JPH0457559B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is an unmanned and unroped underwater robot in which a navigating mother ship and an underwater robot are not connected by a cable or the like, and in which a navigating mother ship and an underwater robot are not connected by a cable or the like. The present invention relates to an unmanned, unroped underwater robot that follows a mother ship and is used, for example, to observe conditions underwater (including under the sea) by following the navigation of a mother ship while receiving signals.

[Conventional technology]

Conventionally, for example, when observing underwater conditions (including under the sea), either a manned submersible with built-in photographic equipment such as a television camera or a still camera, or an unmanned underwater vehicle connected to the mother ship with a cable or other cable. Robots were used.

In the case of a manned submersible, it is operated by a person on board the submersible, so it has the advantage of being able to navigate while avoiding underwater obstacles.

Further, as an unmanned underwater robot with a cable, for example, an ``underwater inspection robot'' described in Japanese Patent Application Laid-Open No. 61-200089 is known.

In this conventional underwater inspection robot, the diving device is suspended by a rope consisting of a cable, and this cable also functions as a power cable to a device that electrically controls the movement of the diving device underwater. It also functions as a transmission cable for electronically transmitting underwater observation results to ground control stations, and has the characteristics of a composite cable.

[Problem that the invention seeks to solve]

However, while the above-mentioned manned submersible has the above-mentioned advantages, in the event of an accident, it may immediately lead to a major accident that could endanger human life. It was unusable. Another problem was that, due to the health of the people on board the submersible, it was not possible to conduct underwater observations for long periods of time.

In addition, in the case of the above-mentioned underwater inspection robot, since there is a cable that serves multiple functions,
This cable becomes a hindrance, preventing the diving device from moving freely and reducing its performance, which poses a major problem in underwater observation.

Furthermore, when an underwater robot is connected to a mother ship using a cable or the like, accidents have occurred in which the cable becomes entangled with the screws of the mother ship or breaks.

As described above, the use of cables is a major cause of problems such as a decline in the motion performance of diving equipment (underwater robots) and problems such as cables getting entangled in screws or breaking. In particular, when the water flow is fast, there is a problem that the faster the water flow, the more serious the effect will be.

This invention was devised in view of the above-mentioned problems and to solve the problems.The purpose of this invention is to eliminate the disadvantages of manned or cabled systems, and to solve them while underwater. By having the robot follow the navigation of the mother ship while receiving signals from the mother ship, there is almost no need for cumbersome mechanical operations to make the underwater robot navigate underwater, and it can also automatically avoid underwater obstacles. To provide a mother ship following type unmanned and unroped underwater robot capable of obtaining a fully automatic mother ship following type underwater robot.

[Means for solving problems]

In order to achieve the above object, the present invention provides an unmanned and unroped underwater robot with a receiving section that receives signals from the mother ship to detect the relative position between the mother ship and the underwater robot, and a receiver that detects underwater obstacles. a thruster for adjusting the inclination of the underwater robot; a propulsion unit for moving the underwater robot; a diving and surfacing mechanism for submerging and surfacing the underwater robot; and a control mechanism for controlling the thruster and the propulsion unit. At least the receiving unit is comprised of two pairs of ultrasonic receivers arranged in orthogonal directions to detect the relative position from the mothership on the water surface, and the obstacle detection sensor is comprised of three or more. , the control mechanism controls the thruster and the propulsion section so that the underwater robot follows the navigating mother ship based on information from the receiving section, and controls the underwater robot ( or the seabed) with a horizontal plane, calculate a command angle from the angles it makes with a plurality of horizontal planes, and, based on this command angle, set the thruster so that the underwater robot avoids obstacles while navigating. and a configuration for controlling the propulsion section.

[Effect]

The present invention having the above configuration operates as follows.

That is, after transporting the underwater robot to the desired water area and submerging the underwater robot in that area, 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 mothership are received by a receiving section consisting of two pairs of ultrasonic receivers arranged orthogonally, and the information is sent to the control mechanism. The control mechanism drives the thruster and 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, for example, the area of water it has observed. Then, the underwater situation is observed using, for example, observation equipment equipped on the submersible underwater robot.

