Drifting machine

Abstract

The application discloses a kind of drift machines, the drift machine is applied to the pipeline in the existence of fluid flow, including main body and buoyancy body, buoyancy body generates buoyancy to balance part or all gravity of drift machine, drift machine rides fluid flow to realize drift machine moves along pipeline.The drift machine of the present application can directly utilize the flow of fluid in the pipeline to move along the pipeline, this scheme can separate the power mechanism such as flow generator from the main body equipment of drift machine, can greatly reduce the energy consumption of machine body, can make the main body equipment of drift machine be separated from power cable, be favorable to long distance work, and relative to prior art, the drift machine has no shape requirement, and does not need complex control algorithm and calculation hardware device, can greatly reduce control difficulty and reduce cost.

Description

Technical Field

[0001] This invention belongs to the field of pipeline inspection technology and relates to a drifting machine. Background Technology

[0002] There are numerous pipes in daily life and industrial production, such as air supply ducts for central air conditioning, chemical pipelines, and water supply / drainage pipes in factories. Internal inspection of these pipes is a crucial maintenance task. Through internal inspection, defects and malfunctions within the pipes can be detected promptly, facilitating preventative measures and timely replacement or repair. To this end, researchers have developed many pipe inspection robots.

[0003] CN202210833584.5 discloses a pipeline inspection robot. This robot moves by supporting itself on the pipe wall with multiple wheels. However, the robot's motion mechanism cannot navigate complex pipelines. For example, when a pipeline transitions from horizontal to vertical, the robot cannot enter the vertical section from the horizontal one, nor can it overcome gravity to crawl through the vertical section. Especially when the pipe wall is dusty or wet, the coefficient of friction between the wheels and the wall decreases, and the wheels cannot generate sufficient friction to balance the robot's own weight.

[0004] For pipelines containing water (e.g., large water conveyance pipelines in reservoirs, water conveyance ditches, etc.), researchers use underwater vehicles (UVs) for inspections inside the pipeline. Typically, UVs have two or more propellers; the relative motion between the propellers and the water generates propulsion, enabling movement within the pipeline. If the thrust is not well controlled while moving through the pipeline, the UV can crash into the walls, causing serious damage. To avoid such collisions, the thrust of the multiple propellers must be carefully controlled. In manual control, the operator visually observes and manipulates the UV. When visual observation is not possible, a camera at the front of the UV transmits images back to the operator, who then controls the vehicle based on these images. If the pipeline is very long (e.g., several kilometers), the UV cannot transmit images to the operator within the enclosed space, and the operator's control signals cannot reach the UV. In response to this situation, we have had to improve the autonomous mobility of underwater vehicles by adding a large number of sensors and using advanced intelligent control algorithms, while correspondingly increasing computing hardware resources. This has led to a significant increase in the manufacturing and research and development costs of underwater vehicles.

[0005] If the pipe contains water and the space inside is relatively spacious, an underwater glider can also be used for inspection. Underwater gliders are propelled by their own buoyancy. The glider first increases buoyancy to rise to a certain height, then decreases buoyancy, adjusting its center of gravity to the front. Under the influence of gravity, the nose tilts downwards, and it glides. During this descent, the relative movement between the glider's wings and the water creates a force exerted by the water on the wings, propelling the glider forward.

[0006] The three existing technologies mentioned above cannot be applied to long-distance pipelines and pipelines with complex structures because:

[0007] (1) Both wheel-driven pipeline inspection robots and underwater vehicles mount their power mechanisms (i.e., drive wheels and propellers) on the main body of the machine. To provide power to the power mechanism, we can install batteries on the main body of the machine. However, the battery capacity is limited, and if the pipeline is several kilometers or even tens of kilometers long, it is difficult for the battery to maintain an ultra-long-distance and ultra-long-term endurance. Carrying a large-capacity battery will also increase the burden on the robot. If cable power is used, the cable length must be the same as the pipeline length. Obviously, a long cable will bring great drag resistance. It is very impractical to have the machine drag a cable several kilometers long forward.

