WO2023207007A1 - Abrasive water jet grinding system and method based on multi-axis drive control - Google Patents

Abstract

An abrasive water jet grinding system and method based on multi-axis drive control. The system comprises a grinding vehicle (1), a vehicle control system mounted on the grinding vehicle (1), a steel rail surface damage and front and rear profile detection system (2), a grinding servo drive system (3), an ultra-high pressure water treatment system (4), a water jet grinding system (5), a multi-channel grinding pressure and flow control system (6), and a waste water recovery and separation system (7). The water jet grinding system (5) comprises a grinding lifting mechanism (51), grinding performance mechanisms (52), and an abrasive supply mechanism (53), wherein the grinding performance mechanisms (52) on the same side are respectively used for realizing the rough-fine grinding of a steel rail, a three-axis full-servo drive mechanism is arranged on each grinding performance unit (57) of each grinding performance mechanism (52), and a plurality of grinding performance units (57) are controlled to be subjected to high-precision posture and position linkage by the grinding servo drive system (3), so as to fit with a profile of the steel rail, realizing profiling high-precision grinding of the steel rail; in addition, the high-precision multi-channel grinding pressure and flow control system (6) is designed in a channel of the grinding performance units (57), so as to control water pressure and flow of a water jet accurately.

Description

An abrasive water jet polishing system and method based on multi-axis drive control Technical field

The invention belongs to the technical field of water jet polishing, and more specifically, relates to an abrasive water jet polishing system and method based on multi-axis drive control.

Background technique

The rail is the most important component of the track system. It guides the train to move forward along the track. It relies on the rigidity of the track system structure to distribute the load exerted by the wheels and transmit it to the structure under the rail. The main function of the rail is to form a wheel-rail friction pair with the train wheels, provide the train with as continuous and smooth a bearing surface as possible, and guide the wheels to roll along the track. The wear of the rail surface is inevitable during the operation of subway vehicles. Due to various other complex factors, especially the uneven wheel-rail contact interface, the complex dynamic interaction between the wheel and rail will cause wheel-rail contact problems, causing rail wear. The process is often accompanied by various fatigue injuries.

In order to ensure the safety of trains and extend the service life of rails, the rails need to be ground and repaired to restore the optimal contour shape of the rails and improve the wheel-rail relationship. Currently, the rails are envelopingly polished using a grinding wheel grinding method. The heat generated during grinding is extremely high, which can easily burn the rails and cause continuous blue bands. During the grinding process, a large amount of dust, smoke, high-temperature debris, and sparks are produced, which pollutes the environment and poses a serious fire hazard. . Using ultra-high-pressure abrasive water jet to grind rails can effectively remove rail surface materials and achieve rail profile grinding. However, the rail jet grinding angle scheme makes the grinding accuracy uncontrollable, which can easily lead to mistaken grinding. When ultra-high-pressure water jet is used to polish rails, the recoil force of the water jet will affect the stability of the water jet and directly affect the grinding accuracy.

Contents of the invention

In view of the above defects or improvement needs of the existing technology, the present invention provides an abrasive water jet grinding system based on multi-axis drive control. By designing a vehicle-mounted intelligent abrasive water jet grinding system, multiple grinding water jet cutting heads are moved along the rails. Arranged longitudinally (in the direction of travel) and distributed transversely along the rail at different angles, the grinding angle of the grinding head and the water jet grinding pressure are accurately controllable, enabling multi-angle, high-precision grinding of the rail. A high-precision, multi-degree-of-freedom posture control system is designed on each group of water jets to achieve high-precision rail profile grinding, and a high-precision water jet pressure control system is designed in each group of water jet channels to achieve water jet pressure and flow. And precise control of grinding quantity quality and flow rate. It can solve the defects of the existing grinding wheel that easily burns the rails, causing continuous blue bands, environmental pollution during the grinding process, and large fire hazards, as well as the uncontrollable grinding accuracy of the existing ultra-high-pressure abrasive water jet grinding rails and the water jet recoil affecting the stability of the water jet. properties, which directly affects the grinding accuracy.

In order to achieve the above object, the present invention provides an abrasive water jet grinding system based on multi-axis drive control, including a grinding vehicle, a vehicle control system installed on the grinding vehicle, a rail surface damage and profile front and rear detection system, Grinding servo drive system, ultra-high pressure water treatment system, water jet grinding system, multi-channel grinding pressure flow control system and wastewater recycling and separation system; among them,

The water jet grinding system includes a grinding lifting mechanism, a grinding actuator provided on the grinding lifting mechanism, and an abrasive supply mechanism connected to the grinding actuator; the grinding lifting mechanism is a bilateral trapezoidal screw sliding mechanism, which can Realize the height control of the grinding actuator, and can realize position self-locking; each rail section is provided with at least one set of the grinding actuators, and the grinding actuators on the same side are respectively used to realize rough grinding and then fine grinding of the rail; The grinding execution mechanism includes a plurality of grinding execution units. The plurality of grinding execution units are arranged along the traveling direction of the rail and are laterally distributed along the rail at different angles. Each grinding execution unit is provided with a shaft full servo drive mechanism. The grinding angle of each grinding execution unit is controllable; the grinding servo drive system controls the high-precision posture linkage of multiple grinding execution units and fits the rail profile to achieve high profiling of the rail to be repaired. Precision grinding; and a high-precision multi-channel grinding pressure flow control system is designed in the grinding execution unit channel to achieve precise control of water jet pressure and flow.

Further, the multi-channel grinding pressure flow control system can accurately control the pressure and flow of the water jet in each channel, thereby improving grinding accuracy;

The multi-channel grinding pressure flow control system includes an ultra-high pressure water jet pressurized by a booster pump, a pilot relief valve connected to the hydraulic channel of the hydraulic pump on the grinding vehicle, and a pilot relief valve located on the The electromagnetic reversing valve of the remote control port and the first remote pressure regulating valve and the second remote pressure regulating valve that can be connected respectively through the electromagnetic reversing valve;

The electromagnetic reversing valve is a two-position two-way solenoid valve;

The pilot relief valve, the first remote pressure regulating valve and the second remote pressure regulating valve can all adjust the hydraulic pump outlet pressure.

