143 results about "Underwater light" patented technology

Disclosed is a disinfection lamp with an underwater light projection effect, comprising an upper lampshade, a lower lampshade, a lens lampshade and a tube for containing sustained release chlorine tablets, wherein a circuit board and a battery are arranged on the lens lampshade, a solar panel is mounted on the surface of the upper lampshade, a first light bead is arranged on the lower surface of the circuit board, a light diffuser is arranged at a position, corresponding to the first light bead, of a bottom of the lens lampshade, the first light bead is located in the light diffuser, and the lower lampshade is mounted at the bottom of the lens lampshade. The disinfection lamp can float on water, and the tube containing the sustained release chlorine tablets is immersed in water, such that a conventional water purification, sterilization and disinfection effect is realized.

The invention discloses an end-to-end underwater three-dimensional reconstruction method and system based on an underwater imaging model, and belongs to the technical field of underwater image processing. According to the method, deep learning pose estimation is combined with an underwater imaging model; firstly, a multi-frame underwater image sequence is collected as input, a deep neural network is constructed, and the network mainly comprises two core sub-modules: a pose estimation network; secondly, a three-dimensional reconstruction network is adopted, dense point cloud or voxel reconstruction is completed according to the predicted pose and image content, pose estimation and the three-dimensional reconstruction process are integrated in the same system, and overall joint optimization is achieved; and in combination with a self-adaptive underwater imaging model, modeling is performed on physical processes such as underwater illumination attenuation and scattering, so that the reality sense and the accuracy of a reconstruction result are improved. According to the method, high-quality three-dimensional reconstruction of images in a complex underwater environment is realized, and the method can be widely applied to ocean engineering, underwater robots, submarine topography surveying and mapping and underwater cultural relic protection.

Disclosed is a disinfection lamp with an underwater light projection effect, comprising an upper lampshade, a lower lampshade, a lens lampshade and a tube for containing sustained release chlorine tablets, wherein a circuit board and a battery are arranged on the lens lampshade, a solar panel is mounted on the surface of the upper lampshade, a first light bead is arranged on the lower surface of the circuit board, a light diffuser is arranged at a position, corresponding to the first light bead, of a bottom of the lens lampshade, the first light bead is located in the light diffuser, and the lower lampshade is mounted at the bottom of the lens lampshade. The disinfection lamp can float on water, and the tube containing the sustained release chlorine tablets is immersed in water, such that a conventional water purification, sterilization and disinfection effect is realized.

The invention discloses a monocular and binocular cooperative localization and mapping method and device for underwater refraction compensation, and the method comprises the steps: extracting checkerboard angular points, compensating an underwater light path through employing a two-time vector correction model based on a Snell law, and precisely calibrating the internal and external parameters of a binocular camera. According to the method, an underwater real light path is effectively restored, and calibration errors caused by medium refraction are remarkably reduced. Then epipolar correction is performed on the corrected left and right images, so that the geometric consistency of stereo matching is ensured; and finally, monocular and binocular poses are fused, and seven-degree-of-freedom similarity transformation global alignment is applied, so that the problem of monocular scale uncertainty is effectively solved, and high-precision and high-robustness three-dimensional mapping is realized by means of binocular real scale introduction. Key links such as camera pre-calibration, refraction compensation, image correction, monocular tracking, binocular depth measurement, scale alignment and the like are connected in series to form an integrated process, so that the underwater vision positioning and mapping precision is improved.

The invention provides an underwater target detection method and system based on deep learning. The method comprises the following steps: acquiring an underwater image sequence; depth information is generated based on the underwater image sequence, and boundary contours of different underwater objects are extracted through a deep learning algorithm in combination with the depth information; constructing a reflection mode of underwater light according to the surface roughness of various underwater objects, and then performing semantic division according to the reflection mode to obtain mask regions corresponding to different semantic levels of each image frame; for each image frame, determining texture direction features, determining main reflection directions of underwater light in different mask areas, and further determining semantic coordination degree of each mask area according to all the texture direction features and all the main reflection directions; and generating confidence semantic tags of different underwater objects in the underwater image sequence based on all semantic coordination degrees. By adopting the scheme provided by the invention, the anti-distortion detection can be performed on the underwater target under the interference of the underwater environment.