[0008] (2) Submersibles and underwater gliders utilize the relative motion between their structural components (propellers, wings, etc.) and the fluid within a pipe to generate thrust. This thrust must be controlled to regulate the machine's speed and direction of movement. Thrust control is costly, requiring motion sensors, complex control algorithms, and the microcomputers that run these algorithms. In pipes with fluid flow, the velocity of the fluid affects structural components such as propellers and wings, further increasing the cost and difficulty of control. Poor thrust control can lead to the machine colliding with the pipe wall, causing serious consequences. Summary of the Invention

[0009] The purpose of this invention is to address the shortcomings of existing technologies by providing a drifting machine that directly utilizes the flow of fluid for movement, which can significantly reduce the energy consumption of the machine itself. This machine can easily move along complex pipes, and the machine and the fluid are essentially relatively stationary, reducing the difficulty of machine control and also reducing manufacturing costs.

[0010] The technical solution adopted in this invention is as follows:

[0011] A rafting machine for use within a pipe in which fluid flows, comprising a main body and a buoyancy body that generates buoyancy to balance part or all of the weight of the rafting machine, the rafting machine moving along the pipe by riding the fluid flow.

[0012] Furthermore, in the above technical solution, the drifting machine further includes one or more flow generators, which are disposed at one or more ports of the pipe, and the flow generators cause the fluid inside the pipe to flow. Even further, one or more flow generators can be disposed at one or more ports of the pipe to change the original path of the fluid flow within the pipe.

[0013] Furthermore, the drifting machine may also include one or more blocking blocks, which are disposed at one or more ports of the pipe, preventing fluid in the pipe from flowing out from the corresponding port. Even further, one or more blocking blocks can be placed at one or more ports of the pipe, thereby altering the original path of fluid flow within the pipe.

[0014] Furthermore, the buoyancy of the buoyant body is adjustable.

[0015] Furthermore, the buoyancy of the buoyant body repeatedly changes between two states: "greater than the weight of the rafting machine" and "less than the weight of the rafting machine".

[0016] Furthermore, the rafting machine also includes a height detection sensor for detecting the rafting machine's floating height in the fluid.

[0017] Furthermore, the center of gravity of the rafting machine does not coincide with the position of the buoyancy force.

[0018] Fluid flow within structures such as pipes often exhibits excellent directional characteristics, meaning the fluid invariably flows along the pipe. The drifting machine of this invention utilizes this characteristic, thereby greatly simplifying mechanical design and reducing control complexity. The drifting machine of this invention is easy to control, requires no power mechanism, and can easily move from the pipe inlet to the outlet. Compared to existing technologies, the drifting machine of this invention has the following advantages:

[0019] 1) The rafting machine in this invention moves along the pipe by relying on the flow of fluid within the pipe. A flow generator can be used at the inlet of the pipe to create fluid flow, or existing fluid flow within the pipe can be utilized. The rafting machine moves along the pipe by riding the fluid flow, a design concept completely different from existing technologies. Pipeline inspection robots and underwater vehicles mentioned in the background technology all have their power mechanisms mounted on the main body, while this invention separates the power mechanism from the main body. The power mechanism of this invention is either the flow generator or the fluid flow within the pipe. This design concept of separating the power mechanism from the main body solves the problem of power supply for the power mechanism within the pipe, while also achieving low noise for the main body. In this invention, the power mechanism (i.e., the flow generator) is located at the inlet of the pipe; the power supply cable does not need to enter the pipe. The power mechanism consumes electrical energy to overcome the frictional resistance between the fluid flow and the pipe wall. If the pipe is long, we only need to increase the power of the flow generator. Furthermore, because the flow generator is outside the pipe, increasing the power is easily achievable.

[0020] (2) The rafting machine of this invention moves forward along the flow of fluid within the pipe, and the speed of the rafting machine is essentially the same as the speed of the fluid flow. In other words, there is virtually no significant relative motion between the rafting machine and the fluid, which is equivalent to the rafting machine being suspended in a relatively still fluid. Therefore, the rafting machine does not require complex force and motion control, and thus does not require complex control algorithms or the hardware resources needed for such algorithms, greatly reducing the difficulty and cost of control. This is completely different from underwater submersibles and underwater gliders.