Further, the grinding lifting mechanism includes a first lifting unit and a second lifting unit arranged in parallel and spaced apart from each other, and a grinding actuator connection bracket provided between the first lifting unit and the second lifting unit; The grinding actuator is installed on the grinding actuator connecting bracket; through the synchronous lifting of the first lifting unit and the second lifting unit, the lifting movement of the grinding actuator connecting bracket is realized, thereby driving the grinding actuator Lifting movement.

Further, the grinding actuator connecting bracket includes a grinding lifting mechanism connecting piece and a grinding actuator connecting piece;

The grinding actuator connecting piece is located at the lower end of the grinding lifting mechanism connecting piece, and the grinding actuator connecting piece and the grinding actuator connecting piece together form a rectangular frame structure;

A plurality of mounting holes for installing the grinding actuator are evenly spaced on the connecting piece of the grinding actuator.

Further, the structures of the first lifting unit and the second lifting unit are exactly the same;

The first lifting unit and the second lifting unit each include a vertical plate, a first fixed block and a second fixed block arranged on the vertical plate at parallel intervals from top to bottom, and vertically parallel spaced apart on the said vertical plate. The guide rod between the first fixed block and the second fixed block, the moving slider provided on the guide rod, the lifting drive motor provided on the top side of the vertical plate, the lifting drive motor output The coupling at the end and the ball screw located at the output end of the coupling;

The lifting drive motor and the coupling are arranged above the first fixed block in order from top to bottom;

The ball screw passes through the first fixed block and the moving slide block in sequence and is installed on the second fixed block;

The ball screw and the guide rod are arranged vertically and parallel to each other;

The moving slide block is fixedly connected to the nut of the ball screw, and the up and down spiral movement of the nut drives the up and down lifting movement of the moving slide block;

Further, both sides of the connecting piece of the grinding lifting mechanism are fixedly connected to the moving slide blocks on the first lifting unit and the second lifting unit respectively. Through the first lifting unit and the second lifting unit, The lifting drive motor starts, drives the coupling to rotate, and then drives the rotation of the ball screw into the up and down lifting motion of the moving slider, which then drives the up and down movement of the connecting bracket of the grinding actuator, and finally drives the The up and down movement of the grinding actuator enables precise control of the grinding height.

Further, the grinding execution mechanism includes a plurality of grinding execution units, and each grinding execution unit includes a first rotating motor, a second rotating motor, a third rotating motor, and a device arranged vertically to each other in sequence from top to bottom. The grinding water jet at the output end of the third rotating motor, the waste water recovery unit provided on the grinding water jet, and the mounting plate provided at the output end of the first rotating motor;

The mounting plate is used to fix the grinding execution unit and the grinding actuator connection piece.

Further, the controller that controls the full servo drive mechanism of the first rotating motor, the second rotating motor, and the third rotating motor adopts a variable gain joint controller with a nonlinear interference observer, and through a decentralized control strategy based on joint space, For separate control of single joints; a nonlinear interference observer is used to estimate the unknown external disturbance of the abrasive water jet polishing system, and the estimated results are used as system output compensation. On this basis, the joints are designed in combination with a variable gain sliding mode control algorithm. Controller to ensure the tracking accuracy and stability of the joint servo system, thereby achieving stable tracking of the position and posture of the polishing water jet;

Design the switching function of the variable gain joint controller according to the following formula:

In the formula,

is the derivation function of the switching function S; k(S) is an intermediate function and has no practical significance; α, β, k, η, and δ are variable gain joint system constants based on the nonlinear interference observer, 0＜α＜1, β>0, k>0, eta>0, 0<δ<1;

In the variable gain reaching law shown in the above formula, when the system operating trajectory is far away from the switching surface, that is, when the switching function modulus value |S| is relatively large, there is

It shows that the system can quickly approach the switching surface; when the system running trajectory is relatively close to the switching surface, there is

It shows that the system can effectively suppress chattering;

The variable gain joint controller is a multi-axis n-order single-input single-output nonlinear system, and its control law is as follows:

In the formula, x ₁ is the actual output position, x ₂ is the actual speed, x ₃ is the actual acceleration, x _n is the n-1 order derivative of the position, which generally does not represent a clear meaning, but is just to express the system state, X = [x ₁ ^x _{2 …} Uncertainty equivalent disturbances such as internal parameter perturbations and external disturbances of the output nonlinear system are bounded, that is, |d(t)|≤D≤+∞, and D is a constant;

Desired position for a given input,

are the desired position, velocity, and acceleration respectively. Let the tracking error of the multi-axis n-order single-input single-output nonlinear system be:

E＝ _Xd -X，

In the formula, E=[e ₁ e ₂ … e _n ] ^T ;

The switching function S can be expressed as:

S＝C·E＝c ₁ e ₁ +c ₂ e ₂ +…+e _n

In the formula, C = [c ₁ c ₂ … c _n-1 1], where c ₁ , c ₂ … c _n-1 are constants;

Then there is the derivation function of the switching function S:

From the above formula, the control law of the multi-axis n-order single-input single-output nonlinear system is

c is a constant, e _i is the tracking error, combined with the design method of the nonlinear interference observer, the observer is designed according to the following formula:

In the formula,

is the estimation error value of the nonlinear interference observer, z _f is the intermediate calculation function; p (x ₃ ) is the nonlinear function of the observer, L>0 is the coefficient of the nonlinear interference observer, satisfying

The observation error of the nonlinear interference observer is defined as:

Based on the analysis of interference error convergence, the estimated error value

After passing through the gain adjustment module, it is converted into the control input u _g at the input end. Taking the gain size as g, we have

When a suitable g value is given, the observer can well compensate for the total uncertainty perturbation of the system; here, it is assumed that

At this time there is

After adopting the nonlinear interference observer, the total uncertainty interference of the system is greatly reduced, from G to

Then the system state equation can be transformed into

Then the system output after compensation through the nonlinear interference observer is:

In the formula, Sgn is a universal symbolic function in mathematics.

Further, the rail surface damage and profile front and rear detection system includes a vehicle body front end detection device installed at the front end of the grinding vehicle and a vehicle body rear end detection device installed at the rear end of the grinding vehicle; the vehicle body front end Both the detection device and the vehicle body rear-end detection device are integrated with a 3D structured light detection system for detecting rail profile and surface defects;

The ultra-high pressure water treatment system includes a water tank and a booster pump installed on the grinding vehicle; the water jet grinding system is installed on the bottom of the grinding vehicle frame;

The wastewater recycling and separation system is used to recycle grinding wastewater and separate water from abrasives to achieve recycling of water resources.