During this time, if an underwater obstacle is encountered, the obstacle detection sensor detects the obstacle, and the information is sent to the control mechanism, which drives the thruster and propulsion unit as appropriate depending on the content of the information. For example, the underwater situation can be observed while automatically avoiding 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 that follows a mother ship and is unmanned and unroped receives a signal from a mother ship 3 on the water surface in order to detect the relative position of the robot body 2 that is a pressure-resistant container, and the mother ship 3 and the underwater robot 1. an obstacle detection sensor 5 that detects underwater obstacles, and an observation device 6 that observes underwater conditions.
, a thruster 7 that adjusts the inclination of the underwater robot 1, and a propulsion unit 8 that moves the underwater robot 1.
The submersible robot 1 is comprised of a submergence and levitation mechanism 9 for submerging and surfacing the underwater robot 1, and a control mechanism 10 for controlling 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 low specific gravity, and is hollow inside. The upper surface of the robot body 2 is equipped with a receiving section 4 for receiving 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. For this reason, the mother ship 3 is provided with an ultrasonic transmitter 11 that informs the underwater robot 1 of its relative position with the mother ship 3.
Further, the mother ship 3 is provided with an ultrasonic transmitter 12 that gives commands to the underwater robot 1 such as diving and surfacing. Furthermore, it is equipped with a scanning sonar 13 for confirming the position of the underwater robot 1. The resonant frequency of each ultrasound transmitter is selected to minimize interference.

Now, considering the case where the mother ship 3 is sailing at a constant speed, the 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 1. can be conveyed to. Two pairs of ultrasonic receivers are arranged in the underwater robot 1 as shown in FIG. 4, that is, two pairs of ultrasonic receivers are arranged in orthogonal directions to detect the relative position from the mother ship on the water surface. The relative position from the mother ship 3 is calculated from the data from the water depth sensor and the output from the ultrasonic receiver. This is to calculate the elevation angle between the underwater robot 1 and the mother ship 3 based on the difference in arrival time, assuming that the propagation speed of the ultrasonic wave is constant, and is determined by a simple trigonometric formula.

The configuration of the receiving section 4 of this ultrasonic receiver is as shown in FIG. That is, after the outputs θ _x and θ _y from the ultrasonic receiver are amplified by the amplifier 14, the time difference output signal of θ _x −θ _y is extracted by the arrival time difference signal output circuit 15, and the analog voltage corresponding to the time width is output. The output f/v converter 16 (frequency-voltage conversion) outputs an analog voltage according to the elevation angle of the underwater robot 1 and the mother ship 3. 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 of this processing, and the data from both are combined to calculate the relative positions of the underwater robot 1 and the mother ship 3 in the same x and y plane as the water surface.

The underwater robot 1 is located on the front side of the robot body 2.
In order to be able to detect and automatically avoid obstacles on the bottom of the water (or the ocean floor) while navigating underwater, an obstacle detection sensor 5 as shown in FIGS. 6A to 6D is provided, for example. . The obstacle detection sensor 5 is designed to detect obstacles using ultrasonic waves. In this method, a transducer is attached to the front part of the underwater robot 1 at a predetermined angle, and the black circle mark in the figure is an ultrasonic sensor (ultrasonic transducer). FIG. 6 is a conceptual diagram for explaining the mounting angle of the sensor, and the actual mounting location is divided into upper and lower parts of the head dome 19 so that it does not interfere with photographing, etc.

The obstacle detection sensor 5 detects six ultrasonic waves: downward 5-1, diagonally lower front 5-2, front 5-3, diagonally upper front 5-4, diagonally lower right 5-5, and diagonally lower left 5-6. It consists of a vibrator.

As shown in FIG. 6D, the obstacle detection sensors 5 provided in the lower part 5-1 and the diagonally lower front part 5-2 detect the angle θ ₁ that the water bottom (or seabed) makes with the horizontal plane and the lower part in the diagonally front part 5-2. -2 and the output from the obstacle detection sensor provided in front 5-3 to calculate θ ₂ .