[0021] (3) Because the rafting machine and the fluid are almost relatively stationary, the rafting machine will not be subject to any additional force from the fluid, regardless of its shape. In other words, the shape design requirements for rafting machines are very low. In contrast, underwater vehicles and underwater gliders require streamlined shapes to reduce the impact of fluid flow on their movement. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of one structure of the rafting machine of the present invention;

[0023] Figure 2 This is a schematic diagram showing that the point of buoyancy of the rafting machine of the present invention does not coincide with the center of gravity;

[0024] Figure 3 Force analysis of the rafting machine in the case of a non-buoyant body;

[0025] Figure 4 A schematic diagram of fluid flow in a complex pipeline;

[0026] Figure 5A schematic diagram of the fluid flow trajectory is constructed to block the pipe port;

[0027] Figure 6 This is a schematic diagram showing areas of no flow within a complex pipeline.

[0028] Figure 7 A schematic diagram of constructing a fluid flow trajectory using a flow generator;

[0029] Figure 8 A schematic diagram showing a drifting machine in a pipe being blocked by an obstacle;

[0030] Figure 9 A schematic diagram of a buoyant body structure;

[0031] Figure 10 This is a schematic diagram illustrating the buoyancy fluctuations of a buoyant body.

[0032] Figure 11 A schematic diagram showing the fluctuating trajectory of a rafting machine as it moves through a pipe due to changes in buoyancy.

[0033] Figure 12 A schematic diagram of a drifting machine overcoming obstacles in a pipe;

[0034] Figure 13 This diagram illustrates different scenarios where the magnitude of buoyancy changes covers gravity.

[0035] In the diagram: 0. Drifting machine, 1. Main body, 2. Buoyancy body, 2-1. Cylinder, 2-2. Piston, 2-3. Screw motor, 2-4. Threaded hole bracket, 2-5. Threaded hole, 2-6. Screw, 3. Detection device, 4. Flow generator, 5. Block, P. Pipeline, F. Fluid flow, a. First protruding obstacle, b. Second protruding obstacle. Detailed Implementation

[0036] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific examples.

[0037] The rafting machine of the present invention is used in a pipe in which fluid flows, and includes a main body and a buoyancy body. The buoyancy body generates buoyancy to balance part or all of the weight of the rafting machine, and the rafting machine moves along the pipe by riding the fluid flow.

[0038] The term "pipeline" in this invention is used in a broad sense. It can refer to a closed pipe, a tubular space, an open water conveyance ditch, a tunnel, an air-raid shelter, a building corridor, etc.

[0039] The "fluid flow" mentioned in this invention can be the existing flow of fluid inside the pipe, or the flow generated at the port of the pipe using a flow generator.

[0040] Example 1

[0041] like Figure 1 The diagram illustrates a specific example of the rafting machine of the present invention. The rafting machine includes a main body, a buoyancy body, and a detection device. The main body is a circular, hollow shell. The buoyancy body and the detection device are installed inside the main body. The buoyancy body generates buoyancy in the fluid environment of the pipe; for example, when the pipe contains air, the buoyancy body can be a helium balloon with a density less than air; when the pipe contains water, the buoyancy body can be foam. The buoyancy balances the weight of the rafting machine, keeping it suspended in the fluid. The detection device is used to detect the internal conditions of the pipe, such as a camera or a material analysis instrument.

[0042] First, a flow generator is used at one end of the pipeline to create fluid flow within the pipeline. The flow generator can be a blower, exhaust fan, water pump, or suction pump, etc., which creates fluid flow within the pipeline by injecting or drawing fluid into it. Figure 1 The flow generator injects fluid into the pipe through the right port, creating a right-to-left flow. Alternatively, a flow generator can be placed at the left port to draw fluid from the pipe, also creating a right-to-left flow. The drifting machine is then placed into the pipe. It floats inside the pipe and drifts forward with the fluid flow until it reaches the pipe's outlet port. The drifting machine can be retrieved at the outlet port. As the drifting machine moves along the pipe, a detection device monitors the interior of the pipe and stores the data.