Further, the grinding servo drive system includes a bogie assembly, an electrical cabinet, a driving traction transmission system, a cooling system and an air compressor provided on the grinding car; the air compressor is used to provide air systems for the grinding car. It provides power for the movement and at the same time provides power for abrasive transmission for the water jet grinding vehicle;

The abrasive supply mechanism includes a coarse abrasive tank and a fine abrasive tank provided on the air compressor. The coarse abrasive tank is connected to the grinding actuator through a coarse abrasive transmission channel and is used to realize rough grinding of the rail; The fine abrasive tank is connected to the grinding actuator through a fine abrasive transmission channel to achieve fine grinding of the rail;

The booster pump and the polishing actuator are connected through a polishing water transmission channel. The water in the water tank is pressurized by the booster pump to form ultra-high-pressure water, which is supplied to the polishing actuator through the polishing water transmission channel. Mechanism is supplied, and the water jet grinding pressure and flow rate are accurately controlled through the multi-channel grinding pressure flow control system.

Generally speaking, compared with the prior art, the above technical solutions conceived by the present invention can achieve the following beneficial effects:

(1) An abrasive water jet grinding system and method based on multi-axis drive control of the present invention. By designing a vehicle-mounted intelligent abrasive water jet grinding system, each rail section is provided with at least 2 sets of grinding actuators, and the grinding actuators on the same side are respectively It is used to realize rough grinding and then fine grinding of the rail; multiple grinding execution units of the grinding actuator are arranged along the direction of rail travel, and are distributed transversely along the rail at different angles. Each grinding execution unit is equipped with a 3-axis full-scale grinding actuator. The servo drive mechanism makes the grinding angle of each grinding execution unit controllable; the grinding lifting mechanism is designed as a bilateral trapezoidal screw sliding mechanism, which can realize the height control of the grinding actuator and realize position self-locking; through the grinding servo drive system 3. Control the high-precision posture linkage of multiple grinding execution units and fit the rail profile to achieve high-precision grinding of the rail to be repaired; and design a high-precision multi-channel grinding pressure flow control system in the grinding execution unit channel. Achieve precise control of water jet pressure and flow, thereby achieving multi-angle, high-precision grinding of rails. It can solve the defects of the existing grinding wheel that easily burns the rails, causing continuous blue bands, environmental pollution during the grinding process, and large fire hazards, as well as the uncontrollable grinding accuracy of the existing ultra-high-pressure abrasive water jet grinding rails and the water jet recoil affecting the stability of the water jet. properties, which directly affects the grinding accuracy.

(2) An abrasive water jet polishing system and method based on multi-axis drive control of the present invention. In order to improve the immunity and robustness of the drive system, the first rotating motor, the second rotating motor, and the third rotating motor are controlled. The controller of the full servo drive mechanism of the rotating motor adopts a variable gain joint controller with a nonlinear interference observer. Through a decentralized control strategy based on joint space, single joints are controlled separately; based on the basic idea of the interference observer, the nonlinear interference is used The observer (NDO) is used to estimate the unknown external disturbance of the abrasive water jet polishing system of the present invention, and the estimated result is used as the system output compensation. On this basis, the joint controller is designed in combination with the variable gain sliding mode control algorithm to ensure that The tracking accuracy and stability of the joint servo system enable stable tracking of the position and posture of the polishing water jet.

Description of drawings

Figure 1 is a schematic diagram of the overall structure of an abrasive water jet polishing system based on multi-axis drive control according to an embodiment of the present invention;

Figure 2 is a schematic structural diagram of a water jet polishing system based on a multi-axis drive control abrasive water jet polishing system according to an embodiment of the present invention;

Figure 3 is a schematic structural diagram of a polishing lifting mechanism of an abrasive water jet polishing system based on multi-axis drive control according to an embodiment of the present invention;

Figure 4 is a schematic structural diagram of the grinding actuator of an abrasive water jet grinding system based on multi-axis drive control according to an embodiment of the present invention;

Figure 5 is a schematic structural diagram of a polishing execution unit of an abrasive water jet polishing system based on multi-axis drive control according to an embodiment of the present invention;

Figure 6 is a schematic structural diagram of a multi-channel grinding pressure flow control system of an abrasive water jet grinding system based on multi-axis drive control according to an embodiment of the present invention;

Figure 7 is a schematic diagram of the decentralized control structure based on joint space of an abrasive water jet polishing system based on multi-axis drive control according to an embodiment of the present invention;

Figure 8 is a schematic structural diagram of a variable gain joint controller based on a nonlinear interference observer for an abrasive water jet polishing system based on multi-axis drive control according to an embodiment of the present invention.

In all drawings, the same reference numerals represent the same technical features, specifically: 1-sanding vehicle, 11-operation console, 12-lighting lamp, 13-rotating warning light, 14-overhead air conditioner, 15-driver Seat, 16-boarding ladder, 2-rail surface damage and profile front and rear detection system, 21-car body front end detection device, 22-car body rear end detection device, 3-grinding servo drive system, 31-bogie Components, 32-electrical cabinet, 33-drive traction transmission system, 34-cooling system, 35-air compressor, 4-ultra-high pressure water treatment system, 41-water tank, 42-boost pump, 5-water jet grinding system, 51-Grinding lifting mechanism, 52-Grinding actuator, 53-Abrasive supply mechanism, 531-Coarse abrasive tank, 532-Fine abrasive tank, 533-Coarse abrasive transmission channel, 534-Fine abrasive transmission channel, 535-Grinding water transmission channel , 54-first lifting unit, 541-vertical plate, 542-first fixed block, 543-second fixed block, 544-guide rod, 545-moving slider, 546-lift drive motor, 547-coupling, 548-ball screw, 55-the second lifting unit, 56-grinding actuator connecting bracket, 561-grinding lifting mechanism connecting piece, 562-grinding actuator connecting piece, 6-multi-channel grinding pressure flow control system, 61 -Pilot relief valve, 62-two-position two-way electromagnetic reversing valve, 63-remote pressure regulating valve, 64-ultra-high pressure water jet, 57-grinding execution unit, 571-first rotating motor, 572-second rotation Motor, 573-third rotating motor, 574-grinding water jet, 7-waste water recovery and separation system.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

In the description of the present invention, it should be noted that, unless expressly stated otherwise, when an element is referred to as being "fixed to", "disposed on" or "provided to" another element, it can be directly on the other element. element or indirectly on another element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element; the terms "mounted," "connected," "connected," "provided with" "should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, or it can be an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediary, it can be It is the internal connection between two elements or the interaction between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Furthermore, the terms "first", "second"... are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Thus, features defined as "first", "second"... may explicitly or implicitly include one or more of these features. In the description of the present invention, "plurality" means two or more than two, unless otherwise explicitly and specifically limited.

