of a non-transitory computer-readable medium storing a computer program. The control device 14i may also be implemented by a combination of a general-purpose microprocessor and a dedicated integrated circuit.

[0086] If the sensor system 10 includes multiple vibration absorbers 14, a single control device 14i may be shared by the multiple vibration absorbers 14.

[0087] 25, the vibration absorber 14 may include a first vibration absorber 141, a second vibration absorber 142, and an intermediate member 143. The intermediate member 143 has a first surface 143a and a second surface 143b. The first surface 143a faces the housing 13 across a first gap G1. The second surface 143b faces the support body 31 across a second gap G2.

[0088] The first vibration absorbing device 141 is disposed between the first surface 143a of the intermediate member 143 and the housing 13. The second vibration absorbing device 142 is disposed between the second surface 143b of the intermediate member 143 and the support body 31.

[0089] Each of the first vibration absorbing device 141 and the second vibration absorbing device 142 may have the configuration described with reference to Figures 15 to 22. That is, in the first vibration absorbing device 141, the first member 14g is connected to the housing 13, and the second member 14h is connected to the intermediate member 143. Similarly, in the second vibration absorbing device 142, the first member 14g is connected to the intermediate member 143, and the second member 14h is connected to the support body 31.

[0090] As long as at least the first vibration absorbing device 141 has this configuration, the second vibration absorbing device 142 can be replaced with a known vibration absorbing material or insulator.

[0091] According to the above-described configuration, resonant vibrations generated in the housing 13 are absorbed by the first vibration-absorbing device 141 and then transmitted to the intermediate member 143. The intermediate member 143 is disposed between the housing 13 and the support 31 across the first gap G1 and the second gap G2, and is therefore permitted to flex and deform, thereby facilitating the absorption of resonant vibrations. The remaining resonant vibrations are further absorbed by the second vibration-absorbing device 142, and therefore vibrations that may be transmitted to the support 31 can be significantly attenuated. This further reduces the occurrence of problems due to periodic vibrations generated by the sensor system 10.

[0092] In this case, the first vibration absorber 141 may be positioned to avoid the nodes of the vibration modes identified by the vibration mode analysis described with reference to FIG.

[0093] As illustrated in FIG. 26, the second vibration absorbing device 142 can be disposed so that it does not overlap at least a portion with the first vibration absorbing device 141 when viewed from the normal direction of the first surface 143a of the intermediate member 143.

[0094] Since the vibration mode occurring in the intermediate member 143 is different from the vibration mode occurring in the housing 13, by arranging the second vibration absorbing device 142 at a position different from the first vibration absorbing device 141 when viewed from the normal direction of the first surface 143a of the intermediate member 143, vibrations that may be transmitted to the support body 31 can be efficiently absorbed.

[0095] The vibration mode analysis described with reference to FIG. 8 may be performed on the intermediate member 143, and the second vibration absorber 142 may be arranged to avoid nodes of the identified vibration mode.

[0096] The above-described embodiments are merely examples for facilitating understanding of the present disclosure. The configurations according to the above-described embodiments may be appropriately modified without departing from the spirit of the present disclosure.

[0097] 1 and 25, there is one intermediate member 143 disposed between the housing 13 and the support body 31. However, at least one more intermediate member may be disposed between the intermediate member 143 and the support body 31. In this case, the vibration absorber 14 is disposed between the intermediate members.

[0098] In addition to or instead of the deflection device 12 having a plurality of lenses illustrated in Fig. 2, the detection direction of the sensor 11 may be periodically changed by an optical reflector. Examples of optical reflectors capable of such an operation include devices using a BladeScan (registered trademark) system, a polygon mirror system, and a MEMS mirror system.

[0099] The sensor system 10 may be mounted on an illumination device 32 illustrated in FIG. 27 in order to emit the detection light SL toward at least one of the front and left sides of the left front part LF of the vehicle 30 as illustrated in FIG.

[0100] The lighting device 32 includes a light source 321. The light source 321 is configured to emit visible light VL. The lighting device 32 includes a housing 322 and a light-transmitting cover 323. The housing 322 and the light-transmitting cover 323 define a lamp chamber 324. The light source 321 and the sensor system 10 are housed in the lamp chamber 324. In this case, a part of the housing 322 can serve as the support body 31.

[0101] In this example, the transmission of vibrations that occur with the operation of the deflection device 12, which periodically changes the detection direction of the sensor 11, is suppressed, so that abnormal noises caused by the transmission of vibrations to the lighting device 32 and fluctuations in lighting due to visible light VL can be suppressed.

[0102] The lighting device 32 may also be mounted on the right front RF of the vehicle 30 illustrated in Fig. 3. The right front RF is an area located to the right of the center in the left-right direction of the vehicle 30 and forward of the center in the front-rear direction of the vehicle 30. The lighting device 32 mounted on the right front RF may have a configuration symmetrical to the lighting device 32 illustrated in Fig. 27. In this case, the detection direction of the sensor 11 includes at least one of the front and right of the right front RF.

