Ultrasonic sonar device

Abstract

To provide an ultrasonic sonar device that makes it easier to understand the ship's movements up to that point, in conjunction with the detection result image. [Solution] The system comprises: a detection result image generation means that generates a detection result image by projecting the detection results of a specific range of water from a ship onto a plane parallel to the horizontal plane; an acquisition means that acquires the ship's position information at unit time intervals; a track image generation means that generates a track image for drawing the ship's track within a specific range onto the detection result image based on the ship's position information acquired by the acquisition means; and a display control means that controls the display of the detection result image with the track drawn on it using the track image on a display device. The track image generation means generates a track image for drawing on the detection result image at a different scale than the detection result image, while aligning the track with the direction of the detection result image for a predetermined period of time.

Description

[Technical Field]

[0001] The present invention relates to an ultrasonic sonar apparatus. [Background Art]

[0002] An ultrasonic sonar apparatus that detects detection targets such as fish schools over a predetermined range in water through transmission and reception of ultrasonic waves is known. While a general fish finder detects a detection target in the vertical direction from a ship, an ultrasonic sonar apparatus can detect detection targets existing around the ship, such as horizontal detection and vertical section detection.

[0003] Here, in horizontal detection, a tilt angle (depression angle) is fixed to a predetermined angle as the transmission and reception direction of ultrasonic waves, and a scan angle (azimuth angle) is set to all angles (0° to 360°) or an angle within a predetermined range, whereby a predetermined range is defined as all or part of azimuths obliquely downward from a horizontal plane as viewed from a ship, and detection targets included in the predetermined range are detected. As ultrasonic sonar apparatuses that perform horizontal detection, for example, PPI sonars (searchlight sonars), scanning sonars, and the like are known.

[0004] These ultrasonic sonar apparatuses project, as a detection result of horizontal detection, the intensity of ultrasonic reflected waves reflected from each position included in a predetermined range onto a plane parallel to the horizontal plane, then display, on a display device, a circular (or sector-shaped with the position of the ship as the central angle) detection result image centered at the position of the ship, which is represented with a color corresponding to the intensity at each position. A user of the ultrasonic sonar apparatus can determine the presence or absence of a reaction of a detection target in the predetermined range, the direction of the reaction, the distance to the detection target, and the like, from the detection result image displayed by the ultrasonic sonar apparatus that performs horizontal detection. Then, the user can navigate the ship toward the detection target existing in the predetermined range.

[0005] Furthermore, some ultrasonic sonar devices of this type display the ship's track within the range shown in the horizontal detection image (for example, Patent Document 1). Users can compare the direction and distance at which the detected object's response appeared in the detection image with the ship's past movements on the detection image, enabling an approach to the detected object that takes into account the ship's movements due to tides, wind, etc.

[0006] In conventional ultrasonic sonar systems, when displaying a ship's track on the detection result image of horizontal detection, the track was displayed within the range indicated by the detection result image. That is, the scale of the track was matched to the scale corresponding to the range displayed on a plane parallel to the horizontal plane in the detection result image (hereinafter referred to as the "display range"). [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2025-013027 [Overview of the project] [Problems that the invention aims to solve]

[0008] However, the display range of the detection result image is set by the user according to the depth of the seabed (seabed, lakebed, etc.) within a predetermined range, and naturally, if the seabed is shallow, the display range of the detection result image will be narrower. Also, if the tilt angle of the ultrasonic transmission and reception direction is increased and ultrasonic waves are transmitted and received in a direction closer to the vertical, the display range of the detection result image will also be narrower. In this case, even if the ship's track is displayed in the detection result image, the track will only be displayed in a range close to the ship's current position, making it difficult to understand what kind of track the ship had followed before the detection result image. On the other hand, if the display range of the detection result image is wide, the user can understand the ship's track over that wide range, but it is difficult to grasp the ship's recent detailed movements, and it is difficult to consider the influence of tides and wind on the ship's recent movements.

[0009] This invention was made to solve the above-mentioned problems, and aims to provide an ultrasonic sonar device that makes it easier to understand the movement of a ship up to that point, in conjunction with the detection result image. [Means for solving the problem]

[0010] To achieve this objective, an ultrasonic sonar device according to a first aspect of the present invention includes: a transmitter / receiver unit that is attached to a ship and transmits ultrasonic waves over a predetermined range in the water set in all directions or a partial direction from the ship, and receives reflected ultrasonic waves reflected from each position in the water for each predetermined direction; a detection result image generation means that generates a detection result image showing the detection results in the water within a specific range from the ship projected onto a plane parallel to the horizontal plane based on the received signals for each predetermined direction generated based on the reflected waves received by the transmitter / receiver unit; and a means that generates a detection result image showing the detection results in each unit time for each unit time. The system comprises: an acquisition means for acquiring the position information of a vessel; a track image generation means for generating a track image for drawing the vessel's track within a specific range onto the detection result image based on the position information of the vessel acquired by the acquisition means; and a display control means for controlling the detection result image on which the track is drawn using the track image to be displayed on a display device. The track image generation means generates the track image for drawing the track onto the detection result image at a different scale than the detection result image, while aligning the track with the direction of the detection result image for a predetermined period of time.

[0011] Here, the transmitting and receiving unit is not limited to one that simultaneously transmits ultrasonic waves over a predetermined range in the water set in all directions or in some directions as viewed from the ship, and simultaneously receives reflected ultrasonic waves reflected from each position in the water in each predetermined direction, but also includes one that sequentially transmits beam-shaped ultrasonic waves while changing direction within a predetermined range, and receives reflected ultrasonic waves reflected from each position in the water in each of those directions.

[0012] An ultrasonic sonar device according to a second aspect of the present invention is an ultrasonic sonar device according to a first aspect, further comprising a scale setting receiving means for receiving in advance from the user the setting of the scale of the track in the track image generated by the track image generation means for a predetermined period of time.

[0013] An ultrasonic sonar device according to a third aspect of the present invention is an ultrasonic sonar device according to a first or second aspect, further comprising an instruction means for the user to indicate the start of the predetermined period.

[0014] An ultrasonic sonar device according to a fourth aspect of the present invention is an ultrasonic sonar device according to any of the first to third aspects, wherein the track image generation means terminates the predetermined period when a predetermined time has elapsed from the start of the predetermined period. [Effects of the Invention]

[0015] According to the ultrasonic sonar device of the first embodiment, ultrasonic waves are transmitted by a transmitting / receiving unit attached to a ship over a predetermined range in the water set in all directions or in some directions from the ship, and reflected ultrasonic waves reflected from each position in the water for each predetermined direction are received. Based on the reflected waves received by the transmitting / receiving unit, a reception signal is generated for each predetermined direction, and based on the reception signal, a detection result image is generated by a detection result image generation means, which projects the detection results in the water within a specific range from the ship onto a plane parallel to the horizontal plane. Meanwhile, the ship's position information is acquired by an acquisition means at each unit time. Based on the ship's position information acquired by the acquisition means, a track image is generated by a track image generation means for drawing the ship's track within the specific range shown in the detection result image onto the detection result image. The detection result image with the track drawn on it using the track image is then displayed on a display device under the control of a display control means. This allows users to compare the direction and distance at which the detected object's response appeared in the detection result image with the ship's past movements, based on the track drawn on the detection result image.

[0016] Furthermore, the track image generation means generates a track image for a predetermined period of time, which is drawn on the detection result image at a different scale than the detection result image, while aligning the track with the bearing of the detection result image. As a result, the display device shows the detection result image with a track drawn on it at a different scale than the detection result image. Therefore, if the scale of the track is smaller than the scale of the detection result image for a predetermined period of time, the user can confirm the ship's track in an area outside a specific range that could not be grasped with a track displayed at the scale of the detection result image. Also, if the scale of the track is larger than the scale of the detection result image for a predetermined period of time, the user can confirm the recent detailed movements of the ship that could not be grasped with a track displayed at the scale of the detection result image. Therefore, together with the detection result image, it has the effect of making it easier to understand the ship's movements up to that point.

[0017] The ultrasonic sonar device according to the second aspect of the present invention provides the following effects in addition to those of the ultrasonic sonar device according to the first aspect. Specifically, the scale of the track in the track image generated by the track image generation means for a predetermined period is set in advance by the user through the scale setting reception means. This has the effect of displaying the track at the desired scale set by the user on the detection result image for a predetermined period.

[0018] The ultrasonic sonar device according to the third aspect of the present invention provides the following effects in addition to those of the ultrasonic sonar device according to the first or second aspect: When instructed by the user via an instruction means, a predetermined period is started, and a track with a different scale from the detection result image is drawn on the detection result image and displayed on the display device. This has the effect of allowing the display device to show the detection result image and a track with a different scale according to the user's will.