[0043] In this invention, the center of gravity and the point of application of buoyancy of the rafting machine can be designed to be non-coincident, so that the rafting machine can maintain a stable posture under the torque generated by gravity and buoyancy. Figure 2 As shown, when the machine's attitude deviates, the torque of buoyancy and gravity will readjust the rafting machine to an attitude where buoyancy and gravity are collinear.

[0044] A buoyant body balances the weight of the rafting machine, keeping it in a suspended state where the net force is zero. This helps reduce the friction between the rafting machine and the inner wall of the pipe. Without a buoyant body (such as...), Figure 3The rafting machine falls below the pipe under the influence of gravity. Contact pressure is generated between the rafting machine and the lower wall of the pipe, which further generates friction. This friction acts on the lower end of the rafting machine, hindering its movement and creating a velocity difference between the rafting machine and the fluid, resulting in relative motion. This relative motion leads to the interaction of forces between the rafting machine and the fluid. Therefore, under the influence of friction from the pipe wall and fluid forces, the rafting machine may roll or collide with the wall, both of which are detrimental to pipe inspection. This invention reduces or completely eliminates the influence of friction by incorporating a buoyancy body. The buoyancy of the buoyancy body can balance all or most of the weight of the rafting machine, thus reducing the contact pressure between the pipe wall and the rafting machine, thereby reducing friction. When the buoyancy of the buoyancy body equals the weight of the rafting machine, there is no contact pressure between the rafting machine and the pipe, and therefore no friction. Of course, if the buoyancy of the buoyant body is too great, the contact pressure and friction between the rafting machine and the upper wall of the pipe will also cause the rafting machine to roll during its forward movement. Therefore, it is essential to set up a buoyant body and to make the buoyancy as close as possible to or equal to the weight.

[0045] Example 2

[0046] In this embodiment, the rafting machine is used in a very complex pipe structure, such as Figure 4 As shown. The pipeline has multiple branches and five ports, labeled A, B, C, D, and E. To make the drifting machine perform inspections along the path from port A to port E, a flow generator is installed at port A, creating a flow pattern within the pipeline as shown. Figure 4 The fluid flow is shown. Clearly, the drifting machine starts from port A, and its inspection path is uncertain. Because the fluid flows simultaneously to ports B, C, D, and E, the drifting machine may drift to any of the pipe openings. In this example, blockages are installed at some of the ports. In this embodiment, blockages are installed at ports B, C, and D (e.g., ...). Figure 5 As shown in the figure, the block prevents the fluid from flowing out of ports B, C and D, thus creating a clear fluid flow trajectory, that is, the fluid flows from the fluid generator (port A) to port E.

[0047] Unexpected factors (such as fluid vortices, fluid disturbances, etc.) may cause the rafting machine to stall in stagnant areas, for example, during... Figure 6 This is the situation described above. To avoid this situation, a flow generator can be set up on another port, such as... Figure 7 As shown, a fluid flow is established that converges towards port E.

[0048] A key innovation of this invention is the use of fluid flow to establish complex yet defined motion paths, enabling the drifting robot to reliably move within complex pipe environments. Many existing technologies rely on manual operation to move robots through complex pipes; however, in long pipes, it's difficult for the robot to wirelessly transmit images or other signals to the operator. Cable transmission is also impractical, as cables severely hinder robot movement. Some existing technologies rely on numerous sensors and complex control algorithms to move the robot from the inlet to the outlet in complex pipes, but this is costly, and current artificial intelligence technology cannot achieve high reliability. Removing the robot from the pipe if it becomes uncontrollable is extremely difficult. In contrast, this invention establishes a clear fluid flow path within complex pipes, allowing the drifting robot to move along a designated path simply and reliably using the fluid flow. This eliminates the need for complex control algorithms, computational hardware, and sensors, thus reducing control complexity and manufacturing costs.

[0049] Example 3

[0050] When the buoyancy of the buoyant body equals the weight of the rafting machine, the machine can suspend itself in the fluid flow. However, achieving a balance between buoyancy and weight is very difficult. If the buoyancy is slightly greater than the weight, the rafting machine will remain above the pipe and move forward along the upper wall. If the buoyancy is slightly less than the weight, the rafting machine will remain below the pipe and move forward along the lower wall. This presents a problem... Figure 8 For example, when the rafting machine is above the pipe and encounters a protruding obstacle above the pipe, the rafting machine cannot pass over the obstacle, causing it to become stuck in the pipe. In this embodiment, this problem can be solved by changing the buoyancy of the buoyant body.

