Sensor device

Abstract

A sensor device (1) comprises an ultrasonic sensor (10) and an exterior member (20). The ultrasonic sensor (10) has an entry / exit (11) through which ultrasonic waves enter and exit. An opening portion (21) is formed so as to be connected to the entry / exit (11). A first pipe portion (22) communicates with the opening portion (21). A second pipe portion (23) communicates with the opening portion (21). The first pipe portion (22) has a first open end (22a) that opens on the opposite side to the opening portion (21). The second pipe portion (23) has a second open end (23a) that opens on the opposite side to the opening portion (21). A first direction (D1), which is a direction obtained by extending a first axis (A1), which is the central axis of the first pipe portion (22), outward from the first open end (22a), and a second direction (D2), which is a direction obtained by extending a second axis (A2), which is the central axis of the second pipe portion (23), outward from the second open end (23a), are non-parallel to each other.

Description

Sensor Device

[0001] The present disclosure relates to a sensor device.

[0002] Japanese Patent Laid-Open Publication No. 2007-255924 (Patent Document 1) discloses an ultrasonic sensor and a protective member for the ultrasonic sensor. The protective member includes a plurality of receiving holes, a plurality of transmitting holes, and a plurality of communication paths. The receiving holes are open in different directions. The transmitting holes correspond to the receiving holes. The communication paths connect each receiving hole to its corresponding transmitting hole.

[0003] Japanese Patent Application Laid-Open No. 2007-255924

[0004] The protection device disclosed in Patent Document 1 has multiple receiving holes. However, these holes are provided for the purpose of improving the sensitivity of the ultrasonic sensor when detecting ultrasonic waves reflected from a single obstacle. With the protection device, it is difficult for a single ultrasonic sensor to detect two objects located in different directions from the protection device.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a sensor device that can easily detect two objects located in different directions from the sensor device using a single ultrasonic sensor.

[0006] A sensor device according to the present disclosure includes an ultrasonic sensor and an exterior member. The ultrasonic sensor is configured to be able to transmit and receive ultrasonic waves. The ultrasonic sensor has an entrance / exit for the entry and exit of ultrasonic waves. The exterior member has an opening, a first pipe portion, and a second pipe portion. The opening is formed to be connected to the entrance / exit. The first pipe portion communicates with the opening portion. The second pipe portion communicates with the opening portion. The first pipe portion has a first open end that opens on the opposite side from the opening portion. The second pipe portion has a second open end that opens on the opposite side from the opening portion. A first direction, which is a direction in which a first axis that is a central axis of the first pipe portion extends outward from the first open end, and a second direction, which is a direction in which a second axis that is a central axis of the second pipe portion extends outward from the second open end, are non-parallel to each other.

[0007] With the above configuration, it is possible to easily detect two objects located in a first direction and a second direction that are different from each other, using a single ultrasonic sensor.

[0008] According to the present disclosure, two objects to be detected that are located ahead of each other in different directions as viewed from the sensor device can be easily detected by a single ultrasonic sensor.

[0009] 1 is a perspective view showing a sensor device according to an embodiment of the present disclosure from above; FIG. 2 is a perspective view showing a sensor device according to an embodiment of the present disclosure from below; FIG. 3 is a cross-sectional view of the sensor device of FIG. 2 as viewed from the direction of the arrows III-III; FIG. 4 is a partial cross-sectional view showing a portion of a sensor device according to an embodiment of the present disclosure together with two detected objects; FIG. 5 is a block diagram schematically showing a circuit configuration of a sensor device according to an embodiment of the present disclosure; FIG. 6 is a flowchart showing an example of a processing flow of a processor of the sensor device; FIG. 7 is a schematic graph showing a time change in signal strength of ultrasonic waves received after an ultrasonic sensor starts transmitting ultrasonic waves; FIG. 8 is a graph showing an example of a time change in a first signal; FIG. 9 is a graph showing an example of a time change in only a reverberation signal of ultrasonic waves received by an ultrasonic sensor; FIG. 10 is a graph showing an example of a time change in a corrected first signal; FIG. 11 is a cross-sectional view showing an example of a state in which a sensor device according to an embodiment of the present disclosure is located at the upper step of a step; FIG. 12 is an example of a graph showing first signal data for each type of first detected object; FIG. 13 is a graph showing an example of a time change in a second signal; and FIG. 14 is another graph showing a time change in the second signal.