Here, as the command angle, θ=k ₁ θ ₁ +k ₂ θ ₂ (choose the optimal values for k ₁ and k ₂ ) The underwater robot 1 uses the angle data according to the topography of the underwater surface (or ocean floor) as the control mechanism. 10, the angle of the propulsion section 8 is controlled and it becomes 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 transmitted 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 based on the control mechanism 10.
The underwater robot 1 is designed to automatically perform these judgments, avoidance actions, etc., as it is built into the firmware control program.

The observation equipment 6 that observes the underwater situation is
It is built into the robot body 2 and installed inside a head dome 19 provided on the front side of the robot body 2. The head dome 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 device 6 are recorded in a recording device, and the contents that are taken out from inside the robot body 2 after recovering the underwater robot 1 and the contents observed by the observation device 6 are recorded. There is something that replaces the signal and transmits it to the mother ship 3 on the water surface. For the type that is transmitted to the mother ship 3,
The underwater robot 1 is provided with a transmitter, and the mother ship 3 is provided with a receiver.

At the rear of the robot body 2, a cross-shaped tail is provided, and a thruster 7 for adjusting the inclination of the underwater robot 1 is 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 1. The thruster 7 is controlled by a control mechanism 10.

Furthermore, a pair of propulsion parts 8 for moving the underwater robot 1 are installed on the left and right sides of the robot body 2. 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.
A screw for propulsion is provided at the rear of the propulsion section 8, and a cylindrical duct is formed on the circumferential surface of the screw.

The propulsion section 8 is rotatably attached to the side surface of the robot body 2 and can rotate horizontally and vertically with respect to the robot body 2.
Therefore, by changing the angle of the propulsion 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 a three-dimensional space. These propulsion units 8 are controlled by a control mechanism 10.

Further, inside the robot main body 2, a submersible and levitation mechanism 9 for submerging and surfacing the underwater robot 1 is provided. The diving and flotation mechanism 9 includes a compressed gas cylinder, a ballast tank 9a, and the like. The ballast tank 9a is formed on both left and right sides of the upper part of the robot body 2, and compressed air from a compressed gas cylinder is sent into the ballast tank 9a to discharge internal water or seawater, or water or seawater can be pumped into the ballast tank 9a. The underwater weight of the underwater robot 1 is adjusted by controlling the opening and closing of a solenoid valve for injection, thereby enabling the underwater robot 1 to dive and surface.

Control of the diving and surfacing mechanism 9 is performed by a control mechanism 10, and operations such as diving and surfacing of the underwater robot 1 are transmitted by ultrasonic waves from an ultrasonic transmitter 12 of the mother ship 3, but a separate timer mechanism etc. It is also possible to control the ascent start time. Further, when the underwater robot 1 is in a dangerous situation, it is automatically controlled to emerge in an emergency.

For example, when water leaks inside the robot body 2 of the underwater robot 1, the control mechanism 10 captures the outputs of water leakage sensors placed at various locations, and the robot is quickly brought to the surface. Furthermore, when an abnormality occurs in the thruster 7 or the motor of the propulsion section 8, for example, when a thermal relay functions to detect this situation, the robot is immediately brought to the surface.

In order to make the above system more complete, it is important to maintain the posture of the underwater robot 1. No matter how accurately the ultrasonic waves informing the relative position from the mother ship 3 can be received, the propulsion sensor can detect propulsion, and the obstacle detection sensor 5 can detect obstacles, it is difficult to maintain the underwater robot 1's posture horizontally. Being present is a prerequisite. However, since it is impossible to maintain a horizontal posture (tilt at 0) at all times, the underwater robot 1 has built-in tilt sensors in the heel and trim directions, and uses the output of these tilt sensors to obtain relative position information with the mother ship 3. This system calculates corrections for distances to obstacles, angles to the bottom (or seabed), etc. It is also possible to continuously hold data from these ultrasonic sensors and investigate the topography of the underwater (or ocean floor).