[0019] According to the ultrasonic sonar device according to the fourth aspect of the present invention, in addition to the effects exerted by the ultrasonic sonar device according to any one of the first to third aspects, the following effect is exerted. That is, when a predetermined time has elapsed from the start of a predetermined period, the predetermined period is ended by the wake image generation means. As a result, if a predetermined time elapses after the display of the detection result image of the wake having a different scale from the detection result image is started, the scale of the detection result image is automatically adjusted without any operation by the user. There is an effect that the display can be returned to the detection result image on which the wake of the same scale is drawn. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] [Figure 1] 1 is a schematic diagram schematically showing a configuration of an ultrasonic sonar device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a side schematic view showing a state where underwater detection is performed by a ship equipped with the ultrasonic sonar device and position information of the ship is acquired. [Figure 3] FIG. 3 is a perspective schematic view showing a state when horizontal underwater detection is performed by the ultrasonic sonar device. [Figure 4] FIG. 4 is a cross-sectional view schematically showing a cross-section of a transmitting / receiving unit of the ultrasonic sonar device. [Figure 5] FIG. 5 is a block diagram showing an electrical configuration of the ultrasonic sonar device. [Figure 6] FIG. 6 is a flowchart showing horizontal detection processing executed by a CPU of a control device of the ultrasonic sonar device. [Figure 7] FIG. 7 is a flowchart showing wake generation processing executed by the CPU. [Figure 8] FIG. 8 is a flowchart showing display control processing executed by the CPU. [Figure 9] (a) is a diagram showing a ship's wake on the detection result image at the same scale as the detection result image in the ultrasonic sonar device, and (b) is a diagram showing the wake on the detection result image at a smaller scale than the detection result image in the ultrasonic sonar device. [Figure 10](a) is a diagram showing the ship's track on the detection result image at the same scale as the detection result image, as used by the ultrasonic sonar system, and (b) is a diagram showing the ship's track on the detection result image at a larger scale than the detection result image, as used by the ultrasonic sonar system. [Modes for carrying out the invention]

[0021] Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. The embodiments described below are all preferred specific examples of the present invention. Therefore, the numerical values, shapes, materials, components, arrangement positions of components, and connection configurations shown in the following embodiments are examples and are not intended to limit the present invention. Accordingly, among the components in the following embodiments, those not described in the independent claims representing the highest-level concept of the present invention will be described as optional components. Furthermore, in each figure, substantially identical components are denoted by the same reference numerals, and redundant explanations are omitted or simplified.

[0022] First, an overview of an ultrasonic sonar device 12, which is one embodiment of the present invention, will be described with reference to Figures 1 to 4. Figure 1 is a schematic diagram showing the configuration of the ultrasonic sonar device 12. Figure 2 is a schematic diagram showing from the side the state in which a ship 11 equipped with the ultrasonic sonar device 12 performs underwater detection and acquires the position information of the ship 11. Figure 3 is a schematic diagram showing a perspective view of the state when the ultrasonic sonar device 12 performs horizontal underwater detection. Figure 4 is a schematic cross-sectional view showing a cross-section of the transducer unit 16 of the ultrasonic sonar device 12.

[0023] As shown in Figures 1 to 3, the ultrasonic sonar device 12 is a PPI sonar (searchlight sonar) mounted on a ship 11, which has a sonar function to detect objects GF such as schools of fish in the water over a predetermined range around the ship 11. The PPI sonar emits (transmits) a narrow beam of ultrasonic waves TB, and the transducer 31 that receives the reflected waves from the objects GF etc. of the ultrasonic waves TB is configured to be rotatable or pivotable, and the device performs underwater detection around the ship 11 while changing the direction of irradiation of the ultrasonic waves TB.

[0024] The ultrasonic sonar device 12 is configured to perform at least horizontal detection as a sonar function. Horizontal detection involves detecting objects GF that are included within a predetermined range that is diagonally downward from the horizontal plane as viewed from the ship 11, in all directions or in part of the direction.

[0025] The ultrasonic sonar device 12 comprises a main unit 13, an operation button 14 provided on the main unit 13, a display device 15 integrally formed on the main unit 13, a transmitter / receiver unit 16 for transmitting and receiving ultrasonic TB, a lifting device 17 for raising and lowering the transmitter / receiver unit 16, and a GPS antenna 18 for receiving signals transmitted from GPS satellites S, which are artificial satellites for the Global Positioning System.

[0026] The main unit 13, which has operation buttons 14 and a display device 15, is located in the wheelhouse of the ship 11, and the GPS antenna 18 is fixed to the roof of the wheelhouse of the ship 11. The transmitter / receiver unit 16 and the lifting device 17 are located in the bottom of the ship 11. The transmitter / receiver unit 16 can be raised and lowered by the lifting device 17, allowing it to extend and retract from the bottom of the ship 11 into the water.

[0027] As shown in Figure 2, the ultrasonic sonar device 12 transmits (irradiates) a narrow beam of ultrasonic waves TB in one direction from the transmitting / receiving unit 16 with the transmitting / receiving unit 16 protruding from the bottom of the ship 11, and receives the reflected waves of ultrasonic waves TB reflected from the object to be detected GF or the seabed (seabed or lakebed) at the transmitting / receiving unit 16. The ultrasonic sonar device 12 does not necessarily have a lifting / lowering device 17, and the transmitting / receiving unit 16 may be fixed to the ship 11 in a position where ultrasonic waves TB can be transmitted and received underwater.

[0028] The transmitter / receiver unit 16 is composed of an all-around sonar, and the scan angle δ (azimuth angle, see Figure 3) and tilt angle θ (depression angle, see Figure 2) of the ultrasonic TB transmitted and received by the transmitter / receiver unit 16 can be changed.

[0029] The scan angle δ is the angle representing the transmission and reception direction of the ultrasonic TB when viewing the water surface on which the vessel 11 is floating from above. In this embodiment, when viewing the water surface from above, the scan angle δ is defined as 0 degrees when the ultrasonic TB is transmitted and received in the forward direction of the vessel 11 (the direction in which the vessel 11 moves forward, the bow direction), and the size of the scan angle δ is defined such that the scan angle δ increases as the transmission and reception direction of the ultrasonic TB changes clockwise around the vessel 11.

[0030] The tilt angle θ (depression angle) is the angle between the transmission and reception direction of the ultrasonic TB and the water surface (horizontal plane) on which the ship 11 floats. The angle is defined such that 0 degrees is defined when the ultrasonic TB is transmitted and received parallel to the water surface (horizontal plane), and the tilt angle θ increases as the transmission and reception direction of the ultrasonic TB moves away from the water surface (horizontal plane) and becomes perpendicular to the water surface.

[0031] The transmitting / receiving unit 16 transmits an ultrasonic TB while fixed in the direction of a predetermined tilt angle θ and scan angle δ. The transmitted ultrasonic TB is, for example, a short burst wave with a frequency of 240 kHz and a duration of 100 to 200 microseconds. Alternatively, instead of such a burst wave, or following the burst wave, a chirp wave may be used as the transmitted ultrasonic TB, for example, one whose frequency gradually changes from 130 kHz to 220 kHz over 5 milliseconds.

[0032] The transmitter / receiver unit 16 transmits ultrasonic waves TB in a predetermined direction with a tilt angle θ and scan angle δ. It then uses this direction as one of the predetermined directions and receives reflected ultrasonic waves TB from objects GF or the seabed present in that direction, thereby performing underwater detection in that predetermined direction. Once the underwater detection in the predetermined direction is complete, the transmitter / receiver unit 16 keeps the tilt angle θ fixed to the set value and uses a scan angle δ set, for example, clockwise (right-hand rotation), to transmit ultrasonic waves TB in a new predetermined direction and receives reflected ultrasonic waves TB in that direction. The ultrasonic sonar device 12 performs horizontal detection over a predetermined range set by the user (shown as the entire circumference in Figure 3) by sequentially rotating the transmission and reception of ultrasonic waves TB by the transmitter / receiver unit 16.

[0033] Here, with reference to Figure 4, the detailed configuration of the transmitter / receiver unit 16 will be described. The transmitter / receiver unit 16 consists of a bottomed cylindrical lower case 21 with an open upper end and a hemispherical lower end, a covered cylindrical upper case 22 with an open lower end and a disc-shaped upper end, and a disc-shaped lid 23 that closes the lower end opening of the upper case 22 and the upper end opening of the lower case 21. An upper storage space 24 is formed by the upper surface of the lid 23 and the upper case 22, and a lower storage space 25 is formed by the lower surface of the lid 23 and the lower case 21.

[0034] A through-hole 26 is formed in the center of the cover 23. A scan motor 27, which is composed of a stepping motor, is fixed to the center of the cover 23, and the output shaft 27a of the scan motor 27 extends straight down from the lower surface of the scan motor 27, rotatably inserted through the through-hole 26. The tip (lower end) of the output shaft 27a reaches the upper part of the lower storage space 25.

[0035] A disc-shaped support plate 28 is provided at the tip of the output shaft 27a, and the center of the upper surface of the support plate 28 is connected to the tip of the output shaft 27a. A support frame 29, which is roughly inverted U-shaped, is provided on the lower surface of the support plate 28, and a horizontally extending rotating shaft 30 is rotatably mounted between the lower ends of the support frame 29.

[0036] A transducer 31 is fixed to the center of the rotating shaft 30, which transmits a narrow beam-shaped ultrasonic wave TB (see Figure 2) in one direction and receives the reflected wave of the transmitted ultrasonic wave TB. A substantially semicircular tilt gear 32 is fixed to the rotating shaft 30 at a position adjacent to the transducer 31, and the rotating shaft 30, transducer 31, and tilt gear 32 are configured to rotate together as a single unit.

