JPH0228095A - Underwater robot - Google Patents

Abstract

PURPOSE:To obtain an underwater robot performing follow-up action with movement of a mother ship by controlling a thruster and a propulsion part being based on information from a reception part, receiving a signal from the mother ship, and an obstacle detecting sensor. CONSTITUTION:An underwater robot 1 is constituted of a robot main unit 2, reception part 4 receiving a signal from a mother ship, obstacle detecting sensor 5, thruster 7, propulsion part 8 and a control mechanism 10 or the like controlling the thruster 7 and the propulsion part 8 being based on information from the reception part 4 and the obstacle detecting sensor 5. Accordingly, the signal from the mother ship 3 is received by the reception part 4, because the thruster 7 and the propulsion part 8 are controlled by the control mechanism 10, the underwater robot 1 performs follow-up action with movement of the mother ship 3, and the water in a water area to be desired for observation can be observed by the underwater robot 1. While the underwater robot 1, even when it detects an obstacle in the water, automatically avoids the obstacle by the obstacle detecting sensor.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is an unmanned underwater robot in which a navigating mother ship and an underwater robot are connected by a cable or the like,
This relates to an underwater robot that is used to observe underwater (including underwater) conditions by navigating underwater following the navigation of a mother ship while receiving signals from the mother ship.

[Conventional technology]

Traditionally, in relatively shallow waters such as ports and fishing reefs, when observing the bottom of the sea, a manned submersible with built-in imaging equipment such as a television camera or a still camera, or a submersible connected to the mother ship by cable etc. have been used. An unmanned robot was operated from the sea. In particular, unmanned cable robots are rapidly spreading worldwide due to their economic efficiency and safety. For example, underwater inspection robot j described in Japanese Patent Application Laid-Open No. 61-200089 is known.

In such conventional cable-type underwater robots, the diving device is suspended by cables, etc., and this cable functions as a power cable to a device that electrically controls the movement of the diving device underwater, and It also functions as a transmission cable for electrically transmitting observation results to workers on the ground, and has the characteristics of a composite cable.

In addition, towed underwater research robots without power are
The mother ship carried out an underwater survey while towing an underwater robot.

[Problem that the invention seeks to solve]

However, with the above-mentioned manned submersible, there is a risk that human life may be at stake in the event of an accident, and there are also problems such as the inability to conduct underwater observations for long periods of time due to the health of the people on board the submersible. , is not used favorably.

In addition, with the above-mentioned underwater robot with a cable, it is difficult to control the movement of the underwater robot on the ground, and observation and investigation tasks such as not knowing the top and bottom, or not knowing where it is at all, are difficult. was quite difficult. A case where such difficulty in operating an underwater robot becomes completely fatal is, for example, when investigating or observing a wide ocean area for a long period of time. For such applications,
Conventional underwater robots are of little use.

There are towed underwater robots that do not have power to survey wide ocean areas for long periods of time, but when conducting surveys in ports etc., it is important to accurately understand the positional relationship of underwater robots, and it is necessary to do so. This poses a serious problem in terms of having to operate from the sea and investigate narrow areas of the ocean floor in detail. In other words, manual control is impossible because it has no thrust.

This invention was devised in view of the above-mentioned problems and to completely solve them. ), and even though it is an unmanned underwater robot, it can receive signals from the mother ship, follow the mother ship's navigation, navigate freely underwater, and avoid underwater obstacles. The purpose of the present invention is to provide an underwater robot that can automatically avoid such problems, travel over a wide range of relatively shallow sea areas, and observe and investigate underwater conditions while maintaining an accurate positional relationship with a mother ship.

[Means for solving problems]

In order to achieve the above objects, the present invention provides an unmanned underwater robot that has a power transmission line for supplying power from the water and a communication line for information exchange between the water and the water. a receiving unit that receives signals from a mother ship to detect relative positions; an obstacle detection sensor that detects underwater obstacles; a thruster that adjusts the inclination of the underwater robot; and a propulsion unit that moves the underwater robot. Equipped with at least a control mechanism that controls the thruster and the propulsion section based on information from the receiving section and the obstacle detection sensor,
It consists of a configuration that controls it to follow the mother ship.

Here, as a preferred aspect of the underwater robot, when the receiving section of the underwater robot cannot receive a signal from the mother ship to detect the relative position between the mother ship and the underwater robot, the underwater robot sends a warning signal to the mother ship via a communication line. Preferably, the underwater robot is equipped with a warning mechanism for transmitting a warning or an emergency levitation mechanism for surfacing the underwater robot.

[Effect]

The present invention having the above configuration operates as follows.