[0103] The lighting device 32 may also be mounted on the left rear LB and right rear RB of the vehicle 30 illustrated in FIG. 3 . The left rear LB is an area located to the left of the center in the left-right direction of the vehicle 30 and rear of the center in the front-rear direction of the vehicle 30. The right rear RB is an area located to the right of the center in the left-right direction of the vehicle 30 and rear of the center in the front-rear direction of the vehicle 30. The lighting device 32 mounted on the left rear LB may have a configuration symmetrical in the front-rear direction with the lighting device 32 illustrated in FIG. 27 . In this case, the detection direction of the sensor 11 includes at least one of rear and left of the left rear LB. The lighting device 32 mounted on the right rear RB may have a configuration symmetrical in the left-right direction with the lighting device 32 mounted on the left rear LB. In this case, the detection direction of the sensor 11 includes at least one of rear and right of the right rear RB.

[0104] The moving body on which the lighting device 32 is mounted is not limited to the vehicle 30. Other examples of moving bodies include trains, flying bodies, aircraft, ships, etc. The moving body on which the lighting device 32 is mounted does not need to be driven.

[0105] The lighting device 32 does not need to be mounted on a mobile object. As illustrated in Fig. 28, the lighting device 32 may also be mounted on transportation infrastructure equipment such as a street light 40 or a traffic signal 50. The street light 40 and the traffic signal 50 are examples of monitoring devices.

[0106] When the lighting device 32 is mounted on a street light 40, the area A1 is illuminated by visible light VL emitted from the light source 321, and a pedestrian 60, a vehicle, or the like located within the area A1 can be detected by detection light SL emitted from the sensor system 10. For example, when the sensor system 10 detects that a pedestrian 60 or a vehicle is about to enter an intersection, the information can be communicated via communication to a vehicle 30 that is about to enter the intersection from another direction.

[0107] When the lighting device 32 is mounted on a traffic signal 50, the light source 321 may be used to draw information in an area A2 on the traffic road surface. The detection light SL emitted from the sensor system 10 may be used to detect a pedestrian 60, a vehicle, or the like located within the area A1. For example, when the sensor system 10 detects that a pedestrian 60 or a vehicle is about to enter an intersection, information (such as text, a sign, or a flashing warning color) may be drawn in the area A2 to warn a vehicle 30 about to enter the intersection from another direction.

[0108] The lighting device 32 may also be mounted on a monitoring device installed in a house, a facility, etc. For example, the monitoring device may be configured to turn on the light source 321 to illuminate a predetermined area when an object that has entered the area is detected by the detection light SL emitted from the sensor system 10.

[0109] When the sensor system 10 is mounted on a monitoring device other than a mobile object, it does not necessarily have to be housed in the lamp chamber 324 of the lighting device 32. The sensor system 10 can be placed in an appropriate location according to the specifications of the monitoring device.

[0110] The contents of Japanese Patent Application No. 2021-045479 filed on March 19, 2021, Japanese Patent Application No. 2021-045480 filed on March 19, 2021, and Japanese Patent Application No. 2021-045481 filed on March 19, 2021 are incorporated by reference as part of this disclosure.

Claims

1. A sensor system mounted on a monitoring device, a sensor for detecting an object located in a detection direction; a deflection device that periodically changes the detection direction; a housing containing the sensor and the deflection device; a vibration absorbing device disposed between a support constituting a part of the monitoring device and the housing; It is equipped with The vibration absorbing device is an intermediate member having a first surface facing the housing across a first gap and a second surface facing the support body across a second gap; a first vibration absorbing device disposed between the first surface of the intermediate member and the housing; a second vibration absorbing device disposed between the second surface of the intermediate member and the support; Contains, Sensor system.

2. the first vibration absorbing device is disposed at a position that avoids a node of a vibration mode of a resonant frequency included in vibrations generated in the housing due to operation of the deflection device. The sensor system of claim 1 .

3. The vibration modes include odd-order vibration modes. The sensor system of claim 2 .

4. The intermediate member has an opening that communicates the first gap with the second gap. The sensor system according to any one of claims 1 to 3.

5. the second vibration absorbing device is disposed so as not to overlap at least a portion of the first vibration absorbing device when viewed from a normal direction of the first surface of the intermediate member. The sensor system according to any one of claims 1 to 4.

6. The monitoring device is a mobile object. The sensor system according to any one of claims 1 to 5.

7. The monitoring device includes a light chamber that houses a light source that emits visible light, The housing and the vibration absorbing device are configured to be housed in the lamp chamber. The sensor system according to any one of claims 1 to 6.