[0037] A tilt motor 33, which is composed of a stepping motor, is fixed to the upper end of the support frame 29. The tilt motor 33 has an output shaft 33a that extends toward the tilt gear 32. A small gear 33b is provided at the tip of the output shaft 33a, and the small gear 33b meshes with the tilt gear 32.

[0038] When the scan motor 27 is driven, the output shaft 27a rotates, and as a result, the support plate 28, the support frame 29, and the rotating shaft 30 rotate together around the output shaft 27a, causing the vibrator 31, which is fixed to the rotating shaft 30, to also rotate around the output shaft 27a.

[0039] This allows the direction of ultrasonic TB transmission by the transducer 31 to be changed clockwise or counterclockwise when viewed from above the water surface on which the ship 11 is floating. In other words, by driving the scan motor 27, the scan angle δ of the ultrasonic TB transmitted by the transducer 31 is changed.

[0040] On the other hand, when the tilt motor 33 is driven, the output shaft 33a rotates, and consequently the small gear 33b rotates, causing the tilt gear 32, which meshes with the small gear 33b, to rotate. As a result, the rotating shaft 30 to which the tilt gear 32 is fixed rotates in accordance with the rotation of the tilt gear 32, and the vibrator 31, which is fixed to the rotating shaft 30, rotates around the rotating shaft 30 as its axis.

[0041] As a result, the tilt angle θ, which is the angle between the direction the transducer 31 is facing (the transmission direction of the ultrasonic TB transmitted from the transducer 31) and the water surface on which the ship 11 is floating, is changed by driving the tilt motor 33.

[0042] Returning to Figures 1-3, we continue the explanation of the schematic configuration of the ultrasonic sonar device 12. The GPS antenna 18 is electrically connected to the main unit 13 by a cable. The GPS antenna 18 receives signals transmitted from multiple GPS satellites S, and these received signals are transmitted to the main unit 13. The main unit 13 is located, for example, in the wheelhouse of a ship 11. When it receives signals from multiple GPS satellites S via the GPS antenna 18, it acquires the position (latitude and longitude) of the ship 11 (its own vessel) and the direction the ship 11 is sailing at each unit of time based on these received signals.

[0043] The unit time is set to, for example, 1 second. Alternatively, the unit time may be set to be changeable by the user operating the operation button 14.

[0044] The display device 15 has a display area 15a made of a liquid crystal panel or an organic EL (Electro-Luminescence) panel, and a detection result image 81, which is the result of detection performed by the ultrasonic sonar device 12, is displayed in the display area 15a.

[0045] For example, when the ultrasonic sonar device 12 performs horizontal detection, the detection result image 81 is displayed in the display area 15a, showing the detection results in the water within a specific range centered on the vessel 11 projected onto a plane parallel to the horizontal plane. This detection result image 81 is represented as a circle (or a sector with the position of the vessel 11 as the central angle) centered on the vessel 11, and is generated based on the received signals for each predetermined direction, which are generated based on the reflected waves of the ultrasonic TB received by the transmitting / receiving unit 16, as will be described later.

[0046] The specific range in which the underwater detection results are displayed as detection result image 81 is defined by a plane parallel to the horizontal plane and is set by the user operating the operation button 14. That is, if the depth of the seabed is shallow or the tilt angle θ of the ultrasonic TB is large (ultrasonic TB is transmitted in a direction close to the vertical), the underwater detection will be performed in a narrow range when viewed from a plane parallel to the horizontal plane. Therefore, in this case, the user can grasp the detection results in detail by setting the specific range to a narrower range. On the other hand, if the depth of the seabed is deep or the tilt angle θ of the ultrasonic TB is small (ultrasonic TB is transmitted in a direction close to the horizontal), the underwater detection will be performed in a wide range when viewed from a plane parallel to the horizontal plane. Therefore, in this case, the user can grasp the detection results as comprehensively as possible by setting the specific range to a wider range.

[0047] Furthermore, the display device 15 displays the track 82 of the vessel 11 (own vessel) within a specific range displayed in the detection result image 81, with the track drawn on top of the detection result image 81. The track image used to draw the track 82 on the detection result image 81 is generated based on the longitude and latitude of the vessel 11 and the bearing of the vessel 11 for each unit time, which are acquired based on the signal received from the GPS antenna 18, as described later.

[0048] Here, when instructed by the user, the ultrasonic sonar device 12 adjusts the scale of the track 82 to match the bearing of the detection result image 81 for a predetermined time (for example, 10 seconds), while maintaining the specific range displayed in the detection result image 81, and changes the scale of the track 82 to a different scale from that of the detection result image 81, thereby generating a track image for drawing the track 82 on the detection result image 81. The period from the start of displaying the scaled track 82 until the predetermined time has elapsed corresponds to the predetermined period for displaying the scaled track 82.

[0049] Furthermore, the display of the track 82 may be configured to be set by the user. That is, if the user sets the ultrasonic sonar device 12 to display the track 82, the track 82 may be displayed in the detection result image 81, and if the user sets the ultrasonic sonar device 12 to not display the track 82, the track 82 may be hidden from the detection result image 81.

[0050] In addition to the detection result image 81 of the underwater detection and the track 82 of the vessel 11, the display area 15a may also display detection result images showing the detection results of underwater detection performed under other conditions (for example, fish detection mode or vertical cross-section detection mode). Furthermore, in addition to the detection result image 81, the display area 15a may also display information 83 indicating the conditions of horizontal detection shown in the detection result image 81 and information of the specific range shown in the detection result image 81, and information 84 indicating the scale of the track 82.

[0051] In the example shown in Figure 1, information 83 indicates that the tilt angle θ for horizontal detection shown in the detection result image 81 is set to 45 degrees, and that the range for the transmission and reception direction of the ultrasonic TB shown in the detection result image 81 is set to 80m, the horizontal range to 57m, and the vertical range to 57m. The horizontal range is information that indicates a specific range. Also, in the example shown in Figure 1, information 84 indicates that the scale of the track 82 is set to 10m.

[0052] The operation buttons 14 are buttons that can be operated by the user, for example, when the user turns the power on / off or makes various settings on the ultrasonic sonar device 12. Multiple operation buttons 14 are provided on the main unit 13, for example, below (or to the right of) the display device 15.

[0053] For example, when performing underwater detection using horizontal detection, the user can set the detection range (predetermined range), the tilt angle θ of the ultrasonic TB, the feed angle of the scan angle δ when transmitting while rotating the ultrasonic TB, the range (specific range) of the detection result image 81 showing the detection results of horizontal detection, and the modified scale setting data 52b (see Figure 5), which will be described later, using the operation button 14.

[0054] Furthermore, the ultrasonic sonar device 12 is equipped with a track scale change button 14a as one of its operation buttons 14. The track scale change button 14a is a button that allows the user to instruct the device to change the scale of the track 82 displayed on the detection result image 81 in the display area 15a to a different scale from that of the detection result image 81.

[0055] If the track scale change button 14a is operated by the user during the period when the track 82 is displayed on the detection result image 81 at the same scale as the detection result image 81, the scale of the track 82 is changed to the scale previously set by the user according to the change scale setting data 52b, and the track 82 is displayed on the detection result image 81. At this time, the specific range in which the detection result image 81 is displayed is maintained. The technical significance of changing the scale of the track 82 and displaying it will be explained later with reference to Figures 9 and 10. Note that the track scale change button 14a corresponds to the "instruction means" of the present invention.

[0056] Next, the electrical configuration of the ultrasonic sonar device 12 will be described with reference to Figure 5. Figure 5 is a block diagram showing the electrical configuration of the ultrasonic sonar device 12.

[0057] The main body 13 (see Figure 1) of the ultrasonic sonar device 12 has a control device 50. The control device 50 controls the operation of the ultrasonic sonar device 12. As shown in Figure 5, the control device 50 has a CPU (Central Processing Unit) 51, flash memory 52, and RAM (Random Access Memory) 53, which are connected to the input / output port 54 via a bus line 55.

[0058] The control device 50 also includes a motor driver 61, a transmit / receive circuit 62, a display controller 63, and a GPS interface 65 (hereinafter referred to as "GPS I / F65"), each of which is connected to the input / output port 54. The control device 50 also includes a video RAM 64 (hereinafter referred to as "VRAM64"). The VRAM64 is connected to the display controller 63.

[0059] The display device 15 is connected to the display controller 63. The GPS antenna 18 is connected to the input / output port 54 via the GPS I / F 65. The scan motor 27 and tilt motor 33 (see Figure 4) that constitute the transmitter / receiver unit 16 are connected to the input / output port 54 via the motor driver 61, and the transducer 31 (see Figure 4) that constitutes the transmitter / receiver unit 16 is connected to the input / output port 54 via the transmit / receive circuit 62. Furthermore, the operation buttons 14 and the lifting device 17 (see Figure 1) are connected to the input / output port 54 either directly or via interface circuits (not shown).

[0060] The CPU 51 is an arithmetic unit that performs various calculations to control the operation of the ultrasonic sonar device 12 according to the program data 52a stored in the flash memory 52. ​​For example, it performs the various processes shown in Figures 6 to 8. These processes will be described later with reference to Figures 6 to 8. In addition to these various processes, the CPU 51 also performs various controls to realize the various functions of the ultrasonic sonar device 12.

