An adaptive adsorption control method of a steel bridge rust removal robot

Abstract

The present application belongs to the technical field of steel bridge detection and maintenance, and particularly relates to a self-adaptive adsorption control method of a steel bridge rust removal robot. According to the actual scene of the rust removal robot during rust removal operation on the wall surface of the steel bridge, the electromagnetic wheels are divided into the rusted area and the non-rusted area for self-adaptive adsorption control, so that the adsorption state of each electromagnetic wheel can be more accurately adjusted. The PID control algorithm is used for self-adaptive adjustment of the electromagnetic adsorption force of the rust removal robot, the electromagnetic adsorption force of the electromagnetic wheel is automatically adjusted according to the obtained electromagnetic wheel current regulation value, and the self-adaptive adsorption of the rust removal robot on the different wall surfaces of the steel bridge is realized.

Description

Technical field:

[0001] The invention relates to the technical field of steel bridge wall-climbing robots, and in particular to an adaptive adsorption control method of a steel bridge rust removal robot. Background technology:

[0002] Due to long-term exposure to complex environments, steel bridges are prone to corrosion, which in turn affects their durability and even endangers their safety. Inspection and rust removal are an effective means of steel bridge maintenance. Rust removal robots are an effective alternative to manual labor, but existing robots in shipbuilding and other related fields have a low level of automation, and their suction force cannot adapt to the varying corrosion conditions and wall angles of steel bridges, as well as to both mobile and stationary operation.

[0003] Patent document CN116394270A discloses a bridge rust removal and painting robot and its use method. The above patent realizes the robot's movement, crawling, fixing and rust removal and painting operations on the steel bridge. It is installed on the H-shaped steel of the bridge. The main sliding mechanism and side sliding mechanism are designed in conjunction with the H-shaped steel structure to clamp the steel and move. The application occasions of this rust removal robot are limited. It is not suitable for steel of other structural forms, and it cannot realize the robot's function of adjusting the size of electromagnetic adsorption force on different wall surfaces of the steel bridge.

[0004] Patent document CN108655077A discloses a wall-climbing rust removal robot and its double adsorption method. The above patent realizes double adsorption by combining electromagnets and permanent magnets to ensure that the robot can operate normally under any circumstances. When the power is off, the permanent magnet can still maintain the adsorption state to prevent the robot from falling from the adsorption surface. According to different work requirements, the adsorption force generated by the electromagnet is adjusted only according to the current size in the first electromagnet (located in the center of the robot) and the second electromagnetic coil (used to control the permanent magnet). The entire area where the vehicle body is located cannot be adjusted in different areas, and the robot cannot realize the electromagnetic adsorption force adjustment function of the electromagnetic wheels located in different rust areas according to the actual rust condition of the steel bridge surface.

[0005] In summary, the existing technology cannot realize the robot's adaptive adsorption and movement function under different corrosion conditions and different wall surfaces of steel bridges. Therefore, this application proposes a control method that can realize the adaptive adsorption and movement function under different corrosion conditions and different wall surfaces of steel bridges. Summary of the invention:

[0006] The purpose of the present invention is to provide an adaptive adsorption control method for a steel bridge rust removal robot, which aims to solve the problems of low automation and inability to adapt the adsorption force during the movement and operation of the steel bridge wall-climbing rust removal robot on different walls of the steel bridge during bridge inspection and maintenance. The present invention can divide the electromagnetic wheel into two parts, located in the rusted area and the non-rusted area, for adaptive adsorption control according to the actual scenario when the rust removal robot performs rust removal operations on the wall of the steel bridge, so as to achieve the robot's ability to adjust the electromagnetic adsorption force on the walls of the steel bridge with different rust and different inclination angles and during the transition of the wall, thereby achieving safe movement and stable adsorption, thereby improving the adaptive adsorption function of the rust removal robot on the wall of the steel bridge.

[0007] To achieve the above object, the technical solution of the present invention is:

[0008] In a first aspect, the present invention provides an adaptive adsorption control method for a steel bridge rust removal robot, wherein the rust removal robot uses four electromagnetic wheels for walking, wherein the front two electromagnetic wheels are located in a rusted area and provide the same electromagnetic driving force, and the rear two electromagnetic wheels are located in a non-rusted area and provide the same electromagnetic driving force. A cleaning disc is provided in the middle of the robot, and the cleaning disc is used to contact the steel bridge wall to remove rust from the steel bridge wall. Pressure sensors for measuring support reaction force are installed on the four electromagnetic wheels and the cleaning disc; the rust removal robot is also equipped with an inclination sensor for measuring the inclination angle of the steel bridge working surface and the angle of the transition wall, and a laser rangefinder for detecting whether it is a transition wall. The adaptive control method comprises the following steps:

[0009] When the rust removal robot performs rust removal on the steel bridge wall, one part of the electromagnetic wheel moves on the rusted area, while the other part of the electromagnetic wheel moves on the wall after rust removal. The steel bridge wall is divided into an inclined wall working condition and a transition zone working condition caused by the intersection of two inclined walls. In the transition zone working condition, there is an angle between the two inclined walls.

[0010] For the inclined wall working condition, when the rust removal robot moves and removes rust on the wall of the steel bridge with different inclination angles, the force balance equation in the direction perpendicular to the inclined wall of the steel bridge is considered, which ensures that the rust removal robot can safely adsorb on the wall and walk without sliding, as well as the moment balance equation that ensures that the robot can safely work on the steel bridge wall without overturning. The electromagnetic adsorption force value range of the electromagnetic wheel in the rusted area and the non-rusted area is obtained; the minimum value of the electromagnetic adsorption force of the electromagnetic wheel in the rusted area is taken as the theoretical value F of the electromagnetic adsorption force of the electromagnetic wheel in the rusted area. cs1 The minimum value of the electromagnetic adsorption force of the electromagnetic wheel in the non-corrosion area is taken as the theoretical value of the electromagnetic adsorption force of the electromagnetic wheel in the non-corrosion area F cs2 ;

[0011] For the transition zone working conditions, the rust-removing robot moves and removes rust on the wall surface in the transition state of the steel bridge wall. The force balance in the parallel direction of the inclined wall surface before transition and the force balance perpendicular to the inclined wall surface before transition, as well as the force balance in the parallel direction of the inclined wall surface after transition and the force balance perpendicular to the target wall surface after transition, are respectively considered to obtain the theoretical value F of the electromagnetic adsorption force of the electromagnetic wheel in the rusted area of the wall surface transition ct1 and the theoretical value F of the electromagnetic adsorption force of the electromagnetic adsorption force in the non-rusted area of the wall surface transition ct2 ;

[0012] Calculate the theoretical value of the current for each of the electromagnetic adsorption forces of the electromagnetic wheels in the rusted area and the non-rusted area under different working conditions, and use the theoretical value of the current as the current target value of the PID control algorithm;

[0013] Calculate the error value between the actual value of the current and the current target value of the electromagnetic wheel in different areas under different working conditions, input the error value into the PID control algorithm, and use the PID control algorithm to adjust the actual value of the current of the corresponding electromagnetic wheel in real time, so as to realize the real-time control of the magnitude of the electromagnetic adsorption force of the electromagnetic wheel. »