[0010] A sensor device according to an embodiment of the present disclosure will be described below. In the following description of the embodiment, the same or corresponding parts in the drawings will be denoted by the same reference numerals, and description thereof will not be repeated.

[0011] Fig. 1 is a perspective view showing a sensor device according to an embodiment of the present disclosure from above. Fig. 2 is a perspective view showing a sensor device according to an embodiment of the present disclosure from below. Fig. 3 is a cross-sectional view of the sensor device of Fig. 2 as viewed from the direction of the arrow III-III. Fig. 4 is a partial cross-sectional view showing a portion of a sensor device according to an embodiment of the present disclosure together with two detected objects. Fig. 4 is illustrated in the same cross-sectional view as Fig. 3.

[0012] 1 to 4 , a sensor device 1 according to an embodiment of the present disclosure is configured to be movable. The sensor device 1 is a mobile robot having a sensor function, more specifically, a mobile cleaning robot having a sensor function. However, the sensor device 1 may be a device different from these robots.

[0013] The sensor device 1 includes an ultrasonic sensor 10, an exterior member 20, one or more protrusions 30, and a housing 40. As shown in Figures 3 and 4, the ultrasonic sensor 10 is disposed inside the housing 40. The ultrasonic sensor 10 is configured to be able to transmit and receive ultrasonic waves. The ultrasonic sensor 10 has an entrance / exit 11 through which ultrasonic waves enter and exit.

[0014] The ultrasonic sensor 10 includes a substrate 12 and an element 13. The entrance / exit 11 is a through-hole formed in the substrate 12. The element 13 is provided on the substrate 12. The element 13 covers the entrance / exit 11. The element 13 is, for example, an acoustic MEMS element. "MEMS" is an abbreviation for Micro Electro Mechanical Systems. "Acoustic MEMS element" is a general term for MEMS microphones, pMUTs (piezoelectric micro-machined ultrasonic transducers), MEMS speakers, and the like. The element 13 has a vibrating part (not shown) including a piezoelectric material. When a driving voltage is input to the vibrating part, the vibrating part vibrates. In this way, the ultrasonic sensor 10 transmits ultrasonic waves. When ultrasonic waves strike the vibrating part and vibrate, a voltage signal is output. In this way, the ultrasonic sensor 10 receives ultrasonic waves. The frequencies of ultrasonic waves that can be transmitted and received by the ultrasonic sensor 10 will be described later.

[0015] The entrance 11 in the ultrasonic sensor 10 is not limited to a through-hole formed in the substrate 12. For example, the entrance 11 may be provided on the opposite side of the substrate 12 from the element 13.

[0016] 1 to 4 , the exterior member 20 is attached to the housing 40 so that a portion of the exterior member 20 is exposed to the outside. The exterior member 20 has an opening 21, a first pipe portion 22, and a second pipe portion 23.

[0017] The opening 21 is disposed inside the housing 40. The opening 21 is formed so as to be connected to the entrance 11. Specifically, the opening 21 contacts the peripheral portion of the ultrasonic sensor 10 around the entrance 11. The opening 21 contacts the substrate 12. The opening 21 is located on the opposite side of the substrate 12 from the element 13. The substrate 12 may be fixed directly to the exterior member 20, or may be fixed to the exterior member 20 via another fixing member (not shown).

[0018] The first pipe section 22 communicates with the opening 21. The first pipe section 22 has a first open end 22a that opens on the side opposite the opening 21. The first pipe section 22 increases in diameter from the opening 21 toward the first open end 22a. Note that the first pipe section 22 does not necessarily have to increase in diameter as described above. The first open end 22a is exposed to the outside of the sensor device 1.

[0019] The second pipe section 23 communicates with the opening 21. The second pipe section 23 has a second open end 23a that opens on the side opposite the opening 21. The second pipe section 23 increases in diameter from the opening 21 toward the second open end 23a. Note that the second pipe section 23 does not have to increase in diameter as described above. The second open end 23a is exposed to the outside of the sensor device 1. A portion of the first pipe section 22 on the opening 21 side and a portion of the second pipe section 23 on the opening 21 side communicate with each other.

