Laser irradiation system

Abstract

To provide a laser irradiation system which allows for appropriately setting a turning direction of an irradiation unit turned by a drive unit to sight a target.SOLUTION: A control device (70) is provided, comprising an acquisition unit (41) configured to acquire position information and moving direction information of a target and driving characteristics information of a drive unit (34), and a setting unit (42) configured to set a turning direction of an irradiation unit (12) turned by the drive unit (34) to sight a target on the basis of the position information, moving direction information, and driving characteristics information acquired by the acquisition unit (41).SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a laser irradiation system.

Background Art

[0002] A laser irradiation system according to the background art is disclosed in Patent Document 1 below. The laser irradiation system includes a drive mechanism that controls the elevation angle and the turning angle of a laser device, and a control unit controls the drive mechanism so that a laser is emitted toward a condensing point set based on target detection information.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the laser irradiation system disclosed in Patent Document 1, when turning a laser device that irradiates a laser toward a desired turning angle, specifically, setting an appropriate direction for turning the laser device according to the driving characteristics of the drive mechanism has not been studied.

[0005] An object of the present disclosure is to obtain a laser irradiation system capable of appropriately setting a turning direction for turning an irradiation unit by a drive unit for aiming at a target based on drive characteristic information of the drive unit.

Means for Solving the Problems

[0006] A laser irradiation system according to one aspect of the present disclosure is a laser irradiation system for irradiating a target with a laser, comprising: a laser irradiation device having an irradiation unit for irradiating a laser and a drive unit for rotating the irradiation unit; and a control device for controlling the laser irradiation device, wherein the control device has an acquisition unit for acquiring position information and movement direction information of the target and drive characteristic information of the drive unit; and a setting unit for setting a rotation direction for rotating the irradiation unit by the drive unit in order to aim at the target, based on the position information, movement direction information, and drive characteristic information acquired by the acquisition unit. [Effects of the Invention]

[0007] According to this disclosure, it is possible to appropriately set the rotation direction in which the drive unit rotates the illumination unit for aiming at a target, based on the drive characteristic information of the drive unit. [Brief explanation of the drawing]

[0008] [Figure 1] This figure schematically shows the overall configuration of the laser irradiation system according to the embodiment of this disclosure. [Figure 2] This is a side view specifically illustrating the configuration of the illumination optics and support mechanism. [Figure 3] This is a perspective view specifically showing the configuration of the illumination optics and support mechanism. [Figure 4] This figure shows the functional configuration of a laser irradiation system according to an embodiment of the present disclosure. [Figure 5] This flowchart shows an example of a control operation performed by the controller. [Figure 6A] This is a diagram illustrating the process of aiming at and tracking a target. [Figure 6B] This is a diagram illustrating the process of aiming at and tracking a target. [Figure 7] This flowchart explains how to set the rotation direction for targeting using a controller. [Figure 8] This figure shows the situation in the first example where a right turn was used for aiming. [Figure 9] This figure shows the situation in the first example where a left turn was used for aiming. [Figure 10] The second example shows a situation where the target is moving to the left relative to the center of rotation. [Figure 11] The second example shows a situation where the target is moving to the right relative to the center of rotation. [Modes for carrying out the invention]

[0009] Embodiments of this disclosure will be described in detail below with reference to the drawings. Elements denoted by the same reference numeral in different drawings are considered to be the same or corresponding elements.

[0010] [Overall System Configuration] Figure 1 is a schematic diagram showing the overall configuration of a laser irradiation system according to an embodiment of this disclosure. The laser irradiation system according to this embodiment is a laser system for rendering a target incapable of flight by irradiating the target with a high-power laser from a laser irradiation device 1. The purpose of irradiating a target with a laser can be, for example, to transmit power via a laser to an aircraft or flying object that is driven by electricity and autonomously steers itself. Alternatively, it can be used to repel or render incapable of flight a harmful object that is flying or in flight by irradiating it with a high-power laser. In this case, the harmful object may be, for example, a harmful bird or animal that is flying or in flight.

[0011] The laser irradiation system according to this embodiment is mounted on a vehicle 101, which is a mobile unit. The vehicle 101 comprises an engine 102 as a power source, wheels 103 that are rotationally driven by the engine 102, a cabin 104 that houses a driver's seat, a frame 105 connected to the cabin 104, and a container 106 supported by the frame 105. The laser irradiation device 1 is located in the container 106. The container 106 also houses a radar detector 110 that detects targets using radar.

[0012] The laser irradiation device 1 includes a laser oscillator 11, an irradiation optical device 12, and a support mechanism 13. The laser oscillator 11 is a light source that generates a laser Lb. The irradiation optical device 12 is an irradiator that guides and irradiates the laser Lb generated by the laser oscillator 11 in a desired direction. The support mechanism 13 is a mechanism that supports the irradiation optical device 12 so that it can rotate and tilt.