[0014] Furthermore, the theoretical value of the electromagnetic adsorption force of the electromagnetic wheel located in the rusted area is corrected according to the following formula,

[0015]

[0016] where F1 and F2 are respectively the theoretical values of the electromagnetic adsorption forces of the electromagnetic wheels in the rusted area after correction under the inclined wall surface working conditions and the transition zone working conditions; γ is a characteristic parameter related to the rust thickness and rust magnetic permeability of the steel bridge surface, and is obtained according to the following formula:

[0017]

[0018] where is the ratio of the relative magnetic permeability of the original steel plate to the composite relative magnetic permeability of the steel plate and rust, and β is the ratio of the change in the electromagnetic adsorption force caused by the increase in the electromagnetic adsorption force gap δ caused by the rust thickness; c is the gap coefficient caused by rust, 0 < c < 1; b is the ratio of the rust thickness to the steel plate thickness, 0 < b < 1%; μ r1 is the relative magnetic permeability of the steel bridge; μ r2 is the relative magnetic permeability after rust; t2 is the rust thickness;

[0019] Calculate the theoretical value of the current for each of F1 and F2, and then use the PID control algorithm to perform real-time regulation of the electromagnetic adsorption force.

[0020] Furthermore, the incremental Simpson-PID control algorithm is used to control the current adjustment amount of the current target values of the rusted area and the non-rusted area,

[0021] The incremental Simpson-PID control algorithm is used to control the current of the two electromagnetic wheels in the non-corrosion area:

[0022]

[0023] in

[0024]

[0025] ΔI k K is the current adjustment value of the electromagnetic wheel located in the non-rusting area output by the control system of the rust removal robot. a1 is the reference value of the proportional coefficient, K b1 is the reference value of the integral coefficient, K c1 is the differential coefficient reference value, e k+1 is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the k+1th moment, e k is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the kth moment, e k-1 is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the k-1th moment, I t is the target value of electromagnetic wheel current in non-corrosion area, I m is the actual value of the electromagnetic wheel current in the non-corroded area, k+1 represents the sampling at the k+1th moment, k represents the kth moment, k-1 represents the k-1th moment, n is the number of moments of the final sampling of the system, i and j are ordinal numbers, τ is the filter time constant, and s is the complex frequency variable in the Laplace transform;

[0026] The incremental Simpson-PID control algorithm controls the current of the two electromagnetic wheels in the rusted area as follows:

[0027]

[0028] in

[0029]

[0030] ΔI k ' is the current adjustment of the electromagnetic wheel located in the rusted area calculated by the control system of the rust removal robot, K a (ε) is the proportional control coefficient of the electromagnetic wheel current in the rusted area, K b (ε) is the integral control coefficient of the electromagnetic wheel current regulation in the rusted area, K c (ε) is the differential control coefficient of the electromagnetic wheel current regulation in the rusted area, e k+1 ' is the real-time error value of the electromagnetic wheel in the rusted area sampled at the k+1th moment, e k ' is the real-time error value of the electromagnetic wheel in the rusted area sampled at the kth moment, e k-1' is the real-time error value of the electromagnetic wheel in the rusted area sampled at the k-1th moment, I t ' is the target current value of the electromagnetic wheel located in the rusted area, I m ' is the actual value of the electromagnetic wheel current in the rusted area, τ is the filter time constant, s is the complex frequency variable in Laplace transform; ε is the relative error,

[0031] Furthermore, K a (ε), K b (ε), K c The expression of (ε) is:

[0032]

[0033] Among them, g(ε) is a nonlinear function of the relative error value ε, and the expression is:

[0034]

[0035] Where q is a constant between 0 and 1, and sign is a sign function.

[0036] In a second aspect, the present invention provides a steel bridge rust removal robot, which adopts the adaptive adsorption control method to perform mobile rust removal control.

[0037] Furthermore, the rust removal robot includes a control system, a high-pressure pump, a cleaning tray, a storage chamber, a laser rangefinder 8, an electromagnetic wheel 9, a motor driver 10, a pressure sensor 11, an inclination sensor 12, a motor 13, a low-pass filter 14 and a robot body, wherein the storage chamber is used to store the rust removal reagent; the high-pressure pump is used to pump the rust removal reagent in the storage chamber to the cleaning tray;

[0038] Four electromagnetic wheels 7 are connected to the robot body and are placed at the left front, right front, left rear and right rear positions of the robot body; a groove is set every 45° on the rolling surface of each electromagnetic wheel, and a pressure sensor is installed in each groove to collect the support reaction force between the electromagnetic wheel and the steel bridge. A groove is opened under the cone of the cleaning disk and a pressure sensor is embedded in it to collect the support reaction force between the cleaning disk and the steel bridge; the motor 13 is placed under the robot body and is connected to the electromagnetic wheel 9 through a rotating shaft to drive the electromagnetic wheel to move on the wall of the steel bridge. Each electromagnetic wheel is controlled by a separate motor; the motor driver 10 is placed on the support plate above the robot body and is connected to the electromagnetic wheel 7 and the motor 13. It is used to receive the control signal of the control system to output current to the electromagnetic wheel and feed back the real-time current value of the electromagnet to the control system and control the start of the motor;

[0039] Two laser rangefinders 8 are provided, one laser rangefinder 8 is provided at the front of the robot body, for monitoring obstacles ahead, and the other laser rangefinder is provided on the lower truss at the front of the robot body, facing the steel bridge wall, for monitoring whether the robot body moves to the transition area and detecting whether there is a risk of stepping into the air;

[0040] The inclination sensor 12 is placed on the truss below the robot body and is used to measure the inclination angle of the working surface of the steel bridge.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] The present invention provides an adaptive adsorption control method for a steel bridge rust removal robot. According to the working scenario of the rust removal robot during rust removal operations on the wall of a steel bridge, the electromagnetic wheels located in the rusted area and the non-rusted area are automatically regulated using an adaptive control algorithm according to the characteristics of the working area, thereby achieving precise control of the adsorption status of the wheels in different areas.

[0043] In this invention, the theoretical value of the electromagnetic adsorption force is derived by considering two operating conditions: rust removal on moving walls with different inclination angles, and wall transitions. Corresponding mechanical equilibrium equations are constructed accordingly, expanding the range of applicable operating conditions for the theoretical calculation. To calculate the current adjustment value for the electromagnetic wheel in the non-corroded zone, an incremental Simpson-PID control algorithm is employed, incorporating both the current and real-time error values ​​of the electromagnetic wheel and the error values ​​of the previous two moments. This improves calculation accuracy, and a low-pass filter is introduced to reduce the impact of noise on the differential operation of the PID controller. In the calculation of the current adjustment value of the electromagnetic wheel located in the rust area, a characteristic parameter of rust thickness and rust magnetic permeability is first used to adjust the theoretical value of the electromagnetic adsorption force to increase its electromagnetic adsorption force, which helps to ensure the stability of the rust removal robot's adsorption on the steel bridge. Then, a nonlinear function based on the relative error of the electromagnetic wheel current is constructed, and the proportional coefficient, integral coefficient and differential coefficient are dynamically corrected accordingly. The constructed nonlinear function can make the corrected coefficient more stable as the error changes, reducing the oscillation or divergence caused by excessively large or small error step size. Then, an incremental Simpson-PID control algorithm that is more in line with actual working conditions is given for adaptive adsorption control, which improves the adsorption stability of the electromagnetic wheel located in the rust area during mobile rust removal.

