Underwater robot and water entry detection method

Abstract

The underwater robot comprises a robot body, a water entry detection circuit and at least two motors are arranged on the robot body, an electrode is arranged on an output shaft of each motor, the water entry detection circuit is electrically connected with the electrodes, the water entry detection circuit comprises a conditioning circuit, and the conditioning circuit is electrically connected with the motors. The adjusting circuit comprises a first control end, a first conduction end and a second conduction end, and the first conduction end is electrically connected with a power supply; the signal amplification module comprises a first input end and a first feedback end; the connection module is electrically connected with the second conduction end and the first input end; and the main control chip is electrically connected with the first feedback end and the first control end, and the main control chip is used for controlling the underwater robot to operate according to a preset mode based on the voltage signal of the first feedback end.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater robots, and particularly to underwater robots and water entry detection methods. Background Art

[0002] With the continuous growth of ocean development and underwater operation requirements, underwater robots have been widely used in fields such as ocean exploration, underwater construction, and scientific research. In the actual application of underwater robots, water entry detection is a key technical link, and its accuracy directly affects the working efficiency and safety of underwater robots.

[0003] In the prior art, water entry detection of underwater robots is usually achieved by means of pressure sensors or photoelectric sensors. Among them, the pressure sensor determines whether the robot enters the water by detecting the change in water pressure. The photoelectric sensor determines the water entry state by detecting the change in light intensity.

[0004] However, the related technologies have the following deficiencies: the pressure sensor is easily affected by water flow disturbance, while the photoelectric sensor has poor detection effect under turbid water quality conditions and is easily interfered by impurities in the water, which will affect the accuracy and reliability of detection. Summary of the Invention

[0005] The main object of the present invention is to propose an underwater robot, aiming to solve the problem of low accuracy and reliability of water entry detection in related technologies.

[0006] To achieve the above object, the present invention proposes an underwater robot, including a robot body. An water entry detection circuit and at least two motors are provided on the robot body. An electrode is provided on the output shaft of each motor. The water entry detection circuit is electrically connected to the electrode. The water entry detection circuit includes:

[0007] A conditioning circuit, the conditioning circuit includes a first control end, a first conduction end and a second conduction end, and the first conduction end is electrically connected to a power supply;

[0008] A signal amplification module, the signal amplification module includes a first input end and a first feedback end;

[0009] A connection module, the connection module is electrically connected to the second conduction end and the first input end respectively;

[0010] A main control chip, the main control chip is electrically connected to the first feedback end and the first control end respectively. The main control chip is used to control the underwater robot to operate in a preset mode based on the voltage signal of the first feedback end.

[0011] In some embodiments, a protection circuit is further included. The protection circuit includes:

[0012] A first transient diode, one end of the first transient diode is electrically connected to the second conducting end, and the other end of the transient diode is grounded;

[0013] A second transient diode, one end of the second transient diode is electrically connected to the connection module and the first input terminal, and the other end of the second transient diode is grounded.

[0014] In some embodiments, the conditioning circuit includes:

[0015] A switching transistor, one conducting end of the switching transistor is electrically connected to a power supply, the other conducting end is electrically connected to the connection module through a first resistor, and the trigger end of the switching transistor is electrically connected to the first control terminal.

[0016] In some embodiments, the signal processing module includes:

[0017] An operational amplifier, the non-inverting input terminal of the operational amplifier is electrically connected to the first input terminal, and the output terminal is electrically connected to the first feedback terminal;

[0018] A low-pass filter, the low-pass filter is electrically connected between the first input terminal and the inverting input terminal of the operational amplifier for filtering the output voltage signal.

[0019] In some embodiments, the low-pass filter includes:

[0020] A first capacitor, one end of the first capacitor is electrically connected to the first input terminal, and the other end of the first capacitor is grounded;

[0021] A second capacitor, the second capacitor is connected to the first input terminal, and the other end of the second capacitor is electrically connected to the inverting input terminal of the operational amplifier;

[0022] A first resistor, one end of the first resistor is electrically connected to the inverting input terminal of the operational amplifier, and the other end of the first resistor is grounded.

[0023] In some embodiments, the underwater robot further includes:

[0024] A housing;

[0025] Motors, two of the motors are arranged side by side and spaced apart inside the housing, output shafts of the two motors penetrate the housing, and propellers are provided;

[0026] An environmental monitoring module, the environmental monitoring module is arranged in the housing for detecting the surrounding environment;

[0027] Wherein, the motors and the environmental detection module are electrically connected to the main control chip, and the main control chip controls the motors and the environmental monitoring module to work according to the voltage at the first feedback terminal.