[0061] For example, when the CPU 51 determines from the signal input from the operation button 14 that the user has operated the operation button 14, it executes control corresponding to the operation of the operation button 14. If various setting values ​​are changed as a result of the operation of the operation button 14, the CPU 51 executes processes such as displaying a screen related to the setting change, accepting input of the changed setting value, and storing the changed setting value in the flash memory 52.

[0062] The flash memory 52 is a rewritable, non-volatile memory that stores program data 52a executed by the CPU 51, as well as various setting values ​​and fixed value data referenced by the CPU 51 when the program data 52a is executed. Note that the program data 52a and fixed value data may be stored in a separate, non-rewritable ROM (Read Only Memory) instead of the flash memory 52.

[0063] The flash memory 52 stores various setting values, such as the scale change setting data 52b and the horizontal detection tilt angle data 52c. As described above, these various setting values, including the scale change setting data 52b and the horizontal detection tilt angle data 52c, can be changed by the user by operating the operation button 14.

[0064] The scale change setting data 52b is a setting value for setting the new scale when the scale of the track 82 is changed and displayed. When the track scale change button 14a is operated by the user, the CPU 51 refers to the scale change setting data 52b. Then, the track 82 is drawn and displayed on the detection result image 81 at the scale indicated by the scale change setting data 52b, rather than at the same scale as the detection result image 81, for a predetermined time (for example, 10 seconds) until the track 82 is drawn and displayed. As described above, the specific range displayed on the detection result image 81 is maintained during this period. After the predetermined time has elapsed, the track 82 will be displayed on the detection result image 81 again at the same scale as the detection result image 81.

[0065] The scale change setting data 52b is pre-stored with a predetermined initial value (for example, 5km) at the time of shipment. On the other hand, the scale change setting data 52b and the operation button 14 for changing the setting value of the scale change setting data 52b allow the user to pre-set the scale of the track 82, which will be changed for a predetermined period of time. In other words, the scale change setting data 52b and the operation button 14 constitute the "scale setting acceptance means" of the present invention.

[0066] In this embodiment, the modified scale setting data 52b stores the setting value for the modified scale when the scale of the track 82 is changed and displayed. However, one or more setting values ​​for the modified scale when the scale of the track 82 is changed and displayed may be defined in the program data 52a. In this case, the setting value may be a fixed value that cannot be changed by the user.

[0067] On the other hand, the modified scale setting data 52b may store multiple set values ​​for the modified scale when the scale of the track 82 is changed and displayed.

[0068] If multiple scale settings are stored in the scale setting data 52b or defined in the program data 52a, then, during the period from when the display of the scaled track 82 begins until a predetermined time has elapsed (i.e., during the predetermined period), each time the user operates the track scale change button 14a (or another operation button 14), one of the multiple setting values ​​may be selected sequentially (in descending or ascending order) in a loop, and the track 82 may be displayed in the detection result image 81 at the scale indicated by the selected setting value. In this case, if the track scale change button 14a is operated while the track 82 is displayed at the same scale as the detection result image 81, the scale of the track 82 that was displayed at the end of the previous predetermined period may be selected first.

[0069] Furthermore, the changed scale setting value may be stored in the changed scale setting data 52b or defined in the program data 52a in a manner that corresponds to each value indicating the range of a specific area displayed by the detection result image 81, or to each scale value of the detection result image 81, or to each of the multiple ranges divided for these values. This makes it possible to set the scale of the track 82 displayed on the detection result image 81 when the track scale change button 14a is operated by the user, according to the width of the specific area displayed by the detection result image 81 or the scale of the detection result image 81 displayed on the display device 15 at that time.

[0070] The horizontal detection tilt angle data 52c is a setting value for setting the tilt angle θ of the transmission direction of the ultrasonic TB transmitted when performing horizontal detection. In the horizontal detection tilt angle data 52c, the closer the tilt angle θ is set to 0 degrees, the wider the underwater detection area becomes, and the closer the tilt angle θ is set to 90 degrees, the narrower the underwater detection area directly beneath the vessel 11 becomes.

[0071] In addition to the above, the various setting values ​​stored in the flash memory 52 include settings for when performing underwater detection by horizontal detection, such as the detection range (predetermined range), the tilt angle θ of the ultrasonic TB, the feed angle of the scan angle δ when transmitting while rotating the ultrasonic TB, and the range (specific range) of the detection result image 81 that shows the detection results of horizontal detection.

[0072] The setting value for determining the horizontal detection range (predetermined range) is set by the scan angle δ of the ultrasonic TB. For example, if the predetermined range is set to 45 degrees to 135 degrees, the transmission direction of the ultrasonic TB is rotated within the scan angle δ range of 45 degrees to 135 degrees, thereby performing underwater detection within that range. If the predetermined range is set to 0 degrees to 0 degrees, the transmission direction of the ultrasonic TB is rotated within the entire scan angle δ range. In other words, the ultrasonic TB is transmitted while rotating around the entire circumference. As a result, underwater detection is performed around the entire circumference centered on the ship 11 (or its transmitting / receiving unit 16).

[0073] RAM 53 is a rewritable, volatile memory that temporarily stores various data when the CPU 51 executes a program. RAM 53 stores, for example, tilt angle data 53a, scan angle data 53b, and a track scale change flag 53c.

[0074] Tilt angle data 53a is data indicating the tilt angle θ of the ultrasonic TB transmission direction. Scan angle data 53b is data indicating the next scan angle δ that the ultrasonic TB should face in the transmission and reception direction. When horizontal detection is started at the timing when the ultrasonic sonar device 12 is powered on or when underwater detection is started, the tilt angle data 53a is initially set to the tilt angle θ set in the horizontal detection tilt angle data 52c. At this time, the scan angle data 53b is initially set to the starting angle of the predetermined range for horizontal detection stored in the flash memory 52.

[0075] While horizontal detection is being performed, the orientation of the transducer 31 is changed by the scan motor 27, and the CPU 51 updates the scan angle data 53b so that the transducer 31 should next face the scan angle δ. Based on the updated scan angle data 53b, the CPU 51 controls the scan motor 27 via the motor driver 61. This allows the transducer 31 to be oriented in the direction in which ultrasonic TB should be transmitted or in the direction in which reflected waves should be received.

[0076] Furthermore, the tilt angle data 53a is changed to the new setting value of the horizontal detection tilt angle data 52c only when the user changes the setting value of the horizontal detection tilt angle data 52c by operating the operation button 14; otherwise, the value is maintained. When the value of the tilt angle data 53a is changed, the tilt motor 33 is driven via the motor driver 61 under the control of the CPU 51 so that the tilt angle θ of the ultrasonic TB transmission direction becomes the tilt angle θ indicated by the changed tilt angle data 53a.

[0077] When the scan motor 27 is driven and the scan angle δ in the transmission and reception direction of the ultrasonic TB becomes the scan angle δ indicated by the scan angle data 53b (if the tilt angle θ is changed, in addition to the scan angle δ, the tilt motor 33 is also driven and the tilt angle θ in the transmission direction of the ultrasonic TB becomes the tilt angle θ indicated by the tilt angle data 53a), the CPU 51 controls the transducer 31 to transmit the ultrasonic TB and the transducer 31 to receive the reflected waves of the ultrasonic TB.

[0078] The track scale change flag 53c is a flag that indicates a change in the scale of the track 82. When the track scale change flag 53c is set to "1", it indicates that the scale of the track 82 will be changed to a different scale from the scale of the detection result image 81, and when it is set to "0", it indicates that the scale of the track 82 will not be changed to a different scale from the scale of the detection result image 81, that is, the scale of the track 82 will be the same as the scale of the detection result image 81.

[0079] The track scale change flag 53c is initialized to "0" when the ultrasonic sonar device 12 is powered on or when underwater detection begins. When the user operates the track scale change button 14a, the track scale change flag 53c is set to "1". In conjunction with this, the CPU 51 starts a timer (not shown) provided in the control device 50 and counts the elapsed time (for example, 10 seconds). When the predetermined time has elapsed, the track scale change flag 53c is set to "0".

[0080] When the track scale change flag 53c is "1", the CPU 51 controls the generation of a track image for drawing the track 82 at a different scale than the detection result image 81, and composites the track image of the track 82, drawn at a different scale than the detection result image 81, with the detection result image 81, whose display range is maintained within a specific range. On the other hand, when the track scale change flag 53c is "0", the CPU 51 controls the generation of a track image for drawing the track 82 at the same scale as the detection result image 81, and composites that track image with the detection result image 81.

[0081] As a result, for a predetermined period of time after the user operates the track scale change button 14a, the track 82, drawn at a different scale than the detection result image 81, is displayed on the detection result image 81, while maintaining the display range within a specific range.

[0082] The motor driver 61 is a driver that drives the scan motor 27 and tilt motor 33 of the transmitting / receiving unit 16 under control from the CPU 51. When the CPU 51 specifies a tilt angle θ stored in the tilt angle data 53a, the motor driver 61 drives the tilt motor 33 so that the tilt angle θ in the transmission direction of the ultrasonic TB becomes the specified tilt angle θ. Also, when the CPU 51 specifies a scan angle δ stored in the scan angle data 53b, the motor driver 61 drives the scan motor 27 so that the scan angle δ in the transmission direction of the ultrasonic TB becomes the specified scan angle δ.