In other words, transport the underwater robot to the water area you want to observe,
After the underwater robot is submerged in the water, the mother ship sends a signal to the underwater robot so that the relative position between the mother ship and the underwater robot can be constantly detected. Signals from the mother ship are received by the receiver, and the information is sent to the control mechanism.

The control mechanism drives the thruster and the propulsion section as appropriate depending on the content of the information, causing the underwater robot to follow the movement of the mother ship and submerge. Since the underwater robot follows the movement of the mother ship, the mother ship can guide the underwater robot into the water area that it wishes to observe by simply navigating the area where it has been observed, for example. Then, the underwater situation is observed using, for example, observation equipment equipped on the submerged underwater robot.

During this time, if an underwater obstacle is encountered, the obstacle is detected by the obstacle detection sensor, the information is sent to the control mechanism, and the thruster and propulsion unit are activated as appropriate depending on the content of the information. For example, the underwater situation can be observed while being driven to automatically avoid underwater obstacles.

〔Example〕

Hereinafter, the present invention will be described in more detail based on embodiments shown in the drawings.

Here, FIG. 1 is a schematic diagram showing a command unit provided in a mother ship and an underwater robot underwater, FIG. 2 is a plan view of the underwater robot, and FIG. 3 is a side view of the underwater robot.

In the figure, an underwater robot 1 consisting of an unmanned cable includes a robot body 2 consisting of a pressure-resistant container, and a receiving unit 4 that receives signals from the mother ship 3 on the water surface in order to detect the relative position between the mother ship 3 and the underwater robot l. , an obstacle detection sensor 5 for detecting underwater obstacles, an observation device 6 for observing the underwater situation, a thruster 7 for adjusting the inclination of the underwater robot 1, and a propulsion unit for moving the underwater robot 1. 8, a cable 9 connecting the underwater robot sotoe and the mother ship 3, and a control mechanism IO that controls the thruster 7 and propulsion section 8 based on information from the receiving section 4 and obstacle detection sensor 5. .

The robot main body 2, which is a pressure-resistant container, is made of, for example, FRP (reinforced plastic) material with a small specific gravity, and is hollow inside. The upper surface of the robot body 2 is equipped with a receiving section 4 that receives signals from the mother ship 3 on the water surface.

The receiving unit 4 includes, for example, an ultrasonic receiver, and two pairs of ultrasonic receivers are arranged to detect the relative position from the mother ship 3 on the water surface. Therefore, the mother ship 3 is equipped with an ultrasonic transmitter 11 that informs the underwater robot 1 of its relative position with the mother ship 3.
is provided.

Further, the mother ship 3 is provided with an ultrasonic transmitter 11 that gives commands to the underwater robot 1 such as diving and surfacing. Furthermore, in order to confirm the direction of the underwater robot (1), a direction sensor (for example, a magnetic direction sensor) is built into the underwater robot (1) and the mother ship (3), and the information is sent from the robot (1) via a data cable (9). By determining the difference in orientation, the relative orientation of the underwater robot 1 with respect to the mother ship 3 can be calculated.

Now, considering the case where mother ship 3 is sailing at a constant speed,
A position signal constantly transmitted from the ultrasonic transmitter 11 of the mother ship 3 propagates underwater (or under the sea) and is transmitted to the receiving section 4 of the underwater robot 7) 1. Two pairs of ultrasonic receivers are arranged in the underwater robot 1 as shown in FIG. 4, and the relative position from the mother ship 3 is calculated from the data from the water depth sensor and the output of the ultrasonic receivers. Assuming that the propagation speed of ultrasonic waves is constant, the difference in arrival time causes the underwater robot to
This is to calculate the angle of elevation between the plane and the mother ship 3, which can be found using a simple trigonometric formula.

The configuration of the receiving section 4 of this ultrasonic receiver is as shown in FIG. That is, the output θ from the ultrasound receiver. , θ, is amplified by an amplifier 14, a time difference output signal of θ8θ is extracted by an arrival time difference signal output circuit 15, and an f/v converter 16 (frequency-voltage conversion) outputs an analog voltage corresponding to the time width. , an analog voltage corresponding to the elevation angle between the underwater robot 1 and the mother ship 3 is output. This analog voltage is converted into a digital signal by the A/D converter 17 and the data is sent to the CPU circuit 18.

There are two systems for this processing, and the data from both are combined to provide the underwater robot 1 and mother ship 3 in the same x and y plane as the water surface.
This is to calculate the relative position of .