[0028] The present invention further provides an underwater detection method, which is applied to an underwater robot. The underwater detection method includes:

[0029] Obtaining a reference resistance value between the motor shafts of the underwater robot;

[0030] Detecting a current resistance value between the motor shafts of the underwater robot;

[0031] Based on the comparison result between the current resistance value and the reference resistance value, determining the underwater state of the underwater robot;

[0032] In response to the underwater state, controlling the working mode of the underwater robot;

[0033] Monitoring the operating state of the underwater robot; and

[0034] In response to the operating state, triggering a preset control strategy.

[0035] In some embodiments, the step of detecting the current resistance value between the motor shafts of the underwater robot further includes:

[0036] Collecting a plurality of the current resistance values within a preset time window;

[0037] Calculating the mean and standard deviation of the plurality of current resistance values;

[0038] Based on the mean and the standard deviation, dynamically adjusting the range of the reference resistance value.

[0039] In some embodiments, the step of collecting a plurality of the current resistance values within a preset time window further includes:

[0040] Smoothing the plurality of current resistance values to eliminate noise interference.

[0041] In some embodiments, the step of monitoring the operating state includes:

[0042] Continuously detecting the resistance value between the motor shafts;

[0043] Based on the change trend of the resistance value between the motor shafts, determining whether there is an abnormal electrode contact in the underwater robot.

[0044] The beneficial effects of the technical solution of the present invention are as follows: Detection is achieved by setting electrodes on the motor output shaft of the underwater robot and electrically connecting the electrodes to the water entry detection circuit, avoiding detection blind spots and improving the accuracy of detection. Among them, the water entry detection circuit adopts a combined structure of a conditioning circuit, a signal amplification module, and a connection module, realizing precise acquisition and effective processing of the resistance signal between the electrodes, and significantly improving the stability and reliability of the detection signal. At the same time, through the electrical connection design of the main control chip with the first feedback end and the first control end, the system can quickly respond according to the detected voltage signal and switch to the corresponding preset working mode, effectively improving the working efficiency of the underwater robot. In addition, this detection scheme uses the significant difference between the conductivity of water and the insulation of air as the detection principle, is not easily affected by environmental factors such as water turbidity and water flow disturbance, and has stronger environmental adaptability and detection reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a schematic diagram of the module connection of the water entry detection circuit in an embodiment of the underwater robot of the present invention;

[0046] Figure 2 It is a circuit diagram of the water entry detection circuit in an embodiment of the underwater robot of the present invention;

[0047] Figure 3 It is a schematic diagram of the structure in an embodiment of the underwater robot of the present invention;

[0048] Figure 4 It is a schematic flowchart of a method for detecting water entry in an embodiment of the present invention;

[0049] Figure 5 It is a schematic flowchart of another embodiment of the method for detecting water entry of the present invention;

[0050] Figure 6 It is a schematic flowchart of still another embodiment of the method for detecting water entry of the present invention;

[0051] Figure 7 It is a schematic flowchart of yet another embodiment of the method for detecting water entry of the present invention.

[0052] DESCRIPTION OF THE REFERENCE NUMERALS IN THE DRAWINGS:

[0053] 410, motor;

[0054] 411, propeller;

[0055] 412, electrode;

[0056] 100, conditioning circuit; A1, first control end; A2, first conducting end; A3, second conducting end; Q1, switching tube;

[0057] 110. Signal amplification module; B1. First input terminal; B2. First feedback terminal; U1. Operational amplifier;

[0058] 120. Low-pass filter; C1. First capacitor; C2. Second capacitor; R1. First resistor;

[0059] 130. Connection module;

[0060] 140. Main control chip;

[0061] 150. Protection circuit; D1. First transient diode; D2. Second transient diode;

[0062] 200. Housing;

[0063] 300. Environmental monitoring module.

[0064] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0065] Next, the solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0066] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0067] It should also be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time.