[0083] As a result, the transducer 31 is rotated by the scan motor 27 and the tilt motor 33. Therefore, ultrasonic waves TB are transmitted from the transducer 31 in the direction of the tilt angle θ stored in the tilt angle data 53a and the scan angle δ stored in the scan angle data 53b, and the reflected waves of ultrasonic waves TB reflected in that direction can be received by the transducer 31.

[0084] The transmitting and receiving circuit 62 is a circuit that includes a transmitting circuit for generating a drive voltage to drive the transducer 31 and generate ultrasonic TB, and for applying the drive voltage to the transducer 31, and a receiving circuit for receiving the voltage generated by the transducer 31 when the transducer 31 receives the reflected wave of ultrasonic TB, and for generating a received signal from that voltage.

[0085] The transmitting circuit of the transmitting / receiving circuit 62 applies a drive voltage to the transducer 31 so that it generates ultrasonic TB, such as burst waves or chirp waves as described above, based on control from the CPU 51. The transducer 31 generates ultrasonic TB according to this drive voltage and transmits the ultrasonic TB in the direction of the tilt angle θ and scan angle δ rotated by the scan motor 27 and the tilt motor 33.

[0086] Furthermore, the receiving circuit of the transmitting / receiving circuit 62 includes an amplification circuit and an analog-to-digital conversion circuit (AD conversion circuit). The receiving circuit amplifies the voltage generated when the transducer 31 receives the reflected wave of the ultrasonic TB using the amplification circuit, and then converts it into a digital signal (digital value) using the AD conversion circuit. The receiving circuit transmits this digital signal as the received signal to the CPU 51.

[0087] The GPS I / F 65 acquires the latitude and longitude of the vessel 11 (the ship itself) and the direction of its navigation at each unit time based on signals received from multiple GPS satellites S received by the GPS antenna 18, and inputs these as position information to the CPU 51. The GPS antenna 18 and the GPS I / F 65 constitute the "acquisition means" of this invention.

[0088] The display controller 63 corresponds to the "display control means" of the present invention, and based on the control of the CPU 51, generates various images to be displayed on the display device 15, and combines these images to display the combined image on the display device 15.

[0089] VRAM64 is a memory for storing image data of various images generated by the display controller 63, and images created by combining various images to be displayed on the display device 15. For example, detection result image data 64a and track image data 64b are stored in VRAM64.

[0090] The detection result image data 64a is data representing the detection result image 81 generated by the display controller 63 based on the control of the CPU 51. The detection result image 81 is a circular image (or a sector with the position of the ship 11 as the central angle) centered on the position of the ship 11, in which the intensity of the reflected ultrasonic TB waves reflected from each position within a specific range pre-set by the user is projected onto a plane parallel to the horizontal plane, and each position is represented by a color corresponding to the intensity.

[0091] The display controller 63 uses the received signals for each predetermined direction, generated by the transmitting / receiving circuit 62 when the transducer 31 receives reflected ultrasonic TB waves in each predetermined direction, to perform filtering and pixel interpolation on these received signals. This allows the display controller 63 to calculate the intensity of the reflected ultrasonic TB waves from the position corresponding to each pixel in the detection result image 81. The display controller 63 then assigns a color to each pixel of the detection result image 81 corresponding to the calculated intensity of the reflected ultrasonic TB waves at that pixel. The display controller 63 stores the color information assigned to each pixel of the detection result image 81 in the detection result image data 64a.

[0092] The track image data 64b is data representing a track image, generated by the display controller 63 based on the control of the CPU 51. The track image is an image for plotting the track 82 of the vessel 11 on the detection result image 81. The display controller 63 generates a track image showing the track 82 to be plotted on the detection result image 81 based on the position information of the vessel 11 (latitude and longitude of the vessel 11, and the direction in which the vessel 11 is sailing) acquired every unit time by the GPS I / F 65 using signals received from GPS satellites S by the GPS antenna 18.

[0093] In this case, if the track scale change flag 53c is "0", the CPU 51 instructs the display controller 63 to draw the track 82 at the same scale as the detection result image 81. As a result, the display controller 63 generates a track image such that the track 82 of the ship 11 within the specific range indicated by the detection result image 81 is drawn on the detection result image 81 at the same scale as the detection result image 81.

[0094] On the other hand, if the track scale change flag 53c is "1", the CPU 51 instructs the display controller 63 to draw the track 82 at a different scale than the detection result image 81, that is, at the scale set in the change scale setting data 52b. As a result, the display controller 63 generates a track image such that the track 82 is drawn relative to the detection result image 81 at a different scale than the detection result image 81, that is, at the scale indicated in the change scale setting data 52b, while aligning with the bearing indicated by the detection result image 81.

[0095] The display controller 63 generates various images, including information 83 and information 84, to be displayed in the display area 15a of the display device 15. The display controller 63 then combines various images, including track image data 64b, with the detection result image data 64a, and displays the combined image in the display area 15a of the display device 15.

[0096] In this embodiment, the case in which the display controller 63 generates the detection result image 81 and the track image based on control from the CPU 51 has been described. However, the CPU 51 may generate part or all of the detection result image 81, the track image, and other images based on the program data 52a. Furthermore, the CPU 51 may also perform the synthesis of these images based on the program data 52a.

[0097] Next, referring to Figures 6 to 8, the main processes executed by the CPU 51 to realize horizontal detection by the ultrasonic sonar device 12 will be described. Here, it is assumed that the predetermined range setting for horizontal detection is set to 0 to 360 degrees, i.e., the entire circumference. Also, for the sake of clarity, the process shown in Figures 6 to 8 will be described in parallel by the CPU 51. However, while the CPU 51 is executing the loop processing as the main process, all or part of the processes described in Figures 6 to 8 may be executed according to the state at that time.

[0098] Figure 6 is a flowchart showing the horizontal detection process executed by the CPU 51. The horizontal detection process is the process for performing horizontal detection with the ultrasonic sonar device 12, and is started by the CPU 51 when the power is turned on or when horizontal detection is started by the user operating the operation button 14. This horizontal detection process continues to run until horizontal detection is terminated by the user operating the operation button 14 or the like.

[0099] When the CPU 51 starts the horizontal detection process, it first drives the lifting device 17 to lower the transmitter / receiver unit 16 (S1). This causes the transmitter / receiver unit 16 to protrude from the bottom of the ship 11 into the water, enabling the transducer 31 to transmit and receive ultrasonic TB. If the ultrasonic sonar device 12 does not have a lifting device 17 and the transmitter / receiver unit 16 is fixed in a position where it can transmit and receive ultrasonic TB to and from the water of the ship 11, then the process in S1 is omitted.

[0100] Next, the CPU 51 updates the tilt angle data 53a to the tilt angle θ set in the horizontal detection tilt angle data 52c (S2). As a result, the processing in S4, described later, can determine the direction of transmission of ultrasonic TB by the transducer 31 and the reception of the reflected waves of the ultrasonic TB to the direction of the tilt angle θ indicated by the horizontal detection tilt angle data 52c set in the tilt angle data 53a.

[0101] Next, the CPU 51 initializes the scan angle data 53b to the starting angle of a predetermined range of horizontal detection (for example, 0°) (S3). This allows the scan angle δ in the direction in which the transducer 31 transmits ultrasonic waves TB and receives the reflected waves of those ultrasonic waves TB to be first set to the initial value (for example, 0°) set in the scan angle data 53b, through the processing in S4 described later.

[0102] Next, the CPU 51 transmits the tilt angle θ indicated by the tilt angle data 53a and the scan angle δ indicated by the scan angle data 53b to the motor driver 61, causing the motor driver 61 to drive the tilt motor 33 to the tilt angle θ and the scan motor 27 to the scan angle δ (S4). As a result, the transducer 31 is rotated, and the transmission direction of the ultrasonic TB and the reception direction of the reflected waves of the ultrasonic TB are set to the tilt angle θ indicated by the tilt angle data 53a and the scan angle δ indicated by the scan angle data 53b.

[0103] Next, the CPU 51 instructs the transmitting / receiving circuit 62 to transmit ultrasonic TB from the transducer 31, which is set in the direction of the tilt angle θ indicated by the tilt angle data 53a and the scan angle δ indicated by the scan angle data 53b, as processed in S4 (S5). As a result, the transmitting / receiving circuit 62 drives the transducer 31, and ultrasonic TB is transmitted from the transducer 31 in the direction of the tilt angle θ and scan angle δ set in the processing of S4.

[0104] After transmitting an ultrasonic wave TB, the transducer 31 receives the reflected ultrasonic wave TB reflected from the object to be detected GF or the seabed in the direction of transmission, and outputs a voltage based on the received intensity. When the transmitting / receiving circuit 62 receives the voltage output from the transducer 31, it amplifies the voltage using its amplification circuit, converts it to a digital value using its AD conversion circuit, and transmits this digital value to the CPU 51 as a received signal in the predetermined direction from which the ultrasonic wave TB was transmitted and received.