As shown in Figures 1 to 6, the present invention provides an abrasive water jet grinding system based on multi-axis drive control, including a grinding car 1, a vehicle control system installed on the grinding car 1, and a rail surface damage and profile front and rear detection system 2, grinding servo drive system 3, ultra-high pressure water treatment system 4, water jet grinding system 5, multi-channel grinding pressure flow control system 6 and wastewater recovery and separation system 7; the rail surface damage and contour The front and rear shape detection system 2 is used to measure the rails in real time before and after polishing, including assessing the rail condition before polishing, intelligently generating a polishing plan, judging the polishing quality after polishing, and optimizing the polishing plan; the polishing The servo drive system 3 is used to control the water jet with high precision to perform profile and high-precision grinding of the rails; the ultra-high-pressure water treatment system 4 is used to generate ultra-high-pressure water jets; the water jet grinding system 5 is configured The rails are restoratively polished at the bottom of the grinding vehicle frame; the multi-channel grinding pressure flow control system 6 can accurately control the pressure and flow of the water jet in each channel, thereby improving the grinding accuracy; the waste water recovery and separation system 7 is used to recycle grinding wastewater and separate water from abrasives to achieve recycling of water resources. By designing a vehicle-mounted intelligent abrasive water jet polishing system, the present invention arranges multiple water jet cutting heads along the longitudinal direction of the rail (traveling direction) and distributes them transversely along the rail at different angles. The grinding angle of the grinding head and the water jet grinding pressure Precise and controllable, it can realize multi-angle and high-precision grinding of rails. A high-precision, multi-degree-of-freedom posture control system is designed on each group of water jets to achieve high-precision rail profile grinding, and a high-precision water jet pressure control system is designed in each group of water jet channels to achieve water jet pressure and flow. And precise control of grinding quantity quality and flow rate. It can solve the defects of the existing grinding wheel that easily burns the rails, causing continuous blue bands, environmental pollution during the grinding process, and large fire hazards, as well as the uncontrollable grinding accuracy of the existing ultra-high-pressure abrasive water jet grinding rails and the water jet recoil affecting the stability of the water jet. properties, which directly affects the grinding accuracy.

Further, as shown in Figures 1 to 6, the rail surface damage and profile front and rear detection system 2 includes a vehicle body front end detection device 21 installed at the front end of the grinding vehicle 1 and a vehicle body front end detection device 21 installed at the rear of the grinding vehicle 1 The car body rear end detection device 22 at the end; the car body front end detection device 21 and the car body rear end detection device 22 are integrated with a 3D structured light detection system for detecting rail profile and surface defects, respectively. It is used to inspect the rail condition before grinding by the grinding machine, remove foreign matter and evaluate the rail surface quality after grinding by the grinding machine. The invention intelligently generates a grinding plan by evaluating rail conditions before grinding, judges the grinding quality after grinding, and optimizes the grinding plan.

Further, as shown in Figures 1-6, the grinding servo drive system 3 includes a bogie assembly 31, an electrical cabinet 32, a driving and traction transmission system 33, a cooling system 34 and an air compressor provided on the grinding car 1 Machine 35; the bogie assembly 31 includes a first bogie 311 and a second bogie 312 spaced apart along the longitudinal axis of the track to be polished. The first bogie 311 and the second bogie 312 are both two-axis powered. Bogie; the electrical cabinet 32 is located in the front driver's cab of the grinding vehicle, and the hardware equipment required for the control of the grinding vehicle is installed in the electrical cabinet; the driving traction transmission system 33 includes a diesel engine, a generator set, and a hydraulic transmission box, which is used for The entire grinding vehicle provides power and electricity; the cooling system 34 is driven by a hydraulic station and is responsible for the cooling of the diesel engine and the cooling of hydraulic transmission oil and other components in the hydraulic transmission box; the air compressor 35 is used to provide power for the grinding vehicle 1 The air brake provides power and at the same time provides power for abrasive transmission for the water jet grinding vehicle; the ultra-high pressure water treatment system 4 includes a water tank 41 and a booster pump 42 provided on the grinding vehicle 1; the water tank 41 is used for Store water source; the booster pump 42 is used to boost the water in the water tank. After the booster pump, the water pressure can reach a maximum of 420Mpa or more, which is used for water jet polishing.

Further, as shown in Figures 1-6, the water jet polishing system 5 includes a polishing lifting mechanism 51, a polishing actuator 52 provided on the polishing lifting mechanism 51, and an abrasive connected to the polishing actuator 52. Supply mechanism 53; the grinding lifting mechanism 51 is installed inside the compartment of the grinding car 1, and the grinding actuator 52 can be lifted into the grinding car compartment through the grinding lifting mechanism 51; in order to ensure that the grinding actuator The grinding height of 52 is accurately controllable. The grinding lifting mechanism 51 is designed as a bilateral trapezoidal screw sliding mechanism to achieve high control of the grinding mechanism and to achieve position self-locking. It includes first lifting units 54 arranged in parallel and opposite directions and spaced apart. The second lifting unit 55; the structures of the first lifting unit 54 and the second lifting unit 55 are exactly the same, and a grinding actuator connection bracket is provided between the first lifting unit 54 and the second lifting unit 55. 56; The lifting movement of the grinding actuator connecting bracket 56 is realized through the synchronous lifting of the first lifting unit 54 and the second lifting unit 55; the grinding actuator connecting bracket 56 is used to install the grinding actuator. 52; includes a grinding lifting mechanism connecting piece 561 and a grinding actuator connecting piece 562; the grinding lifting mechanism connecting piece 561 is a U-shaped structure with an opening downward; the grinding actuator connecting piece 562 is a rectangular plate-shaped structure; the The grinding actuator connector 562 is provided at the lower end of the U-shaped opening of the grinding lifting mechanism connector 561. The grinding actuator connector 562 and the grinding actuator connector 562 together form a rectangular frame structure; the grinding actuator A plurality of mounting holes are evenly spaced on the connecting piece 562 for installing a plurality of the grinding actuators 52; the grinding actuator is realized through the synchronous lifting of the first lifting unit 54 and the second lifting unit 55. 52 moves up and down evenly to ensure that the grinding height of the grinding actuator 52 is precise and controllable.