The invention discloses an underwater target identification and positioning method based on fusion of a physical model and deep learning, and belongs to the technical field of computer vision, and the method comprises the steps: carrying out the transmissivity estimation and physical restoration of a collected underwater monocular image according to an underwater light propagation model, and carrying out the image correction; key feature points are extracted, and high-quality matching point pairs are screened in combination with the joint similarity; further deriving a basic matrix through the high-quality matching point pairs meeting the epipolar geometric constraint relation, solving an essential matrix, and obtaining relative attitude parameters between the cameras in combination with weighted re-projection-LM optimization; and finally, refraction correction triangulation is carried out according to the Snell's law, pixel-level fusion is carried out after scale normalization and space alignment are carried out on the refraction correction triangulation and dense depth output by the MiDaS, three-dimensional space coordinates of the target are inverted, and high-precision recognition and positioning of the underwater target are achieved. The system is light in structure, efficient in calculation, suitable for being integrated on various underwater autonomous or remote control robot platforms and used for tasks such as target recognition, tracking and positioning.

The invention discloses an underwater high-speed three-dimensional measurement method based on stripe structured light, and relates to the technical field of underwater optical three-dimensional imaging, in an underwater operation scene of an FPP system, projecting a three-step phase shift sine stripe and a Gray code pattern to an object to be measured, and respectively calculating a wrapped phase 1, a wrapped phase 2 and an auxiliary order phase; analyzing the light intensity information received by the camera, and carrying out water body influence analysis in combination with an underwater light transmission model; the initial wrapped phase divides the order phase into a stable region and a non-stable region, the stable region is combined with the wrapped phase 1 to calculate a preliminary absolute phase, and the non-stable region is combined with the wrapped phase 2 to calculate an absolute phase through an island processing method. According to the method, a phase bisection complementary decoding strategy is adopted, a jump error region in an order phase is effectively identified and corrected by constructing complementary wrapped phase information, a wrong order phase is corrected by using a noise correction algorithm, and the measurement stability in a dynamic scene is remarkably improved.

The invention belongs to the technical field of maintenance illumination in a high-radiation environment of a nuclear power station, aims to solve the problems that illumination in the underwater environment under high radiation is insufficient and a traditional underwater lamp is inconvenient to use flexibly due to the too large size, and discloses a portable illumination device for maintenance illumination in the high-radiation environment of the nuclear power station. Comprising a strip-shaped floodlight assembly, a column-shaped floodlight assembly or a round floodlight assembly which are installed on a long-rod connecting rod, an LED lamp is arranged in a main body frame of the strip-shaped floodlight assembly, a floodlight reflecting tile and the LED lamp are correspondingly arranged, the column-shaped floodlight assembly is provided with a floodlight cavity and a front cover, and floodlight thermoswitch pressing plates are installed in the floodlight cavity and the front cover. An LED lamp is installed on the floodlight thermoswitch pressing plate, an LED lamp is arranged in a circular cavity of the circular spotlight assembly, and a spotlight reflecting tile is installed in front of the LED lamp. According to the invention, portable and effective illumination can be provided for the underwater operation environment in the maintenance activity of the nuclear power station in the high-radiation environment.

The invention discloses an AUV (Autonomous Underwater Vehicle) pose detection method and system based on underwater light vision, a medium and a program product, and belongs to the field of underwater robots. The method comprises the following steps: judging the turbidity of a water body by analyzing the blue channel characteristics of an image, dynamically adjusting the graying weight, and generating a preprocessed image by adopting blue channel enhancement; constructing triple constraint conditions of contour number, spacing and area, and combining a variable step size strategy to realize threshold adaptive optimization; wick pixel coordinates are extracted through contour circularity screening, a leak detection grading mechanism is established, and feature point compensation is performed based on exponential smoothing filtering prediction and historical frame data; and finally, performing P3P pose calculation according to confidence levels. The method can be suitable for various water areas, blue light source feature extraction and feature point matching tasks are well achieved, and the stability and accuracy of AUV pose detection are improved.