[0105] The CPU 51 receives the received signal transmitted from the transmitting / receiving circuit 62 as a received signal for the direction of reception of the reflected ultrasonic TB wave set by the processing in S4 (S6). The CPU 51 stores the received signal in RAM 53 for each direction of reception of the reflected ultrasonic TB wave (for each predetermined direction).

[0106] Next, the CPU 51 instructs the display controller 63 to generate a detection result image 81 based on the received signals stored in the RAM 53 for each direction of reception of the reflected ultrasonic TB waves (for each predetermined direction) (S7). The display controller 63 then uses the received signals for each predetermined direction stored in the RAM 53 to perform filtering and pixel interpolation on these signals, calculates the intensity of the reflected ultrasonic TB waves from the position corresponding to each pixel in the detection result image 81, and assigns a color corresponding to the calculated intensity of the reflected ultrasonic TB waves to each pixel, thereby generating the detection result image 81. The detection result image data 64a representing the generated detection result image 81 is stored in the VRAM 64. This detection result image 81 is combined with other images by a display control process described later and then displayed in the display area 15a of the display device 15. Note that this S7 process corresponds to the "detection result image generation means" of the present invention.

[0107] Next, the CPU 51 determines whether the termination conditions for horizontal detection are met (S8). Examples of termination conditions for horizontal detection include the operation of a predetermined operation button 14 by the user. If the CPU 51 determines, as a result of the determination in S8, that the termination conditions are met (S8:Yes), it terminates the horizontal detection process.

[0108] On the other hand, if the CPU 51 determines, as a result of the judgment in S8, that the termination conditions are not met (S8: No), it then determines whether the tilt angle θ setting has been changed (S9). The CPU 51 determines that the tilt angle θ setting has been changed if the setting value of the horizontal detection tilt angle data 52c is changed by the operation of the user's operation button 14.

[0109] If the CPU 51 determines, as a result of the judgment in S9, that there has been no change in the tilt angle θ setting (S9: No), it updates the scan angle data 53b (S10). Specifically, the CPU 51 adds a predetermined feed angle to the scan angle δ shown in the scan angle data 53b. If the scan angle δ shown in the scan angle data 53b after the addition is 360° or more, 360° is subtracted from the scan angle δ shown in the scan angle data 53b after the addition. After updating the scan angle data 53b, the CPU 51 returns to processing S4.

[0110] As a result, the ultrasonic sonar device 12 transmits and receives ultrasonic TB in one predetermined direction, then rotates the transducer 31 by a preset feed angle while maintaining the tilt angle θ, and transmits and receives ultrasonic TB in that new predetermined direction. The ultrasonic sonar device 12 then repeatedly performs horizontal detection over a predetermined range (in this case, the entire circumference) by transmitting and receiving ultrasonic TB in that predetermined direction while changing the predetermined direction by the feed angle in the scan direction.

[0111] Furthermore, if the CPU 51 determines, as a result of the judgment in S9, that the setting of the tilt angle θ has been changed (S9: Yes), it instructs the display controller 63 to erase the detection result image data 64a and clear the detection result image 81 (S11), and then proceeds to the processing in S2. As a result, the tilt angle data 53a is updated with the tilt angle θ newly set by the user for the horizontal detection tilt angle data 52c, the scan angle data 53b is initialized to its initial value (for example, 0°), and horizontal detection is started with the new tilt angle θ.

[0112] Next, with reference to Figure 7, the track generation process executed by the CPU 51 will be explained. Figure 7 is a flowchart of the track generation process. The track generation process is the process of generating a track image for drawing a track 82 on the detection result image 81 when horizontal detection is performed by the ultrasonic sonar device 12. The track generation process is started by the CPU 51 when the power is turned on or when horizontal detection is started by the user operating the operation button 14, and is processed in parallel with the horizontal detection process. This track generation process continues to run until horizontal detection is terminated by the user operating the operation button 14, etc.

[0113] Furthermore, if the user sets whether to display or hide the track 82, the track generation process will only be executed if the user has set the track 82 to be displayed. If the user sets the track 82 to be hidden while the track generation process is running, the CPU 51 will terminate the track generation process.

[0114] When the CPU 51 starts executing the track generation process, it first obtains the position information of the vessel 11, including the latitude and longitude of the vessel 11 at that time, and the bearing in which the vessel 11 is sailing, from the GPS I / F 65 (S21). This S21 process corresponds to the "acquisition means" of the present invention. The CPU 51 obtains the current time from an RTC (real-time clock) (not shown) provided in the control device 50, and then adds time information indicating the current time to the position information obtained in the S21 process, and adds it to the RAM 53 as position data and stores it (S22).

[0115] The RAM 53 is configured to store, for example, 86,400 location data points. That is, if the location information of the ship 11 is acquired every second, the RAM 53 is configured to store a day's worth of location information as location data. When the CPU 51 acquires new location information while 86,400 location data points are already stored in the RAM 53, the location data corresponding to the oldest timestamp among the location data stored in the RAM 53 is deleted, and the location data of the newly acquired location information is stored in the RAM 53 instead.

[0116] Next, the CPU 51 determines whether the track scale change flag 53c is "1" (S23). If, as a result of the determination in S23, the CPU 51 determines that the track scale change flag 53c is "0" and not "1" (S23: No), then it determines whether the track scale change button 14a has been operated by the user (S24).

[0117] If, as a result of the determination in S24, the CPU 51 determines that the track scale change button 14a has not been operated by the user (S24: No), it instructs the display controller 63 to generate a track image for drawing the track 82 on the detection result image 81 based on the position data stored in RAM 53 (S31). This process in S31 corresponds to the "track image generation means" of the present invention.

[0118] At this time, the track scale change flag 53c remains "0", and the scale of the track 82 is set to be the same as the scale of the detection result image 81. Therefore, the CPU 51 instructs the display controller 63 to draw the track 82 at the same scale as the detection result image 81. As a result, the display controller 63 generates a track image so that the track 82 of the ship 11 within the specific range indicated by the detection result image 81 is drawn on the detection result image 81 at the same scale as the detection result image 81. The generated track image is stored in VRAM as track image data 64b.

[0119] On the other hand, if the CPU 51 determines, as a result of the judgment in S24, that the track scale change button 14a has been operated by the user (S24: Yes), it sets the track scale change flag 53c to "1" (S25) and sets the scale of the track 82 to the scale set by the user with respect to the change scale setting data 52b (S26). Then, the CPU 51 starts a timer (not shown) provided in the control device 50 and starts measuring a predetermined time (for example, 10 seconds) (S27).

[0120] This predetermined time may be set to a fixed value in the program data 52a beforehand, or it may be set to be changeable by the user operating the operation button 14.

[0121] Then, the CPU 51 instructs the display controller 63 to generate a track image for drawing the track 82 on the detection result image 81, based on the position data stored in the RAM 53 (S31). At this time, through the processing in S25 and S26, the track scale change flag 53c is set to "1", and the scale of the track 82 is set to a different scale from the scale of the detection result image 81, that is, to the scale indicated by the change scale setting data 52b.

[0122] Therefore, the CPU 51 instructs the display controller 63 to draw the track 82 at a different scale than the detection result image 81, that is, at the scale indicated by the modified scale setting data 52b. As a result, the display controller 63 generates a track image so that the track 82 is drawn on the detection result image 81 at a different scale than the detection result image 81, that is, at the scale indicated by the modified scale setting data 52b, while matching the bearing indicated by the detection result image 81. The generated track image is stored in VRAM as track image data 64b.

[0123] Furthermore, if the CPU 51 determines, as a result of the judgment in S23, that the track scale change flag 53c is "1" (S23: Yes), then the CPU 51 determines, using the timer started by the process in S27, whether a predetermined time has elapsed (S28). If the CPU 51 determines, as a result, that the predetermined time has not elapsed (S28: No), it instructs the display controller 63 to generate a track image for drawing the track 82 on the detection result image 81, based on the position data stored in RAM 53 (S31).

[0124] At this time, the track scale change flag 53c remains "1", and the scale of the track 82 is set to a different scale from the scale of the detection result image 81, i.e., to the scale indicated by the change scale setting data 52b. Therefore, the CPU 51 instructs the display controller 63 to draw the track 82 at a different scale from the detection result image 81, i.e., to the scale indicated by the change scale setting data 52b. As a result, the display controller 63 generates a track image so that the track 82 is drawn relative to the detection result image 81 at a different scale from the scale of the detection result image 81, i.e., to the scale indicated by the change scale setting data 52b, while matching the bearing indicated by the detection result image 81. The generated track image is stored in VRAM as track image data 64b.

[0125] On the other hand, if the CPU 51 determines, as a result of the judgment in S28, that a predetermined time has elapsed (S28: Yes), it sets the track scale change flag 53c to "0" (S29) and sets the scale of the track 82 to be the same as the scale of the detection result image 81 (S30). Then, it instructs the display controller 63 to generate a track image for drawing the track 82 on the detection result image 81 based on the position data stored in RAM 53 (S31).

[0126] At this time, the processes in S29 and S30 set the track scale change flag 53c to "0", so that the scale of the track 82 is the same as the scale of the detection result image 81. Therefore, the CPU 51 instructs the display controller 63 to draw the track 82 at the same scale as the detection result image 81. As a result, the display controller 63 generates a track image so that the track 82 of the ship 11 within the specific range indicated by the detection result image 81 is drawn on the detection result image 81 at the same scale as the detection result image 81. The generated track image is stored in VRAM as track image data 64b.