[0044] The present invention solves the problem that the rust removal robot becomes unstable or even detaches from the steel bridge wall due to different corrosion conditions on different walls of the steel bridge, resulting in the electromagnetic adsorption force of the electromagnetic wheel located in the rusted area and the non-rusted area being difficult to control separately and the control method being unreasonable. Description of the drawings:

[0045] Figure 1 This is a schematic diagram of the overall structure of a rust removal robot according to an embodiment of the present invention from a top view;

[0046] Figure 2 This is a schematic diagram of the overall structure of an embodiment of the rust removal robot according to the present invention from a bottom-up perspective;

[0047] Figure 3 This is a mechanical analysis diagram of the rust removal robot on the inclined wall of a steel bridge;

[0048] Figure 4 Mechanical analysis diagram of the rust removal robot transitioning on the wall of a steel bridge;

[0049] Figure 5 Schematic diagram of adaptive adsorption control and adjustment of the electromagnetic adsorption force of the electromagnetic wheel located in the non-corrosion area of ​​the present invention;

[0050] Figure 6 Schematic diagram of adaptive adsorption control and adjustment of the electromagnetic adsorption force of the electromagnetic wheel located in the rusted area in the present invention;

[0051] Figure 7 This is the image of the nonlinear function g(ε) proposed in the present invention when q=0.5;

[0052] Figure 8 The adjusted proportional coefficient is set at q = 0.5, k a1 =4 when the image;

[0053] Figure 9 The adjusted integral coefficient is q=0.5, k b1 =0.4;

[0054] Figure 10 The adjusted differential coefficient is adjusted at q = 0.5, k c1 =1. Specific implementation method:

[0055] The present invention will be described in detail below with reference to the accompanying drawings, clearly and completely describing the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0056] Example 1

[0057] In this embodiment, the steel bridge rust removal robot includes a control system, a rust removal device, an intelligent recognition device, an adaptive adsorption device, and a robot body. The intelligent recognition device can be used to assist in obstacle avoidance, etc.

[0058] The control system includes a central processing unit 1, a power supply 2, and a display 3. The central processing unit 1 is connected to the display 3, and the power supply 2 supplies power to its electrical equipment through a relay. The rust removal device includes a high-pressure pump 4, a booster chamber 5, a storage chamber 6, and a cleaning disk 7. The booster chamber is connected to the storage chamber and the high-pressure pump 4 and the cleaning disk 7 respectively. The rust removal agent stored in the storage chamber (the rust removal agent can be water or an aqueous solution containing a rust removal agent) is pressurized in the booster chamber and then sprayed out by the cleaning disk 7 for rust removal. The adaptive adsorption device includes a laser rangefinder 8, an electromagnetic wheel 9, a motor driver 10, a pressure sensor 11, an inclination sensor 12, and a motor 13; the high-pressure pump 4, the laser rangefinder 8, the motor driver 10, the pressure sensor 11 and the inclination sensor 12, the cleaning disk 7, and the low-pass filter 14 are all electrically connected to the central processing unit 15.

[0059] Among them, four electromagnetic wheels 7 are connected to the robot body and placed on the four sides of the robot body; some pressure sensors 11 are placed in the electromagnetic wheel 9, and a groove is set every 45° on the rolling surface of the electromagnetic wheel. A pressure sensor is installed in each groove to collect the support reaction force between the electromagnetic wheel and the steel bridge. In addition, a pressure sensor 11 is set in the cleaning disk 7, and a groove is opened under the cone of the cleaning disk to embed the pressure sensor to collect the support reaction force between the cleaning disk and the steel bridge; the motor 13 is placed under the robot body and is connected to the electromagnetic wheel 9 through a rotating shaft to drive the electromagnetic wheel to move on the wall of the steel bridge; the motor driver 10 is placed on the support plate above the robot body, connected to the electromagnetic wheel 7 and the motor 13, and is used to receive the control signal of the control system to output current to the electromagnetic wheel and feed back the real-time current value of the electromagnet to the control system and control the start of the motor;

[0060] The low-pass filter 14 is placed on the workbench above the robot body and is used to collect noise data and reduce the impact of noise on the control system;

[0061] Two laser rangefinders 8 are provided. One laser rangefinder 8 is provided at the front of the robot body to monitor obstacles ahead. The other laser rangefinder is provided on the lower truss at the front of the robot body, facing the steel bridge wall, to monitor whether the robot body has moved into the transition area and detect whether there is a risk of stepping into the air. If the measured value of the laser rangefinder undergoes a large sudden change, it is considered that there is a risk of stepping into the air. If the change is small, it is considered to be in the transition area.

[0062] Two inclination sensors 12 are placed on the truss below the robot body to measure the inclination angle of the working surface of the steel bridge and the angle between the two walls of the transition zone; the detection head of one inclination sensor 12 faces downward to measure the wall angle, and the detection head of the other inclination sensor 12 faces the direction of travel to measure the angle θ of the transition zone.

[0063] The control system is used to receive the collected data and control the current of the electromagnetic wheel to adjust the electromagnetic adsorption force.

[0064] In the present invention, the steel bridge can be composed of multiple components such as wing plates and webs, and there are transition zones between adjacent different components. The robot of the present application can clean the entire steel bridge and can adapt to cleaning work at different positions.

[0065] The adaptive adsorption control method of the steel bridge rust removal robot provided in this embodiment includes the following steps:

[0066] First, the rust removal robot is started, and then the motor driver 10 is started to adjust the current of the electromagnet to ensure that the rust removal robot is closely attached to the surface of the steel bridge.

[0067] Then, the pressure sensor 11 is used to collect the real-time support reaction force data between the rust removal robot and the steel bridge surface, as well as the support reaction force between the cleaning plate and the steel bridge. The laser rangefinder 8 collects the real-time distance data between the robot's electromagnet and the steel bridge surface. The inclination sensor 12 collects the inclination angle data of the steel bridge surface.

[0068] Then start the low-pass filter to collect noise data and perform noise reduction processing;

[0069] Finally, the real-time data collected by all pressure sensors 11, laser rangefinder 8, tilt sensor 12 and low-pass filter 14 are transmitted to the central processing unit of the control system, and data are continuously collected at a predetermined time period.

[0070] The steel bridge is divided into an inclined wall working condition and a transition zone working condition caused by the intersection of two inclined walls. In the transition zone working condition, there is a certain angle between the two inclined walls. In each working condition, the two electromagnetic wheels at the front end are set as electromagnetic wheels in the rust zone, and the two electromagnetic wheels at the rear end are set as electromagnetic wheels in the non-rust zone. The electromagnetic driving force and electromagnetic adsorption force of the two electromagnetic wheels in the same area are the same. Taking the robot's walking direction as the front, the electromagnetic wheel on the left side of the rust zone is electromagnetic wheel No. 1, the electromagnetic wheel on the right side is electromagnetic wheel No. 2, the electromagnetic wheel on the left side of the non-rust zone is electromagnetic wheel No. 4, and the electromagnetic wheel on the right side is electromagnetic wheel No. 3.