The control mechanism 10 described above receives information from 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. It controls the thruster 7 and propulsion unit 8 of the underwater robot 1 based on the above, and has a built-in programmed computer. The control mechanism 10 is also capable of controlling the submersion and levitation mechanism 9 and also handle correction calculations for attitude control of the underwater robot 1, as required. This control mechanism 10 is built into the robot body 2.

In addition, bottom landing legs 20 are provided at the bottom of the robot body 2.
is provided.

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

First, the underwater robot 1 is transported to a body of water (or a sea area) to be observed. The underwater robot 1 is placed on a mother ship 3 and transported to a predetermined water area. The underwater robot 1 is carried by the mother ship 3 to a predetermined water area and is lowered from the mother ship 3 to the water surface (or sea surface).

The underwater robot 1 lowered to the water surface is adjusted by injecting water or seawater into the ballast tank 9a of the submergence and flotation mechanism 9 so that the specific gravity is approximately the same as that of the water (or the sea). Then, the underwater robot 1 is separated from the mother ship 3 when the specific gravity of the underwater robot 1 becomes substantially the same as the specific gravity of the underwater (or underwater) environment.

In this case, the underwater robot 1 has the following information in advance:
Since a detachable weight is connected, the underwater robot 1 uses this weight to submerge. Below the head dome 19 of the underwater robot 1 5-
The underwater robot 1 moves to a predetermined depth while measuring the distance to the seabed with the obstacle detection sensor 5 installed in the underwater robot 1.
When the robot dives, the weight is separated from the underwater robot 1. The weight separation mechanism may be configured such that, for example, when the horizontal propulsion section 8 is rotated to a vertical position, a gripping mechanism that grips the weight automatically opens to separate the weight.

Since the underwater robot 1 from which the weight has been separated has a specific gravity approximately equal to that of the water (or the sea), its descent stops and it floats at that position.

After reaching such a state, a signal is sent from the mother ship 3 to the underwater robot 1. 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. Ultrasonic waves transmitted from the ultrasonic transmitter 11 are received by a receiving section 4 consisting 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 10.
Based on the judgment, the thruster 7 and propulsion unit 8 of the underwater robot 1 are
is controlled so that the underwater robot 1 follows the movement of the mother ship 3.

In this way, by simply having the mother ship 3 navigate the water area that you want to observe, the underwater robot 1 can use the function of the underwater robot 1 to follow the movement of the mother ship 3 to make the underwater robot 1 observe the water area that you want to observe. I can,
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 or transmitted to the mother ship 3.

Further, when the underwater robot 1 encounters an underwater obstacle while navigating underwater, the obstacle detection sensor 5
detects obstacles. Front 5 as shown in Figure 6
When the obstacle detection sensors 5 such as -3, 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. Depending on the content of the information, drive the thruster 7 and propulsion unit 8 as appropriate,
In order to avoid obstacles, a right turn, a left turn, or a climb is performed.

All such judgment criteria are based on the control mechanism 10.
The underwater robot 1 is designed to automatically perform these judgments, avoidance actions, etc., as it is built into the firmware control program. This allows you to observe underwater conditions while automatically avoiding underwater obstacles.

When the underwater observation is finished and the underwater robot 1 is brought to the surface, it is controlled via the control mechanism 10 by a signal from the ultrasonic transmitter 12 of the mother ship 3 or by operating a timer mechanism as necessary. Alternatively, the submergence and levitation mechanism 9 is operated directly. This operation is performed by sending compressed air from a compressed gas cylinder into the ballast tank 9a to discharge the water and seawater inside, thereby making the ballast tank 9a lighter, thereby making the specific gravity of the underwater robot 1 smaller than that of water (or seawater). The underwater robot 1 is made to float.

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 mother ship following type unmanned underwater robot according to the present invention, the mother ship simply navigates the water area (or ocean area) that it wants to observe, and the underwater robot automatically It is possible to almost eliminate the need for troublesome mechanical operations for making the underwater robot navigate underwater while following the mother ship.