[0068] In addition, the descriptions involving "first", "second", etc. in the present invention are for descriptive purposes only, and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0069] Referring to Figure 1 and Figure 2 , an embodiment of the present invention provides an underwater robot, which includes a robot body. An underwater detection circuit and at least two motors 410 are provided on the robot body. An electrode 412 is provided on the output shaft of each motor 410. The underwater detection circuit is electrically connected to the electrode 412. The underwater detection circuit includes:

[0070] A conditioning circuit 100, the adjustment circuit includes a first control terminal A1, a first conduction terminal A2 and a second conduction terminal A3, and the first conduction terminal A2 is electrically connected to the power supply;

[0071] A signal amplification module 110, the signal amplification module 110 includes a first input terminal B1 and a first feedback terminal B2;

[0072] A connection module 130, the connection module 130 is electrically connected to the second conduction terminal A3 and the first input terminal B1 respectively;

[0073] A main control chip 140, the main control chip 140 is electrically connected to the first feedback terminal B2 and the first control terminal A1 respectively. The main control chip 140 is used to control the underwater robot to operate in a preset mode based on the voltage signal of the first feedback terminal B2.

[0074] In this embodiment, the conditioning circuit 100 can be implemented by a switching tube. Controlled by a PWM signal, the power supply is output with a preset duty cycle (which can be 50%) and frequency (which can be 1 kHz) to ensure the stability of the measurement signal.

[0075] The signal amplification module 110 can use an operational amplifier to achieve signal amplification. At the same time, a low-pass filter 120 can be configured, for example, the cut-off frequency is set to 100 Hz to effectively suppress electromagnetic interference in the working environment.

[0076] The connection module 130 can adopt a multi-layer PCB design, and the signal lines adopt a differential wiring method. At the same time, a protection circuit 150 can be further provided, such as a TVS tube and a voltage stabilizing diode, to prevent overvoltage and transient interference.

[0077] The main control chip 140 can select the STM32F103 series microcontroller, which has a 12-bit ADC with a sampling rate of up to 1MSPS and an internal 16K RAM, which is sufficient to support data processing requirements.

[0078] During the working process, when the robot is powered on but not in the water, the main control chip 140 obtains the initial resistance value (for example, greater than 1MΩ) through the first feedback terminal B2 and stores it as a reference value. At this time, the conditioning circuit 100 can output a 3.3V driving voltage, which is transmitted to the electrode 412 through the connection module 130. Due to the insulation of air, the resistance value between the electrodes 412 is relatively large, and the voltage output by the signal amplification module 110 is close to the full scale. The system enters the standby mode, and the main control chip 140 controls the motor 410 and other devices to remain stationary.

[0079] When the robot is placed in the water, water molecules begin to fill the gap between the electrodes 412, and at this time the resistance value drops sharply (for example, drops to the range of about 1 - 10kΩ). At this time, the voltage output by the second conduction terminal A3 passes through the electrode 412 and the output shaft of the motor 410, and then is amplified and processed in the signal amplification module 110. The main control chip 140 detects the voltage change, determines that the robot has entered the water, and then switches to the underwater working mode. For example, it starts the thruster and the sensor system, etc.

[0080] At the same time, the main control chip 140 can also monitor the sealing state inside the robot through the water leakage detection module. Specifically, the water leakage detection pin B3 can be connected to a water leakage sensor inside the housing. This sensor can be a bimetallic electrode type sensor - composed of two mutually insulated metal probes installed in the area prone to water leakage, or it can be a capacitive sensor, etc.;

[0081] In the normal working state, the water leakage detection pin B3 is kept at a high level through the resistor R18 (10kΩ). Once water leakage occurs inside, the moisture will form a low-resistance conduction path between the sensor contact points, pulling the voltage of the pin B3 below the threshold. This signal is conditioned by the operational amplifier U2 and then transmitted to the main control chip 140 to trigger the water leakage alarm process.

[0082] The entire system ensures the safe operation of the robot through a dual detection mechanism (water entry detection and water leakage detection). During the operation, the system continuously monitors the resistance value changes of the electrode 412 and the water leakage sensor, and can also adapt to different water quality environments through a dynamic threshold algorithm (for example, using a 100ms sliding window average) to ensure the accuracy and stability of the detection.

[0083] The beneficial effects of the technical solution of the present invention are as follows: By setting an electrode 412 on the output shaft of the motor 410 of the underwater robot and electrically connecting the electrode 412 to the water entry detection circuit, multi-point distributed detection is achieved, avoiding detection blind spots and improving the accuracy of detection; among them, the water entry detection circuit adopts a combined structure of a conditioning circuit 100, a signal amplification module 110 and a connection module 130, realizing the precise acquisition and effective processing of the resistance signal between the electrodes 412, and improving the stability and reliability of the detection signal; at the same time, through the electrical connection design of the main control chip 140 with the first feedback end B2 and the first control end A1, the system can quickly respond according to the detected voltage signal and switch to the corresponding preset working mode, effectively improving the working efficiency of the underwater robot; in addition, this detection scheme uses the significant difference between the conductivity of water and the insulation of air as the detection principle, is not easily affected by environmental factors such as water turbidity and water flow disturbance, and has stronger environmental adaptability and detection reliability.