[0071] 1. Inclined Wall Condition: The following example calculates rust removal from bottom to top on an inclined wall, assuming that water loss during the rust removal process is negligible. The central processing unit is electrically connected to the cleaning disk and high-pressure pump, and the adsorption pressure and water pressure of the cleaning disk are both set to constant.

[0072] Step 1.1, first analyze the rust removal state of walking on the steel bridge wall, such as Figure 3 The mechanical analysis diagram shown in the figure takes into account that the rust removal robot can be safely adsorbed on the wall and walk without sliding. It can prevent sliding when formula (1) is satisfied:

[0073] Fv1 +F v2 +F v3 +F v4 ≥f1+f2+f3+f4+f5+G.cosα=J1 (1)

[0074] f1=μ1·N1 f2=μ2·N2 f3=μ3·N3 f4=μ4·N4 f5=μ5·N5 (2)

[0075] Among them F v1 、F v2 is the driving force of the two electromagnetic wheels located in the rusted area, F v3 、F v4 is the driving force of the two electromagnetic wheels in the non-corrosion area, f1 and f2 are the friction forces of the two electromagnetic wheels in the rust area, f3 and f4 are the friction forces of the two electromagnetic wheels in the non-corrosion area, and f5 is the friction force of the cleaning disk; μ1, μ2, μ3, and μ4 are the friction coefficients between the four electromagnetic wheels and the steel plate, and μ5 is the friction coefficient between the cleaning disk and the steel bridge wall. The specific values ​​of the friction coefficients are obtained by measurements before the experiment and are known values ​​during calculation; N1 and N2 are the support reaction forces between the two electromagnetic wheels in the rust area and the steel bridge wall, N3 and N4 are the support reaction forces between the two electromagnetic wheels in the non-corrosion area and the steel bridge wall, and N5 is the support reaction force on the cleaning disk. The value of the support reaction force is obtained by detecting the corresponding pressure sensor; α is the inclination angle of the steel bridge wall to the vertical direction, which is detected by the inclination sensor; G is the weight of the robot (measured in terms of initial weight, which is the initial measured value).

[0076] Furthermore, the sum of the driving forces of the four electromagnetic wheels is set to the critical value of J1, and the driving forces of the four electromagnetic wheels are set to be equal when on the same inclined wall, so that the robot can walk normally on the wall. The driving force of each electromagnetic wheel is:

[0077]

[0078] Step 1.2: Establish the equilibrium equations of electromagnetic adsorption force, support reaction force, air pressure adsorption force, and jet recoil force in the direction perpendicular to the inclined wall of the steel bridge:

[0079] F c1 +F c2 +F c3 +F c4 +F N =N1+N2+N3+N4+N5+F n +G.sinα=J2 (3)

[0080] F c1 =F c2 , F c3 =F c4 (4)

[0081] Among them F c1 , F c2 is the electromagnetic attraction force between the two electromagnetic wheels in the rusted area and the steel bridge wall, F c3 , F c4 is the electromagnetic attraction force between the two electromagnetic wheels in the non-corroded area and the steel bridge wall, F m is the water jet recoil force, F N Air pressure adsorption for cleaning disk.

[0082] Furthermore, when the rust removal liquid is pure water, the water jet recoil force F is obtained from the high-pressure water flow and high-pressure water pressure. m :

[0083]

[0084] Where, Q is the high-pressure water flow rate, unit L / min, which is controlled by the high-pressure pump; p0 is the high-pressure water pressure (set value), unit MPa; F m The unit is N. When calculating, Q and p0 are substituted into the above units, and the value of the water jet recoil force is obtained through the formula.

[0085] The air pressure adsorption force of the cleaning disk can be further obtained from the cleaning disk structure and the negative pressure of the cleaning disk:

[0086] F N =1 / 4.π.d 2 .p

[0087] Where d is the diameter of the cleaning disk, in m; p is the negative pressure of the cleaning disk, in Pa, which is a set constant; F N The unit is N. When the negative pressure of the cleaning disk is a constant value, the pressure adsorption force of the cleaning disk is F. N Also a constant.

[0088] The relationship between the electromagnetic adsorption force of the electromagnetic wheel in the rusted area and the electromagnetic adsorption force of the electromagnetic wheel in the non-rusted area under the force balance state can be obtained through formula (3).

[0089] Step 1.3: To ensure the robot can work safely on the steel bridge wall without tipping over, perform an anti-tipover analysis to achieve moment balance:

[0090]

[0091] Among them, when the robot overturns, the center of gravity is far away from the No. 3 electromagnetic wheel. Assuming that only the No. 3 electromagnetic wheel is free, the overturning angle is not considered. The contact point between the electromagnetic wheel and the inclined wall of the steel bridge before it is free is recorded as the overturning point. H is the distance from the projection point of the center of gravity on the inclined wall of the steel bridge to the overturning point. d1, d2, d3, and d4 are the distances from the projection point of the lowest point of the four electromagnetic wheels on the inclined wall of the steel bridge to the overturning point. d5 is the distance from the projection point of the center point of the cleaning disk on the inclined wall of the steel bridge to the overturning point. are the angles between the lines connecting the projection points of the four electromagnetic wheels and the overturning points and the direction of the friction force, It is the angle between the line connecting the projection point of the center point of the cleaning disc and the overturning point and the direction of the friction force (H, d1, d2, d3, d4, is the test value before the experiment); f i , i = integers from 1 to 5, representing the friction forces on the four electromagnetic wheels and the cleaning disc respectively; Obtained according to formula (2).

[0092] The electromagnetic adsorption force value range of the electromagnetic wheel in the rusted area and the non-rusted area is calculated by combining formulas (3)-(5) to satisfy the torque balance equation and force balance equation.

[0093]

[0094] According to the above range of values, the minimum value of the electromagnetic adsorption force is determined as F c1 The minimum value is taken as the theoretical value F of the electromagnetic adsorption force of the electromagnetic wheel in the rusted area. cs1 , with F c3 The minimum value is taken as the electromagnetic adsorption force theory F of the electromagnetic wheel in the non-corroded area cs2 .

[0095] 2. Transition zone working conditions:

[0096] Step 2.1, analyze the theoretical value of electromagnetic adsorption force of the rust removal robot in the transition state of the steel bridge wall, such as Figure 4 The mechanical analysis diagram shown above first performs mechanical analysis in the direction parallel to the inclined wall before the transition:

[0097] F v11 +F v12 +F v13 +F v14 -(F v21 +F v22 -f 21 -f 22 )cosθ+(F c21 +F c22 -N 11 -N 21 )sinθ=Gcosα+f11 +f 12 +f 13 +f 14 +f5 (6)

[0098] f 21 =f 22 , F c21 =F c22 , N 21 =N 22 , f 11 =f 12 , f 13 =f 14

[0099] Among them, θ is the angle of wall transition, α is the angle between the inclined wall and the vertical direction before transition (the angles are collected by the tilt sensor), F v11 、F v12 is the driving force between the two electromagnetic wheels in the rust zone and the inclined wall before the transition, F v13 、F v14 is the driving force between the two electromagnetic wheels in the non-corroded area and the inclined wall before the transition, F v21 、F v22 is the driving force between the two electromagnetic wheels in the rusted area and the inclined wall after the transition, F c21 、F c22 is the electromagnetic adsorption force between the electromagnetic wheel in the rusted area and the inclined wall after the transition, f 11 、f 12 is the friction force between the two electromagnetic wheels in the rusted area and the inclined wall before the transition, f 13 、f 14 is the friction force between the two electromagnetic wheels in the non-corroded area and the inclined wall before the transition, f 21 、f 22 is the friction force between the two electromagnetic wheels in the rusted area and the inclined wall after the transition, and f5 is the friction force between the cleaning disk and the inclined wall before the transition; in the subscripts of the above two numbers, the first number represents before and after the transition, and the second number represents the corresponding four electromagnetic wheels, such as F v11 The first 1 indicates before transition, and the second 1 indicates electromagnetic wheel No. 1, so F v11 It represents the driving force between electromagnetic wheel No. 1 (rusted area) and the inclined wall before transition.