[0013] The laser oscillator 11 is disposed inside the container 106, and the irradiation optical device 12 and the support mechanism 13 are disposed on the container 106. Note that the container 106 may be configured not only as an accommodation chamber for accommodating the laser oscillator 11 but also, for example, as an operator's room where an operator stays.

[0014] The laser Lb generated by the laser oscillator 11 may be of any type as long as it is a high-power laser. For example, an iodine laser or a fiber laser is suitable. The iodine laser is a type of gas laser generated by a chemical reaction between excited oxygen and iodine. When using an iodine laser, the laser oscillator 11 may include, for example, an excited oxygen generator that generates excited oxygen, an iodine supply device that supplies iodine that reacts with the excited oxygen generated from the device, and a laser resonator that causes laser oscillation by a chemical reaction between excited oxygen and iodine. Further, the fiber laser is a type of electrically driven laser that oscillates a laser with an optical fiber added with a laser active element, and has advantages such as high-efficiency oscillation and high beam quality. When using a fiber laser, the laser oscillator 11 may include, for example, a semiconductor laser serving as an excitation light source, a coupler that couples the light of the semiconductor laser to an optical fiber added with an active element serving as a medium, and a laser resonator that extracts laser light from the optical fiber excited by the semiconductor laser.

[0015] Figures 2 and 3 are side and perspective views specifically showing the configurations of the irradiation optical device 12 and the support mechanism 13. In the present embodiment, for the sake of convenience, the extending direction of the Z-axis (described later), which is the rotation axis of the support mechanism 13 shown in FIG. 2 and the like, is defined as the vertical direction, the extending direction of the Y-axis is defined as the left-right direction, the direction in which the container 106 of the vehicle 101 exists as viewed from the laser irradiation device 1 is defined as the downward direction of the Z-axis, and the direction in which the irradiation optical device 12 irradiates the laser is defined as the forward direction. However, this direction definition can be appropriately changed depending on the mounting posture of the laser irradiation device 1 on the vehicle 101. The irradiation optical device 12 includes a housing 21, an optical module 22, an irradiation window 23, a tracking camera 24, and a photographing window 25. The housing 21 is a substantially rectangular tubular housing that houses the optical module 22 and the tracking camera 24 inside. The optical module 22 is a group of optical components that condense the laser Lb output from the laser oscillator 11 and direct it in a desired direction, and is composed of optical elements including transmission optical elements or reflection optical elements. An example of a transmission optical element is a condenser lens or a refractive lens, and an example of a reflection optical element is a concave mirror or a convex mirror. The irradiation window 23 is a transparent member made of a glass plate or the like that can transmit the laser Lb output from the optical module 22, and is attached to the front end surface 21a of the housing 21 that serves as the exit of the laser Lb. The tracking camera 24 is an imaging device that captures a target for aiming at the target and tracking the target. The photographing window 25 is a transparent member made of a glass plate or the like that is attached to the front end surface 21a of the housing 21 for taking in an image by the tracking camera 24.

[0016] The irradiation optical device 12 irradiates the laser Lb through the irradiation window 23 from the optical module 22 in a state where the posture is controlled so as to direct the target captured by the tracking camera 24. Thereby, the laser Lb can be made to hit the target, and thereby damage can be inflicted on the target.

[0017] The irradiation window 23 and the imaging window 25 are airtightly attached to the front end surface 21a of the housing 21. In other words, the inside of the housing 21 is sealed. Dry gas is sealed inside this sealed housing 21. The dry gas fills the inside of the housing 21 and removes air, thereby reducing the amount of water vapor or impurities remaining inside the housing 21. This prevents water vapor from absorbing the laser Lb passing through the housing 21, and consequently prevents the refractive index of the laser Lb from changing due to the temperature rise associated with the absorption of the laser.

[0018] The support mechanism 13 is a so-called two-axis gimbal mechanism. Supported by this support mechanism 13, the illumination optical unit 12 can rotate around the Z axis, as shown by arrow A1 in Figure 2, and can also tilt around the Y axis, which is perpendicular to the Z axis, as shown by arrow A2 in Figure 2.

[0019] Specifically, the support mechanism 13 comprises a base 31, a swivel body 32, a pair of left and right support legs 33, and a Z-axis motor 34 and a Y-axis motor 35 as shown in Figure 4. In this embodiment, the base 31 is a disc-shaped platform fixed to the container 106. The swivel body 32 is a disc-shaped rotating body coaxially arranged on the base 31 and is pivotally supported by the base 31 via a swivel shaft 31a extending in the Z-axis direction. The pair of support legs 33 are members that protrude upward from the swivel body 32 and are arranged to sandwich the illumination optical device 12 from both sides in the Y-axis direction. Each support leg 33 pivotally supports the illumination optical device 12 via a tilting shaft 33a extending in the Y-axis direction. The Z-axis motor 34 is an electric motor that rotates the swivel body 32 around the Z-axis as shown by arrow A1. The Y-axis motor 35 is an electric motor that rotates the illumination optical device 12 around the Y-axis as shown by arrow A2.

