JP6986706B2 - Water mobile control device - Google Patents

Description

The present invention relates to a water mobile body control device that mainly controls a water mobile body used for maintenance and inspection work, repair work, and the like of a pier, a pier, and the like.

Conventionally, in harbor structures such as piers, workers are on board small boats and water-moving bodies such as work rafts to perform inspection work and repair work.

Since the water moving body is not stable due to waves and tidal currents, for example, a rope or the like is wrapped around a pile supporting the pier to fix the water moving body, and the work is performed in that state. ing.

However, it is difficult to fix the floating body to a pile or the like by one person, and in the case of a work involving movement, it is necessary to repeat the fixing work to the pile or the like and the detaching work for each movement, which is complicated. there were.

Therefore, in recent years, a method has been developed in which the position of a water moving body is measured using GNSS, the thruster is controlled based on the position information, and the water moving body is maintained at a predetermined position (for example). , Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-24421

However, in the conventional technique as described above, there is a problem that it is often difficult to measure the position because the radio wave is blocked by the structure because the work is often performed by invading the superstructure of the pier.

Therefore, in view of such conventional problems, the present invention has been made to provide a water mobile body control device capable of appropriately specifying a position even under a pier or a bridge and maintaining a predetermined position. It is a thing.

The feature of the invention according to claim 1 for solving the above-mentioned conventional problem is in the water moving body control device for maintaining a predetermined position by the water moving body provided with a plurality of propulsion means. Processing conversion based on the camera installed in the moving object, a plurality of feature amount calculation means having different algorithms for calculating the feature amount of the image taken by the camera, and the feature amount calculated by each feature amount calculation means. A conversion processing means for calculating a matrix and calculating the movement amount and rotation amount of the water moving body by the processing transformation matrix, and the plurality of propulsion means based on the movement amount and rotation amount calculated by the conversion processing means. The control means includes a control means for controlling, and the control means has a difference in the closest value of the movement amount or rotation amount of the water moving body calculated based on the feature amount calculated by each feature amount calculation means within a predetermined range. It is provided with a determination unit for determining whether or not it belongs to, and a control value determination unit for calculating the average value of two movement amounts and rotation amounts belonging to the predetermined range, and the plurality of units based on the average value of the movement amount and rotation amount. The propulsion means of the above is controlled so that the water moving body can maintain the predetermined position.

A feature of the invention according to claim 2 is, in addition to the configuration of claim 1, a gimbal mechanism that rotatably supports the camera in the horizontal direction and the vertical direction, a gimbal control means for controlling the gimbal mechanism, and the camera. It is provided with a swing detecting means for detecting the swing of the camera so that the orientation of the camera is automatically maintained in a desired direction.

The feature of the invention according to claim 3 is a method of controlling a water moving body for maintaining a water moving body provided with a plurality of propulsion means in a predetermined position, which is photographed by a camera installed on the water moving body. The feature amount of the image is calculated by a plurality of feature amount calculation means having different algorithms, a processing transformation matrix is calculated based on the calculated feature amount, and the movement amount and rotation amount of the water moving body are calculated by the processing transformation matrix. After calculating, it is determined whether the difference between the closest values of the movement amount or the rotation amount of the water moving body calculated based on the feature amount calculated by each feature amount calculation means belongs to the predetermined range. The average value of the two movement amounts and the rotation amounts belonging to the predetermined range is calculated, the water moving body is controlled based on the average value of the movement amount and the rotation amount, and the water moving body is maintained at the predetermined position. To do.

By providing the configuration according to claim 1, the water mobile control device according to the present invention can accurately specify a predetermined position (stationary position) even in a situation where radio waves are cut off, such as under a pier. Moreover, the amount of movement and the amount of rotation from that position can be accurately grasped, and the water moving body can be maintained at a predetermined position by controlling the propulsion means based on the information.

Further, in the present invention, by providing the configuration according to claim 2, rotation (roll, tilt) of the image due to shaking due to waves or the like is excluded, and more accurate control becomes possible.

Further, in the present invention, by providing the configuration according to claim 3, a predetermined position (stationary position) can be accurately specified even in a situation where radio waves are cut off, such as under a pier, and the position thereof. The amount of movement and the amount of rotation from the above can be accurately grasped, and by controlling the propulsion means based on the information, the water moving body can be maintained at a predetermined position.

(A) is a plan view showing an example of a water moving body provided with a water moving body control device according to the present invention, (b) is the same front view, and (c) is the same bottom view. It is a block diagram which shows the outline of the control device of the same as above. It is a side view which shows the usage mode of the above-mentioned water moving body. It is a flowchart which shows the process of the control method by the said control device.

Next, an embodiment of the water mobile body control device according to the present invention will be described with reference to the examples shown in FIGS. 1 to 4. In the figure, reference numeral 1 is a water moving body, reference numeral 2 is a water surface, and reference numeral 3 is a structure such as a pier.

The water moving body 1 includes a hull 4 having a circular shape in a plan view and a plurality of propulsion means 5, 5 ... Attached to the bottom of the ship, and a predetermined position is determined by controlling each propulsion means 5, 5 ... By a control device. Can be maintained. Reference numeral 6 in the figure is a power source for the propulsion means 5, 5 ... And the control device.