[0127] After processing in S31, CPU 51 determines whether a unit of time (e.g., 1 second) has elapsed since obtaining the position information of the ship 11 through processing in S21 (S32). If CPU 51 determines that the unit of time has not elapsed (S32: No), it returns to processing in S23 and repeatedly executes the processing for generating the track image (processing in S23 to S31).

[0128] Furthermore, if the CPU 51 determines, as a result of the judgment in S32, that a unit of time has elapsed (S32: Yes), it returns to the process in S21, acquires new position information for the ship 11 (S21), adds it to the RAM 53 as position data and stores it (S22), and then executes the process for generating the track image (processing in S23 to S31).

[0129] The CPU 51, by executing this track generation process, normally generates a track image such that the track 82 of the vessel 11 within the specific range indicated by the detection result image 81 is drawn on the detection result image 81 at the same scale as the detection result image 81. On the other hand, if the track scale change button 14a is operated by the user, the CPU 51 generates a track image such that, for a predetermined time, the track 82 is drawn on the detection result image 81 at a different scale than the detection result image 81, i.e., at the scale indicated by the change scale setting data 52b, while still matching the bearing indicated by the detection result image 81. As a result, for a predetermined time after the user operates the track scale change button 14a, the detection result image 81 displays a track 82 with a different scale.

[0130] Next, with reference to Figure 8, the display control process executed by the CPU 51 will be described. Figure 8 is a flowchart of the display control process. The display control process is the process of synthesizing various images, including the detection result image 81, and displaying the resulting image in the display area 15a of the display device 15. The display control process is started by the CPU 51 when the power is turned on, or when horizontal detection is started by the user operating the operation button 14, and is processed in parallel with the horizontal detection process. This display control process continues to be executed until horizontal detection is terminated by the user operating the operation button 14, etc.

[0131] When the CPU 51 starts executing the display control process, it instructs the display controller 63 to combine the track image with the detection result image 81 and draw the track 82 (S41). Based on this instruction, the display controller 63 uses the detection result image data 64a and the track image data 64b stored in the VRAM to perform the process of combining the track image with the detection result image 81. This generates the detection result image 81 with the track 82 drawn on it. The image data representing this detection result image 81 with the track 82 drawn on it is stored in the VRAM 64.

[0132] Next, the CPU 51 instructs the display controller 63 to composite other images and characters, including information 83 and information 84, onto the detection result image 81 on which the track 82 is drawn (S42). Based on this instruction, the display controller 63 overwrites the image data showing the detection result image 81 on which the track 82 is drawn with other images and characters, including information 83 and information 84, thereby generating a detection result image 81 on which the track 82, information 83, information 84, and other information are composited.

[0133] Next, the CPU 51 determines whether the update time (for example, 33.3 milliseconds) for the image to be displayed on the display device 15 has elapsed (S43). If it is determined that the update time for the image to be displayed on the display device 15 has not elapsed (S43: No), the CPU 51 repeatedly performs the determination in S43.

[0134] Then, if the S43 decision determines that the update time for the image to be displayed on the display device 15 has elapsed (S43: Yes), the CPU 51 exits the S43 decision and, through the processing in S42, instructs the display controller 63 to display the detection result image 81, which is a composite of the track 82, information 83, information 84, and other information, in the display area 15a of the display device 15 (S44). As a result, the detection result image 81 is updated each time the update time elapses and displayed in the display area 15a of the display device 15.

[0135] After processing in S44, the CPU 51 returns to processing in S41 and S42, and then generates a detection result image 81 which is a composite of the track 82 to be displayed in the display area 15a, as well as information 83, information 84, and other information.

[0136] Next, referring to Figures 9 and 10, when the ultrasonic sonar device 12 displays the ship's (own ship's) track 82 along with the detection result image 81 of horizontal detection, under normal circumstances, the ship's track 82 within a specific range displayed by the detection result image 81 is drawn on the detection result image 81 at the same scale as the detection result image 81. However, for a predetermined period, the ship's track 82 is drawn on the detection result image 81 at a different scale than the detection result image 81. The technical significance of this will be explained.

[0137] First, Figure 9(a) is a diagram showing the track 82 of the vessel 11 on the detection result image 81 at the same scale as the detection result image 81, as measured by the ultrasonic sonar device 12. Figure 9(b) is a diagram showing the track 82a on the detection result image 81 at a smaller scale than the detection result image 81, as measured by the ultrasonic sonar device 12.

[0138] As described above, when the ultrasonic sonar device 12 displays the ship's (own ship's) track 82 along with the detection result image 81 of horizontal detection, it normally draws the ship's track 82 within the specific range displayed by the detection result image 81 on the detection result image 81, as shown in Figure 9(a). In this case, naturally, the scale of the track 82 is the same as the scale of the detection result image 81. This allows the user to steer the ship 11 by comparing the direction and distance where the reaction of the detected object GF shown in the detection result image 81 appeared with the ship's movement up to that point, based on the track 82 of the ship 11 within the specific range displayed by the detection result image 81, which is drawn at the same scale as the detection result image 81.

[0139] However, if the depth of the seabed in the predetermined range where horizontal detection is performed is shallow, or if the tilt angle θ of the ultrasonic TB transmission and reception direction is increased to transmit and receive the ultrasonic TB in a direction closer to the vertical, the specific range displayed in the detection result image 81 becomes narrower. Therefore, in this case, even if the track 82 of the vessel 11 is displayed in the detection result image 81 as shown in Figure 9(a), the track 82 is only displayed in a range close to the current position of the vessel 11, making it difficult to understand what kind of track the vessel 11 had followed before the detection result image 81.

[0140] In particular, if the vessel 11 was navigating while tracking the response of the detected object GF displayed in the detection result image 81, knowing the direction from which the vessel 11 was navigating relative to the currently displayed detection result image 81 would allow for inference of the direction in which the detected object GF response occurred in the past. Furthermore, while operating the vessel 11, there are many situations where it would be desirable to know the direction in which the detected object GF response occurred in the past. However, even if the track 82 is drawn on the detection result image 81, which has a narrow display range, if the track 82 is only displayed in a range close to the current position of the vessel 11, there is a problem in that it is difficult to infer the direction in which the detected object GF response occurred in the past.

[0141] In contrast, the ultrasonic sonar device 12 is configured to draw the ship's track 82 on the detection result image 81 at a different scale than the detection result image 81, while aligning the track 82 of the ship 11 with the direction of the detection result image 81 for a predetermined period of time.

[0142] For example, if the ultrasonic sonar device 12 plots the track 82a on the detection result image 81 at a smaller scale than the detection result image 81, as shown in Figure 9(b), the track 82a of the vessel 11 in a wider area than the specific range displayed on the detection result image 81 will be plotted on the detection result image 81. This allows the user to see the track 82a of the vessel 11 in areas outside the specific range, which could not be seen from the track 82 displayed according to the scale of the detection result image 81. Therefore, it is possible to understand what kind of track 82a the vessel 11 followed before the track 82 that is normally displayed on the detection result image 81. In addition, the user can infer in which direction there was a reaction from the detected object GF in the past.

[0143] Next, Figure 10(a) is a diagram showing the track 82 of the ship 11 on the detection result image 81 at the same scale as the detection result image 81, as measured by the ultrasonic sonar device 12, and Figure 10(b) is a diagram showing the track 82b on the detection result image 81 at a larger scale than the detection result image 81, as measured by the ultrasonic sonar device 12.

[0144] Under normal circumstances, as shown in Figure 10(a), the track 82 of the vessel 11 within a specific range displayed by the detection result image 81 is plotted on the detection result image 81. Using the detection result image 81 shown in Figure 10(a), as described above with reference to Figure 9(a), it is possible to consider the maneuvering of the vessel 11 by comparing the direction and distance at which the reaction of the detected object GF shown in the detection result image 81 appeared with the vessel 11's past movements on the detection result image 81.

[0145] However, if the depth of the seabed in the predetermined range where horizontal detection is performed is deep, or if the tilt angle θ of the ultrasonic TB transmission and reception direction is reduced to transmit and receive the ultrasonic TB in a direction closer to horizontal, the specific range displayed in the detection result image 81 will widen. In this case, although the user can grasp the track 82 of the vessel 11 over that wide range, there is a problem in that it is difficult to grasp the fine movements of the vessel 11 in the immediate vicinity and it is difficult to consider the effects of tides and wind on the movements of the vessel 11 in the immediate vicinity.

[0146] In contrast, when the ultrasonic sonar device 12 plots the track 82b on the detection result image 81 at a larger scale than the detection result image 81 for a predetermined period, as shown in Figure 10(b), the track 82b of the vessel 11 in a narrower range than the specific range displayed in the detection result image 81 is plotted on the detection result image 81. This allows the user to grasp the fine details of the vessel 11's recent movements, which could not be grasped from the track 82 displayed at the scale of the detection result image 81. Therefore, the user can steer the vessel 11 while considering the effects of tides and wind on the vessel 11's recent movements.

[0147] Based on the above, the ultrasonic sonar device 12, in conjunction with the detection result image 81, makes it easier to understand the movement of the ship 11 up to that point.