[0100] Step 2.2: Perform mechanical analysis perpendicular to the inclined wall before the transition, and establish the equilibrium equations of electromagnetic adsorption force, support reaction force, air pressure adsorption force, and jet recoil force on the inclined wall before the transition:

[0101] F c11 +F c12 +F c13 +F c14+F N +(f 21 +f 22 -F v21 -F v22 )sinθ=(N 11 +N 12 +N 13 +N 14 +N5+F m )+G sinα+(F c21 +F c22 -N 21 -N 22 )cosθ (7)

[0102] F c11 =F c12 , F c13 =F c14

[0103] Among them, F c11 、F c12 is the electromagnetic adsorption force between the two electromagnetic wheels in the rust zone and the inclined wall before the transition, F c13 、F c14 is the electromagnetic adsorption force between the two electromagnetic wheels in the non-corrosion area and the inclined wall before the transition, N 11 、N 12 is the reaction force between the two electromagnetic wheels in the rusted area and the inclined wall before the transition, N 13 、N 14 is the reaction force between the two electromagnetic wheels in the non-corroded area and the inclined wall before the transition, N5 is the reaction force on the cleaning plate, and F m is the water jet recoil force, F N It is the air pressure adsorption force of the cleaning disk; the support and reaction forces are measured by pressure sensors.

[0104] Step 2.3: Perform mechanical analysis along the parallel direction of the inclined wall after the transition:

[0105] (N 11 +N 12 +N 13 +N 14 +N5+F m )sinθ+(f 11 +f 12 +f 13 +f 14 +f5-f v11 -f v12 -f v13 -f v14 )cosθ=(F c11 +F c12 +F c13 +F c14+F N )sinθ+f 21 +f 22 -(f v21 +f v22 )-G cos(α-θ) (8)

[0106] Step 2.4: Perform mechanical analysis perpendicular to the target wall after the transition:

[0107] (f 11 +f 12 +f 13 +f 14 +f5-f v11 -f v12 -f v13 -f v14 )sinθ-(N 11 +N 12 +N 13 +N 14 +N5+F m )cosθ-G sin(α-θ)+N 21 +N 22 =(F c11 +F c12 +F c13 +F c14 +F N )cosθ+F c21 +F c22 (9)

[0108] Further, the friction force is equal to the product of the support reaction force and the friction coefficient, and the following formula can be obtained:

[0109] f 11 =μ1·N 11 f 12 =μ2·N 12 f 13 =μ3·N 13 f 14 =μ4·N 14 f5=μ5·N5 f 21 =μ1·N 21 f 22 =μ2·N 22 (10)

[0110] Among them, μ1, μ2, μ3, and μ4 are the friction coefficients between the four electromagnetic wheels and the steel plate, and μ5 is the friction coefficient between the cleaning disk and the steel bridge wall. The friction coefficients are all obtained by measurements before the experiment. The friction coefficients in the rusted area and the non-rusted area are different and are all set as constants.

[0111] Considering the limit state of wall transition, N 11 、N12 、f 11 、f 12 etc. are all 0, and F can be obtained from formulas (6)-(10) c11 、F c21 、F c13 Since the electromagnetic adsorption force of the electromagnetic wheel in the rusted area on the inclined wall before and after the transition is the same, F c11 、F c21 The larger value of the two is taken as the theoretical value of electromagnetic adsorption force of the rusted area of ​​the wall transition F ct1 , and take F c13 The theoretical value of electromagnetic adsorption force F in the non-corrosion zone of the wall transition ct2 .

[0112]

[0113] The above calculations yielded the theoretical values ​​of the electromagnetic adsorption forces of the four electromagnetic wheels required for the rust removal robot to move and remove rust on the wall of a steel bridge with different inclination angles and for the wall transition.

[0114] As the rust removal operation proceeds, part of the electromagnetic wheels move on the rusted area, and the other part moves on the steel bridge wall after rust removal. The electromagnetic wheels in the rusted area are adsorbed on the surface of the underusted steel bridge, and the electromagnetic wheels in the non-rusted area are adsorbed on the surface of the steel bridge after rust removal. The existence of rust greatly affects the electromagnetic adsorption force of the electromagnetic wheels in the rusted area of ​​the rust removal robot. Therefore, it is necessary to calculate the theoretical value F of the electromagnetic adsorption force of the electromagnetic wheels in the rusted area under the two working conditions (inclined wall or transition area) obtained above. cs1 、F ct1 To this end, a relationship between the corrosion thickness t and the corrosion magnetic permeability μ is proposed. r The characteristic parameter γ of the electromagnetic wheel in the rusted area is adjusted accordingly.

[0115]

[0116] in, is the ratio of the relative magnetic permeability of the original steel plate to the composite relative magnetic permeability of the steel plate and rust, β is the ratio of the change in electromagnetic adsorption force caused by the increase in the electromagnetic adsorption gap δ caused by the rust thickness, γ is a characteristic parameter related to the rust thickness and rust magnetic permeability of the steel bridge surface, μ r1 is the relative magnetic permeability of the steel bridge, t1 is the thickness of the steel plate, μ r2is the relative permeability after rusting, t2 is the rust thickness, b is the ratio of the rust thickness to the steel plate thickness (0 < b < 1%), c is the clearance coefficient caused by rust (0 < c < 1), F1 is the theoretical value of the electromagnetic adsorption force of the electromagnetic wheel located in the rust area during rust removal on the inclined wall surface after adjustment, and F2 is the theoretical value of the electromagnetic adsorption force of the electromagnetic wheel located in the rust area during wall surface transition after adjustment.

[0117] Furthermore, the theoretical values of the electromagnetic adsorption forces F1 and F2, F cs2 and F ct2 of the electromagnetic wheels in the rust area and non-rust area under the two working conditions. By adjusting the current, the robot can always maintain the above theoretical values and can perform adaptive adsorption.

[0118] Specifically, the corresponding theoretical current values I1, I2, I3, and I4 are calculated through the electromagnetic adsorption force formula as the current target values of their respective adaptive adsorption control algorithms. The electromagnetic adsorption force formula is as follows:

[0119]

[0120] Among them, F is the electromagnetic adsorption force, μ0 is the magnetic permeability constant of vacuum, N is the number of turns of the coil, I is the current of the actual electromagnet when the robot adsorbs, A is the contact area between the electromagnetic wheel and the steel bridge, and δ is the clearance between the lowermost electromagnet in the electromagnetic wheel and the working surface of the steel bridge, which is a constant.