The water-moving body 1 is formed in a circular shape in a plan view in a stable state on the water, and although not shown in particular, it is provided with an outboard motor for movement and can move freely.

The propulsion means 5, 5 ... Are, for example, a thruster provided with a propulsion propeller that generates a propulsive force by rotation, and are a pair of thrusters that generate a clockwise propulsive force with respect to the hull 4 and a counterclockwise propulsive force. The pair of thrusters that generate the above-mentioned thrusters are arranged at different positions by 90 degrees from each other.

The rotation, stop, and output of each propulsion means 5 are independently controlled by the control device.

The control device includes a camera 7 installed on a moving body, a plurality of feature amount calculation means 8a to 8c having different algorithms for calculating feature amounts of images taken by the camera 7, and feature amount calculation means 8a to 8c. It is calculated by the conversion processing means 9 and the conversion processing means 9 that calculate the processing conversion matrix based on the feature amount calculated by 8c and calculate the movement amount ΔX, ΔY and the rotation amount Δr of the water moving body 1 by the processing conversion matrix. A control means 10 for controlling the water moving body 1 based on the moving amount ΔX, ΔY and the rotation amount Δr is provided so that the water moving body 1 maintains a predetermined position.

The camera 7 is installed on the hull 4 via the gimbal unit 11 with the optical axis directed in a predetermined direction.

As shown in FIG. 1, the gimbal unit 11 has a gimbal mechanism that rotatably supports the camera 7 in the horizontal direction and the vertical direction, a gimbal control means that controls the gimbal mechanism, and a gimbal control means that detects the swing of the camera 7 (not shown). A swing detecting means including a sensor is provided, and the orientation of the camera 7 is automatically maintained in a desired direction.

As shown in FIG. 2, the feature amount calculation means 8a to 8c, the conversion processing means 9, and the control means 10 are configured by the computer equipment 12, and by executing various programs, the processes necessary for control are sequentially executed. It has become like.

The feature amount calculation means 8a to 8c appropriately select and use three methods from image processing methods consisting of different algorithms such as ORB, BRISK, KAZE, and A-KAZE, and use each feature amount in the image captured by the camera 7. The feature points are extracted by the calculation means 8a to 8c, and the feature amount of the feature points is calculated and recorded at any time from the start of control.

The conversion processing means 9 calculates the homography matrix (processing conversion matrix) H using three or more corresponding points of the feature amounts calculated by the feature amount calculation means 8a to 8c.

尚、ｓはホモグラフィー行列のスケールリングに基づく係数、Ｈはホモグラフィー行列である。 Specifically, assuming that any coordinates on the initial image are (X1, Y1,1) and the coordinates on the moving image are (X2, Y2,1), both coordinates have the following relationship.

In addition, s is a coefficient based on the scale ring of the homography matrix, and H is the homography matrix.

このため、以下の式の逆行列が得られれば、Ｈを算出することができる。

Then, the coordinates of any three points a, b, and c on the initial image are set to (X1a, Y1a), (X1b, Y1b), and (X1c, Y1c), and the coordinates of the three points on the moving image are set to (X2a, Y1c). Assuming Y2a), (X2b, Y2b), (X2c, Y2c), for example, both coordinates are expressed by the following equations.

Therefore, H can be calculated if the inverse matrix of the following equation is obtained.

尚、ｈ１１、ｈ１２、ｈ２１、ｈ２２は回転項、ｈ１３、ｈ２３は移動項、ｈ３１、ｈ３２は台形状変換項である。 Further, the homography matrix H is expressed by the following equation.

Note that h11, h12, h21, and h22 are rotation terms, h13 and h23 are movement terms, and h31 and h32 are trapezoidal conversion terms.

尚、ａは解像度に基づく係数である。 Therefore, if the result of the coordinate transformation is known, the homography matrix is calculated based on the equations 1 and 2, and the transformation processing means 9 determines the movement amounts ΔX and ΔY of the water moving body 1 once the homography matrix H is determined. It is calculated by the following formula.

Note that a is a coefficient based on the resolution.

Further, the rotation amount Δr of the water moving body is obtained by the following equation.

The control means 10 determines whether or not the difference between the closest values of the movement amounts ΔX and ΔY of the water moving body 1 calculated based on the feature amounts calculated by the feature amount calculation means 8a to 8c belongs to a predetermined range. It is equipped with a determination unit and a control value determination unit that calculates the average value of two movement amounts and rotation amounts that belong to a predetermined range. If the determination unit determines that the movement amount and rotation amount are within the predetermined range, the movement amount and rotation amount The water moving body is controlled based on the average value of, and when it is determined that it is out of the range, the control is not performed and the image is acquired again.

Next, a method of controlling the water moving body using such a control device will be described.

First, the water moving body 1 is moved, and as shown in FIG. 2, it is moved under the structure 3 such as a pier, and the ship is stopped at a predetermined position where the work is performed. Point the camera 7 at 3b and start shooting.