[0148] Furthermore, as shown in Figures 9(b) and 10(b), even when the track 82 is drawn on the detection result image 81 at a different scale than the detection result image 81 for a predetermined period, the detection result image 81 will display the same specific range as under normal circumstances. If the scale (display range) of the detection result image 81 were changed to match the scale of the modified track 82, there is a risk that the range the user wants to check in the detection result image 81 may be displayed too small, or conversely, the range the user wants to check may not be displayed at all. Even when the track 82 is drawn on the detection result image 81 at a different scale than the detection result image 81, the detection result image 81 will display the same specific range as under normal circumstances, ensuring that the detection results in the specific range are conveyed to the user comprehensively and clearly.

[0149] As described above, the ultrasonic sonar device 12, which is one embodiment of the present invention, provides the following effects.

[0150] (1) A transmitter / receiver unit 16 attached to the vessel 11 transmits ultrasonic TB over a predetermined range in the water set in all directions or in some directions from the vessel 11, and the reflected waves of ultrasonic TB reflected by the object to be detected GF, the seabed, etc., from each position in the water for each predetermined direction are received. Based on the reflected waves of ultrasonic TB received by the transmitter / receiver unit 16, a reception signal is generated for each predetermined direction, and based on the reception signal, a detection result image 81 is generated which shows the detection results in the water within a specific range from the vessel 11 projected onto a plane parallel to the horizontal plane. Meanwhile, the position information of the vessel 11 is acquired at unit time intervals. Based on the acquired position information of the vessel 11, a track image is generated for drawing the track 82 of the vessel 11 within the specific range shown in the detection result image 81 onto the detection result image 81. The detection result image 81 with the track 82 drawn on it is then displayed in the display area 15a of the display device 15 under the control of the display controller 63. This allows the user to compare the direction and distance at which the detected object GF showed up in the detection result image 81 with the ship's movement up to that point, based on the track 82 drawn on the detection result image 81.

[0151] (2) A track image is generated for a predetermined period of time in which the track 82 is aligned with the bearing of the detection result image 81, but drawn on the detection result image 81 at a different scale than the detection result image 81. As a result, for that predetermined time, the display area 15a of the display device 15 displays the track 82, which is drawn on the detection result image 81 at a different scale than the detection result image 81. Therefore, if the scale of the track 82 is smaller than the scale of the detection result image 81 for a predetermined period of time, the user can confirm the track 82a of the vessel 11 in an area outside a specific range that could not be grasped with the track 82 displayed at the scale of the detection result image 81. Also, if the scale of the track 82 is larger than the scale of the detection result image 81 for a predetermined period of time, the user can confirm the recent detailed movements of the vessel 11 that could not be grasped with the track 82 displayed at the scale of the detection result image 81. Therefore, the ultrasonic sonar device 12, in conjunction with the detection result image 81, makes it easier to understand the movement of the ship 11 up to that point.

[0152] (3) The user has previously set the scale of the track 82 in the track image that is generated only for a predetermined period. As a result, the ultrasonic sonar device 12 can display the track 82 at the desired scale set by the user on the detection result image 81 for a predetermined period.

[0153] (4) When the user operates the track scale change button 14a, a predetermined period begins, and the track 82, which is at a different scale from the detection result image 81, is drawn on the detection result image 81 and displayed in the display area 15a of the display device 15. This allows the user to display the detection result image 81 and the track 82, which is at a different scale, on the display device 15 at the timing desired by the user.

[0154] (5) The predetermined period ends when a predetermined time has elapsed since the user operated the track scale change button 14a to start the predetermined period. As a result, once a predetermined time has elapsed since the display of the track 82 with a different scale from the detection result image 81 began on the detection result image 81, the display of the detection result image 81 can be automatically returned to a display where the track 82 is drawn at the same scale as the detection result image 81, without any operation by the user.

[0155] Although the present invention has been described above based on embodiments, it is easy to infer that the present invention is not limited in any way to the above embodiments, and that various improvements and modifications are possible without departing from the spirit of the present invention. For example, each embodiment may be modified by adding or replacing some or more parts of the configuration of other embodiments with parts or more parts of the configuration of other embodiments, including the modifications described below. Furthermore, the numerical values ​​given in the above embodiments are merely examples, and it is naturally possible to use other numerical values.

[0156] In the above embodiment, when the user operates the track scale change button 14a, a predetermined period is started, and a track 82 with a different scale from the detection result image 81 is drawn on the detection result image 81 and displayed in the display area 15a of the display device 15. In contrast, the ultrasonic sonar device 12 may, instead of, or in addition to, the user's operation of the track scale change button 14a, start a predetermined period at specific time intervals (for example, every minute) and draw a track 82 with a different scale from the detection result image 81 on the detection result image 81 and display it in the display area 15a of the display device 15. This allows the detection result image 81 with a track 82 at a different scale drawn on it to be displayed automatically without any operation by the user, and the user can easily grasp the movement of the vessel 11 up to that point in conjunction with the detection result image 81.

[0157] In the above embodiment, a predetermined period is described in which, after a predetermined time has elapsed since the start of a predetermined period and the rendering of a track 82 with a different scale from the detection result image 81 on the detection result image 81, the predetermined period ends and the track 82 with the same scale as the detection result image 81 is rendered on the detection result image 81 again. However, instead of this, or in conjunction with this, the predetermined period may be terminated when the user operates one operation button 14 during the predetermined period. In this case, one operation button 14 may also be the track scale change button 14a, or a separate operation button 14 may be provided. This allows the display of the track 82 with a different scale from the detection result image 81 on the display device 15 to end at the timing desired by the user, according to the user's will, and the display of the track 82 with the same scale as the detection result image 81 to be displayed on the display device 15 again.

[0158] In the above embodiment, a display area 15a of the display device 15 may indicate that a predetermined period is currently in place, that is, that the track 82 displayed on the display device 15 is a track 82 with a different scale than the detection result image 81. For example, the color of the track 82 may be displayed in a different color than normal (periods other than the predetermined period) during the predetermined period. Also, while the track 82 is normally displayed as a solid light, it may be displayed as a blinking track 82 during the predetermined period. Furthermore, the information 84 indicating the scale of the track 82 may be displayed in a different color during the predetermined period and at other times (normal times), or the information 84 indicating the scale of the track 82 may be normally displayed as a solid light, while it may be displayed as a blinking track during the predetermined period. Additionally, textual information indicating that a predetermined period is currently in place (that the scale of the track 82 is different from the scale of the detection result image 81) may be displayed in the display area 15a of the display device 15. This allows the user to recognize at a glance that the track 82 displayed on the display device 15 is a track 82 with a different scale than the detection result image 81.

[0159] In the above embodiment, a PPI sonar (searchlight sonar) was described as an example of an ultrasonic sonar device 12. However, the present invention is not limited to PPI sonar, as long as it performs horizontal detection by transmitting and receiving ultrasonic TB. The present invention can be applied to any method, such as scanning sonar. Scanning sonar works by forming an array of multiple fine transducers on the surface of a cylindrical or spherical body, simultaneously transmitting ultrasonic waves from each transducer, and receiving the reflected waves to perform underwater detection around a ship at once. [Explanation of Symbols]

[0160] 11 Ships 12. Ultrasonic sonar device 14 Operation buttons 14a Track scale change button 15 Display device 16 Transmitter / Receiver Unit 18 GPS antennas 31. Oscillator 50 Control device 52 flash memory 52a Program Data 52b Change scale setting data 52c Horizontal detection tilt angle data 53a Tilt angle data 53b Scan angle data 53c Track scale change flag 61 Motor Driver 62 Transmit / Receive Circuit 63 Display Controller 64a Detection result image data 64b Track image data 65 GPS Interface 81 Detection result image 82 Wake GF Detectable Objects TB ultrasound

Claims

1. A transmitting and receiving unit that is attached to a ship and transmits ultrasonic waves over a predetermined range in the water set in all directions or in some directions from the ship, and receives reflected ultrasonic waves reflected from each position in the water for each predetermined direction, A detection result image generation means generates a detection result image that projects the detection results in a specific range of water from the vessel onto a plane parallel to the horizontal plane, based on the received signals for each predetermined direction that are generated based on the reflected waves received by the transmitting and receiving unit, An acquisition means for acquiring the position information of the ship at each unit of time, A track image generation means generates a track image for plotting the track of the vessel within the specified range on the detection result image, based on the position information of the vessel obtained by the acquisition means. The system includes a display control means that controls the display device to display the detection result image, in which the track is drawn using the aforementioned track image, The aforementioned track image generation means is characterized by generating a track image for drawing on the detection result image at a different scale than the detection result image, while aligning the track with the direction of the detection result image for a predetermined period of time.

2. The ultrasonic sonar device according to claim 1, further comprising a scale setting reception means for receiving in advance from the user the setting of the scale of the track in the track image generated by the track image generation means for the predetermined period.

3. The ultrasonic sonar device according to claim 1, characterized in that it is provided with an instruction means for the user to instruct the start of the predetermined period.

4. The ultrasonic sonar device according to claim 1, characterized in that the track image generation means terminates the predetermined period when a predetermined time has elapsed from the start of the predetermined period.

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