The invention provides an underwater cleaning robot with an electric adjusting washing disc, the robot is directly driven by a propeller to slide on a netting to realize cleaning, and the robot is composed of a frame, a propeller, a high-pressure washing disc, a washing disc control mechanism, a floating body, an underwater camera, an underwater camera, an underwater lamp, a waterproof sealed cabin and the like. According to the technical scheme, the robot is driven by the propellers, slides on the net, is simple and reliable in structure and is matched with the passive front guide wheels, when the robot encounters obstacles such as net ropes and trusses on the net, the obstacle crossing performance of the robot can be remarkably improved, and therefore the net washing efficiency is improved. And through the rotating mechanism driven by the underwater motor, the deflection angle of each row of washing discs can be independently adjusted, the washing discs are more attached to the netting, and the cleaning effect of the netting near the obstacle is improved.

The utility model relates to a kind of pool underwater lamps, including lamp body, waterproof joint, adjusting rubber ring and locking ring.Lamp body includes shell, circuit device with lamp pearl sealed in shell by pouring glue and lampshade installed in the front of shell by sealing ring, and fastener is arranged on the tail of shell;Glue ring groove and external thread are arranged on the outer wall of the front of shell;The fastener is connected to realize the electrically connectable connection of lamp by waterproof joint;Adjusting rubber ring is sleeved in the glue ring groove of shell, locking taper is arranged on the outer wall thereof;Internal thread is arranged in the central hole of locking ring, and lamp installation locking flange and multiple notch grooves are arranged on the outer wall of inner end;Notch groove divides lamp installation locking flange into multiple arc-shaped elastic straining flanges;When the internal thread of locking ring is screwed on the external thread of shell and is screwed in, under the action of adjusting rubber ring, elastic straining flange is straining outward.The utility model has more reasonable structure, is installed quickly and easily, more widely, and is applicable to the pipe of certain size of different national standards.

The utility model discloses a kind of irradiation resistance underwater light supplementing lamps, belong to underwater light supplementing lamp technical field, solve the irradiation range of the underwater light supplementing lamp of multiple lamp body becomes larger, but condensing effect is obviously worse, so cannot condensing clear irradiation certain object, affect the visibility when actual underwater operation problem. Including circular arc lamp panel, the lamp body of several fixed connections in lamp panel, and the light-reflecting plate of the rotation connection in lamp panel outer circle, several light-reflecting plate can be relative lamp panel flip, several light-reflecting plate synchronous rotation setting. The utility model uses, when needing large range illumination, traction electromagnet pulls connection rope, makes light-reflecting plate deflect, torsional spring accumulates elastic potential energy, turns wire pole and prevents connection rope scratch breakage. When needing condensing irradiation, traction electromagnet is powered off, release connection rope, torsional spring releases potential energy and drives light-reflecting plate reverse deflection, forms spotlight cover, makes light concentration, clear irradiation object, does not affect underwater operation visibility.

The utility model discloses a straight line outgoing type underwater lamp belt, which comprises waterproof boxes, a lamp body and an FPC (flexible printed circuit) board, the waterproof boxes are mounted at two ends of the lamp body, the FPC board is positioned in the lamp body and extends along the length direction of a bottom plate, the two ends of the FPC board and the lamp body extend into the waterproof boxes, each waterproof box comprises a base and a cover plate, and the cover plate is mounted on the base. A fixing plate is arranged on the base, the bottom face of the end, extending into the waterproof box, of the lamp body is attached to and fixed to the fixing plate, the bottom end, the left end and the right end of the cover plate are open, and the opening in the bottom end of the cover plate is in sealed connection with the base. The left end opening and the right end opening of the cover plate are respectively enclosed with the cover plate to form a first socket and a second socket, the first socket is used for the end part of the lamp body to extend into the cover plate, and the second socket is provided with a waterproof wire assembly. According to the utility model, the current access of the lamp body is safer, and the overall waterproof sealing performance is good.

The invention discloses an underwater light source detection method and system based on a dark channel prior defogging algorithm, a medium and a program product, and belongs to the field of underwater image processing. Firstly, a dark channel of an underwater light source image is calculated through a dark channel prior algorithm, and a depth map is constructed by combining an ambient light coefficient and a medium transmissivity coefficient; and performing feature extraction on the depth map by using a lamplight mask generation function, screening an effective light source area through double criteria of contour length and circularity in combination with OpenCV contour detection and a morphological screening mechanism, calculating a contour centroid coordinate based on an image moment algorithm, and performing pose estimation of the underwater robot. Compared with the prior art, the method can quickly and accurately calculate the position of the underwater light source, and is higher in adaptive capacity and higher in accuracy compared with normal morphological feature extraction.