[0084] Continue to refer to Figure 2 , in this embodiment, the underwater robot further includes a protection circuit 150, and the protection circuit 150 includes:

[0085] A first transient diode D1, one end of the first transient diode D1 is electrically connected to the second conduction end A3, and the other end of the transient diode is grounded;

[0086] A second transient diode D2, one end of the second transient diode D2 is electrically connected to the connection module 130 and the first input end B1, and the other end of the second transient diode D2 is grounded.

[0087] In this embodiment, the protection circuit 150 of the underwater robot adopts a dual transient diode structure to achieve overvoltage and surge protection. Among them, one end of the first transient diode D1 is electrically connected to the second conduction end A3 of the conditioning circuit 100, and the other end is grounded, which is used to protect the output end of the conditioning circuit 100 from the damage of reverse current or overvoltage of the external circuit. When a voltage higher than the breakdown voltage of the transient diode appears at the second conduction end A3, the transient diode conducts and conducts the overvoltage current into the ground wire, thereby ensuring the safe operation of the conditioning circuit 100.

[0088] One end of the second transient diode D2 is simultaneously electrically connected to the connection module 130 and the first input end B1 of the signal amplification module 110, and the other end is grounded, mainly used to protect the signal acquisition circuit. Since there may be static electricity accumulation or electromagnetic interference in the underwater environment, it is easy to generate transient high voltage in the measurement circuit. The second transient diode D2 limits the signal exceeding the protection voltage within a safe range through a fast clamping action, preventing the signal amplification module 110 from being damaged. This dual protection structure not only improves the reliability of the circuit, but also enhances the anti-interference ability of the system in the complex underwater environment.

[0089] Continue to refer to Figure 2 In this embodiment, the conditioning circuit 100 includes:

[0090] A switching transistor Q1, one conduction end of the switching transistor Q1 is electrically connected to a power supply, the other conduction end is electrically connected to the connection module 130 through a first resistor R1, and the trigger end of the switching transistor Q1 is electrically connected to a first control terminal.

[0091] In this embodiment, the core component of the conditioning circuit 100 is the switching transistor Q1. One conduction end thereof is connected to the power supply VCC, the other conduction end is electrically connected to the connection module 130 through the first resistor R1, and the trigger end of the switching transistor Q1 is connected to the first control end A1 of the main control chip 140. The switching transistor Q1 can be implemented by using devices such as a PNP triode, an NPN triode or a MOS transistor. In this embodiment, a PNP triode is preferably used, which has the advantages of good switching characteristics and low drive current requirements.

[0092] In actual work, the base of the PNP triode receives a control signal from the main control chip 140. The main control chip 140 controls the conduction and cut-off of the triode by outputting a PWM waveform, thereby realizing the periodic switching of the power supply voltage. By adjusting the frequency (for example, 1 kHz) and duty cycle (for example, 50%) of the PWM signal, a stable measurement excitation signal can be generated. This solution can effectively reduce the influence of the polarization effect of the electrode 412 and improve the measurement accuracy compared with the continuous power supply method.

[0093] Furthermore, the setting of the two second resistors plays a role in current limiting protection to prevent the switching transistor Q1 from generating too large a current when conducting. At the same time, this resistor and the subsequent circuit form a voltage dividing network, which can adjust the power supply voltage to a suitable measurement range. In addition, this switching power supply scheme also has the characteristics of low power consumption and small heat generation, and is suitable for application scenarios such as underwater robots that have strict requirements for power consumption and thermal management.

[0094] Continue to refer to Figure 2 In this embodiment, the signal processing module includes:

[0095] An operational amplifier U1, the non-inverting input terminal of the operational amplifier U1 is electrically connected to the first input terminal B1, and the output terminal is electrically connected to the first feedback terminal B2;

[0096] A low-pass filter 120, the low-pass filter 120 is electrically connected between the first input terminal B1 and the inverting terminal of the operational amplifier U1, and is used for filtering the output voltage signal.