[0020] In response to the rotational drive of the swivel body 32 by the Z-axis motor 34, the illumination optical unit 12 rotates around the Z-axis together with the support legs 33. Also, in response to the drive of the Y-axis motor 35, the illumination optical unit 12 tilts around the Y-axis relative to the support legs 33. By being supported by the support mechanism 13 in a state that allows for such rotation and tilting, the illumination optical unit 12 can orient its front end surface 21a, which has the illumination window 23 and the imaging window 25, in all directions.

[0021] The illumination optics 12 and the laser oscillator 11 are connected via a light guide path 18, which is simplified as shown in Figure 3. The light guide path 18 is a path for introducing the laser Lb output from the laser oscillator 11 into the optical module 22 inside the illumination optics 12. The extension direction of each part of the light guide path 18 coincides with the extension direction of the Y-axis or Z-axis. When irradiating a target with laser Lb, the laser Lb is introduced from the laser oscillator 11 into the optical module 22 through the light guide path 18. The laser Lb introduced into the optical module 22 is led out to the outside through the irradiation window 23. Note that the extension direction of each part of the light guide path 18 does not necessarily have to coincide with the extension direction of the Y-axis or Z-axis.

[0022] Figure 4 is a block diagram showing the functional configuration of the laser irradiation system according to this embodiment. The laser irradiation system includes a controller 70 as a control device. The laser irradiation system also includes a laser irradiation device 1, a radar detector 110, and a distance measuring device 51, all of which are electrically connected to the controller 70. The distance measuring device 51 is configured using any rangefinder to measure the distance from the laser irradiation device 1 to the object to be measured. The distance measuring device 51 may also be mounted on the laser irradiation device 1. The controller 70 includes an acquisition unit 41, a setting unit 42, and an output unit 43. Details of the functions of each processing unit will be described later. The controller 70 controls the driving of the laser oscillator 11, tracking camera 24, Z-axis motor 34, and Y-axis motor 35 of the laser irradiation device 1.

[0023] [Example of operation] Figure 5 is a flowchart showing an example of the control operation of the laser irradiation device 1 to irradiate a target with a laser, as performed by the controller 70. First, in step S1, the controller 70 activates the radar detector 110. For example, an operator who recognizes the need for laser irradiation inputs an activation command for the radar detector 110 to the controller 70. As a result, the controller 70 activates the radar detector 110.

[0024] When the radar detector 110 is activated, in step S2 the controller 70 determines whether or not the radar detector 110 has detected a target to be dealt with. If the target to be dealt with is not detected (step S2: NO), the controller 70 repeats the process in step S2.

[0025] If a target is detected (step S2: YES), then in step S3, the controller 70 performs targeting and tracking of the target using the tracking camera 24. That is, the controller 70 controls the attitude of the illumination optics 12 using the Z-axis motor 34 and Y-axis motor 35 so that the target detected by the radar detector 110 is within the field of view of the tracking camera 24, and causes the tracking camera 24 to continuously photograph the target. The setting of the rotation direction of the illumination optics 12 for targeting will be explained in detail in the first and second examples described later. When the radar detector 110 detects a target, the radar detector 110 may simultaneously obtain distance information between the target and the laser irradiation device 1, and direction information of the target as seen from the laser irradiation device 1, and transmit this information to the controller 70. In this embodiment, the controller 70 estimates the position of the target based on the information obtained from the radar detector 110 and the tracking camera 24.

[0026] Next, in step S4, the controller 70 determines whether or not the target tracking has converged.

[0027] Figures 6A and 6B are diagrams illustrating targeting and tracking, and show images captured by the tracking camera 24. In Figure 6A, point X1 indicates the tracking point, and point X2 indicates the laser target. Tracking point X1 is a reference point included in the target image, and laser target X2 is the destination of the laser Lb emitted from the illumination optics 12. The controller 70 controls the attitude of the illumination optics 12 so that tracking point X1 coincides with the laser target X2, that is, from the state in Figure 6A to the state in Figure 6B. Then, when a stable aiming state in which tracking point X1 approximately coincides with the laser target X2 is obtained, the controller determines that tracking has converged.

[0028] If it is determined that tracking has converged (step S4: YES), then in step S5, the controller 70 irradiates the target with laser Lb. That is, the controller 70 controls the laser oscillator 11 so that laser Lb is input from the laser oscillator 11 to the irradiation optics 12. As a result, laser Lb is introduced into the optical module 22 and irradiated from the optical module 22 through the irradiation window 23.

[0029] If it is determined that tracking has not converged (step S4: NO), the controller 70 repeatedly executes the processes in steps S3 and S4.