[0020] The ultrasonic waves transmitted by the ultrasonic sensor 10 are dispersed at the opening 21 and at the point where a portion of the first pipe 22 on the opening 21 side communicates with a portion of the second pipe 23 on the opening 21 side. As described above, one of the dispersed ultrasonic waves passes through the opening 21 and the first pipe 22 and is further transmitted to the outside from the first open end 22a. The ultrasonic waves are then reflected by a first detection object O1 (see FIGS. 3 and 4 ), such as a floor. The reflected ultrasonic waves pass again from the first open end 22a through the first pipe 22 and the opening 21 to reach the ultrasonic sensor 10. As a result, the ultrasonic sensor 10 receives the ultrasonic waves reflected by the first detection object O1.

[0021] Meanwhile, the other dispersed ultrasonic wave passes through the opening 21 and the second pipe portion 23 and is further transmitted to the outside from the second open end 23a. The ultrasonic wave transmitted to the outside from the second open end 23a is then reflected by a second detection object O2 (see FIG. 4 ), such as an obstacle. The reflected ultrasonic wave passes again from the second open end 23a through the second pipe portion 23 and the opening 21 and reaches the ultrasonic sensor 10. As a result, the ultrasonic sensor 10 receives the ultrasonic wave reflected by the second detection object O2.

[0022] Here, the frequency of the ultrasonic waves transmitted from the ultrasonic sensor 10 will be described. The frequency of the ultrasonic waves is preferably 100 kHz or less. A frequency of 100 kHz or less allows the ultrasonic waves to propagate with a certain degree of spread. Consequently, dispersion of the ultrasonic waves can be prevented from being biased toward either the first pipe portion 22 or the second pipe portion 23. Furthermore, a frequency of 100 kHz or less can prevent attenuation of the ultrasonic waves propagating through the first pipe portion 22 and the second pipe portion 23. From the viewpoint of efficiently propagating the ultrasonic waves to both the first pipe portion 22 and the second pipe portion 23, it is also preferable that the frequency of the ultrasonic waves be lower than 100 kHz. For example, the frequency of the ultrasonic waves may be 80 kHz or less, 60 kHz or less, or 40 kHz or less.

[0023] A mesh filter may be provided inside either or both of the first pipe section 22 and the second pipe section 23. This allows ultrasonic waves to propagate inside the pipe section while suppressing the intrusion of foreign matter from outside the sensor device 1. Alternatively, a membrane filter may be provided inside either or both of the first pipe section 22 and the second pipe section 23. This prevents liquid from entering the sensor device 1 from outside, and allows ultrasonic waves to propagate inside the pipe section due to the vibration of the membrane filter.

[0024] Next, the first axis A1, which is the central axis of the first pipe portion 22, and the second axis A2, which is the central axis of the second pipe portion 23, will be described. In this embodiment, the first axis A1 is a straight line. However, the first axis A1 does not have to be a straight line. The first pipe portion 22 may extend so that a portion of the first axis A1 is bent. The first pipe portion 22 may extend so that a portion or all of the first axis A1 is curved. Also, in this embodiment, the second axis A2 is a straight line. However, the second axis A2 does not have to be a straight line. The second pipe portion 23 may extend so that a portion of the second axis A2 is bent. The second pipe portion 23 may extend so that a portion or all of the second axis A2 is curved.

[0025] In this embodiment, the length L1 of the first axis A1 is shorter than the length L2 of the second axis A2. The length L1 of the first axis A1 is not particularly limited. For example, the length L1 of the first axis A1 is 5 mm or more, 10 mm or more, or 15 mm or more. For example, the length L1 of the first axis A1 is 40 mm or less, 35 mm or less, or 30 mm or less.

[0026] The length L2 of the second axis A2 is not particularly limited. For example, the length L2 of the second axis A2 is 20 mm or more, 25 mm or more, or 30 mm or more. For example, the length L2 of the second axis A2 is 100 mm or less, 80 mm or less, or 60 mm or less.

[0027] The first direction D1, which is the direction in which the first axis A1 extends outward from the first open end 22 a, and the second direction D2, which is the direction in which the second axis A2 extends outward from the second open end 23 a, are non-parallel to each other. The angle between the first direction D1 and the second direction D2 may be 30 degrees or more, 45 degrees or more, 75 degrees or more, 80 degrees or more, 85 degrees or more, or 90 degrees or more.

[0028] The second direction D2 is, for example, a direction in which the sensor device 1, which is a mobile robot, moves. In other words, the second direction D2 is, for example, a front direction of the sensor device 1. In this embodiment, when the first direction D1 is parallel to the vertical direction, the second direction D2 is parallel to the horizontal direction.