An underwater luminaire and a method for manufacturing the underwater luminaire are provided. The method includes assembling a light fixture into a housing, without a fastener disposed in the light fixture, where an opening of the fastener is in fluid communication with an open volume in the housing. The housing is placed in a vacuum chamber and the vacuum chamber is evacuated to remove air from the open volume of the housing. A dry gas is introduced into the vacuum chamber to fill the open volume in the housing, and a fastener is mounted in the lamp to seal the open volume.

The invention discloses an underwater two-way optical transmission simulation method based on a turbulent phase screen and vector Monte Carlo, and the method comprises the steps: building a three-dimensional coordinate system, and initializing parameters; generating a multi-layer turbulence phase screen; generating a random rough surface to simulate a target rough surface; sequentially judging whether the photons intersect with the phase screen, arrive at a target surface and arrive at a receiving surface; if the photon intersects with the phase screen, calculating an intersection coordinate, and updating the photon coordinate and direction; if not, whether a target surface is reached is judged, and if the target surface is reached, a return transmission process is triggered; if the photon does not arrive at the target surface, judging whether the photon arrives at a receiving surface, and if the photon arrives at the receiving surface, recording information of the current photon on the receiving surface; if the receiving surface is not reached, updating photon information, and judging the survival state of photons; and repeating the process until the photons arrive at the receiving surface or the weight is lower than a survival threshold value, and accumulating the number of the received photons and a polarization state statistical result. According to the invention, a theoretical basis is provided for underwater light transmission and optical communication experiment research of blue-green polarized light.

The invention provides a weak signal denoising method for an underwater light curtain dynamic target based on CEEMD combined permutation entropy and kurtosis, and belongs to the technical field of nonlinear non-stationary weak signal denoising. The method comprises the following steps: firstly, carrying out CEEMD decomposition on a collected underwater light curtain signal to obtain IMF1i components, determining a boundary IMF1k by utilizing a maximum value of a second order difference value of each IMF1i permutation entropy, and recombining the components after the IMF1k to obtain a first denoising signal; the method comprises the following steps: firstly, carrying out first-time denoising on a signal to obtain a first-time denoising signal, secondly, carrying out EMD decomposition on the first-time denoising signal to obtain IMF2i components, calculating kurtosis values of the IMF2i, and finally, determining a boundary IMF2k through a sliding T test method, and recombining the components after the IMF2k to obtain a final denoising signal. According to the non-linear non-stationary weak signal denoising method, denoising of the non-linear non-stationary weak signal is achieved through secondary denoising and introduction of a self-adaptive demarcation point selection method in each denoising, and the method is high in adaptability, high in robustness, wide in application range and low in calculation complexity and has a better denoising effect in a strong noise environment.

The present application provides an underwater target detection method and system based on dual complementary dynamic convolution. The method includes: obtaining light field distribution data of an underwater target through a photonic crystal sensing array, where the light field distribution data includes non-uniform scattering characteristics and spatial frequency domain distortion characteristics; using a dual complementary dynamic convolution operator to perform dual complementary coupling on the non-uniform scattering characteristics and the frequency domain response characteristics of the photonic crystal sensing to generate a dynamic convolution kernel weight distribution; using the dynamic convolution kernel weight distribution to perform spatio-temporal degradation suppression on the spatial frequency domain distortion characteristics, and combining the temporal correlation characteristics of the pulse network to generate an anti-interference enhanced feature sequence; combining the anti-interference enhanced feature sequence to perform positioning and classification on the underwater target, and eliminating the error of the underwater light transmission path during the positioning and classification process to generate a positioning and classification result of the underwater target. The present application improves the accuracy and robustness of underwater target detection.

The application discloses an end-to-end underwater three-dimensional reconstruction method and system based on an underwater imaging model, and belongs to the technical field of underwater image processing.The application combines deep learning pose estimation with an underwater imaging model; firstly, a plurality of underwater image sequences are collected as input to construct a deep neural network, the network mainly comprises two core sub-modules: one is a pose estimation network; and the other is a three-dimensional reconstruction network, according to the predicted pose and image content, dense point cloud or voxel reconstruction is completed, the pose estimation and the three-dimensional reconstruction process are integrated in the same system to realize overall joint optimization; and the adaptive underwater imaging model is combined to model the physical processes such as underwater light attenuation and scattering, so that the realism and accuracy of the reconstruction result are improved.The application realizes high-quality three-dimensional reconstruction of images in a complex underwater environment, and can be widely applied to ocean engineering, underwater robots, seabed topographic mapping and underwater cultural relic protection.