Further, as shown in FIGS. 1 to 6 , the first lifting unit 54 and the second lifting unit 55 each include a vertical plate 541 , and first lifting elements arranged in parallel and spaced apart from top to bottom on the vertical plate 541 . The fixed block 542 and the second fixed block 543, the guide rod 544 vertically spaced between the first fixed block 542 and the second fixed block 543, and the moving slide block provided on the guide rod 544 545. The lift drive motor 546 provided on the top side of the vertical plate 541, the coupling 547 provided on the output end of the lift drive motor 546, and the ball screw 548 provided on the output end of the coupling 547; The drive motor 546 and the coupling 547 are arranged above the first fixed block 542 in sequence from top to bottom, and the ball screw 548 passes through the first fixed block 542 and the moving slide block 545 in sequence. And installed on the second fixed block 543; the ball screw 548 and the guide rod 544 are arranged vertically and parallel to each other; the moving slider 545 is fixedly connected to the nut of the ball screw 548 through the nut. The up and down spiral movement drives the up and down lifting movement of the moving slide block 545; both sides of the grinding lifting mechanism connecting piece 561 are respectively connected with the moving slide blocks 545 on the first lifting unit 54 and the second lifting unit 55. Fixed connection, through the start of the lifting drive motors on the first lifting unit 54 and the second lifting unit 55, the coupling is driven to rotate, and then the rotation of the ball screw is converted into the up and down lifting of the moving slider. The movement, in turn, drives the up and down movement of the grinding actuator connecting bracket 56, and finally drives the up and down movement of the grinding actuator 52, thereby achieving precise control of the grinding height of the grinding actuator 52 and achieving self-locking position.

Further, as shown in Figures 1 to 8, each section of rail is provided with 2 sets of grinding actuators 52, with a total of 4 sets of rigid rails on both sides; the two sets of grinding actuators 52 on the same side are used to realize the grinding of the rails. The grinding actuator 52 includes a plurality of grinding execution units 57, and each grinding execution unit 57 includes three vertical axes: Z-axis, Y-axis, and X-axis. The first rotary motor 571, the second rotary motor 572, the third rotary motor 573, the grinding water jet 574 disposed at the output end of the third rotary motor 573, and the waste water disposed on the grinding water jet 574. The recovery unit 575 and the mounting plate 576 provided at the output end of the first rotating motor 571; the mounting plate 576 is used to fix the grinding execution unit 57 and the grinding actuator connection 562; each group of the grinding execution The mechanism 52 preferably includes four grinding execution units 57; that is, each group of the grinding execution units 52 is preferably provided with four grinding water jets 574, and the grinding execution unit 57 is provided with a Z-axis, a Y-axis, an 3-axis full servo drive mechanism. According to the preset polishing plan, each polishing water jet 574 can be rotated to the corresponding polishing position under the control of the X-axis, Y-axis, and Z-axis motors. After all polishing water jets 574 are linked, It can effectively fit the rail profile and complete the rigid rail repair work; the present invention arranges multiple grinding water jet cutting heads along the longitudinal direction of the rail (traveling direction) and distributes them transversely along the rail at different angles. The angle and water jet grinding pressure are accurately controllable, enabling multi-angle, high-precision grinding of rails.

Further, as shown in Figures 1 to 8, through the control linkage between the grinding lifting mechanism 51 and the X, Y, Z 3-axis full servo drive mechanism provided on the grinding execution unit 57, the position and posture of the high-pressure water jet water jet is driven. Control; During the grinding process, due to the elasticity of the drive motor of the 3-axis full servo drive mechanism and the mechanical transmission structure connected to it, during the grinding process, the grinding force will cause buffeting at the end of the grinding water jet, affecting the grinding effect; this The invention adopts a decentralized control strategy based on joint space to control single joints separately; decentralized control has the advantages of simple structure and fast calculation compared to task space-based control, and the system is highly robust to uncertainty; therefore, in order to improve the drive system Anti-interference and robustness, the controller that controls the full servo drive mechanism of the first rotating motor 571, the second rotating motor 572, and the third rotating motor 573 adopts a variable gain joint controller with a nonlinear disturbance observer, Through the decentralized control strategy based on joint space, single joints are controlled separately; based on the basic idea of the interference observer, a nonlinear interference observer (NDO) is used to estimate the unknown external disturbance of the abrasive water jet polishing system of the present invention, and the estimated The measured results are used as system output compensation. On this basis, the joint controller is designed in combination with the variable gain sliding mode control algorithm to ensure the tracking accuracy and stability of the joint servo system, thereby achieving stable tracking of the polishing waterjet posture; the present invention The controller design of the variable gain joint system based on the nonlinear disturbance observer includes the following steps:

Design the switching function of the variable gain joint controller according to the following formula:

In the formula,

is the derivation function of the switching function S; k(S) is an intermediate function and has no practical significance; α, β, k, η, and δ are variable gain joint system constants based on the nonlinear interference observer, 0＜α＜1, β>0, k>0, eta>0, 0<δ<1;

In the variable gain reaching law shown in the above formula, when the system operating trajectory is far away from the switching surface, that is, when the switching function modulus value |S| is relatively large, there is

It shows that the system can quickly approach the switching surface; when the system running trajectory is relatively close to the switching surface, there is

It shows that the system can effectively suppress chattering;;

The variable gain joint controller of the present invention is a multi-axis n-order single-input single-output nonlinear system, and its control law is as follows:

In the formula, x ₁ is the actual output position, x ₂ is the actual speed, x ₃ is the actual acceleration, x _n is the n-1 order derivative of the position, which generally does not represent a clear meaning, but is just to express the system state, X = [x ₁ ^x _{2 …} Uncertainty equivalent disturbances such as internal parameter perturbations and external disturbances of the output nonlinear system are bounded, that is, |d(t)|≤D≤+∞, and D is a constant;

Desired position for a given input,

are the desired position, velocity, and acceleration respectively. Let the tracking error of the multi-axis n-order single-input single-output nonlinear system be:

E=X _d -X (3),

In the formula, E=[e ₁ e ₂ ... e _n ] ^T .