8. A sensor system mounted on a monitoring device, a sensor for detecting an object located in a detection direction; a deflection device that periodically changes the detection direction; a housing containing the sensor and the deflection device; a vibration absorbing device disposed between a support constituting a part of the monitoring device and the housing; It is equipped with The vibration absorbing device includes a pair of magnetized members that are magnetized to the same polarity and are arranged to face each other in a first direction with a gap therebetween. Sensor system.

9. the vibration absorbing device includes a restricting member that restricts displacement of the pair of magnetized members in the first direction. The sensor system of claim 8 .

10. The regulating member is disposed between the pair of magnetized members. The sensor system of claim 9.

11. the vibration absorbing device includes a guide member that allows displacement of the pair of magnetized members in the first direction while restricting displacement of the pair of magnetized members in a second direction intersecting the first direction. The sensor system according to any one of claims 8 to 10.

12. the vibration absorber is disposed at a position that avoids a node of a vibration mode of a resonant frequency included in vibrations that occur in the housing due to operation of the deflection device. The sensor system according to any one of claims 8 to 11.

13. The vibration modes include odd-order vibration modes. The sensor system of claim 12.

14. The vibration absorbing device is an intermediate member having a first surface facing the housing across a first gap and a second surface facing the support body across a second gap; a first vibration absorbing device disposed between the first surface of the intermediate member and the housing; a second vibration absorbing device disposed between the second surface of the intermediate member and the support; It is equipped with the pair of magnetized members are disposed at least within the first vibration absorbing device, A sensor system according to any one of claims 8 to 13.

15. the second vibration absorbing device is disposed so as not to overlap at least a portion of the first vibration absorbing device when viewed from a normal direction of the first surface of the intermediate member. The sensor system of claim 14.

16. The intermediate member has an opening that communicates the first gap with the second gap.

16. The sensor system according to claim 14 or 15.

17. The monitoring device is a mobile object.

17. A sensor system according to any one of claims 8 to 16.

18. The monitoring device includes a light chamber that houses a light source that emits visible light, The housing is configured to be housed in the lamp chamber.

18. A sensor system according to any one of claims 8 to 17.

19. A sensor system mounted on a monitoring device, a sensor for detecting an object located in a detection direction; a deflection device that periodically changes the detection direction; a housing containing the sensor and the deflection device; a vibration absorbing device disposed between a support constituting a part of the monitoring device and the housing; It is equipped with The vibration absorbing device is a pair of members arranged to face each other in a first direction; a cavity that accommodates at least a portion of the pair of members while allowing displacement of the pair of members in the first direction; a control device that controls the amount of fluid contained in the cavity so as to form a gap between the pair of members; Equipped with Sensor system.

20. a first detection device that outputs a first detection signal corresponding to a physical quantity related to a change that occurs in the housing as the deflection device operates; the control device feedback-controls the amount of the fluid based on the first detection signal.

20. The sensor system of claim 19.

21. the first detection device is disposed at a position that avoids a node of a vibration mode of a resonant frequency included in vibrations that occur in the housing due to operation of the deflection device; The sensor system of claim 20.

22. a second detection device that outputs a second detection signal corresponding to a state of the monitoring device; the control device feedforward controls the amount of the fluid based on the second detection signal.

22. A sensor system according to any one of claims 19 to 21.

23. the pair of members are arranged at positions that avoid nodes of a vibration mode of a resonant frequency included in vibrations that occur in the housing due to operation of the deflection device.

23. A sensor system according to any one of claims 19 to 22.

24. The vibration modes include odd-order vibration modes.

24. The sensor system of claim 23.

25. The pair of members are magnetized to the same polarity.

25. A sensor system according to any one of claims 19 to 24.

26. the vibration absorber includes a restricting member disposed between the pair of members and restricting displacement of the pair of members in the first direction; 26. A sensor system according to any one of claims 19 to 25.

27. The vibration absorbing device is an intermediate member having a first surface facing the housing across a first gap and a second surface facing the support body across a second gap; a first vibration absorbing device disposed between the first surface of the intermediate member and the housing; a second vibration absorbing device disposed between the second surface of the intermediate member and the support; It is equipped with the pair of members are disposed within the first vibration absorbing device; 27. A sensor system according to any one of claims 19 to 26.

28. the second vibration absorbing device is disposed so as not to overlap at least a portion of the first vibration absorbing device when viewed from a normal direction of the first surface of the intermediate member.

28. The sensor system of claim 27.

29. The intermediate member has an opening that communicates the first gap with the second gap.

29. A sensor system according to claim 27 or 28.

30. The monitoring device is a mobile object.

30. A sensor system according to any one of claims 19 to 29.

31. The monitoring device includes a light chamber that houses a light source that emits visible light, The housing is configured to be housed in the lamp chamber.

31. A sensor system according to any one of claims 19 to 30.

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