[0097] In this embodiment, the signal processing module can adopt a combined design of an operational amplifier U1 and a low-pass filter 120 to achieve precise signal amplification and interference suppression. Among them, the operational amplifier U1 is configured as a voltage follower, with its non-inverting terminal electrically connected to the first input terminal B1, the output terminal electrically connected to the first feedback terminal B2, and the inverting terminal for signal conditioning through the low-pass filter 120.

[0098] The setting of the operational amplifier U1 mainly solves two key problems: First, due to the large variation range of the resistance value between the electrodes 412 in the underwater environment, the high-gain characteristic of the operational amplifier U1 can convert weak resistance changes into voltage signals that are easily recognizable by the main control chip 140; Second, the high input impedance characteristic of the operational amplifier U1 effectively reduces the influence of the measurement circuit on the measured resistance and improves the measurement accuracy. In this embodiment, a high-precision operational amplifier U1 chip (such as OP07 or AD8628) can be used, which has low offset voltage (typical value less than 50 μV) and low temperature drift characteristics, ensuring the stability of the measurement results when the underwater environmental temperature changes.

[0099] The low-pass filter 120 is arranged between the first input terminal B1 and the inverting terminal of the operational amplifier U1, adopting an RC filter circuit structure composed of a resistor and a capacitor. By reasonably selecting the RC parameters, the cut-off frequency can be set within the required range (for example, 100 Hz), effectively filtering out high-frequency interference signals. In this way, not only can the electromagnetic interference generated by the operation of the underwater motor 410 be suppressed, but also the influence of environmental noise on the measurement results can be reduced, making the voltage signal received by the main control chip 140 more stable and reliable.

[0100] Specifically, continue to refer to Figure 2 In this embodiment, the low-pass filter 120 includes:

[0101] A first capacitor C1, one end of the first capacitor C1 is electrically connected to the first input terminal B1, and the other end of the first capacitor C1 is grounded;

[0102] A second capacitor C2, the second capacitor C2 is connected to the first input terminal B1, and the other end of the second capacitor C2 is electrically connected to the inverting terminal of the operational amplifier U1;

[0103] A first resistor R1, one end of the first resistor R1 is electrically connected to the inverting terminal of the operational amplifier U1, and the other end of the first resistor R1 is grounded.

[0104] Refer to Figure 3 In the embodiment, the underwater robot further includes:

[0105] A housing 200;

[0106] The motor 410, two motors 410 are arranged side by side and spaced inside the housing 200, the output shafts of the two motors 410 penetrate the housing 200, and a propeller 411 is provided;

[0107] The environmental monitoring module 300, the environmental monitoring module 300 is arranged in the housing 200 for detecting the surrounding environment;

[0108] Among them, the motor 410 and the environmental detection module are electrically connected to the main control chip 140, and the main control chip 140 controls the operation of the motor 410 and the environmental monitoring module 300 according to the voltage of the first feedback terminal B2.

[0109] In this embodiment, the housing 200 can be made of materials with excellent corrosion resistance, high strength, and waterproof performance, such as stainless steel, titanium alloy, or special engineering plastics. The shape of the housing 200 can be designed according to actual needs, for example, streamlined to reduce water resistance, or spherical to improve compressive capacity. Two motors 410 are arranged side by side and spaced inside the housing 200, and the output shafts of the motors 410 penetrate the housing 200 and are connected to the propeller 411 for driving the underwater robot to move.

[0110] The environmental monitoring module 300 is arranged on the housing 200 and integrates a variety of sensors, such as water quality sensors, depth sensors, temperature sensors, etc., for real-time monitoring of underwater environmental parameters. In addition, the environmental monitoring module 300 can also include infrared and sonar detection units for monitoring underwater organisms.

[0111] During the working process, both the motor 410 and the environmental monitoring module 300 are electrically connected to the main control chip 140. The main control chip 140 receives the voltage signal of the first feedback terminal B2, controls the rotation speed and direction of the motor 410 according to the preset program, and adjusts the motion state of the underwater robot; at the same time, the main control chip 140 can also dynamically adjust the detection strategy according to the data collected by the environmental monitoring module 300, such as increasing the sampling frequency when the water quality is abnormal, or starting the tracking mode when a target organism is found. The environmental monitoring data can be uploaded to the control center on the water surface in real time through the wireless communication module for remote monitoring.