[0029] The exterior member 20 may further include one or more other pipe portions. The one or more other pipe portions may include a third pipe portion having a configuration similar to that of the second pipe portion. However, it is preferable that the length of the central axis of the third pipe portion is different from the length L2 of the second axis A2.

[0030] 2 to 4, in this embodiment, the multiple protrusions 30 protrude along the first direction D1. The multiple protrusions 30 protrude from the housing 40. At least one of the multiple protrusions 30 may protrude from the exterior member 20. Specifically, the multiple protrusions 30 may be multiple rollers. When the sensor device 1 moves, the multiple protrusions 30 come into contact with the ground. At least one of the multiple protrusions 30, which are multiple rollers, may be configured to be rotationally driven.

[0031] The multiple protrusions 30 are configured so that when the multiple protrusions 30 contact the first object O1, the sum of the length L1 of the first axis A1 and the distance D from the first opening end 22a to the first object O1 is a constant dimension shorter than the length L2 of the second axis A2. Specifically, when the surface of the first object O1 is flat, the multiple protrusions 30 are configured to be able to contact the surface of the first object O1 simultaneously. When the multiple protrusions 30 contact the flat surface of the first object O1 simultaneously, the sum of the length L1 and the distance D is a constant dimension shorter than the length L2. For example, the protrusion length of the multiple protrusions 30 in the first direction D1 may be approximately equal to the distance D. In this case, when the multiple protrusions 30 contact the flat surface of the first object O1 simultaneously, the first direction D1 is perpendicular to the surface.

[0032] The dimension of distance D is not particularly limited, and may be, for example, 2 mm or more, 3 mm or more, or 5 mm or more. The dimension of distance D may be, for example, 20 mm or less, 15 mm or less, or 12 mm or less.

[0033] Next, an example of processing of the output signal of the ultrasonic sensor 10 in the sensor device 1 will be described. FIG. 5 is a block diagram schematically illustrating a circuit configuration of a sensor device according to an embodiment of the present disclosure. As shown in FIG. 5, in this embodiment, the sensor device 1 further includes a processor 70 and a memory 80 as a control circuit. The processor 70 is connected to the element 13 of the ultrasonic sensor 10 and is configured to be able to transmit an input signal to the ultrasonic sensor 10 based on a program stored in the memory 80. The processor 70 is also configured to be able to receive an output signal from the ultrasonic sensor 10. Note that the control circuit may be mounted on the substrate 12.

[0034] In addition to the control circuit described above, the sensor device 1 may further include a main body control circuit 91 and an actuator 92. The main body control circuit 91 controls the actuator 92, such as an electric motor. The actuator 92 drives the multiple protrusions 30 (rollers). The processor 70 and the processor of the main body control circuit 91 are configured to be able to communicate with each other. Information obtained by the ultrasonic sensor 10 is transmitted from the processor 70 to the processor of the main body control circuit 91. The processor of the main body control circuit 91 may control the actuator 92 based on the information. Note that the processor according to the present disclosure may be the processor of the main body control circuit 91.

[0035] 6 is a flowchart showing an example of the processing flow of the processor of the sensor device. As shown in Fig. 6, the processor 70 transmits an input signal to the ultrasonic sensor 10 to cause the ultrasonic sensor 10 to emit ultrasonic waves (step S1). After transmitting the input signal, the processor 70 receives an output signal output by the ultrasonic sensor 10 based on the ultrasonic waves received by the ultrasonic sensor 10 (step S2).

[0036] Then, the processor 70 acquires information about the first detected object O1 located in the first direction D1 as viewed from the first opening end 22a based on the first signal received from the output signals when the elapsed time from the start of transmission of the input signal is less than or equal to a threshold value (first threshold value) (step S3).

[0037] FIG. 7 is a schematic graph showing the time change in the signal strength of the received ultrasonic waves after the ultrasonic sensor starts transmitting the ultrasonic waves. The first threshold value is, for example, the time (2 × [L2] / c) calculated by dividing twice the length L2 of the second axis A2 by the speed of sound c. During this time, the ultrasonic waves reflected by the second object O2 cannot reach the ultrasonic sensor 10 (see FIG. 4 ). As described above, the first pipe portion 22 and the multiple protrusions 30 are configured so that the relationship (([L1] + [D]) < [L2]) holds. Therefore, the ultrasonic waves reflected by the first object O1 reach the ultrasonic sensor 10 within the time (2 × [L2] / c). Therefore, as shown in FIG. 7 , the first signal does not include the second signal, which is a signal due to the ultrasonic waves reflected by the second object O2, and is a signal due to the ultrasonic waves reflected by the first object O1.