[0030] Next, in step S6, the controller 70 determines whether or not the target has been dealt with. The specific determination varies depending on the purpose of the laser irradiation, but for example, when the laser irradiation is performed for the purpose of wirelessly supplying power to an autonomously flying or soaring target, if the target is moving, it is necessary to continue tracking the target for a certain period of time or longer while irradiating the target with the laser Lb. The determination of whether to continue or interrupt the power supply may be made, for example, by determining whether the time during which the target and the laser target X2 have been approximately in sync exceeds a predetermined period of time, or by equipping the target with a sensor to determine the amount of charge, a control device to determine whether the charge is sufficient, and a wireless device to transmit this wirelessly, thereby transmitting the target's charge status to the laser irradiation device 1 for determination. When the purpose is to repel harmful birds or animals in flight or soaring, for example, the controller 70 determines whether or not the harmful birds or animals have been repelled from the observation range, or whether or not the birds or animals have lost their ability to fly, by analyzing images captured by the tracking camera 24. If it is determined that the target has not been addressed (step S6: NO), the controller 70 repeats the processes in steps S5 and S6.

[0031] If it is determined that the target has been dealt with (step S6: YES), then in step S7, the controller 70 determines whether or not other targets exist. That is, the controller 70 determines whether or not there are any targets detected by the radar detector 110 in addition to the targets that have already been dealt with.

[0032] If it is determined that another target exists (Step S7: YES), the controller 70 repeatedly executes the processes from Step S3 onward to target, track, and deal with the other target.

[0033] If it determines that no other targets exist (step S7: NO), the controller 70 terminates the process.

[0034] As described above, the laser irradiation system according to this embodiment irradiates a target with a laser Lb, and the controller 70 controls the attitude of the irradiation optics 12, that is, the rotation angle and depression angle of the irradiation optics 12, by driving the Z-axis motor 34 and the Y-axis motor 15 for aiming and tracking the target.

[0035] In this embodiment, regarding the rotation for aiming at a target detected by the radar detector 110, there are two options: rotation in the leftward direction and rotation in the rightward direction around the Z-axis, and it is necessary to set one of these rotation directions. Note that the leftward rotation and rightward rotation described here refer to the rotation direction when the laser irradiation device 1 is viewed from above in the Z-axis direction. It is common to set the rotation direction to the one with the smaller rotation amount based on the target's position information, but this is not always optimal. Therefore, in the laser irradiation system according to this embodiment, the controller 70 sets the rotation direction for aiming at the target based on the drive characteristic information of the drive unit including the Z-axis motor 34.

[0036] Furthermore, in the following explanation, when the target moves, the direction of movement may be described as movement in the leftward rotation direction or movement in the rightward rotation direction, based on the viewpoint on the Z-axis, which is the center of rotation. That is, when the laser irradiation direction of the laser irradiation device 1, which rotates around the Z-axis, is considered as the direction the viewpoint is facing the target, the horizontal component of the target can be expressed as a change in the azimuth angle around the Z-axis, such as a rightward rotation direction or a leftward rotation direction.

[0037] Figure 7 is a flowchart illustrating the method used by the controller 70 to set the rotation direction for targeting. The flowchart in Figure 7 is a more detailed representation of the targeting process in step S3 of the flowchart in Figure 5.

[0038] First, in step S11, the acquisition unit 41 acquires the target's position information and direction of movement information based on the target detection information input from the radar detector 110.

[0039] Next, in step S12, the acquisition unit 41 acquires drive characteristic information of the drive unit. In the first example described later, the drive characteristic information includes limit information for the angular velocity and angular acceleration of the rotation. In the second example described later, the drive characteristic information includes limit information indicating the first rotation range when the illumination optical device 12 is rotated in the first direction and the second rotation range when the illumination optical device 12 is rotated in the second direction. The first rotation range is the angular range in which the support mechanism 13 can rotate in the first direction starting from the reference axis V described later, and the second rotation range is the angular range in which the support mechanism 13 can rotate in the second direction starting from the reference axis V described later.

[0040] Next, in step S13, the setting unit 42 sets the rotation direction for aiming at the target based on the target's position information, movement direction information, and drive characteristic information of the drive unit acquired by the acquisition unit 41.

[0041] Next, in step S14, the output unit 43 outputs drive information including the rotation direction set by the setting unit 42. The output drive information is input to the laser irradiation device 1.

[0042] The following describes in detail the first and second examples of methods for setting the turning direction for aiming at a target.

[0043] [Example 1] In the first example, it is assumed that a laser irradiation device 1 of the type in which the swivel range of the drive unit, including the Z-axis motor 34, is not limited and the irradiation optics 12 can swivel without limit is employed.