At that time, since the camera 7 is supported by the gimbal unit 11, the influence of shaking due to waves or the like is eliminated, and only the change in the image due to the movement of the water moving body 1 can be captured.

The control device extracts feature points at predetermined positions (initial positions) by feature amount calculation means 8a to 8c consisting of three different algorithms such as ORB, BRISK, KAZE, and A-KAZE, and extracts the feature amounts, respectively. Calculate and record (s4).

Further, the control device extracts feature points by feature amount calculation means 8a to 8c consisting of three different algorithms such as ORB, BRISK, KAZE, and A-KAZE based on images taken at any time, and determines the feature amount. Calculate each (s5).

Further, using the above equations 1 to 4, a homography matrix is calculated based on the feature amount at the initial position and the feature amount based on the image taken thereafter (s6), and the movement amounts ΔX and ΔY are rotated by this homography matrix. The quantity Δr is calculated (s7).

Then, the control means 10 compares the movement amounts ΔX and ΔY calculated by the three different feature amount calculation means 8a to 8c by the determination unit (s8), and the results of the two methods having the closest values among the three are compared. When the difference is within a predetermined range (for example, 1 cm), the average value of the movement amounts ΔX and ΔY and the rotation amount Δr within the predetermined range is calculated (s9) assuming that the error is small, and based on the average value. The propulsion means 5, 5 ... Are controlled to return the water moving body to its original position (s10).

On the other hand, if the difference between the results of the two methods having similar values among the three is larger than a predetermined range (for example, 1 cm), it is determined that the error is large, a new image is acquired, and the image is used as the basis. Feature points are extracted by feature amount calculation means 8a to 8c consisting of three different algorithms such as ORB, BRISK, KAZE, and A-KAZE, the feature amounts are calculated, and the above steps 5 to s8 are repeated.

The water-moving body control device configured in this way eliminates errors due to image processing by repeating the process of s5 to s10, accurately grasps the amount of movement from the initial position, and based on that, moves the water-moving body. Since it is controlled, the water moving body can be maintained in an accurate predetermined position.

Further, when the water moving body 1 is moved, the process of s3 to s10 is repeated at the moved position.

The feature amount calculation means 8a to 8c are not limited to the above-mentioned ORB, BRISK, KAZE, and A-KAZE, and the feature amount calculation means 8a to 8c based on other algorithms may be used. The feature amount calculation means 8a to 8c to be used are not limited to three, and a plurality of feature amount calculation means 8a to 8c may be used.

Further, in the above-described embodiment, an example in which a circular boat is used as the hull 4 has been described, but the mode of the hull 4 is not limited to this, and a general boat, a raft, or the like may be used.

1 Water moving body 2 Water surface 3 Structure (pier)
4 Hull 5 Propulsion means (thruster)
6 Power supply 7 Cameras 8a to 8c Feature amount calculation means 9 Conversion processing means 10 Control means 11 Gimbal unit 12 Computer equipment

Claims (3)

In a water moving body control device for a water moving body having a plurality of propulsion means to maintain a predetermined position.
The camera installed on the water mobile body and
A plurality of feature amount calculation means having different algorithms for calculating the feature amount of the image taken by the camera, and
A conversion processing means that calculates a processing conversion matrix based on the feature amount calculated by each of the feature amount calculating means, and calculates the moving amount and the rotation amount of the water moving body by the processing conversion matrix.
A control means for controlling the plurality of propulsion means based on the movement amount and the rotation amount calculated by the conversion processing means is provided.
The control means is a determination unit for determining whether the difference between the closest values of the movement amount or the rotation amount of the water moving body calculated based on the feature amount calculated by each feature amount calculation means belongs to a predetermined range. And a control value determining unit that calculates the average value of the two movement amounts and the rotation amounts belonging to the predetermined range, and controls the plurality of propulsion means based on the average value of the movement amount and the rotation amount. A water-moving body control device, characterized in that the water-moving body is maintained in the predetermined position. A gimbal mechanism that rotatably supports the camera in the horizontal direction and the vertical direction, a gimbal control means that controls the gimbal mechanism, and a swing detection means that detects the swing of the camera are provided, and the orientation of the camera is set. The water moving body control device according to claim 1, wherein the water moving body control device is automatically maintained in a desired direction. In a method of controlling a water-moving body for maintaining a water-moving body having a plurality of propulsion means in a predetermined position.
The feature amount of the image taken by the camera installed on the water moving body is calculated by a plurality of feature amount calculation means having different algorithms.
After calculating the processing transformation matrix based on the calculated feature amount and calculating the moving amount and the rotation amount of the water moving body by the processing transformation matrix,
It is determined whether the difference between the closest values of the movement amount or the rotation amount of the water moving body calculated based on the feature amount calculated by each feature amount calculation means belongs to the predetermined range, and within the predetermined range. It is characterized in that the average value of the two moving amounts and the rotating amounts to which the two belong is calculated, the plurality of propulsion means are controlled based on the average value of the moving amount and the rotating amount, and the water moving body is maintained at the predetermined position. How to control a moving body on the water.

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