On the front side of the robot body 2, there are installed, for example, in Figs.
An obstacle detection sensor 5 as shown in D) is provided. The obstacle detection sensor 5 detects obstacles using ultrasonic waves. This is to attach an assault element to the front part of the underwater robot 1 at a certain predetermined angle, and the black circle mark in the figure is an ultrasonic sensor (ultrasonic vibrator). FIG. 6 is a conceptual diagram for explaining the corners of the sensor installation; the actual installation locations are the upper and lower parts of the head dome (9), and it is better to install the sensor separately at the upper and lower parts of the head dome 9 to avoid interference such as shadows.

The obstacle detection sensor 5 is located at the lower side 5-1 and the front diagonally lower side 5-2.
, front 5-3, front diagonally upper 5-4, right diagonally lower 5-5,
It consists of six ultrasonic transducers 5-6 diagonally downward to the left.

As shown in Figure 6(D), the lower part 5-1 and the diagonally lower front part 5
-2 and the obstacle detection sensor 5 installed on the bottom (
θ is calculated based on the angle θ between the horizontal plane (or the seabed) and the output from the obstacle detection sensors provided diagonally below the front 5-2 and in the front 5-3.

Here, the command angle is θ - kl θ1 + k, θ2 (choose the optimal value for kt, kt). The underwater robot 1 sends angle data according to the topography of the underwater surface (or seabed surface) to the control mechanism 10. As a result, the angle of the propulsion section 8 is controlled, making it possible to navigate along the topography of the water bottom while maintaining a constant distance from the water bottom.

In addition, when the obstacle detection sensors 5 such as the front 5-3 and the left and right sensors 5-4 and 5-5 detect an obstacle, the information is immediately sent to the control mechanism 10 installed inside the robot body 2. to make a right turn, left turn, or climb to avoid obstacles.

All such judgment criteria are built into the control program converted into firmware of the control mechanism IO, and the underwater robot 1 automatically performs these judgments, avoidance actions, etc.

The observation equipment 6 for observing the underwater situation is built into the robot body 2, and is also installed inside the head dome 19 provided on the front side of the robot body 2. Reference numeral 19 has a hemispherical shape and is made of, for example, transparent pressure-resistant glass. For example, a television camera or a still camera is used as the observation device 6, but an ultrasonic transmitting/receiving device may be used as the observation device 6, especially when three-dimensional observation is required.

The contents observed by this observation equipment 6 are sent to the mother ship 3 via a cable 9, so that the state of the ocean floor can be observed in real time.

Therefore, when you want to observe a certain point in detail,
It also has the advantage of being able to stop the mother ship 3 and switch to manual control of the underwater robot I, allowing detailed observations of narrow spots to be performed immediately, as was done with conventional underwater robots.

At the rear of the robot body 2, tail wings are provided in the shape of a cross, and a thruster 7 for adjusting the inclination of the underwater robot I is also provided. The thruster 7 is formed on the rear side of the robot body 2. The thruster 7 functions to adjust the trim angle of the underwater robot I. Thruster-7 is set to I? by controller f1110. I will be controlled.

In addition, on the left and right sides of the robot body 2, there are
A pair of propulsion parts 8 are equipped to move the l. The inside of each propulsion section 8 is protected by a cover having a substantially warhead shape, and a motor, gears, etc. are housed inside the cover.

Further, a propulsion screw is provided at the rear of the propulsion section 8,
A cylindrical duct is formed on the circumferential side of the screw.

The propulsion section 8 is rotatably attached to the side surface of the robot body 2, and can be rotated horizontally and vertically with respect to the robot body 2.

Therefore, by changing the angle of the ttL advance section 8 with respect to the robot body 2 and controlling the rotation speed of the motor of the propulsion section 8,
It is possible to freely move in three-dimensional space.

These propulsion units 8 are controlled by a controller j1410.

The cable 9 has one end connected to the upper surface side of the robot body 2 and the other end connected to the mother ship 3.

A cable 9 connects power to the mother ship 3 to drive the propulsion section 8.
A power transmission line for supplying power from the underwater robot 1 to the underwater robot 1, and a communication line for exchanging information between the mother ship 3 and the underwater robot 1 are integrated into one composite body.

The outer periphery of the cable 9 is coated with a protective material.

Further, the cable 9 has such strength that it cannot be easily broken by the tension generated when the underwater robot 1 is pulled away from the mother ship 3 by a tidal current or the like. Furthermore, the cable 9 has twisting and bending properties that can accommodate underwater movement of the underwater robot 1.