[0038] The processor 70 may receive, as the first signal, an output signal that is received after the elapsed time from the start of transmission of the input signal becomes equal to or greater than a second threshold. The second threshold is, for example, a time calculated by dividing twice the sum of the length L1 of the first axis A1 and the distance D from the first opening end 22a to the first detection object O1 by the speed of sound c (2 × ([L1] + [D]) / c). Within this time, ultrasonic waves reflected by the second detection object O2 cannot, in principle, reach the ultrasonic sensor 10 (see FIGS. 4 and 7).

[0039] Specifically, in step S3, the processor 70 acquires the time-dependent signal strength of the first signal (hereinafter, sometimes referred to as "first signal data") based on the first signal. This first signal data may be used as is to acquire information about the first detected object O1, or the first signal data may be corrected.

[0040] Correcting the first signal data is useful mainly when the reverberation of ultrasonic waves within the first pipe section 22 is relatively large. FIG. 8 is a graph showing an example of a time change in the first signal. When the reverberation is relatively large, as shown in FIG. 8, the first signal based on ultrasonic waves reflected from the first detection object O1, which the ultrasonic sensor 10 originally intended to receive, may overlap with the signal due to the reverberation. FIG. 9 is a graph showing an example of a time change in only the reverberation signal of ultrasonic waves received by the ultrasonic sensor. For example, by transmitting and receiving ultrasonic waves when the first detection object O1 is not present within a predetermined distance in the first direction D1, signal data consisting essentially of the reverberation signal, as shown in FIG. 9, can be obtained. This signal data consisting essentially of the reverberation signal may be stored in advance in the memory 80.

[0041] Fig. 10 is a graph showing an example of the change over time of the corrected first signal. By subtracting the signal intensity for each time period in the signal data containing only the reverberation signal stored in memory 80 from the first signal data (see Fig. 8), it is possible to obtain corrected first signal data from which the reverberation signal component has been removed, as shown in Fig. 10. Note that the graphs in the example shown in Figs. 8 to 10 show signal intensity when, in the sensor device 1 according to this embodiment, the length L1 is 20 mm, the length L2 is 55 mm, the distance D is 10 mm, and the frequency of the ultrasonic waves transmitted by the ultrasonic sensor 10 is approximately 300 kHz.

[0042] The above-described information regarding the first object O1 includes information regarding whether the first object O1 is in contact with the protrusion 30. For example, the first object O1 (an object present in the first direction D1 as viewed from the first opening end 22a) may not be in contact with the protrusion 30. More specifically, when the sensor device 1 is a mobile cleaning robot with a sensor function as in the present embodiment, the protrusion 30 may be in contact with the upper step (top of a cliff) of a step, and the lower step (below the cliff) of the step may be located beyond the first direction D1 as viewed from the first opening end 22a. The information regarding the first object O1 may include such information. For example, if the maximum signal strength in the corrected first data is not substantially recognized, the processor 70 may determine that the first object O1 is not in contact with the protrusion 30.

[0043] The information about the first object O1 further includes information about the type of surface of the first object O1 abutting the protrusion 30. When the first object O1 is a house floor, the information about the first object O1 is information about the type of material of the floor surface. FIG. 11 is a cross-sectional view showing an example of a state in which a sensor device according to an embodiment of the present disclosure is located on the upper level of a step. FIG. 12 is an example of a graph showing first signal data for each type of first object. When the sensor device 1 is located on the upper level of a step and the first object O1 is not within a predetermined range in the first direction D1 beyond the first opening end 22a as shown in FIG. 11, almost no peak is observed in the first signal data, as shown in FIG. 12. Furthermore, when the material of the first object O1 is tile or wood, the maximum intensity of the first signal data is greater than the maximum intensity of the first signal data when the material of the first object O1 is carpet. This is because carpet has a lower ultrasonic reflectivity than tile and wood. Therefore, by referring to a database showing the relationship between materials and maximum intensities that is stored in advance in memory 80, information about the surface type of the first detected object O1 can be obtained from the value of the maximum intensity in the first signal data. Note that the graphs in the examples shown in Figure 12 and Figures 13 and 14 described below show signal intensities in the sensor device 1 according to this embodiment when the length L1 is 20 mm, the length L2 is 55 mm, the distance D is 10 mm, and the frequency of the ultrasonic waves transmitted by the ultrasonic sensor 10 is approximately 40 kHz.