[0112] The underwater robot of this embodiment can achieve comprehensive perception of the underwater environment by integrating the environmental monitoring module 300, and by adding infrared and sonar units, it greatly expands the means of biological monitoring. At the same time, the main control chip 140 intelligently adjusts the strategy according to the feedback voltage and monitoring data, enabling the robot to flexibly respond to the changing underwater environment.

[0113] Refer to Figure 4, the present invention further provides a water entry detection method, which is applied to the underwater robot in the above embodiment. This method can effectively monitor the water entry state and operating state of the underwater robot, and adopt corresponding control strategies according to the state changes, improving the adaptability and safety of the underwater robot. The water entry detection method includes the following steps:

[0114] Step S10, obtain the reference resistance value between the shafts of the motor 410 of the underwater robot. When the underwater robot leaves the factory or is maintained, measure the resistance value between the shafts of the motor 410 in a dry environment, and store it as a reference value in the memory of the main control chip 140 for subsequent comparison and judgment.

[0115] Step S20, detect the current resistance value between the shafts of the motor 410 of the underwater robot. When the underwater robot is working, the main control chip 140 continuously detects the resistance value between the shafts of the motor 410 as the current resistance value. Since water has conductivity, when the robot enters the water, the resistance value between the shafts of the motor 410 will decrease significantly.

[0116] Step S30, based on the comparison result between the current resistance value and the reference resistance value, judge the water entry state of the underwater robot. The main control chip 140 compares the current resistance value with the reference value. If the current value is significantly lower than the reference value (such as less than 20% of the reference value), it is judged that the robot has entered the water; otherwise, it is judged that the robot has not entered the water.

[0117] Step S40, in response to the water entry state, control the working mode of the underwater robot. Once it is judged that the robot has entered the water, the main control chip 140 immediately executes the working mode after entering the water, such as turning on the thruster, the environmental monitoring module 300, etc., to make the robot work normally underwater.

[0118] Step S50, monitor the operating state of the underwater robot. During the underwater operation of the robot, the main control chip 140 continuously monitors the operating state of the robot through various sensors, such as key parameters including depth, attitude, speed, power, etc., as well as external information such as water quality and terrain feedback by the environmental monitoring module 300.

[0119] Step S60, in response to the operating state, trigger a preset control strategy. The main control chip 140 flexibly triggers various preset control strategies according to the changes in the operating state, such as: when the depth exceeds the safety threshold, control the robot to float; when the speed is too fast, reduce the power of the thruster; when the power is insufficient, guide the robot to return for charging; when encountering complex terrain, switch to the obstacle avoidance mode, etc. Through these strategies, the autonomy and safety of the robot are enhanced.

[0120] The water entry detection method proposed in this embodiment can accurately judge the water entry state of the underwater robot by using the significant change in the inter-axis resistance value of the motor 410, and automatically activate the underwater working mode, eliminating manual operation. At the same time, by real-time monitoring the running state of the robot and dynamically triggering various control strategies, the robot can flexibly respond to changes in the underwater environment, improving the operation efficiency and success rate.

[0121] During the implementation of the water entry detection method, the complexity of the underwater environment may cause small fluctuations in the inter-axis resistance value of the motor 410, affecting the accuracy of judging the water entry state. For example, factors such as water flow fluctuations and water quality changes may cause changes in the resistance value. To address this issue, this embodiment proposes an improved scheme for dynamically adjusting the reference resistance value range.

[0122] Refer to Figure 5 , in this embodiment, the step of detecting the current inter-axis resistance value of the motor 410 of the underwater robot further includes:

[0123] Step S100, collect multiple current resistance values within a preset time window. The main control chip 140 continuously collects the resistance values between the shafts of the motor 410 at a certain sampling frequency (such as 10 times per second), and stores the sampling values within a recent period of time (such as 5 seconds) as a set of data to form a sliding time window.

[0124] Step S200, calculate the mean and standard deviation of multiple current resistance values. Conduct statistical analysis on a set of resistance value data within the time window, calculate its arithmetic mean as the representative value of the resistance value within this time period; at the same time, calculate the standard deviation of this set of data to reflect the fluctuation degree of the resistance value.

[0125] Step S300, dynamically adjust the range of the reference resistance value based on the mean and standard deviation. Dynamically set the upper and lower limits of the reference resistance value according to the calculated mean and standard deviation. Specifically, for example, set the upper limit of the reference value to "mean + 3 times the standard deviation" and the lower limit to "mean - 3 times the standard deviation" to form a dynamic reference interval. This interval covers most of the normally fluctuating resistance values, and values that significantly exceed the interval are likely to be caused by water entry.