The utility model discloses a split type LED underwater lamp, belongs to the technical field of LED underwater lamps, and solves the problems that when an underwater motor is controlled on the ground, the underwater motor can not receive signals due to the problem of water environment, and finally the condition that the motor has no feedback is influenced. Comprising a mounting shaft, a rotating seat capable of coaxially rotating relative to the mounting shaft and arranged at the lower end of the mounting shaft, connecting seats fixedly connected to the two sides of the rotating seat, a lamp holder hinged between the connecting seats on the two sides, and a lamp body fixedly connected to the lamp holder. The underwater lamp is fixed through the mounting shaft, the buoy is put to enable the wireless receiving module to float on the liquid level, receives wireless remote control signals and transmits the wireless remote control signals to the microcontroller, the controller generates PWM signals and direction level, the upper servo motor and the lower servo motor are driven through the double-H-bridge chip, the position and the angle of the lamp body are adjusted, and the buoy and the signal transmission line ensure that the underwater lamp can receive water surface signals. And the position and angle adjustment of the underwater LED lamp body can be wirelessly and remotely controlled by a user.

The invention relates to the technical field of underwater guidance, in particular to a self-adaptive exposure method for an underwater guidance recovery task, which is used for solving the problems of light spot overexposure, underexposure or insufficient contrast and the like caused by dynamic change of ambient light, water body scattering interference and target distance adjustment in an underwater environment in the existing exposure control method. According to the method, parameter convergence in an initial deployment stage and dynamic adjustment in a conventional operation stage are combined, statistical characteristics and connected domain information of a grayscale image are analyzed in real time, a multi-dimensional error term model is constructed to adjust camera exposure parameters, and clear imaging of an underwater light source target is achieved. According to the method, external sensor data is not needed, full-process self-adaption from cold start to stable operation can be completed only by depending on image features, different water quality, distance and illumination conditions can be adapted, optimal exposure parameters can be adapted in real time, and the real-time and robustness requirements of underwater guide recovery are met.

An underwater light including a programmable controller and a replaceable light-emitting diode (LED) printed circuit board assembly (PCBA) is provided. The light includes a controller PCBA in communication with the LED PCBA, and a connector for connecting the controller PCBA to the LED PCBA. An optically-transparent potting compound encapsulates the LED PCBA, and the LED PCBA can be safely replaced by removing a rear housing of the underwater light.

The present application relates to the field of eutrophication lake water ecological restoration, and discloses a device and system for improving underwater light conditions of a lake. Natural light on the water surface is introduced into the underwater area near the device through refraction and reflection by using a light path system, effectively improving the underwater light intensity. A wave dissipation system is arranged below the light path system to prevent disturbance of the water body and sediments by small waves, to a certain extent, reducing the influence of sediments and resuspension on water transparency, and further improving the underwater light conditions. The light path system, the wave dissipation system and the underwater fixing system are sequentially fixed and connected from top to bottom, and the height of the light path system and the wave dissipation system is adjusted through the underwater fixing system with the rise and fall of the water surface, improving the applicability of the device. The device has the characteristics of simple structure, convenient operation, good performance, easy installation and recycling, etc. It can effectively reduce the adverse effects of insufficient underwater light of the lake and wave disturbance on the growth of submerged plants.

The present application relates to a kind of underwater lighting lamp assembly for microalgae culture, further relates to the photobioreactor comprising using the underwater lighting lamp assembly.The underwater lighting lamp assembly of the present application can realize 360 ° light source layout, and also can integrate stirring and aeration device, realize the illumination, stirring and aeration of photobioreactor and other functions.The underwater lighting lamp assembly of the present application can promptly take away the heat generated by lamp, reduce the temperature of lamp tube, reduce the influence of high temperature on light emitting and its service life, also can reduce the heat transfer of lamp tube heat to microalgae culture solution, reduce the temperature rise of microalgae culture system.The hyperboloid stirring paddle and its paddle face gas distribution hole used, mixing is uniform, gas-liquid contact is sufficient, reduce the damage of stirring shear to algal cell, and stirring energy consumption is low.In addition, the underwater lamp assembly of the present application is simple in structure, can be directly applied to large microalgae culture container, form photobioreactor, and easily remove, scale expansion and component replacement.