[0044] Then, as shown in FIG. 6, the processor 70 calculates the distance X between the second detection object O2 located in the second direction D2 as viewed from the second opening end 23a and the second opening end 23a based on the second signal received from the output signals when the elapsed time from the start of transmission of the input signal exceeds a threshold value (first threshold value) (step S4).

[0045] Specifically, the processor 70 calculates the distance X using time of flight (TOF). For example, the distance X is calculated by multiplying half the time t from the transmission of the ultrasonic signal to the reception of the second signal by the sound speed c, and then subtracting the dimension L2 from the calculated value (t / 2×c−[L2]). FIG. 13 is a graph showing an example of the change in the second signal over time. FIG. 14 is a graph showing another example of the change in the second signal over time. However, in FIGS. 13 and 14, the horizontal axis is converted from the value calculated by multiplying half the time t by the sound speed c, and then subtracting the dimension L2 (t / 2×c−[L2]). As shown in FIGS. 13 and 14, the intensity peak position of the second signal differs depending on the distance X between the second object O2 and the second opening end 23a. 13 and 14, it can be seen that the distance X can be calculated approximately based on the timing of the intensity peak of the second signal. In the case where the sensor device 1 is a mobile robot as in this embodiment, the distance X can be detected as the distance to an obstacle in the traveling direction.

[0046] Furthermore, by designing the first pipe section 22 and the second pipe section 23 so that L2 is a value sufficiently larger than L1+D, the ultrasonic sensor 10 can receive the ultrasonic waves reflected from the second detection object O2 after the first signal and the reverberation signal have sufficiently attenuated. Furthermore, by designing the first pipe section 22 and the second pipe section 23 so that L2 is a value sufficiently larger than L1+D, even when the second detection object O2 is present in close proximity to the second opening end 23a (when the distance X is 0), the processor 70 can easily distinguish the second signal from the first signal and receive it (see FIG. 13 ).

[0047] As described above, in the sensor device 1 of this embodiment, the first direction D1, which is the direction in which the first axis A1, which is the central axis of the first pipe section 22, extends outward from the first opening end 22a, and the second direction D2, which is the direction in which the second axis A2, which is the central axis of the second pipe section 23, extends outward from the second opening end 23a, are non-parallel to each other.

[0048] With the above configuration, two objects located in the first direction D1 and the second direction D2, which are different from each other, can be detected by one ultrasonic sensor 10. In other words, two objects located in different directions from the sensor device 1 can be easily detected by one ultrasonic sensor 10.

[0049] Furthermore, the angle between the first direction D1 and the second direction D2 is 45 degrees or more. With this configuration, the sensor device 1 can detect two different objects that are spaced apart from each other by 45 degrees or more with the sensor device 1 at the center.

[0050] Furthermore, the angle between the first direction D1 and the second direction D2 is 90 degrees or more. With this configuration, the sensor device 1 can detect two different objects that are spaced apart from each other by 90 degrees or more with the sensor device 1 at the center.

[0051] Furthermore, a part of the first pipe portion 22 on the opening 21 side and a part of the second pipe portion 23 on the opening 21 side are in communication with each other. With this configuration, the size of the exterior member 20 can be reduced.

[0052] The first axis A1 is a straight line. This configuration can prevent the intensity of ultrasonic waves passing through the first pipe section 22 from attenuating. The second axis A2 is a straight line. This configuration can prevent the intensity of ultrasonic waves passing through the second pipe section 23 from attenuating.

[0053] The first pipe 22 also has a diameter that increases from the opening 21 toward the first open end 22a. This configuration suppresses reverberation of ultrasonic waves passing through the first pipe 22, making it easier to detect ultrasonic waves received by the ultrasonic sensor 10. The second pipe 23 also has a diameter that increases from the opening 21 toward the second open end 23a. This configuration suppresses reverberation of ultrasonic waves passing through the second pipe 23, making it easier to detect ultrasonic waves received by the ultrasonic sensor 10. The first pipe 22 does not have to have a diameter that increases as described above. The second pipe 23 does not have to have a diameter that increases as described above.