[0126] When judging the water entry state, compare the current resistance value with the dynamically adjusted reference interval. If the current value is lower than the lower limit of the reference interval, it is judged that the robot has entered the water; if it is higher than the upper limit of the reference interval, it is judged as an abnormal situation and may require further inspection; if it is within the reference interval, it is judged that the robot has not entered the water.

[0127] In this embodiment, the method of sliding time window and statistical analysis can also be adopted to process the collected resistance value data in real time, filter out the fluctuations within the normal range, and more accurately judge the water entry state. The overall level of the resistance value is reflected by the mean value, the fluctuation range of the resistance value is quantified by the standard deviation, and the judgment interval of the reference value is dynamically adjusted to adapt to the changes in the underwater environment.

[0128] To further improve the accuracy and reliability of the resistance value measurement, after collecting multiple current resistance values, the system will also perform smoothing processing on these data to eliminate the influence of various noise interferences. Specifically, referring to Figure 6 In this embodiment, the step of collecting multiple current resistance values within a preset time window further includes:

[0129] Step S101, smoothing multiple current resistance values to eliminate noise interference. In this embodiment, a sliding average filtering algorithm can be used to process the collected resistance values. Specifically, within a preset time window (for example, 200 ms), a weighted average calculation is performed on N consecutive sampling points (for example, N = 20).

[0130] This kind of smoothing processing mainly aims at three types of interferences in the underwater environment: First, the high-frequency electromagnetic interference generated by the operation of the motor 410; second, the measurement fluctuation caused by the water flow fluctuation; and finally, the mutation interference caused by the adsorption of bubbles or impurities on the surface of the electrode 412. Through the sliding average filtering, the system can effectively suppress these interferences and obtain more stable resistance value data. Among them, the newer sampling points are given larger weights, and the older sampling points are given smaller weights. This kind of weighting method not only ensures the real-time nature of the data but also maintains a good filtering effect.

[0131] In addition, this embodiment can also add an outlier rejection mechanism. For example, when the resistance value of a certain sampling point deviates from the previous and subsequent sampling points by more than a preset threshold (for example, ±20% of the mean value), the system will automatically determine this point as an outlier and eliminate it during the smoothing processing. This way can prevent the sudden strong interference signal from affecting the overall measurement accuracy and make the water entry detection function of the underwater robot more stable and reliable.

[0132] Referring to Figure 7 In this embodiment, the step of monitoring the operating state includes:

[0133] Step S500, continuously detecting the resistance value between the shafts of the motor 410;

[0134] Step S600, judging whether there is an abnormal contact of the electrode 412 of the underwater robot based on the change trend of the resistance value between the shafts of the motor 410.

[0135] Among them, the preset control strategies include at least one of the following:

[0136] Send out an alarm signal;

[0137] Stop the operation of the underwater robot;

[0138] Control the underwater robot to float to the water surface.

[0139] In this embodiment, during the normal operation of the underwater robot, it continuously monitors the resistance value between the shafts of the motor 410 and judges the working state of the robot based on the change trend of the resistance value. Specifically, the system samples the resistance value between the shafts of the motor 410 in real time (for example, the sampling frequency is 10 Hz), and conducts trend analysis on the sampled data. When an abnormal change in the resistance value is detected, the system will automatically judge the possible fault types. The specific fault types are, for example, poor electrode contact, etc.

[0140] When the contact of the electrode 412 is abnormal, the resistance value between the shafts of the motor 410 will present a characteristic change pattern. In the normal state, the resistance value remains within the set range and the fluctuation amplitude is small; when there is a slight abnormality, the resistance value may fluctuate for a short time but can recover by itself; while in the severe abnormal state, it is manifested as a mutation trend of the resistance value.

[0141] Once an abnormal electrode contact is detected, the signal will trigger the corresponding control strategy after being evaluated by the main control chip 140 yuan. For example, for a slight abnormality, the system will send out an alarm signal but maintain normal operation; in the case of moderate abnormality, the system will send out an alarm and reduce the operating power to slow down the possible damage; while in the case of severe abnormality, the system will immediately execute the safe floating program and return to the water surface through the preset route.