The switching function S can be expressed as:

S＝C·E＝c ₁ e ₁ +c ₂ e ₂ +…+e _n (4),

In the formula, C = [c ₁ c ₂ … c _n-1 1], where c ₁ , c ₂ … c _n-1 are constants;

Then there is the derivation function of the switching function S:

From the above formula, the control law of the multi-axis n-order single-input single-output nonlinear system is

c is a constant, e _i is the tracking error, combined with the design method of the nonlinear interference observer, the observer is designed according to the following formula:

In the formula,

is the estimation error value of the nonlinear interference observer, z _f is the intermediate calculation function; p (x ₃ ) is the nonlinear function of the observer, L>0 is the coefficient of the nonlinear interference observer, satisfying

The observation error of the nonlinear interference observer is defined as:

Based on the analysis of interference error convergence, the estimated error value

After passing through the gain adjustment module, it is converted into the control input u _g at the input end. Taking the gain size as g, we have

It can be seen from the above that when a suitable g value is given, the observer can well compensate for the total uncertainty disturbance of the system; here, it is assumed that

At this time there is

After adopting the nonlinear interference observer, the total uncertainty interference of the system is greatly reduced, from G to

Then the system state equation can be transformed into

Then the system output after compensation through the nonlinear interference observer is:

In the formula, Sgn is a universal symbolic function in mathematics.

Further, as shown in Figures 1-6, the abrasive supply mechanism 53 includes a coarse abrasive tank 531 and a fine abrasive tank 532 provided on the air compressor 35. The coarse abrasive tank 531 stores larger abrasives. It is connected to the grinding actuator 52 through a coarse abrasive transmission channel 533, and is used to realize rough grinding of the rail; the fine abrasive tank 532 stores smaller abrasives, and is connected to the grinding actuator 52 through a fine abrasive transmission channel 534, It is used to achieve fine grinding of the rail; the booster pump 42 and the grinding actuator 52 are connected through a grinding water transmission channel 535, and the water in the water tank 41 is pressurized by the booster pump 42 to form a Ultra-high pressure water is supplied to the grinding actuator 52 through the grinding water transmission channel 535, and the water jet grinding pressure and flow rate are accurately controlled through the multi-channel grinding pressure flow control system 6.

Further, as shown in Figures 1-6, the multi-channel grinding pressure flow control system 6 is set up in each water jet channel, and includes an ultra-high-pressure water jet 61 pressurized by a booster pump, and a grinding machine. The pilot relief valve 62 connected to the hydraulic channel of the upper hydraulic pump, the electromagnetic reversing valve 63 provided at the remote control port of the pilot relieving valve 62 and the third electromagnetic reversing valve 63 can be connected respectively. A remote pressure regulating valve 64 and a second remote pressure regulating valve 65; the electromagnetic reversing valve 63 is a two-position two-way solenoid valve; the pilot relief valve 62, the first remote pressure regulating valve 64 and all The second remote pressure regulating valve 65 can adjust the hydraulic pump outlet pressure; when the electromagnetic reversing valve 63 is powered off and in the neutral position, the working pressure of the water jet is set to the highest pressure by the pilot relief valve 62 ; When the left electromagnet of the electromagnetic reversing valve 63 is energized to the left position, the working pressure of the hydraulic pump is set to a lower pressure by the first remote pressure regulating valve 64 (relief valve); when the right electromagnet of the electromagnetic reversing valve 41 is energized. When the power is in the right position, the working pressure of the hydraulic pump is set to a lower pressure by the second remote pressure regulating valve 65 (relief valve) (the pressure everywhere is generally different from the lower pressure set by the first remote pressure regulating valve 64); The invention uses a pilot relief valve, an electromagnetic reversing valve and a remote pressure regulating valve to realize multi-stage pressure regulation or remote pressure regulation of the water jet channel.

Further, as shown in Figure 1, the polishing vehicle 1 is also equipped with an operating console 11, a lighting lamp 12, a rotating warning light 13, an overhead air conditioner 14, a driver's seat 15 and a boarding ladder 16; the operating console 11 is equipped with In the front part of the front driver's cab, the observation position is equipped with a wind meter, vehicle parameter display screen, indicator lights, etc.; the operating position is equipped with a driver controller, lighting-related switches, air pipeline-related switches, and other electronic control component switches. These components detect and control the operating status of the vehicle in real time; the lighting lamp 12 is located at the front end of the driver's cab in front of the vehicle body; the rotating warning light 13 is installed at the front and rear ends of the top of the vehicle body, and is generally lit during use of the vehicle; the overhead air conditioner 14 It is installed on the top of the front driver's cab and the top of the machine room respectively. It uses a special roof unit air conditioner for heating and cooling. It is an all-in-one machine with a thin design, small size and light weight. The driver's seat 15 is located in the front driver's cab and is divided into observation positions. , 2 seats at the operating position; the boarding ladder 16 is used for the driver and related staff to get up and down the car.

The working principle of an abrasive water jet polishing system based on multi-axis drive control provided by the present invention: by designing a vehicle-mounted intelligent abrasive water jet polishing system, multiple polishing water jet cutting heads are arranged along the longitudinal direction of the rail (traveling direction). It is distributed laterally along the rail at different angles. The grinding angle of the grinding head and the water jet grinding pressure are accurately controllable, which can realize multi-angle and high-precision grinding of the rail. A high-precision, multi-degree-of-freedom posture control system is designed on each group of water jets to achieve high-precision rail profile grinding, and a high-precision water jet pressure control system is designed in each group of water jet channels to achieve water jet pressure and flow. And precise control of grinding quantity quality and flow rate. It can solve the defects of the existing grinding wheel that easily burns the rails, causing continuous blue bands, environmental pollution during the grinding process, and large fire hazards, as well as the uncontrollable grinding accuracy of the existing ultra-high-pressure abrasive water jet grinding rails and the water jet recoil affecting the stability of the water jet. properties, which directly affects the grinding accuracy.

