A ship rudder angle measuring system and method

Abstract

The application provides a ship rudder angle measuring system and method, the system comprising a reflecting block, a displacement sensor and a signal comprehensive processing module, wherein: the reflecting block is fixedly connected with a rudder shaft, and converts a physical rotation angle amount of the rudder shaft into a physical displacement amount of a reflecting surface of the reflecting block; the displacement sensor converts the physical displacement amount of the reflecting surface of the reflecting block into a displacement signal through reflecting information; and the signal comprehensive processing module collects the displacement signal converted by the displacement sensor in real time, performs calculation, and outputs a rudder angle signal. In the application, a rudder angle measuring point is located on the rudder shaft rather than a rudder machine hydraulic cylinder, there is no nonlinear relationship conversion in the rudder angle measuring process, the rudder angle measuring error is small and high in precision, the application has the characteristics of high-precision non-contact measurement and simple structure and low cost, and helps to improve the control precision and reliability of a ship steering closed-loop control system.

Description

Technical Field

[0001] This invention belongs to the field of ship maneuvering and control technology, and in particular relates to a ship rudder angle measurement system and method. Background Technology

[0002] Rudder angle generally refers to the angle of rotation of the rudder blade or rudder shaft of a ship. The measurement range of rudder angle is generally ≤±40°. Rudder angle measurement is an important part of the steering closed-loop control system. As the military's requirements for the accuracy of ship steering control systems are increasing, higher requirements are also being placed on the accuracy and precision of rudder angle measurement.

[0003] Existing rudder angle measurement technologies typically place the measurement point on the rudder gear hydraulic cylinder. They measure the linear stroke of the hydraulic cylinder piston using displacement sensors, magnetostrictive sensors, or mechanical linkages, then convert this linear stroke into rudder angle. This method is complex, costly, and because the measurement point is always the rudder gear hydraulic cylinder, it doesn't directly measure the rudder shaft or rudder blade angle. Furthermore, the rudder angle and the hydraulic cylinder piston stroke are not absolutely linearly related, resulting in insufficient measurement accuracy. Additionally, mechanical installation errors are unavoidable during rudder angle measurement device installation, affecting the measurement accuracy. Adjusting these errors mechanically through the installation position is difficult on ships and also fails to meet the required measurement accuracy. Summary of the Invention

[0004] In view of this, the present invention provides a ship rudder angle measurement system and method that at least solves some of the above-mentioned technical problems. The rudder angle measurement point is located on the rudder shaft rather than the rudder motor hydraulic cylinder. There is no nonlinear relationship transformation during the rudder angle measurement process. The rudder angle measurement error is small and the accuracy is high. It has the characteristics of high-precision non-contact measurement and simple structure and low cost.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, embodiments of the present invention provide a ship rudder angle measurement system, the system comprising: a reflector, a displacement sensor, and a signal processing module, wherein:

[0007] The reflector block is fixedly connected to the rudder shaft and is used to convert the physical rotation angle of the rudder shaft into the physical displacement of the reflector surface of the reflector block.

[0008] The displacement sensor is used to convert the physical displacement of the reflective surface of the reflective block into a displacement signal through reflection information;

[0009] The signal processing module is used to collect displacement signals converted by displacement sensors in real time, perform calculations, and output rudder angle signals.

[0010] Preferably, the reflector is a laser reflector adapted to the rudder shaft, and the reflective surface of the reflector is a helical curved surface, the height of which increases from the front end to the rear end.

[0011] Preferably, the displacement sensor is fixedly connected to the rudder shaft flange, and the displacement sensor is a laser displacement sensor with a linearity of 1µm and a maximum resolution of 0.1µm.

[0012] Preferably, the signal processing module is also used to acquire zeroing instructions and amplitude correction instructions, and to perform calculations based on the acquired displacement signals to output the corrected rudder angle signal.

[0013] Secondly, embodiments of the present invention also provide a method for measuring ship rudder angle, applied to the aforementioned ship rudder angle measurement system, to achieve non-contact, high-precision measurement of ship rudder angle. The method includes:

[0014] S1. The physical rotation angle of the rudder shaft is converted into the physical displacement of the reflective surface of the reflective block through the reflective block;

[0015] S2. Using a displacement sensor, the physical displacement of the reflective surface of the reflective block is converted into a displacement signal through reflection information;

[0016] S3. The displacement signal converted by the displacement sensor is collected in real time through the signal integration and processing module, calculated, and outputted as the rudder angle signal.