[0044] In the first example, the system estimates which path—a right turn or a left turn—to begin the rotation from the direction the illumination optics 12 is currently facing, relative to the final position where the laser irradiation device 1 is aimed at the target and laser irradiation begins. Based on this estimate, the direction in which the rotation begins is determined. For reasons described later, one of the rotation paths, either a left turn or a right turn, must reverse direction at least once from the initial rotation direction to the opposite direction. The other path, on the other hand, does not involve a reversal of the rotation direction, but the angle change of the rotation path is larger than that of the other path. Even if the controlled laser irradiation device 1 is the same, the time required to complete the rotation differs depending on the combination of the direction the illumination optics 12 is facing at the start of the rotation and the direction of the target as seen from the Z-axis at the start of the rotation.

[0045] In the first example, the drive characteristics information includes limit information for the angular velocity and angular acceleration of the rotation. This limit information includes, for example, upper limits for the angular velocity and angular acceleration of the rotation. These upper limits are determined according to the weight of the illumination optics 12, the motor torque and power of the Z-axis motor 34, and the permissible upper limits for vibrations that occur during rapid deceleration or rapid acceleration. This drive characteristics information, including these upper limits, is pre-databased and stored in the internal memory of the controller 70 or in an external memory accessible by the controller 70. However, instead of pre-storing the databased drive characteristics information in the system's internal memory, the controller 70 may be configured to obtain the necessary drive characteristics information by communication from an external server device or the like each time it performs control.

[0046] In the following explanation, the position to which the illumination optical device 12 is facing when the rotation direction is reversed in a rotation path starting from the first direction which requires a reversal of the rotation direction will be defined as the reversal position. In contrast, the position to which the illumination optical device 12 is facing when it aims at the target and starts laser irradiation will be defined as the aiming position.

[0047] Figure 8 shows the situation in the first example where a rightward rotation is used to aim the illumination optics 12 at the target, and Figure 9 shows the situation in the first example where a leftward rotation is used to aim the illumination optics 12 at the target.

[0048] Position P(t) is the position of the target detected by the radar detector 110 at the current time t. Position R is the point on the extension of the direction the illumination optics 12 is pointing at the moment the laser irradiation device 1 changes from right rotation to left rotation. As defined above, position R is the inversion position in this case. Also, in this case, as viewed from the rotation center, position R is somewhere within the angular range between position P(t) and position P(t+β1), which will be described later. The angle between the direction from the rotation center toward position R and the direction of an arbitrary reference axis H is angle θ1. Note that the angle between the direction from the rotation center toward position P(t) and the direction of the reference axis H may be equal to angle θ1.

[0049] Position P(t-α) is the position of the target detected by the radar detector 110 at past time t-α.

[0050] Position P(t+β1) is the predicted position of the target at a future time t+β1. The angle between the direction from the pivot center toward position P(t+β1) and the direction of the reference axis H is angle θ2. The predicted position P(t+β1) is calculated by the setting unit 42 using the orientation information of position P(t), the orientation information of position P(t-α), and the elapsed time information between time t-α, time t, and time t+β1. Furthermore, the setting unit 42 can calculate position P(t+β1) with higher accuracy by further using the distance information from the laser irradiation device 1 to position P(t-α) and the distance information from the laser irradiation device 1 to position P(t), which are measured by the distance measuring device 51.

[0051] Arrow C indicates the direction the illumination optics 12 is pointing at the current time t. The angle between the direction of arrow C and the direction of the reference axis H is angle θ0.

[0052] As shown in Figure 8, when a right turn is adopted for aiming at a target moving in a counter-clockwise direction relative to the rotation center, the illumination optics 12 first rotates in the direction indicated by arrow F1, stops rotating at a rotation angle that points to position R, and then rotates in the direction indicated by arrow F2 to follow the target's movement and aim at the target. In other words, when aiming at the target, the rotation path will have to be reversed at some point. In this case, rapid deceleration and rapid acceleration are required when the rotation is reversed.

[0053] On the other hand, as shown in Figure 9, when a left turn is adopted for aiming at a target moving in a counter-clockwise direction relative to the rotation center, aiming is completed without reversing the rotation direction, as indicated by arrows F3 and F4. Position P(t+β2) is the predicted position of the target at a future time t+β2. The angle between the direction from the rotation center toward position P(t+β2) and the direction of the reference axis H is angle θ3. In this case, there is no sudden deceleration or acceleration caused by reversal.

[0054] As shown in Figure 8, the setting unit 42 calculates the time from the current angle θ0 to the angle θ2, which is the angle at which aiming is completed and tracking begins, as the first required time β1, based on the information acquired by the acquisition unit 41, when the illumination optical device 12 is rotated in a clockwise direction with a reversal of the rotation direction. Also, as shown in Figure 9, the setting unit 42 calculates the time from the current angle θ0 to the angle θ3, which is the angle at which aiming is completed and tracking begins, as the second required time β2, based on the information acquired by the acquisition unit 41, when the illumination optical device 12 is rotated in a counterclockwise direction without a reversal of the rotation direction. In other words, in the first example described so far, the clockwise rotation direction is the first direction, and the counterclockwise rotation direction is the second direction. The definition of the first required time is the time from when the illumination optical device 12 starts rotating in a certain direction until aiming is completed after a reversal, while the definition of the second required time is the time from when the illumination optical device 12 starts rotating in a certain direction until aiming is completed without a reversal. Therefore, the first and second directions are not limited to left-right rotation directions; for example, the left rotation direction may be the first direction and the right rotation direction may be the second direction.