[0051] For example, when the fluid in the pipe is gas, the buoyancy body can be designed as an elastic airbag with a built-in heater. The airbag is filled with gas, and its density changes with temperature. Furthermore, the density of the fluid inside the airbag is less than the density of the fluid in the pipe; for example, if the fluid is air, the airbag could be filled with helium. When the heater is off, the buoyancy of the elastic airbag is slightly less than the weight of the rafting machine. When the heater is powered on, it generates heat, causing the gas inside the airbag to expand, increasing the airbag's volume and thus increasing buoyancy. When the heater is de-energized, the heat dissipates, the temperature of the gas inside the airbag decreases, the airbag's volume decreases, and thus the buoyancy decreases.

[0052] When the fluid inside the pipe is a liquid (such as water), the buoyancy body can be designed as follows: Figure 9The structure of the buoyancy body 2 includes a cylinder 2-1, a piston 2-2, a screw motor 2-3, and a threaded hole support 2-4. The cylinder 2-1 is a semi-enclosed cylindrical cavity. The piston 2-2 is inside the cylinder, and the piston and cylinder form a sealed cavity filled with gas. The screw motor 2-3 is mounted on the piston, and the threaded hole support 2-4 is mounted on the cylinder. The threaded hole support has a threaded hole 2-5 through which the screw 2-6 of the screw motor passes. The rotation of the screw motor drives the screw at its front end to rotate. Through the transmission of the screw and the threaded hole, the piston can move up and down. When the piston moves upward, the volume of the sealed cavity decreases, and the buoyancy of the buoyancy body in the water decreases. When the piston moves upward, the volume of the sealed cavity increases, and the buoyancy of the buoyancy body in the water increases.

[0053] There are many ways to change the buoyancy of a buoyant body. This example only provides a few feasible solutions, which are not intended to limit the ways to change the buoyancy.

[0054] Based on this, the buoyancy of the buoyant body is adjusted so that the buoyancy repeatedly changes between two states: "greater than the weight of the rafting machine" and "less than the weight of the rafting machine," such as... Figure 10 As shown. Therefore, the trajectory of the rafting machine within the pipe also fluctuates up and down accordingly. For example... Figure 11 As shown, when the buoyancy is less than the gravity, the rafting machine moves forward with the fluid while moving downward; when the buoyancy is greater than the gravity, the rafting machine moves forward with the fluid while moving upward.

[0055] This embodiment solves the problem of the rafting machine passing obstacles in a pipe by using a simple change in buoyancy. Figure 12 Taking a pipe as an example. When the rafting machine is blocked by the first protruding obstacle a in the pipe, when the buoyancy is less than the gravity, the rafting machine sinks and then passes under the obstacle on the back of the fluid. When the rafting machine is blocked by the second protruding obstacle b in the pipe, when the buoyancy is greater than the gravity, the rafting machine rises and then passes over the obstacle on the back of the fluid. This embodiment does not rely on any sensors, nor does it construct a complex control system or execute complex control algorithms; it achieves passage over obstacles simply by changing the buoyancy. The buoyancy of the buoyant body changes according to a set rule. The basic rule is that the buoyancy repeatedly changes between two states: "greater than gravity" and "less than gravity." For example, if the buoyant body is an elastic airbag with a built-in heater, the heater can be powered on and off at preset time intervals; the buoyant body is... Figure 9 With a piston cylinder structure, the piston can reciprocate at preset time intervals.