[0017] Preferably, in step S3, the signal processing module outputs a rudder angle signal, and the formula for calculating the rudder angle is:

[0018] θ=(Ya) / k

[0019] Where θ represents the rudder angle, Y represents the displacement of the measuring point on the reflector surface of the reflector block, a is the displacement of the measuring point on the reflector surface when θ = 0, and k is a fixed coefficient.

[0020] Preferably, when installation errors exist, the signal processing module acquires zeroing and amplitude correction commands, and calculates and outputs a corrected rudder angle signal based on the collected displacement signal. The rudder angle calculation formula is as follows:

[0021] θ=(Ya-Δa) / (k 1* k)

[0022] Where θ represents the rudder angle, Y represents the displacement of the measuring point on the reflector surface of the reflector block, a represents the displacement of the measuring point on the reflector surface when θ = 0, Δa represents the zero-position deviation value between the current state and the ideal state, k1 is the ratio of the amplitude deviation value between the current state and the ideal state, and k is a fixed coefficient.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects:

[0024] 1. This invention provides a ship rudder angle measurement system and method, which is simple and convenient to measure. The rudder angle measurement point is located on the rudder shaft rather than the rudder motor hydraulic cylinder. There is no nonlinear relationship transformation during the rudder angle measurement process, the rudder angle measurement error is small and the accuracy is high, and it has the characteristics of high-precision non-contact measurement.

[0025] 2. This invention is applicable to rudder shafts with different shaft diameters; the theoretical rudder angle measurement range can reach ±180°; for rudder angles with a measurement range ≤ ±40°, 4-redundancy measurement can be achieved within a 360° range.

[0026] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0027] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention, but do not constitute a limitation thereof; in the drawings:

[0030] Figure 1 This is a schematic diagram illustrating the measurement principle of a ship rudder angle measurement system provided in an embodiment of the present invention.

[0031] Figure 2 This is a schematic diagram showing the installation positions of the reflector and displacement sensor provided in an embodiment of the present invention.

[0032] Figure 3 This is a top view of the reflective block provided in an embodiment of the present invention.

[0033] Figure 4 This is a front view schematic diagram of the reflective block provided in an embodiment of the present invention.

[0034] Figure 5 This is a schematic diagram of the signal processing flow of the signal integration processing module provided in an embodiment of the present invention.

[0035] in, Figure 2In the middle: 1: reflector block; 2: displacement sensor; 3: rudder shaft; 4: rudder shaft flange; 5: rudder shaft connecting rod. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0037] In the description of this invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0038] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0039] Example 1:

[0040] Combination Figure 1 and Figure 2 As shown, this embodiment of the invention provides a ship rudder angle measurement system, which mainly includes three parts: a reflector block 1, a displacement sensor 2, and a signal processing module.

[0041] The following is a detailed introduction to each of the above parts and their working principles:

[0042] In this embodiment, the reflector block 1 is rigidly fixedly connected to the rudder shaft 3, and the specific installation position is as follows: Figure 2 As shown, the reflector block 1 is rigidly mounted on the rudder shaft 3 near the rudder shaft connecting rod 5. It rotates with the rudder shaft during operation, so the physical rotation angle of the rudder shaft can be converted into the physical displacement of the reflector surface of the reflector block.

[0043] In this embodiment, the reflector block 1 is preferably a laser reflector block, see [link to relevant documentation]. Figure 3 and Figure 4As shown, the reflective surface of the reflective block adopts a spiral curved surface design, and its reflective surface height extends and increases from the front end to the rear end.