[0055] As described above, the drive unit of the laser irradiation device 1, including the Z-axis motor 34, has drive characteristics such as limitations on the angular velocity and angular acceleration of rotation. When the irradiation optical device 12 rotates from its current position to a certain position to the right or left, the Z-axis motor 34 accelerates within a certain rotation range to reach a predetermined limited rotation speed, and then stops by braking to decelerate within a certain rotation range. The time until the rotation is completed is obtained as the sum of all the times for the accelerated rotation, constant-speed rotation, and decelerated rotation described above. Therefore, in the first example, the time for accelerated rotation and the time for decelerated rotation are always approximately twice as long in the first required time β1 compared to the second required time β2, while the total value of the range of rotation at a constant speed differs depending on the angle θ0 between the direction of arrow C and the direction of the reference axis H. For this reason, the relative magnitudes of the first required time β1 and the second required time β2 change depending on the circumstances.

[0056] The setting unit 42 compares the first required time β1 and the second required time β2. If the first required time β1 is less than the second required time β2, the rotation direction is set to the right rotation direction shown in Figure 8. If the first required time β1 is greater than the second required time β2, the rotation direction is set to the left rotation direction shown in Figure 9. If the first required time β1 and the second required time β2 are equal, either the right rotation direction or the left rotation direction may be adopted.

[0057] [Second example] In the second example, it is assumed that a type of laser irradiation device 1 is employed in which the swivel range of the drive unit, including the Z-axis motor 34, is limited. One reason for limiting the swivel range of the drive unit is that, in order to eliminate relatively complex or expensive mechanisms such as slip rings as connection mechanisms for electrical signals or cooling water in the rotating part, a cable or hose is used to connect the rotating irradiation optical unit 12 and the device in the container 106. In this case, the swivel range of the drive unit is limited to a range in which twisting of the cable or hose does not impair the function of the component. If the swivel range is not unlimited, there is no need to adopt a special structure for the wiring or piping between the base 31 and the rotating body 32, and thus the cost can be reduced by simplifying the swivel mechanism.

[0058] In the second example, the rotation angle of the laser irradiation device 1 has a left rotation limit position beyond which it cannot rotate left, and a right rotation limit position beyond which it cannot rotate right. In addition, since the laser irradiation device 1 is allowed to rotate more than 360°, there is an overlapping range AR, described later, which is sandwiched between the left rotation limit position and the right rotation limit position within the entire rotation range. If the direction in which the target is located lies on the extension of this overlapping range AR, depending on the direction in which the target moves in the future, it may become difficult to keep the irradiation optics 12 aiming at the target due to the rotation limit position. For this reason, by estimating the direction in which the target will move in the future and determining the rotation direction based on that information, it is possible to maintain aiming even if the target moves outside the overlapping range AR.

[0059] In the second example, the drive characteristic information includes limiting information indicating the range of left rotation when the illumination optical device 12 is rotated counterclockwise starting from the reference axis V (described later), and the range of right rotation when the illumination optical device 12 is rotated clockwise starting from the reference axis V. This drive characteristic information, including the limiting information, is pre-databased and stored in the internal memory of the controller 70 or in an external memory accessible by the controller 70. However, instead of pre-storing the databased drive characteristic information in the system's internal memory, the controller 70 may obtain the necessary drive characteristic information from an external server device or the like via communication each time it performs control.

[0060] Figure 10 shows the situation in the second example where the target is moving in a counter-clockwise direction relative to the center of rotation, and Figure 11 shows the situation in the second example where the target is moving in a clockwise direction relative to the center of rotation.

[0061] With respect to the reference axis V, which corresponds to the front direction of the illumination optical device 12, the left rotation range in this embodiment is slightly greater than 180 degrees, for example, 200 degrees. Similarly, the right rotation range with respect to the reference axis V is also slightly greater than 180 degrees, for example, 200 degrees. Therefore, an overlapping range AR exists on the opposite side of the front direction where the left rotation range and the right rotation range overlap. When a target is detected within this overlapping range AR, it is necessary to select either left rotation or right rotation as the rotation direction for aiming the illumination optical device 12.

[0062] Position P(t) is the position of the target detected by the radar detector 110 at the current time t. The angle between the direction from the rotation center toward position P(t) and the direction of the reference axis V, which corresponds to the front direction of the illumination optical device 12, is defined as angle θ1L when measured in the counterclockwise direction from the reference axis V, and angle θ1R when measured in the clockwise direction from the reference axis V.