[0054] Furthermore, the length L1 of the first axis A1 is shorter than the length L2 of the second axis A2. This allows the sum of the length L1 of the first axis A1 and the distance D from the first object O1 located in the first direction D1 as viewed from the first opening end 22a to the first opening end 22a to be shorter than the length L2 of the second axis. Note that when the sum of the length L1 and the distance D is shorter than the length L2 as described above, the time at which the ultrasonic sensor 10 receives the ultrasonic wave reflected from the first object O1 and the time at which the ultrasonic sensor 10 receives the ultrasonic wave reflected from the second object O2 located in the second direction D2 as viewed from the second opening end 23a are different from each other, in response to a single transmission of ultrasonic waves by the ultrasonic sensor 10. Therefore, both the first object O1 and the second object O2 can be detected by the two ultrasonic waves received in response to a single transmission of ultrasonic waves.

[0055] The sensor device 1 further includes a protrusion 30. The protrusion 30 protrudes along a first direction D1. The protrusion 30 is configured so that, when the protrusion 30 abuts against the first object O1, the sum of the length L1 of the first axis A1 and the distance D from the first opening end 22a to the first object O1 is a constant dimension that is shorter than the length L2 of the second axis A2. As a result, when the protrusion 30 abuts against the first object O1, both the first object O1 and the second object O2 can be detected by the two ultrasonic waves received in response to a single ultrasonic wave transmission.

[0056] The sensor device 1 further includes a processor 70. The processor 70 transmits an input signal to the ultrasonic sensor 10 to cause the ultrasonic sensor 10 to emit ultrasonic waves. After transmitting the input signal, the processor 70 receives an output signal output by the ultrasonic sensor 10 based on the ultrasonic waves received by the ultrasonic sensor 10. The processor 70 acquires information about a first object O1 located in a first direction D1 as viewed from the first opening end 22a based on a first signal received when the elapsed time from the start of transmission of the input signal is equal to or less than a threshold value among the output signals. The processor 70 calculates a distance X between the second opening end 23a and a second object O2 located in a second direction D2 as viewed from the second opening end 23a based on a second signal received when the elapsed time from the start of transmission of the input signal exceeds a threshold value among the output signals. This allows a single ultrasonic sensor 10 to not only measure the distance X between the second object O2 and the second opening end 23a but also acquire information about the first object O1 abutting the protrusion 30.

[0057] Furthermore, the information regarding the first object O1 includes information regarding whether the first object O1 is in contact with the protrusion 30. In this manner, by providing the protrusion 30 as described above, it is possible to measure the distance X to the second object O2 and obtain information of a different type from the distance X.

[0058] Furthermore, the information about the first object O1 further includes information about the type of surface of the first object O1 that abuts against the protrusion 30. In this way, by providing the protrusion 30 as described above and by making the sum of the length L1 and the distance D shorter than the length L2, it is possible to measure the distance X to the second object O2 and obtain information of a type different from the distance X.

[0059] (Additional Note) As described above, the present embodiment includes the following disclosures.

[0060] <1> A sensor device comprising: an ultrasonic sensor; and an exterior member; the ultrasonic sensor is configured to be able to transmit and receive ultrasonic waves and has an entrance / exit for the entry and exit of ultrasonic waves; the exterior member has: an opening formed to connect to the entrance / exit; a first pipe portion communicating with the opening; and a second pipe portion communicating with the opening; the first pipe portion has a first open end that opens on the opposite side to the opening; and the second pipe portion has a second open end that opens on the opposite side to the opening; a first direction that is a direction in which a first axis that is a central axis of the first pipe portion extends outward from the first open end, and a second direction that is a direction in which a second axis that is a central axis of the second pipe portion extends outward from the second open end, are non-parallel to each other.

[0061] <2> The sensor device according to <1>, wherein the angle between the first direction and the second direction is 45 degrees or more.

[0062] <3> The sensor device according to <2>, wherein the angle between the first direction and the second direction is 90 degrees or more.

[0063] <4> The sensor device according to any one of <1> to <3>, wherein a portion of the first pipe section on the opening side and a portion of the second pipe section on the opening side are in communication with each other.

[0064] <5> The sensor device according to any one of <1> to <4>, wherein the first axis is a straight line, and the second axis is a straight line.

[0065] <6> The sensor device according to any one of <1> to <5>, wherein the first pipe portion increases in diameter from the opening toward the first open end, and the second pipe portion increases in diameter from the opening toward the second open end.

[0066] <7> The sensor device according to any one of <1> to <6>, wherein the length of the first axis is shorter than the length of the second axis.

[0067] <8> The sensor device according to <7>, further comprising a protruding portion that protrudes along the first direction, wherein the protruding portion is configured such that when the protruding portion abuts against a first object to be detected, the sum of the length of the first axis and the distance from the first opening end to the first object to be detected is a constant dimension that is shorter than the length of the second axis.