[0121] Furthermore, I1 and I2 are respectively used as the current target values I t ' of the electromagnetic wheels located in the rust area for the adaptive adsorption control of the electromagnetic adsorption force of the rust removal robot under the two working conditions, and I3 and I4 are respectively used as the current target values I t of the electromagnetic wheels located in the non-rust area for the adaptive adsorption control of the electromagnetic adsorption force of the rust removal robot under the two working conditions.

[0122] Furthermore, the adaptive adsorption control is carried out using the incremental Simpson-PID control algorithm. Preferably, the incremental Simpson-PID control algorithm is used to control the current adjustment amount of the current target values in the rust area and non-rust area, thereby controlling the magnitude of the electromagnetic adsorption force. The incremental Simpson-PID control algorithm uses parabolic error for value extraction, which improves the accuracy of the integral term; in addition, a low-pass filter is introduced to reduce the influence of noise on the differential operation of the PID controller, which improves the accuracy of the differential term and improves the overall calculation accuracy of the current adjustment amount.

[0123] The original formula for the current regulation of the two electromagnetic wheels located in the non-rust area by the conventional PID control algorithm is:

[0124] The incremental Simpson-PID control algorithm is used to control the current of the two electromagnetic wheels in the non-corrosion area:

[0125]

[0126] in

[0127]

[0128] ΔI k K is the current adjustment value of the electromagnetic wheel located in the non-rusting area output by the control system of the rust removal robot. a1 is the reference value of the proportional coefficient, K b1 is the reference value of the integral coefficient, K c1 is the differential coefficient reference value, e k+1 is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the k+1th moment, e k is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the kth moment, e k-1 is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the k-1th moment, I t is the target current value of the electromagnetic wheel in the non-corrosion area, I m is the actual value of the electromagnetic wheel current in the non-corroded area, k+1 represents the sampling at the k+1th moment, k represents the kth moment, k-1 represents the k-1th moment, n is the number of moments of the final sampling of the system, τ is the filter time constant, and s is the complex frequency variable in the Laplace transform;

[0129] By inputting the error value e between the current target value and the actual current value of the electromagnetic wheel in the non-corrosion area k , calculate the electromagnetic wheel current adjustment value ΔI in the non-corrosion area k The electromagnetic adsorption force of the electromagnetic wheel in the non-corroded area is adjusted by adjusting the current output by the central processing unit.

[0130] Furthermore, the proportional, integral, and differential coefficients of the electromagnetic wheel adaptive adsorption control algorithm in the corroded area are dynamically adjusted using a nonlinear function g(ε) based on the relative error of the electromagnetic wheel current in the corroded area. The adjusted proportional coefficient maintains a relatively large value for a long time when the error is large, enabling rapid regulation; while it remains at a low level when the error is small, achieving long-term stable regulation. The adjusted integral coefficient accelerates the integral action to reduce steady-state error when the error is small, due to a small proportional adjustment. When the error is large, the adjusted integral coefficient maintains a low value when the proportional adjustment is large, avoiding system oscillation or overshoot caused by excessive action. The adjusted differential coefficient maintains a high value for a long time when the error is large, effectively suppressing overshoot and accelerating system stabilization to the target value; when the error is small, the adjusted differential coefficient maintains a low level for a long time to avoid oscillation or overshoot in the system response. Furthermore, these adjusted coefficients exhibit more stable performance with error changes, reducing oscillation or divergence caused by excessively large or small error steps, significantly improving stability. The linear function g(ε) and the adjusted proportional, integral, and differential coefficients are as follows:

[0131]

[0132] Among them, I t ' is the target value of the electromagnetic wheel current in the rusted area, I m ' is the actual value of the electromagnetic wheel current in the rusted area, ε represents the relative value of the error, which is I t 'with I m 'The difference between t 'ratio, q is a constant between 0 and 1, K a1 is the reference value of the proportional coefficient, K b1 is the reference value of the integral coefficient, K c1 is the reference value of the differential coefficient, τ is the filter time constant, and s is the complex frequency variable in the Laplace transform.

[0133] By inputting the error value e between the target value and the actual value of the electromagnetic wheel current in the rusted area k ', calculate the current adjustment value of the electromagnetic wheel located in the rusted area, and adjust the electromagnetic adsorption force of the electromagnetic wheel located in the rusted area by outputting the current adjustment amount through the central control unit.

[0134]

[0135] in

[0136]

[0137] ΔI k ' is the current adjustment of the electromagnetic wheel located in the rusted area calculated by the control system of the rust removal robot, K a(ε) is the proportional control coefficient of the electromagnetic wheel current in the rusted area, K b (ε) is the integral control coefficient of the electromagnetic wheel current regulation in the rusted area, K c (ε) is the differential control coefficient of the electromagnetic wheel current regulation in the rusted area, e k+1 ' is the real-time error value of the electromagnetic wheel in the rusted area sampled at the k+1th moment, e k ' is the real-time error value of the electromagnetic wheel in the rusted area sampled at the kth moment, e k-1 ' is the real-time error value of the electromagnetic wheel in the rusted area sampled at the k-1th moment, I t ' is the target current value of the electromagnetic wheel located in the rusted area, I m ' is the actual value of the electromagnetic wheel current in the rusted area, τ is the filter time constant, s is the complex frequency variable in the Laplace transform, k+1 represents the k+1th moment, k represents the kth moment, k-1 represents the k-1th moment, and n is the number of moments at which the system is finally sampled.

[0138] Through continuous adjustment of adaptive adsorption control, the actual value of the electromagnetic wheel gradually approaches and stabilizes near the target value, thereby accurately adjusting the magnetic adsorption force of the electromagnetic wheel to ensure that the rust removal robot is firmly adsorbed on the surface of the steel bridge.

[0139] Example 2

[0140] The adaptive adsorption control method of the steel bridge rust removal robot in this embodiment includes the following steps:

[0141] Step 1: First start the rust removal robot, then start the motor driver to adjust the current of the electromagnetic wheel to ensure that the rust removal robot is tightly attached to the surface of the steel bridge.

[0142] Step 2: Use the inclination sensor to accurately obtain the angle data of the steel bridge wall, the pressure sensor to collect the support reaction force data between the rust removal robot and the steel bridge surface in real time, and the low-pass filter to collect noise data and perform noise reduction processing.

[0143] Step 3: The collected data is transmitted to the central processing unit of the control system for processing and the theoretical value of the electromagnetic adsorption force of the electromagnetic wheel located in the rusted area and the non-rusted area for moving rust removal on the wall with different inclination angles and for the inclined wall and transition zone is calculated.

[0144] Step 4: The theoretical current value calculated based on the theoretical value of the electromagnetic adsorption force of the electromagnetic wheel in the non-corroded area is used as the target value of the adaptive adsorption control of the electromagnetic wheel in the non-corroded area. The theoretical current value calculated after adjusting the theoretical value of the electromagnetic adsorption force of the electromagnetic wheel in the corroded area using the characteristic parameter γ is used as the target value of the adaptive adsorption control algorithm of the electromagnetic wheel in the corroded area.