[0063] Position P(t-α) is the position of the target detected by the radar detector 110 at past time t-α.

[0064] In the situation shown in Figure 10, the setting unit 42 determines, based on the current position P(t) and the past position P(t-α), that the target is moving in a counter-clockwise direction relative to the rotation center. On the other hand, in the situation shown in Figure 11, the setting unit 42 determines, based on the current position P(t) and the past position P(t-α), that the target is moving in a clockwise direction relative to the rotation center. Furthermore, the setting unit 42 can calculate with high accuracy by further using the distance information from the laser irradiation device 1 to position P(t-α) and the distance information from the laser irradiation device 1 to position P(t), which are measured by the distance measuring device 51.

[0065] Arrow C indicates the direction the illumination optics unit 12 is pointing at the current time t. The angle θ0 is defined as the angle formed by the direction of arrow C and the direction of the reference axis V at time t.

[0066] If a target is detected within the overlapping range AR, the setting unit 42 sets the rotation direction for aiming the illumination optical unit 12 based on the limiting information indicating the rotation range, so that the rotation of the illumination optical unit 12 does not reach the rotation limit of the rotation range during the laser irradiation stage after tracking convergence.

[0067] Specifically, if the direction of movement of a target detected within the overlapping range AR is a left rotation direction, which is the first direction when viewed from the rotation center, the setting unit 42 sets the rotation direction for aiming at the target to a right rotation direction, which is the second direction, as shown by arrow F5 in Figure 10. This allows the target to be tracked by the left rotation of the illumination optics 12, even if the target deviates from the overlapping range AR from position P(t) and moves further in a left rotation direction when viewed from the rotation center, and the laser Lb can be continuously irradiated onto the target for a certain period of time or longer. Also, if the direction of movement of a target detected within the overlapping range AR is a right rotation direction, which is the second direction when viewed from the rotation center, the setting unit 42 sets the rotation direction for aiming at the target to a left rotation direction, which is the first direction, as shown by arrow F6 in Figure 11. As a result, even if the target moves further to the right from position P(t) in the overlapping range AR relative to the rotation center, the target can be tracked by the rightward rotation of the illumination optics 12, and the laser Lb can be continuously irradiated onto the target for a certain period of time or longer.

[0068] Furthermore, if the target's movement speed is slow and it is expected that the target will not deviate from the overlapping range (AR) from the start of laser irradiation to the completion of the response, the setting unit 42 may adopt either a left rotation direction or a right rotation direction as the rotation direction for aiming the irradiation optics unit 12. Preferably, the rotation direction that requires less time to rotate should be adopted based on the target's position information. Also, in the second example, as in the first example, the first and second directions are not limited to left or right rotation directions; for example, the right rotation direction may be the first direction and the left rotation direction may be the second direction.

[0069] Furthermore, in the flowcharts shown in Figures 5 and 7, the execution order or timing of each process is not particularly limited and can be changed as appropriate, as long as the same objective can be achieved.

[0070] Furthermore, the functions of each element, including the controller 70 disclosed in this disclosure, can be performed using circuits or processing circuits, including general-purpose processors, dedicated processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the enumerated functions, or hardware programmed to perform the enumerated functions. The hardware may be hardware disclosed herein, or other known hardware that is programmed or configured to perform the enumerated functions. If the hardware is a processor, which is considered a type of circuit, then the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or the processor.

[0071] [Effects and Effects] According to the laser irradiation system of this embodiment, the acquisition unit 41 acquires target position information and movement direction information. The acquisition unit 41 also acquires drive characteristic information of the drive unit. The setting unit 42 sets the rotation direction for aiming at the target based on the position information, movement direction information, and drive characteristic information acquired by the acquisition unit 41. In this way, by using the position information, movement direction information, and drive characteristic information, it becomes possible to appropriately set the rotation direction in which the irradiation unit is rotated by the drive unit for aiming at the target.

[0072] [Summary of this disclosure] The embodiments of this disclosure described above can be summarized as follows:

[0073] A laser irradiation system according to one aspect of the present disclosure is a laser irradiation system for irradiating a target with a laser, comprising: a laser irradiation device having an irradiation unit for irradiating a laser and a drive unit for rotating the irradiation unit; and a control device for controlling the laser irradiation device, wherein the control device has an acquisition unit for acquiring position information and movement direction information of the target and drive characteristic information of the drive unit; and a setting unit for setting a rotation direction for rotating the irradiation unit by the drive unit in order to aim at the target, based on the position information, movement direction information, and drive characteristic information acquired by the acquisition unit.

[0074] According to this embodiment, by using position information, movement direction information, and drive characteristic information, it becomes possible to appropriately set the rotation direction in which the drive unit rotates the illumination unit for aiming at a target.