[0142] This complete detection mechanism ensures that the underwater robot can identify potential risks at the early stage when the contact of the electrode 412 is abnormal, effectively preventing motor damage and system failures caused by seawater infiltration, thereby greatly improving the reliability and mission persistence of the underwater robot.

[0143] The above are only partial or preferred embodiments of the present invention. Neither the text nor the drawings can limit the scope of protection of the present invention. All equivalent structural transformations made under the overall concept of the present invention by using the content of the specification and drawings of the present invention, or directly / indirectly applied in other related technical fields are included in the scope of protection of the present invention.

Claims

1. An underwater robot, characterized in that: The robot body comprises a water entry detection circuit and at least two motors, each of the motors has an electrode disposed on its output shaft, the water entry detection circuit is electrically connected to the electrodes, and the water entry detection circuit comprises: A conditioning circuit, the conditioning circuit comprising a first control terminal, a first conduction terminal and a second conduction terminal, the first conduction terminal being electrically connected to a power supply; A signal amplification module, the signal amplification module comprising a first input terminal and a first feedback terminal; a connecting module, the connecting module being electrically connected to the second conducting end and the first input end respectively; A main control chip, wherein the main control chip is electrically connected to the first feedback end and the first control end respectively, and the main control chip is used to control the underwater robot to operate in a preset mode based on a voltage signal at the first feedback end.

2. The underwater robot according to claim 1, characterized in that: Also included is a protection circuit, the protection circuit comprising: A first transient diode, one end of the first transient diode is electrically connected to the second conduction end, and the other end of the first transient diode is grounded; A second transient diode, one end of which is electrically connected to the connection module and the first input end, and the other end of which is grounded.

3. The underwater robot according to claim 1, characterized in that: The conditioning circuit comprises: A switch tube, one conducting end of the switch tube is electrically connected to a power supply, the other conducting end is electrically connected to the connection module via a first resistor, and the triggering end of the switch tube is electrically connected to the first control terminal.

4. The underwater robot according to claim 1, characterized in that: The signal processing module comprises: an operational amplifier, wherein a non-phase terminal of the operational amplifier is electrically connected to the first input terminal, and an output terminal of the operational amplifier is electrically connected to a first feedback terminal; A low-pass filter is electrically connected between the first input terminal and the inverting terminal of the operational amplifier, and is used for filtering the input voltage signal.

5. The underwater robot according to claim 4, characterized in that: The low pass filter comprises: A first capacitor, one end of the first capacitor is electrically connected to the first input end, and the other end of the first capacitor is grounded; a second capacitor, wherein one end of the second capacitor is connected to the first input terminal, and the other end of the second capacitor is electrically connected to the inverting terminal of the operational amplifier; A first resistor, one end of the first resistor is electrically connected to the inverting end of the operational amplifier, and the other end of the first resistor is grounded.

6. The underwater robot according to claim 1, characterized in that: The underwater robot also includes: case; Motors, two of the motors are arranged side by side and at intervals in the housing, the output shafts of the two motors pass through the housing and are provided with propellers; An environment monitoring module, which is disposed in the housing and is used to detect the surrounding environment; The motor and the environment detection module are electrically connected to the main control chip, and the main control chip controls the motor and the environment monitoring module to work according to the voltage of the first feedback end.

7. A water entry detection method, applied to an underwater robot, characterized in that: The water entry detection method comprises: Obtaining a reference resistance value between motor shafts of the underwater robot; Detecting the current resistance value between the motor shafts of the underwater robot; Based on the comparison result between the current resistance value and the reference resistance value, determining the water entry state of the underwater robot; In response to the water entry state, controlling the working mode of the underwater robot; Monitoring the operating status of the underwater robot; In response to the operating state, a preset control strategy is triggered.

8. The water entry detection method according to claim 7, characterized in that: The step of detecting the current resistance value between the motor shafts of the underwater robot also includes: Collecting a plurality of current resistance values ​​within a preset time window; Calculating a mean and a standard deviation of the plurality of current resistance values; The range of the reference resistance value is dynamically adjusted based on the mean value and the standard deviation.

9. The water entry detection method according to claim 8, characterized in that: The step of collecting a plurality of current resistance values ​​within a preset time window further comprises: The plurality of current resistance values ​​are smoothed to eliminate noise interference.

10. The water entry detection method according to claim 7, characterized in that: The step of monitoring the operating status comprises: Continuously detecting the motor shaft resistance value; Based on the variation trend of the motor shaft resistance value, it is determined whether the underwater robot has abnormal electrode contact.

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