The invention provides an underwater near-field sensing method and system based on a mechanical scanning sonar and an optical camera, and the method comprises the steps: obtaining echo data of the mechanical scanning sonar, and carrying out the preprocessing of the echo data, and obtaining sonar image data; after sonar image data is processed, a near-field acoustic boundary is obtained by combining near-field environment acoustic reflection propagation characteristics, and a real near-field boundary is further obtained; acquiring an optical image, and acquiring a near-field optical enhancement image based on an underwater light propagation model compensation and weight fusion image enhancement method; and synchronizing and outputting the near-field acoustic boundary and the near-field optical enhancement image by using a timestamp. Different sensing modes of acoustics and optics are combined, sonar focuses on geometric boundary and scale measurement, optics provides visual details and textures through double-branch multi-scale fusion of underwater light propagation compensation and non-blind sharpening, two paths of information are clear in positioning and do not interfere with each other, the system can obtain the sensing ability of structure contours and texture details at the same time, and the accuracy of the system is improved. Therefore, the identifiability and integrity of the near-field environmental elements are improved.

The present invention discloses a method for real-time dynamic monitoring of the yield of large-scale cultivation of desert cyanobacteria, which comprises the following steps: cultivating multiple groups of cyanobacteria under multiple initial underwater light intensity conditions, recording the sample dry weights of the multiple groups of cyanobacteria at different time periods and the average underwater light intensity of the day, and constructing a calibration curve of the average underwater light intensity of the day - cyanobacteria sample dry weight therefrom; measuring the average underwater light intensity of the day under the photoperiod conditions in the target cyanobacteria culture pond, and realizing real-time dynamic monitoring of the cyanobacteria sample dry weight in the target cyanobacteria culture pond according to the average underwater light intensity of the day and the standard curve, so as to infer the cyanobacteria yield. Compared with the prior art, the advantages of the present invention include: 1) realizing real-time dynamic monitoring of the yield of desert cyanobacteria; 2) having a simple usage method and being easy to operate; 3) having low cost and high detection efficiency.

1. The name of the design product: underwater lamp. 2. The use of the design product: the design product is used for underwater lighting and decoration. 3. The design points of the design product: in shape. 4. The picture or photo that best shows the design points: perspective view 1.

1. Name of the designed product: underwater lamp (G1.5). 2. Use of the designed product: for underwater lighting. 3. Design points of the designed product: in shape. 4. Picture or photo best showing the design points: perspective view 1.

Systems and methods for monitoring, detecting, measuring, altering, optimizing, and / or modifying electrical power delivered to a power consuming device. The power consuming device can be a light, speakers, fans, motors, any household electronic appliance, or other power consuming device. Also disclosed are light assemblies including a first plurality of strings of red LED lights, a second plurality of strings of green LED lights, and a third plurality of strings of blue LED lights (e.g., SMD LEDs). The light assembly also includes a driver configured to intermittently supply power from a power source to the red LED lights, green LED lights, and blue LED lights. The light assembly also includes a housing to house the light assembly, the driver, the power source, and a controller.

The utility model discloses a kind of high radiation-tolerant underwater lamps, belong to underwater lamp technical field, solve when needing to the environment of different positions below water surface is clearly collected, then it needs to adjust the irradiation angle of underwater lamp, and ensure that the angle of underwater lamp cannot appear the situation of shaking due to the impact of water flow, otherwise it can cause the problem of influence to the environment collection below water surface. Including lamp shell, and a plurality of lamp bodies are set on lamp shell, the back of the lamp shell is fixedly connected with a set of hinged frame. When the utility model adjusts the angle of underwater lamp, traction electromagnet is powered off, elastic push-pull rod pushes away limit rod from tooth groove, friction strip is displaced under waterproof electric push rod control, the convex of friction sleeve and friction wheel increases friction coefficient, realizes that transmission ratio increases, friction wheel drives hinged frame and lamp body to rotate, completes angle adjustment. After adjustment, traction electromagnet is powered on, pull limit rod and embed tooth groove, fixed turntable, prevent underwater lamp from being affected by water flow and shaking.