In order to make the above system more complete, it is important to maintain the posture of the underwater robot l. No matter how precisely the ultrasonic waves informing the relative position from the mother ship 3 are received, the propulsion sensor detects the propulsion, and the obstacle detection sensor 5 detects obstacles, the underwater robot 1 must maintain its posture horizontally. It is a prerequisite that the However, since it is impossible to maintain a horizontal posture (tilt at 0) at all times, the underwater robot l has built-in tilt sensors in the heel and trim directions, and the relative position with respect to the mother ship 3 is determined by the output of these tilt sensors. Information, distance to obstacles, bottom (
It is a system that calculates corrections for angles with the seabed (or seabed). It is also possible to continuously hold data from these ultrasonic sensors and investigate the topography of the underwater (or ocean floor).

The above control mechanism IO includes a receiving unit 4 that receives a signal from the mother ship 3 to detect the relative position between the mother ship 3 and the underwater robot 1, and an obstacle detection sensor 5 that detects underwater obstacles. Based on this information, the thruster 7 and propulsion section 8 of the underwater robot 1 are controlled, and a programmed computer is built in. The control mechanism 10 can be controlled by signals from the mother ship 3 via the communication line of the cable 9 as necessary, and can also handle correction calculations for attitude control of the underwater robot 1. . This control mechanism 10 is built into the robot body 2.

In addition, in the underwater robot sotoe, when the receiving unit 4 cannot receive a signal emitted from the mother ship 3 to detect the relative position between the mother ship 3 and the underwater robot 1, the underwater robot 1 is sent to the mother ship 3 via the communication line of the cable 9. Either or both of a warning mechanism that sends a warning signal and an emergency levitation mechanism that controls the propulsion section 8 upward to cause the underwater robot 1 to emerge urgently is incorporated.

The emergency levitation mechanism is a mechanism that is automatically activated when the receiving section 4 cannot receive a signal from the mother ship 3 for a certain period of time.

These warning mechanisms and emergency ascent mechanisms are controlled by the above control mechanism IO.
Although it is incorporated into the system, it may also be provided as an independent mechanism.

Note that bottom landing legs 20 are provided at the bottom of the robot body 2.

Next, the effects based on the configuration of the above embodiment will be explained below.

First, move the underwater robot to the water area (or sea area) you want to observe.
transport. The underwater robot 1 is placed on a mother ship 3 and transported to a predetermined water area. The underwater robot 1 carried by the mother ship 3 to a predetermined water area is lowered from the mother ship 3 to the water surface (or sea surface).

The underwater robot 1 lowered to the water surface is underwater (or underwater)
It is designed and manufactured in advance so that the specific gravity is approximately the same as that of . The underwater robot 1 starts diving with the propulsion unit 8 facing downward. And the head dome 19 of the underwater robot 1
While measuring the distance to the seabed with the obstacle detection sensor 5 installed below 5-1, when reaching a predetermined depth,
Complete the dive.

After reaching this state, the mother ship 3 sends a signal to the underwater robot l. The signal from the mother ship 3 is converted into an ultrasonic signal and then transmitted from an ultrasonic transmitter 11 provided in the mother ship 3. The ultrasonic waves transmitted from the ultrasonic transmitter 11 are received by the receiving unit 4, which is composed of two pairs of ultrasonic receivers of the underwater robot 1 floating in the water. Then, the signal received by the receiving unit 4 is analyzed by the method described above to detect the relative position of the underwater robot 1 with respect to the mother ship 3, and the information is sent to the control mechanism IO, and the computer of this control mechanism IO determines the relative position of the underwater robot 1. Based on that judgment, the underwater robot
-1's thruster 7 and propulsion unit 8 are controlled so that the underwater robot 1 follows the movement of the mother ship 3.

In this way, the mother ship 3 simply navigates the water area that you want to observe, and the underwater robot 1 uses the function of the underwater robot 1 that follows the movement of the mother ship 3 to navigate the water area that you want to observe.
The observation equipment 6 built into the head dome 19 of the underwater robot 1 observes the underwater situation, and the observation results are recorded in a recording device and sent to the mother ship via a cable 9 at the same time. 3 will be transmitted.

Furthermore, when the underwater robot 1 encounters an underwater obstacle while navigating underwater, the obstacle detection sensor 5 detects the obstacle. The front 53 and left and right 5-4 as shown in FIG.
When the obstacle detection sensor 5 such as 5-5 detects an obstacle, the information is immediately sent to the control mechanism 10 installed inside the robot body 2, and depending on the content of the information, the By driving the thruster 7 and the propulsion unit 8, a right turn, a left turn, or a climb is performed to avoid obstacles.