[0145] Step 5: Use the motor driver to obtain the current value data of the electromagnetic wheels located in the non-rusted area and the rusted area of ​​the rust removal robot in real time, and use this current value as the actual current value of each.

[0146] Step 6: Determine whether the target value and actual value of the electromagnetic wheel in the non-corrosion area are equal. If they are equal, it indicates that the current adjustment value of the electromagnetic wheel in the non-corrosion area is 0. If they are not equal, calculate the error between the target value and the actual value of the electromagnetic wheel current in the non-corrosion area, use this error value as input, and calculate its current adjustment value in the adaptive adsorption control.

[0147]

[0148] in

[0149]

[0150] ΔI k K is the current adjustment value of the electromagnetic wheel located in the non-rusting area output by the control system of the rust removal robot. a1 is the reference value of the proportional coefficient, K b1 is the reference value of the integral coefficient, K c1 is the differential coefficient reference value, e k+1 is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the k+1th moment, e k is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the kth moment, e k-1 is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the k-1th moment, I t is the target current value of the electromagnetic wheel in the non-corrosion area, I m is the actual value of the electromagnetic wheel current in the non-corroded area, k+1 represents the sampling at the k+1th moment, k represents the kth moment, k-1 represents the k-1th moment, n is the number of moments of the final sampling of the system, τ is the filter time constant, and s is the complex frequency variable in the Laplace transform.

[0151] Step 7: Determine whether the target value and actual value of the electromagnetic wheel current in the rusted area are equal. If they are equal, it indicates that the current adjustment value of the electromagnetic wheel in the rusted area is 0. If they are not equal, calculate the error between the target value and the actual value of the electromagnetic wheel current in the rusted area, and then dynamically adjust the proportional, integral and differential coefficients in the adaptive adsorption control of the electromagnetic wheel in the rusted area using a nonlinear function according to the relative error value. Finally, use this error value as input to calculate its current adjustment value through adaptive adsorption control.

[0152]

[0153] in

[0154]

[0155] ΔI k ' is the current adjustment of the electromagnetic wheel located in the rusted area calculated by the control system of the rust removal robot, K a (ε) is the proportional control coefficient of the electromagnetic wheel current in the rusted area, K b (ε) is the integral control coefficient of the electromagnetic wheel current regulation in the rusted area, K c (ε) is the differential control coefficient of the electromagnetic wheel current regulation in the rusted area, e k+1 ' is the real-time error value of the electromagnetic wheel in the rusted area sampled at the k+1th moment, e k ' is the real-time error value of the electromagnetic wheel in the rusted area sampled at the kth moment, e k-1 ' is the real-time error value of the electromagnetic wheel in the rusted area sampled at the k-1th moment, I t ' is the target current value of the electromagnetic wheel located in the rusted area, I m ' is the actual value of the electromagnetic wheel current in the rusted area, τ is the filter time constant, s is the complex frequency variable in the Laplace transform, k+1 represents the k+1th moment, k represents the kth moment, k-1 represents the k-1th moment, and n is the number of moments at which the system is finally sampled.

[0156] Step 8: The control system converts the electromagnetic wheel current adjustment value calculated by the adaptive adsorption control into a control signal and transmits it to the motor driver. By controlling the motor driver, the electromagnetic wheel current is adjusted, and thus the electromagnetic adsorption force is adjusted. The electromagnetic adsorption force is continuously adjusted by the adaptive adsorption control to achieve the theoretical electromagnetic adsorption force value.

[0157] The adaptive adsorption control adopts Simpson-PID control algorithm.

[0158] Through the above method, the rust removal robot can be stably adsorbed to the wall of the steel bridge and the electromagnetic adsorption force can be adaptively controlled during the mobile rust removal operation and wall transition of the rust removal robot. Even if the electromagnetic wheel located in the rusted area is driving in a severely rusted area, its own current can be quickly adjusted in a short time so that the electromagnetic adsorption force is quickly adjusted to the target value, thereby achieving stable adsorption of the rust removal robot.

[0159] Example 3

[0160] The process of adaptive adsorption control in this embodiment is:

[0161] The theoretical values ​​of the electromagnetic forces of the electromagnetic wheels located in the rusted area and the non-rusted area are calculated based on the mechanical equilibrium equations of the rust removal robot in the two states of moving rust removal on the steel bridge wall and wall transition.

[0162] The theoretical value of the current is calculated from the theoretical value of the respective electromagnetic forces;

[0163] The current theoretical value calculated from the electromagnetic force theoretical value of the electromagnetic wheel in the non-corrosion area is used as its current target value, and the current theoretical value adjusted by the characteristic parameter γ from the electromagnetic force theoretical value of the electromagnetic wheel in the corrosion area is used as its current target value;

[0164] Calculate the error between the current target value and the actual value;

[0165] A relative error value obtained by applying the ratio of the error value to the current target value is used to adjust the proportional, integral and differential coefficients of the adaptive control algorithm of the electromagnetic wheel located in the rusted area.

[0166] Taking the above error value as input, the adaptive control algorithm is used to calculate the current adjustment values ​​of the electromagnetic wheel located in the rusted area and the electromagnetic wheel located in the non-rusted area under the two working conditions of mobile rust removal and wall transition on the steel bridge wall.

[0167] This project applies electromagnetic adsorption technology to bridge maintenance and inspection. Adaptive adsorption control enables stable adsorption between the electromagnetic adsorption rust removal robot and different steel bridge surfaces. This allows the electromagnetic adsorption rust removal robot to maintain close contact with the steel bridge during mobile rust removal, ensuring safe adsorption operations.

[0168] The above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application.

[0169] Any matters not described in the present invention are applicable to the prior art.