It is easy for those skilled in the art to understand that the above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements, etc., made within the spirit and principles of the present invention, All should be included in the protection scope of the present invention.

Claims (10)

1. An abrasive water jet grinding system based on multi-axis drive control, characterized by: including a grinding car (1), a vehicle control system installed on the grinding car (1), rail surface damage and profile front and rear detection System (2), grinding servo drive system (3), ultra-high pressure water treatment system (4), water jet grinding system (5), multi-channel grinding pressure flow control system (6) and wastewater recovery and separation system (7); among which ,

   The water jet grinding system (5) includes a grinding lifting mechanism (51), a grinding actuator (52) provided on the grinding lifting mechanism (51), and an abrasive supply mechanism connected to the grinding actuator (52). (53); The grinding lifting mechanism (51) is a bilateral trapezoidal screw sliding mechanism, which can realize the height control of the grinding actuator (52) and realize position self-locking; each rail section is provided with at least 2 sets of the grinding actuators Mechanism (52), the grinding actuator (52) on the same side is respectively used to realize rough grinding and then fine grinding of the rail; the grinding actuator (52) includes multiple grinding execution units (57), which combine multiple grinding execution units (57). The grinding execution units (57) are arranged along the traveling direction of the rail, and are distributed transversely along the rail at different angles. A 3-axis full servo drive mechanism is provided on each grinding execution unit (57), so that each grinding execution unit (57) is The grinding angle of the execution unit (57) is controllable; the grinding servo drive system (3) controls the high-precision position and posture linkage of multiple grinding execution units (57) and fits the rail profile to achieve the purpose of repairing the rail. Profile high-precision grinding; and a high-precision multi-channel grinding pressure flow control system (6) is designed in the grinding execution unit (57) channel to achieve precise control of water jet pressure and flow.
2. An abrasive water jet polishing system based on multi-axis drive control according to claim 1, characterized in that: the multi-channel polishing pressure flow control system (6) can accurately control the pressure and flow rate of each channel water jet. control, thereby improving grinding accuracy;

   The multi-channel grinding pressure flow control system (6) includes an ultra-high-pressure water jet (61) pressurized by a booster pump, a pilot relief valve (62) connected to the hydraulic channel of the hydraulic pump on the grinding vehicle, and a The electromagnetic reversing valve (63) at the remote control port of the pilot relief valve (62) and the first remote pressure regulating valve (64) and the third remote pressure regulating valve (64) respectively connected through the electromagnetic reversing valve (63). Two remote pressure regulating valves (65);

   The electromagnetic reversing valve (63) is a two-position, two-way solenoid valve;

   The pilot relief valve (62), the first remote pressure regulating valve (64) and the second remote pressure regulating valve (65) can all adjust the hydraulic pump outlet pressure.
3. An abrasive water jet polishing system based on multi-axis drive control according to claim 2, characterized in that: the polishing lifting mechanism (51) includes a first lifting unit (54) and a second lifting unit (54) arranged in parallel and spaced oppositely. unit (55) and a grinding actuator connecting bracket (56) provided between the first lifting unit (54) and the second lifting unit (55); the grinding actuator (52) is installed on the The grinding actuator is connected to the bracket (56); through the synchronous lifting of the first lifting unit (54) and the second lifting unit (55), the lifting movement of the grinding actuator connecting bracket (56) is realized, thereby driving The grinding actuator (52) moves up and down.
4. An abrasive water jet grinding system based on multi-axis drive control according to claim 3, characterized in that: the grinding actuator connecting bracket (56) includes a grinding lifting mechanism connecting piece (561) and a grinding actuator connecting piece (562);

   The grinding actuator connector (562) is located at the lower end of the grinding lifting mechanism connector (561), and the grinding actuator connector (562) and the grinding actuator connector (562) together form a rectangular frame structure;

   The grinding actuator connecting piece (562) is evenly spaced with a plurality of mounting holes for installing the grinding actuator (52).
5. An abrasive water jet polishing system based on multi-axis drive control according to claim 4, characterized in that: the structures of the first lifting unit (54) and the second lifting unit (55) are exactly the same;

   The first lifting unit (54) and the second lifting unit (55) each include a vertical plate (541), and first fixed blocks (542) spaced parallelly from top to bottom on the vertical plate (541). ) and the second fixed block (543), a guide rod (544) vertically spaced in parallel between the first fixed block (542) and the second fixed block (543), and a guide rod (544) provided on the guide rod. (544) on the moving slider (545), the lifting drive motor (546) provided on the top side of the vertical plate (541), the coupling (547) provided on the output end of the lifting drive motor (546), and The ball screw (548) provided at the output end of the coupling (547);

   The lifting drive motor (546) and the coupling (547) are arranged above the first fixed block (542) in order from top to bottom;

   The ball screw (548) passes through the first fixed block (542) and the moving slider (545) in sequence and is installed on the second fixed block (543);

   The ball screw (548) and the guide rod (544) are arranged vertically and parallel to each other;

   The moving slide block (545) is fixedly connected to the nut of the ball screw (548), and the upward and downward spiral movement of the nut drives the up and down lifting movement of the moving slide block (545).
6. An abrasive water jet polishing system based on multi-axis drive control according to claim 5, characterized in that: both sides of the polishing lifting mechanism connecting piece (561) are respectively connected with the first lifting unit (54) and The moving slider (545) on the second lifting unit (55) is fixedly connected, and is started by the lifting drive motors on the first lifting unit (54) and the second lifting unit (55) to drive the coupling. The rotation of the ball screw (548) drives the rotation of the ball screw (548) into the up and down lifting motion of the moving slider (545), which then drives the up and down movement of the connecting bracket (56) of the grinding actuator, and finally drives the grinding actuator. The up and down movement of the actuator (52) realizes precise control of the grinding height.
7. An abrasive water jet grinding system based on multi-axis drive control according to any one of claims 1-6, characterized in that: the grinding actuator (52) includes a plurality of grinding execution units (57), each The grinding execution unit (57) includes a first rotary motor (571), a second rotary motor (572), a third rotary motor (573) arranged perpendicularly to each other from top to bottom. The grinding water jet (574) at the output end of the three rotating motors (573), the waste water recovery unit (575) provided on the grinding water jet (574), and the mounting plate (575) provided at the output end of the first rotating motor (571) 576);