In addition, if the signal for detecting the relative position with the mother ship 3 suddenly stops for some reason, a warning mechanism is activated to quickly notify the mother ship 3 of this as a warning signal via the communication line of the cable 9. be able to. As a result, it is possible to instantly know when the underwater robot l cannot follow the mother ship 3, and to take subsequent measures quickly.For example, the underwater robot l can be controlled from the mother ship 3 via the communication line of the cable 9. The underwater robot 1 can be levitated by operating the machine mio.

Further, if this abnormal situation continues for a long time, the emergency levitation mechanism is activated and the underwater robot 1 automatically rises to the surface, making it possible to prevent trouble from occurring.

All such judgment criteria are built into the control program that is converted into firmware of the control mechanism 10, and the underwater robot 1 automatically performs these judgments and avoidance actions. This allows you to observe underwater conditions while automatically avoiding underwater obstacles.

When the underwater observation is finished and the underwater robot 1 is to be brought to the surface, the underwater robot 1 is brought to the surface by turning the propulsion section 8 upward.

It should be noted that this invention is not limited to the above embodiments, and it goes without saying that various modifications can be made without departing from the spirit of the invention.

〔Effect of the invention〕

As is clear from the above description, according to the underwater robot according to the present invention, the underwater robot that is submerged and the mother ship that navigates on the water surface are an unmanned underwater robot system that does not require any particularly difficult operations. It consists of

In other words, the mother ship simply navigates the area of water (or sea area) that it wants to observe, and the underwater robot automatically follows the mother ship and performs the observation. As described above, the underwater robot according to the present invention requires almost no troublesome mechanical operations and can freely navigate underwater, and has excellent characteristics not found in conventional cabled underwater robots.

Moreover, since it is unmanned, underwater observations can be carried out in a desired body of water without any danger, and with peace of mind.
Since there is no need to consider human health, it is possible to conduct observations over a wide area over a long period of time.

In addition, the underwater robot according to the present invention has an algorithm for its operation in response to various pre-assumed underwater (or seabed) terrain patterns, and can automatically respond to underwater obstacles. Therefore,
You don't have to worry about complicated operations.

Furthermore, if you want to observe details in a spot, you can switch to manual operation, which means you can stop the mother ship and freely operate it from the sea using a controller.

As described above, according to the present invention, it is possible to provide a high-performance underwater robot that is easy to use and highly safe.
Its contribution to industry is enormous.

[Brief explanation of the drawing]

The drawings show an embodiment of the underwater robot according to the present invention, in which FIG. 1 is a schematic diagram showing a command unit provided in a mother ship and an underwater robot underwater, FIG. 2 is a plan view of the underwater robot, and FIG. Figure 3 is a side view of the underwater robot, Figure 4 is a diagram explaining the correspondence between the two pairs of receivers provided on the underwater robot and the ultrasonic transmitter from the mother ship, and Figure 5 is a diagram showing the relationship between the mother ship and the underwater robot. A block diagram of the processing circuit for detecting the position, Figures 6 (A) to (D) are conceptual diagrams of the installation of the obstacle detection sensor, (A) is a plan view of the head dome, and (B) is the head dome. A front view of the dome, (C) a right side view of the head dome, and (D) a diagram for measuring topographical data of the water bottom. [Explanation of symbols] 1: Underwater robot 2: RoboSoto body 3: Mother ship
4: Receiving unit 5: Obstacle detection sensor 6: Observation equipment 7: Thruster
8; Propulsion unit 9: Cable 10: Control mechanism 11: Ultrasonic transmitter 14: Amplifier 15: Arrival time difference signal output circuit 16: F/V converter 17: A/D converter 18: C
PU circuit 19: Head dome 20: Legs for bottoming Patent applicant

Claims (1)

[Claims] 1. Detecting the relative position between a mother ship and an underwater robot in an unmanned underwater robot that has a power transmission line for supplying power from the water and a communication line for exchanging information between the water and the water. a receiving unit that receives signals from the mother ship; an obstacle detection sensor that detects obstacles in the water; a thruster that adjusts the inclination of the underwater robot; a propulsion unit that moves the underwater robot; An underwater robot characterized in that it is equipped with at least a control mechanism that controls the thruster and the propulsion section based on information from an object detection sensor, and is controlled to follow a mother ship. 2. The underwater robot is equipped with a warning mechanism that sends a warning signal to the mother ship via a communication line when the receiver cannot receive a signal from the mother ship to detect the relative position of the mother ship and the underwater robot. The underwater robot according to claim 1. 3. The underwater robot is equipped with an emergency levitation mechanism that causes the underwater robot to emerge when the receiver cannot receive a signal from the mother ship to detect the relative position between the mother ship and the underwater robot. underwater robot.