In addition, the underwater robot according to the present invention has an algorithm for operating with respect to various pre-assumed underwater (or seabed) topography patterns, and is capable of detecting obstacles even in the water. Sensors detect obstacles, the information is sent to the control mechanism, and depending on the content of the information, the thrusters and propulsion unit are driven as appropriate to automatically avoid underwater obstacles. You don't have to worry about complicated operations.

In this way, due to the synergistic effect of the above two,
It is possible to obtain a fully automatic underwater robot that follows the mother ship, and it is possible to completely eliminate the need for troublesome mechanical operations for navigating the underwater robot underwater.

In addition, the receiving section consists of two pairs of ultrasonic receivers arranged in orthogonal directions in order to detect the relative position from the mothership on the water surface, so compared to one arranged in non-orthogonal directions, This makes calculations a little easier, reduces calculation errors, and allows underwater robots to more accurately detect relative positions, such as azimuth and depth, with respect to the navigating mother ship. Therefore, the error in tracking the underwater robot with respect to the mother ship is minimized, and the underwater robot can more reliably follow the navigating mother ship.

In addition, since there are no cables from the mother ship navigating on the water surface, there are various problems caused by cables, such as a decline in the maneuverability of underwater robots, and cables getting tangled with the mother ship's screws or breaking. This eliminates the inconvenience caused by In particular, it exhibits a diving function with excellent maneuverability even in areas with fast water flow, making it possible to observe underwater conditions, for example.

Furthermore, since it is unmanned, underwater observations can be carried out safely in any desired body of water without any danger, and long-term observations are also possible because there is no need to consider human health. Become.

As described above, the underwater robot according to the present invention can freely navigate underwater and has excellent characteristics not found in conventional cabled underwater robots.

Further, according to the present invention, it is possible to provide a high-performance mother ship-following unmanned underwater robot that is much easier to use and safer, and the contribution to the industry is enormous.

[Brief explanation of the drawing]

The drawings show an embodiment of an unmanned underwater robot that follows a mother ship according to the present invention. A plan view of the robot, 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 the mother ship. A block diagram of a processing circuit for detecting the relative position of the underwater robot and the underwater robot; Figures 6A to 6D are conceptual diagrams of the installation of the obstacle detection sensor; A is a plan view of the head dome; B
is a front view of the head dome, C is a right side view of the head dome, and D is a diagram for measuring topographical data of the water bottom. Explanation of symbols, 1...Underwater robot, 2...Robot main body, 3...Mother ship, 4...Receiving section, 5...Obstacle detection sensor, 6...Observation equipment, 7...Thruster, 8... Propulsion unit, 9... Submerged levitation mechanism, 9a
...Ballast tank, 10...Control mechanism, 11...
...Ultrasonic transmitter, 12... Ultrasonic transmitter, 13...
...Scanning sonar, 14...Amplifier, 15...
...Arrival time difference signal output circuit, 16...F/V converter, 17...A/D converter, 18...CPU
Circuit, 19... Head dome, 20... Legs for bottoming.

Claims (1)

[Claims] 1. An unmanned underwater robot is equipped with a receiving unit that receives signals from the mother ship in order to detect the relative position between the mother ship and the underwater robot, an obstacle detection sensor that detects underwater obstacles, and an inclination of the underwater robot. The receiver is equipped with at least a thruster that adjusts the movement of the underwater robot, a propulsion unit that moves the underwater robot, a diving and surfacing mechanism that makes the underwater robot go under and rise, and a control mechanism that controls the thruster and the propulsion unit, and the receiving unit It consists of two pairs of ultrasonic receivers arranged in orthogonal directions to detect the relative position from the mother ship, the obstacle detection sensor consists of three or more, and the control mechanism receives information from the receiving section. Based on the above, the thruster and propulsion unit are controlled so that the underwater robot follows the navigating mother ship, and the angle that the water bottom (or ocean floor) makes with the horizontal plane is determined based on information from each of the two obstacle sensors. A command angle is calculated from the angles formed with the plurality of horizontal planes obtained, and based on the command angle, the thruster and the propulsion unit are controlled so that the underwater robot avoids obstacles while navigating. An unmanned underwater robot that follows the mother ship.