[0056] Besides solving the problem of overcoming obstacles, this embodiment also addresses another issue. Typically, for a rafting machine to suspend in fluid flow, the buoyancy of the buoyant body should equal its weight. However, achieving this perfect balance is extremely difficult. While counterweights can bring the buoyancy as close to gravity as possible, a slight difference will inevitably remain. If the buoyancy is slightly greater than the weight, this slight difference will keep the rafting machine above the pipe and in contact with its upper wall. If the buoyancy is slightly less than the weight, this slight difference will keep the rafting machine below the pipe and in contact with its lower wall. This contact creates pressure and friction, which can interfere with the rafting machine, preventing it from maintaining the same speed as the fluid flow and causing it to drift or roll. In this embodiment, the buoyancy of the buoyant body is adjusted to repeatedly change between two states: "greater than the rafting machine's weight" and "less than the rafting machine's weight." As long as the range of buoyancy variation covers the weight, the rafting machine's trajectory within the pipe can fluctuate up and down. For example, Figure 13 Three scenarios are shown: gravity in the middle of the buoyancy variation range, gravity in the lower half of the buoyancy variation range, and gravity in the upper half of the buoyancy variation range. All three scenarios achieve the goal of passing through protruding obstacles and reducing contact with the pipe wall. Clearly, "making the buoyancy variation range cover gravity" is easier to achieve than "making buoyancy equal to gravity."

[0057] According to the technical concept of the present invention, the above examples are based on the premise that the weight of the rafting machine remains basically constant. The buoyancy generated by the buoyancy body is adjusted to repeatedly change between two states: "greater than the weight of the rafting machine" and "less than the weight of the rafting machine". Similarly, under the same technical concept, the buoyancy generated by the buoyancy body of the rafting machine can also be based on the premise that the buoyancy generated by the buoyancy body of the rafting machine remains basically constant. The total weight of the rafting machine can be adjusted to repeatedly change between two states: "greater than the buoyancy" and "less than the buoyancy". For example, when the fluid in the pipe is liquid, a liquid storage tank can be set in the rafting machine, and the total weight of the rafting machine can be adjusted by pumping in or discharging the fluid.

[0058] Example 4

[0059] Based on Example 3, a height sensor is installed on the rafting machine to detect its floating height. If the fluid in the pipe is a liquid (e.g., water), a depth sensor can be selected to detect the floating height. If the fluid in the pipe is a gas (e.g., air), an ultrasonic ranging sensor can be installed at the top and / or bottom of the rafting machine to detect the distance between the rafting machine and the upper and / or lower walls of the pipe.

[0060] The floating height obtained using a height sensor can be used to construct a buoyancy control system for the buoyancy body. When the floating height continuously increases, it indicates that the rafting machine is rising; by reducing buoyancy, the machine can be prevented from rising further, avoiding contact with the upper wall of the pipe. Similarly, when the floating height continuously decreases, it indicates that the rafting machine is sinking; by increasing buoyancy, the machine can be prevented from sinking further, avoiding contact with the lower wall of the pipe.

[0061] The solution in this invention separates the power mechanism, such as the flow generator, from the main equipment of the rafting machine. This allows the main equipment of the rafting machine to be disconnected from the power cable. Components involved, such as motors and pumps used to regulate buoyancy or overall gravity, can be miniaturized or low-power models and powered by batteries. This invention represents a novel control approach that significantly reduces control costs and complexity compared to existing technologies.

[0062] The above description is only a partial embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A rafting machine, characterized in that, The rafting machine is used in a pipe where fluid flows. It includes a main body and a buoyancy body. The buoyancy body generates buoyancy to balance part or all of the weight of the rafting machine. The rafting machine moves along the pipe by riding the fluid flow. The buoyancy of the buoyancy body changes repeatedly between two states: "greater than the weight of the rafting machine" and "less than the weight of the rafting machine" according to a set rule.

2. The rafting machine according to claim 1, characterized in that, The drifting machine also includes one or more flow generators, which are located at one or more ports of the pipe and cause fluid to flow within the pipe.

3. The rafting machine according to claim 2, characterized in that, By placing one or more flow generators at one or more ports of the pipe, the original path of fluid flow within the pipe can be altered.

4. The rafting machine according to claim 1, characterized in that, The drifting machine also includes one or more plugs, which are located at one or more ports of the pipe and prevent fluid in the pipe from flowing out of the corresponding port.

5. The rafting machine according to claim 4, characterized in that, By placing one or more plugs at one or more ports of the pipe, the original path of fluid flow within the pipe is altered.

6. The rafting machine according to any one of claims 1-5, characterized in that, The center of gravity of the rafting machine does not coincide with the location where the buoyancy force acts.

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