[0068] <9> The sensor device according to <8>, further comprising a processor, wherein the processor transmits an input signal to the ultrasonic sensor to cause the ultrasonic sensor to emit ultrasonic waves, and the processor receives an output signal output by the ultrasonic sensor based on the ultrasonic waves received by the ultrasonic sensor after transmitting the input signal, and the processor acquires information about the first object located in the first direction as viewed from the first opening end based on a first signal among the output signals that is received when the elapsed time from the start of transmission of the input signal is equal to or less than a threshold, and the processor calculates a distance between the second opening end and a second object located in the second direction as viewed from the second opening end based on a second signal among the output signals that is received when the elapsed time from the start of transmission of the input signal exceeds the threshold.

[0069] <10> The sensor device according to <9>, wherein the information relating to the first detected object includes information relating to whether the first detected object is in contact with the protrusion.

[0070] <11> The sensor device according to <9> or <10>, wherein the information about the first object further includes information about a type of surface of the first object that contacts the protrusion.

[0071] In the above description of the embodiments, combinable configurations may be combined with each other. The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0072] 1 Sensor device, 10 Ultrasonic sensor, 11 Entrance / exit, 12 Board, 13 Element, 20 Exterior member, 21 Opening, 22 First pipe portion, 22a First opening end, 23 Second pipe portion, 23a Second opening end, 30 Protrusion, 40 Housing, 70 Processor, 80 Memory, 91 Main body control circuit, 92 Actuator, O1 First detected object, O2 Second detected object.

Claims

1. A sensor device comprising: an ultrasonic sensor; and an exterior member; wherein the ultrasonic sensor is configured to be able to transmit and receive ultrasonic waves and has an entrance and exit for the entry and exit of ultrasonic waves; the exterior member has an opening formed to connect to the entrance and exit, a first pipe section communicating with the opening, and a second pipe section communicating with the opening; the first pipe section has a first opening end that opens on the opposite side to the opening; and the second pipe section has a second opening end that opens on the opposite side to the opening; a first direction in which a first axis that is the central axis of the first pipe section extends outward from the first opening end, and a second direction in which a second axis that is the central axis of the second pipe section extends outward from the second opening end are non-parallel to each other.

2. The sensor device according to claim 1, wherein the angle between the first direction and the second direction is 45 degrees or greater.

3. The sensor device according to claim 2, wherein the angle between the first direction and the second direction is 90 degrees or greater.

4. A sensor device according to any one of claims 1 to 3, wherein a portion of the opening side of the first pipe section and a portion of the opening side of the second pipe section are in communication with each other.

5. A sensor device according to any one of claims 1 to 4, wherein the first axis is a straight line, and the second axis is a straight line.

6. A sensor device as described in any one of claims 1 to 5, wherein the first pipe portion expands in diameter from the opening toward the first opening end, and the second pipe portion expands in diameter from the opening toward the second opening end.

7. A sensor device according to any one of claims 1 to 6, wherein the length of the first axis is shorter than the length of the second axis.

8. A sensor device as described in claim 7, further comprising a protruding portion that protrudes along the first direction, wherein the protruding portion is configured so that when the protruding portion abuts against a first object to be detected, the sum of the length of the first axis and the distance from the first opening end to the first object to be detected is a constant dimension that is shorter than the length of the second axis.

9. A sensor device as described in claim 8, further comprising a processor, wherein the processor transmits an input signal to the ultrasonic sensor to cause the ultrasonic sensor to emit ultrasonic waves, the processor receives an output signal output by the ultrasonic sensor based on the ultrasonic waves received by the ultrasonic sensor after transmitting the input signal, the processor acquires information about the first object located in the first direction as viewed from the first opening end based on a first signal among the output signals that is received when the elapsed time from the start of transmission of the input signal is equal to or less than a threshold, and the processor calculates the distance between the second opening end and a second object located in the second direction as viewed from the second opening end based on a second signal among the output signals that is received when the elapsed time from the start of transmission of the input signal exceeds the threshold.

10. The sensor device according to claim 9, wherein the information relating to the first object to be detected includes information relating to whether or not the first object to be detected is in contact with the protrusion.

11. A sensor device according to claim 9 or 10, wherein the information relating to the first object further includes information relating to the type of surface of the first object that abuts against the protrusion.

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