Claims

1. An adaptive adsorption control method for a steel bridge rust removal robot, characterized in that: The rust removal robot uses four electromagnetic wheels for walking. The front two electromagnetic wheels are located in the rusted area and provide the same electromagnetic driving force. The rear two electromagnetic wheels are located in the non-rusted area and provide the same electromagnetic driving force. A cleaning disk is provided in the middle of the robot. The cleaning disk is used to contact the steel bridge wall to remove rust from the steel bridge wall. Pressure sensors for measuring support reaction force are installed on the four electromagnetic wheels and the cleaning disk. The rust removal robot is also equipped with an inclination sensor for measuring the inclination angle of the working surface of the steel bridge and the angle of the transition wall, and a laser rangefinder for detecting whether it is a transition wall. The adaptive control method includes the following steps: When the rust removal robot performs rust removal on the steel bridge wall, one part of the electromagnetic wheel moves on the rusted area, while the other part of the electromagnetic wheel moves on the wall after rust removal. The steel bridge wall is divided into an inclined wall working condition and a transition zone working condition caused by the intersection of two inclined walls. In the transition zone working condition, there is an angle between the two inclined walls. For the inclined wall working condition, when the rust removal robot moves and removes rust on the wall of the steel bridge with different inclination angles, the force balance equation in the direction perpendicular to the inclined wall of the steel bridge is considered, which ensures that the rust removal robot can safely adsorb on the wall and walk without sliding, as well as the moment balance equation that ensures that the robot can safely work on the steel bridge wall without overturning. The electromagnetic adsorption force value range of the electromagnetic wheel in the rusted area and the non-rusted area is obtained; the minimum value of the electromagnetic adsorption force of the electromagnetic wheel in the rusted area is taken as the theoretical value F of the electromagnetic adsorption force of the electromagnetic wheel in the rusted area. cs1 The minimum value of the electromagnetic adsorption force of the electromagnetic wheel in the non-corrosion area is taken as the theoretical value of the electromagnetic adsorption force of the electromagnetic wheel in the non-corrosion area F cs2 ; For the transition zone working condition, the rust removal robot performs wall-moving rust removal in the transition state of the steel bridge wall. The force balance in the parallel direction of the inclined wall before the transition and the force balance in the direction perpendicular to the inclined wall before the transition, the force balance in the parallel direction of the inclined wall after the transition and the force balance in the direction perpendicular to the target wall after the transition are considered respectively. The theoretical value F of the electromagnetic adsorption force of the electromagnetic wheel in the rusted zone of the wall transition is obtained. ct1 Theoretical value of electromagnetic adsorption force F in the non-corroded area transitioning to the wall ct2 ; The theoretical values ​​of electromagnetic adsorption force of electromagnetic wheels in the rusted and non-rusted areas under different working conditions are used to calculate their respective theoretical current values, and the theoretical current values ​​are used as the current target values ​​of the PID control algorithm. The error between the actual current value and the target current value of the electromagnetic wheel in different areas under different working conditions is calculated, and the error value is input into the PID control algorithm. The PID control algorithm is used to adjust the actual current value of the corresponding electromagnetic wheel in real time, thereby realizing real-time control of the electromagnetic adsorption force of the electromagnetic wheel.

2. The adaptive adsorption control method according to claim 1, characterized in that: The theoretical value of the electromagnetic adsorption force of the electromagnetic wheel located in the rusted area is corrected according to the following formula: Where F1 and F2 are the corrected theoretical values ​​of the electromagnetic adsorption force of the electromagnetic wheel in the rusted area under the inclined wall working condition and the transition zone working condition, respectively; γ is a characteristic parameter related to the rust thickness and rust magnetic permeability of the steel bridge surface, which is obtained according to the following formula: Among them, is the ratio of the relative permeability of the original steel plate to the composite relative permeability of the steel plate and rust, and β is the ratio of the change in the electromagnetic adsorption force caused by the increase in the electromagnetic adsorption force gap δ caused by the rust thickness; c is the gap coefficient caused by rust, 0 < c < 1; b is the ratio of the rust thickness to the steel plate thickness, 0 < b < 1%; μ r1 is the relative permeability of the steel bridge; μ r2 is the relative permeability after rust; t is the rust thickness; The respective current theoretical values ​​of F1 and F2 are calculated, and then the PID control algorithm is used to adjust the electromagnetic adsorption force in real time.

3. The adaptive adsorption control method according to claim 1, characterized in that: The incremental Simpson-PID control algorithm is used to control the current regulation of the current target value in the corrosion area and the non-corrosion area. The incremental Simpson-PID control algorithm is used to control the current of the two electromagnetic wheels in the non-corrosion area: in ΔI k K is the current adjustment value of the electromagnetic wheel located in the non-rusting area output by the control system of the rust removal robot. a1 is the reference value of the proportional coefficient, K b1 is the reference value of the integral coefficient, K c1 is the differential coefficient reference value, e k+1 is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the k+1th moment, e k is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the kth moment, e k-1 is the real-time error value of the electromagnetic wheel in the non-corrosion area sampled at the k-1th moment, I t is the target current value of the electromagnetic wheel in the non-corrosion area, I m is the actual value of the electromagnetic wheel current in the non-corroded area, k+1 represents the sampling at the k+1th moment, k represents the kth moment, k-1 represents the k-1th moment, n is the number of moments of the final sampling of the system, i and j are ordinal numbers, τ is the filter time constant, and s is the complex frequency variable in the Laplace transform; The incremental Simpson-PID control algorithm controls the current of the two electromagnetic wheels in the rusted area as follows: in ΔI k ′ is the current adjustment of the electromagnetic wheel located in the rusted area calculated by the control system of the rust removal robot, K a (ε) is the proportional control coefficient of the electromagnetic wheel current in the rusted area, K b (ε) is the integral control coefficient of the electromagnetic wheel current regulation in the rusted area, K c (ε) is the differential control coefficient of the electromagnetic wheel current regulation in the rusted area, e k+1 ′ is the real-time error value of the electromagnetic wheel in the rusted area sampled at the k+1th moment, e k ′ is the real-time error value of the electromagnetic wheel in the rusted area sampled at the kth moment, e k-1 ′ is the real-time error value of the electromagnetic wheel in the rusted area sampled at the k-1th moment, I t ′ is the target current value of the electromagnetic wheel located in the rusted area, I m ′ is the actual value of the electromagnetic wheel current in the rusted area, τ is the filter time constant, s is the complex frequency variable in Laplace transform; ε is the relative error, 4. The adaptive adsorption control method according to claim 3, characterized in that: K a (ε), K b (ε), K c The expression of (ε) is: Among them, g(ε) is a nonlinear function of the relative error value ε, and the expression is: Where q is a constant between 0 and 1, and sign is a sign function.

5. A steel bridge rust removal robot, characterized in that: The rust removal robot adopts the adaptive adsorption control method described in any one of claims 1 to 4 to perform mobile rust removal control.

6. The steel bridge rust removal robot according to claim 5, characterized in that: The rust removal robot includes a control system, a high-pressure pump, a cleaning tray, a storage chamber, a laser rangefinder, an electromagnetic wheel, a motor driver, a pressure sensor, an inclination sensor, a motor, a low-pass filter and a robot body. The storage chamber is used to store the rust removal reagent; the high-pressure pump is used to pump the rust removal reagent in the storage chamber to the cleaning tray; Four electromagnetic wheels are connected to the robot body and are placed at the left front, right front, left rear, and right rear positions of the robot body; a groove is set every 45 degrees on the rolling surface of each electromagnetic wheel, and a pressure sensor is installed in each groove to collect the support reaction force between the electromagnetic wheel and the steel bridge. A groove is opened under the cone of the cleaning disk and a pressure sensor is embedded in it to collect the support reaction force between the cleaning disk and the steel bridge; the motor is placed under the robot body and connected to the electromagnetic wheel through a rotating shaft to drive the electromagnetic wheel to move on the wall of the steel bridge. Each electromagnetic wheel is controlled by a separate motor; the motor driver is placed on the support plate above the robot body and is connected to the electromagnetic wheel and the motor. It is used to receive the control signal of the control system to output current to the electromagnetic wheel and feedback the real-time current value of the electromagnet to the control system and control the start of the motor; Two laser rangefinders are installed. One laser rangefinder is set at the front of the robot body to monitor obstacles ahead. The other laser rangefinder is set on the lower truss at the front of the robot body, facing the steel bridge wall, to monitor whether the robot body moves to the transition area and detect whether there is a risk of stepping on the air. The inclination sensor is placed on the truss below the robot body to measure the inclination angle of the working surface of the steel bridge.

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