[0044] Furthermore, such as Figure 2 As shown, in this embodiment, the displacement sensor 2 is fixedly connected to the rudder shaft flange 4 and does not rotate with the rudder shaft. Preferably, the displacement sensor 2 is a laser displacement sensor. The laser displacement sensor can accurately and non-contactly measure the position, displacement, and other changes of the measured object. Its measurement principle is divided into laser triangulation and laser echo analysis. In this embodiment, the laser triangulation method is used, which is suitable for high-precision, short-distance measurement. The highest linearity of the laser displacement sensor can reach 1µm, and the highest resolution can reach 0.1µm. The laser displacement sensor 2 measures the displacement information of the measuring point on the reflective surface of the reflector block 1 in real time. The measuring point on the reflective surface refers to the projection point of the laser emitted by the laser displacement sensor on the reflective surface. When the reflector block 1 rotates with the rudder shaft, the height of the measuring point on the reflective surface changes, and the displacement of the laser reflective surface measuring point from the laser displacement sensor changes. Therefore, the physical displacement of the reflective surface of the reflector block can be converted into a displacement signal through the reflection information.

[0045] See Figure 5 As shown, in this embodiment, the signal processing module is located in the host computer of the ship's control console. The signal processing module includes a real-time acquisition unit, a command acquisition unit, a signal processing unit, and a signal output unit. The real-time acquisition unit acquires the displacement signal converted by the displacement sensor in real time and transmits it to the signal processing unit for calculation. The signal output unit then outputs the rudder angle signal. When the rudder angle measuring device (reflector and displacement sensor) has installation errors or needs correction, the command acquisition unit obtains a one-click zeroing command and a one-click amplitude correction command. These commands, combined with the displacement signal of the laser reflector measurement point acquired by the real-time acquisition unit, are sent to the signal processing unit for calculation, thereby outputting the corrected rudder angle signal to ensure the accuracy of the rudder angle measurement.

[0046] Example 2:

[0047] This invention also provides a method for measuring ship rudder angle, applied to a ship rudder angle measurement system described in Embodiment 1 above, to achieve non-contact and accurate measurement of ship rudder angle. The method flow is as follows: Figure 1 As shown, the method includes:

[0048] S1. The physical rotation angle of the rudder shaft is converted into the physical displacement of the reflective surface of the reflective block through the reflective block;

[0049] S2. Using a displacement sensor, the physical displacement of the reflective surface of the reflective block is converted into a displacement signal through reflection information;

[0050] S3. The displacement signal converted by the displacement sensor is collected in real time through the signal integration and processing module, and the rudder angle signal is calculated and output.

[0051] In this embodiment, the relationship between the displacement increment (ΔY) of the reflector surface measurement point and the rudder shaft rotation angle increment (Δθ) is ΔY = kΔθ, where k is a fixed coefficient determined by the helical coefficient of the laser reflector surface. The relationship between the displacement (Y) of the reflector surface measurement point and the rudder shaft rotation angle (θ) is Y = a + k*θ, where the constant a is the displacement of the reflector surface measurement point when θ = 0.

[0052] The working principle of the signal integration and processing module is as follows: Figure 5 As shown, when the rudder angle measuring device is in an ideal state, the signal processing module calculates the rudder angle signal according to θ = (Ya) / k. When there is an installation error in the rudder angle measuring device, when a one-click rudder angle zeroing command is given at the new zero position, the signal processing module will calculate the zero position deviation value Δa between the current state and the ideal state. When a one-click rudder angle amplitude adjustment command is given at the new amplitude position, the signal processing module will calculate the amplitude deviation ratio k1 between the current state and the ideal state. Then, the displacement of the laser reflector measurement point Y = a + Δa + k 1* k*θ, the final output rudder angle θ=(Ya-Δa) / (k 1* k).

[0053] As described in the above embodiments, those skilled in the art will understand that the present invention provides a ship rudder angle measurement system and method. The laser reflector uses a helical curved surface design to convert the rudder shaft rotation angle into the displacement of the laser reflector. Relying on a high-precision triangulation laser displacement sensor, the displacement information of the laser reflector measurement point can be accurately measured over a short distance. Combined with zeroing and amplitude calibration signals, the signals are processed and converted by the signal processing module to achieve non-contact, accurate measurement of the rudder shaft rotation angle. In this invention, the signal processing module has the functions of acquiring displacement information from the laser displacement sensor, acquiring one-click zeroing and amplitude calibration command information, converting displacement information and zeroing / amplitude calibration information into rudder angle information, and outputting rudder angle information as analog or digital signals.