[0075] In the above embodiment, the drive characteristic information includes limit information for the angular velocity and angular acceleration of the turn, and the setting unit calculates a first time required until aiming is completed when turning in a first direction to aim at the target, and then reversing the direction of the turn before aiming, and a second time required until aiming is completed when turning in a second direction to aim at the target, and then aiming without reversing the direction of the turn, based on the limit information, and sets the turning direction to the first direction if the first time required is less than the second time required, and sets the turning direction to the second direction if the first time required is greater than the second time required.

[0076] According to this embodiment, it becomes possible to appropriately set the rotation direction for aiming at the target in such a way that the time required to complete aiming is shortened.

[0077] In the above embodiment, the drive characteristic information includes limiting information indicating a first rotatable range when the irradiation unit is rotated in a first direction and a second rotatable range when the irradiation unit is rotated in a second direction different from the first direction, and there is an overlapping range in which the first rotatable range and the second rotatable range partially overlap, and when the target is detected within the overlapping range, the setting unit sets the rotation direction to the first direction or the second direction based on the limiting information so that the rotation of the irradiation unit does not reach the rotation limit of the first rotatable range or the second rotatable range during the laser irradiation stage after tracking convergence.

[0078] According to this embodiment, it is possible to appropriately set the rotation direction for aiming at the target so as not to reach the rotation limit during the laser irradiation stage.

[0079] In the above embodiment, the setting unit sets the rotation direction to the second direction if the direction of movement of the target detected within the overlapping range is the first direction when viewed from the rotation center of the irradiation unit, and sets the rotation direction to the first direction if the direction of movement of the target detected within the overlapping range is the second direction when viewed from the rotation center of the irradiation unit.

[0080] According to this embodiment, it is possible to easily set the rotation direction for aiming at the target based on the target's direction of movement.

[0081] In the above embodiment, the acquisition unit further acquires distance information from the laser irradiation device to the target, and the setting unit sets the rotation direction based on the position information, the movement direction information, the drive characteristic information, and the distance information.

[0082] According to this embodiment, by further using distance information, it becomes possible to set the turning direction for aiming at a target more accurately. [Explanation of Symbols]

[0083] 1. Laser irradiation device 12 Irradiation optics 34 Z-axis motor 41 Acquisition Department 42 Setting section 43 Output section 51 Distance measuring device 70 Controllers

Claims

1. A laser irradiation system that irradiates a target with a laser, A laser irradiation device having an irradiation unit that emits a laser and a drive unit that rotates the irradiation unit, A control device for controlling the laser irradiation device, Equipped with, The control device is An acquisition unit that acquires the position information and movement direction information of the target, and drive characteristic information including limiting information for the angular velocity and angular acceleration that the drive unit rotates the irradiation unit, The system includes a setting unit that sets a rotation direction for the drive unit to rotate the illumination unit for aiming at the target, based on the position information, movement direction information, and drive characteristic information acquired by the acquisition unit. The setting unit calculates, based on the limitation information, a first time required until aiming is completed when the vehicle rotates in a first direction and then reverses direction of rotation before aiming at the target, and a second time required until aiming is completed when the vehicle rotates in a second direction and then aims without reversing direction of rotation before aiming at the target. If the first required time is less than the second required time, the turning direction is set to the first direction; if the first required time is greater than the second required time, the turning direction is set to the second direction. Laser irradiation system.

2. A laser irradiation system for irradiating a target with a laser, A laser irradiation device having an irradiation unit that emits a laser and a drive unit that rotates the irradiation unit, A control device for controlling the laser irradiation device, Equipped with, The control device is An acquisition unit that acquires the position information and movement direction information of the target, and drive characteristic information including limiting information indicating a first rotation range when the drive unit rotates the irradiation unit in a first direction and a second rotation range when the irradiation unit rotates the irradiation unit in a second direction different from the first direction, The system includes a setting unit that sets a rotation direction for the drive unit to rotate the illumination unit for aiming at the target, based on the position information, movement direction information, and drive characteristic information acquired by the acquisition unit. There is an overlapping range in which the first swivel range and the second swivel range partially overlap. When the target is detected within the overlapping range, the setting unit sets the rotation direction to the first direction or the second direction based on the limitation information, so that the rotation of the irradiation unit does not reach the rotation limit of the first rotation range or the second rotation range during the laser irradiation stage after tracking convergence. Laser irradiation system.

3. The aforementioned setting unit is, If the direction of movement of the target detected within the overlapping range is the first direction when viewed from the rotation center of the irradiation unit, the rotation direction is set to the second direction. The laser irradiation system according to claim 2, wherein if the direction of movement of the target detected within the overlapping range is the second direction when viewed from the rotation center of the irradiation unit, the rotation direction is set to the first direction.

4. The acquisition unit further acquires distance information from the laser irradiation device to the target, The laser irradiation system according to any one of claims 1 to 3, wherein the setting unit sets the rotation direction based on the position information, the movement direction information, the drive characteristic information, and the distance information.

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