   The mounting plate (576) is used to fix the grinding execution unit (57) and the grinding actuator connection piece (562).
8. An abrasive water jet polishing system based on multi-axis drive control according to claim 7, characterized in that: controlling the first rotating motor (571), the second rotating motor (572), the third rotating motor (573) )'s full servo drive mechanism uses a variable-gain joint controller with a nonlinear interference observer. Through a decentralized control strategy based on joint space, single joints are controlled separately; a nonlinear interference observer is used to estimate abrasive water jet polishing. Unknown external disturbances to the system, and the estimated results are used as system output compensation. On this basis, the joint controller is designed in conjunction with the variable gain sliding mode control algorithm to ensure the tracking accuracy and stability of the joint servo system, thereby achieving polishing water Stable tracking of knife posture;

   Design the switching function of the variable gain joint controller according to the following formula:

   

   In the formula,

   

   is the derivation function of the switching function S; k(S) is an intermediate function and has no practical significance; α, β, k, η, and δ are variable gain joint system constants based on the nonlinear interference observer, 0＜α＜1, β>0, k>0, eta>0, 0<δ<1;

   In the variable gain reaching law shown in the above formula, when the system operating trajectory is far away from the switching surface, that is, when the switching function modulus value |S| is relatively large, there is

   

   It shows that the system can quickly approach the switching surface; when the system running trajectory is relatively close to the switching surface, there is

   

   It shows that the system can effectively suppress chattering;

   The variable gain joint controller is a multi-axis n-order single-input single-output nonlinear system, and its control law is as follows:

   

   In the formula, x ₁ is the actual output position, x ₂ is the actual speed, x ₃ is the actual acceleration, x _n is the n-1 order derivative of the position, which generally does not represent a clear meaning, but is just to express the system state, X = [x ₁ ^x _{2 …} Uncertainty equivalent disturbances such as internal parameter perturbations and external disturbances of the output nonlinear system are bounded, that is, |d(t)|≤D≤+∞, and D is a constant;

   

   Desired position for a given input,

   

   are the desired position, velocity, and acceleration respectively. Let the tracking error of the multi-axis n-order single-input single-output nonlinear system be:

   E＝ _Xd -X，

   In the formula, E=[e ₁ e ₂ … e _n ] ^T ;

   The switching function S can be expressed as:

   S＝C·E＝c ₁ e ₁ +c ₂ e ₂ +…+e _n

   In the formula, C = [c ₁ c ₂ … c _n-1 1], where c ₁ , c ₂ … c _n-1 are constants;

   Then there is the derivation function of the switching function S:

   

   From the above formula, the control law of the multi-axis n-order single-input single-output nonlinear system is

   

   c is a constant, e _i is the tracking error, combined with the design method of the nonlinear interference observer, the observer is designed according to the following formula:

   

   In the formula,

   

   is the estimation error value of the nonlinear interference observer, z _f is the intermediate calculation function; p (x ₃ ) is the nonlinear function of the observer, L>0 is the coefficient of the nonlinear interference observer, satisfying

   

   The observation error of the nonlinear interference observer is defined as:

   

   Based on the analysis of interference error convergence, the estimated error value

   

   After passing through the gain adjustment module, it is converted into the control input u _g at the input end. Taking the gain size as g, we have

   

   When a suitable g value is given, the observer can well compensate for the total uncertainty perturbation of the system; here, it is assumed that

   

   At this time there is

   

   After adopting the nonlinear interference observer, the total uncertainty interference of the system is greatly reduced, from G to

   

   Then the system state equation can be transformed into

   

   Then the system output after compensation through the nonlinear interference observer is:

   

   In the formula, Sgn is a universal symbolic function in mathematics.
9. An abrasive water jet polishing system based on multi-axis drive control according to any one of claims 1-6, characterized in that: the rail surface damage and profile front and rear detection system (2) includes The vehicle body front end detection device (21) at the front end of the grinding vehicle (1) and the vehicle body rear end detection device (22) installed at the rear end of the polishing vehicle (1); the vehicle body front end detection device (21) and the vehicle body rear end detection device (21) The above-mentioned vehicle body rear-end detection device (22) is integrated with a 3D structured light detection system for detecting rail profile and surface defects;

   The ultra-high pressure water treatment system (4) includes a water tank (41) and a booster pump (42) installed on the grinding vehicle (1); the water jet grinding system (5) is installed at the bottom of the grinding vehicle frame. ;

   The wastewater recycling and separation system (7) is used to recycle grinding wastewater and separate the water from the abrasive to realize recycling of water resources.
10. An abrasive water jet grinding system based on multi-axis drive control according to claim 9, characterized in that: the grinding servo drive system (3) includes a bogie assembly (1) provided on the grinding vehicle (1) 31), electrical cabinet (32), drive and traction transmission system (33), cooling system (34) and air compressor (35); the air compressor (35) is used to provide the air brake for the grinding vehicle (1) Provide power and at the same time provide power for abrasive transmission for the water jet grinding vehicle;

    The abrasive supply mechanism (53) includes a coarse abrasive tank (531) and a fine abrasive tank (532) provided on the air compressor (35). The coarse abrasive tank (531) is connected with the grinding actuator (531). 52) is connected through a coarse abrasive transmission channel (533) for rough grinding of the rail; the fine abrasive tank (532) is connected to the grinding actuator (52) through a fine abrasive transmission channel (534) for Achieve fine grinding of rails;

    The booster pump (42) and the polishing actuator (52) are connected through a polishing water transmission channel (535), and the water in the water tank (41) is pressurized by the booster pump (42). Ultra-high pressure water is formed and supplied to the grinding actuator (52) through the grinding water transmission channel (535), and the water jet grinding pressure and flow rate are accurately controlled through the multi-channel grinding pressure flow control system (6).

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