[0054] Compared with existing rudder angle measurement methods, the present invention has at least the following advantages:

[0055] The rudder angle measurement point is located on the rudder shaft rather than the rudder motor hydraulic cylinder; it is applicable to rudder shafts of different diameters; the theoretical rudder angle measurement range can reach ±180°; for rudder angles with a measurement range ≤ ±40°, quadruple redundancy measurement can be achieved within a 360° range; there is no nonlinear relationship transformation during rudder angle measurement; it features high-precision non-contact measurement. This invention can be applied to the field of ship handling and control, providing a new non-contact, high-precision, and redundant method for rudder angle measurement, thereby improving the control accuracy and reliability of ship steering closed-loop control systems.

[0056] The embodiments of the present invention have been described in detail above, and the principles and implementation methods of the present invention have been explained. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention.

[0057] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A ship rudder angle measurement system, characterized in that, The system includes: a reflector, a displacement sensor, and a signal processing module, wherein: The reflector block is fixedly connected to the rudder shaft and is used to convert the physical rotation angle of the rudder shaft into the physical displacement of the reflector surface of the reflector block; the reflector block is a laser reflector block adapted to the rudder shaft, and the reflector surface of the reflector block is a helical curved surface design, with the height of the reflector surface increasing from the front end to the rear end; The displacement sensor is used to convert the physical displacement of the reflective surface of the reflective block into a displacement signal through reflection information; the displacement sensor is fixedly connected to the rudder shaft flange, and the displacement sensor is a laser displacement sensor with a linearity of 1µm and a maximum resolution of 0.1µm. The signal processing module is used to collect displacement signals converted by displacement sensors in real time, perform calculations, and output rudder angle signals. The signal processing module is also used to acquire zeroing commands and amplitude correction commands, and perform calculations in conjunction with the collected displacement signals to output corrected rudder angle signals. The signal processing module outputs the rudder angle signal, and the rudder angle calculation formula is as follows: θ=(Ya) / k Where θ represents the rudder angle, Y represents the displacement of the measuring point on the reflector surface of the reflector block, a is the displacement of the measuring point on the reflector surface when θ=0, and k is a fixed coefficient. When installation errors exist, the signal processing module acquires zeroing and amplitude correction commands, and calculates and outputs a corrected rudder angle signal based on the collected displacement signal. The calculation formula is as follows: θ=(Ya-Δa) / (k 1* k) Where θ represents the rudder angle, Y represents the displacement of the measuring point on the reflector surface of the reflector block, a represents the displacement of the measuring point on the reflector surface when θ=0, Δa represents the zero-position deviation value between the current state and the ideal state, k1 is the ratio of the amplitude deviation value between the current state and the ideal state, and k is a fixed coefficient.

2. A method for measuring the rudder angle of a ship, characterized in that, By applying the ship rudder angle measurement system as described in claim 1, accurate measurement of ship rudder angle is achieved, the method comprising: S1. Convert the physical rotation angle of the rudder shaft into the physical displacement of the reflective surface of the reflective block through the reflective block; S2. Using a displacement sensor, the physical displacement of the reflective surface of the reflective block is converted into a displacement signal through reflection information; S3. The displacement signal converted by the displacement sensor is collected in real time through the signal processing module, and the rudder angle signal is output. In step S3, the signal processing module outputs the rudder angle signal, and the rudder angle calculation formula is: θ=(Ya) / k Where θ represents the rudder angle, Y represents the displacement of the measuring point on the reflector surface of the reflector block, a is the displacement of the measuring point on the reflector surface when θ=0, and k is a fixed coefficient. When installation errors exist, the signal processing module acquires zeroing and amplitude correction commands, and calculates and outputs a corrected rudder angle signal based on the collected displacement signal. The calculation formula is as follows: θ=(Ya-Δa) / (k 1* k) Where θ represents the rudder angle, Y represents the displacement of the measuring point on the reflector surface of the reflector block, a represents the displacement of the measuring point on the reflector surface when θ=0, Δa represents the zero-position deviation value between the current state and the ideal state, k1 is the ratio of the amplitude deviation value between the current state and the ideal state, and k is a fixed coefficient.

Images