Anti-electromagnetic interference design method for wheel-foot humanoid robot in industrial scene

Abstract

The invention discloses an anti-electromagnetic interference design method for a wheel-foot humanoid robot in an industrial scene, and particularly relates to the technical field of robots, comprising: S1, constructing a dynamic following electromagnetic shielding structure; s2, establishing a hybrid drive isomeric map filtering system; s3, implementing cross-level electromagnetic compatibility collaborative design; and S4, whole machine cable wiring and grounding system optimization are carried out, layered bundling and directional wiring strategies are adopted, a hybrid grounding model is applied, a low-frequency circuit is in single-point grounding, a high-frequency circuit is in multi-point grounding, and subsystems are connected to a central grounding point through a low-impedance grounding bus. The electromagnetic leakage is avoided, the overall electromagnetic compatibility of the system is enhanced, and the common-mode interference and the ground loop influence are reduced, so that the control precision and the operation stability are ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of robots, and more particularly, to a wheel-foot humanoid robot anti-electromagnetic interference design method in an industrial scenario. BACKGROUND

[0002] With the rapid development of industrial intelligence, wheel-foot humanoid robots gradually find application in complex industrial environments due to their combination of the efficiency of wheeled movement and the adaptability of foot movement. However, strong electromagnetic interference in industrial environments and electromagnetic noise generated by the robot's own multi-joint motors and high-frequency control circuits seriously affect the robot's sensing accuracy and control stability. However, in the prior art, such robots have significant defects and problems in terms of anti-electromagnetic interference. First, at the rotary joint, the encoder magnetic ring lacks effective dynamic shielding measures, resulting in incomplete electromagnetic shielding during joint movement and susceptibility to external electromagnetic field interference, thereby affecting positioning accuracy and motion control stability. Second, the wheeled drive system and the foot joint drive system usually use a unified power supply and filtering scheme, ignoring the differences in noise spectrum characteristics between the two, causing low-frequency conducted interference and medium-high frequency switching noise to cross-couple between subsystems, reducing system reliability. In addition, existing designs often lack system-level electromagnetic compatibility coordination and only perform local optimization at a single level, such as the component level, without considering electromagnetic compatibility from the component, subsystem, to the whole machine level, resulting in local interference easily spreading to the entire system.

[0003] Therefore, in view of the above problems, an industrial scenario wheel-foot humanoid robot anti-electromagnetic interference design method is proposed. SUMMARY

[0004] In order to overcome the above-mentioned defects of the prior art, the present application provides an industrial scenario wheel-foot humanoid robot anti-electromagnetic interference design method to solve the problems raised in the background art.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solution: an industrial scenario wheel-foot humanoid robot anti-electromagnetic interference design method, comprising the following steps: S1, a dynamic following electromagnetic shielding structure is constructed, the dynamic following electromagnetic shielding structure is configured as a stepped shielding cover provided for an encoder magnetic ring in a robot rotary joint, and a Faraday cage is formed through the stepped shielding cover; S2, a hybrid drive heterogeneous graph filtering system is established, and independent power supply and filtering design is performed on the wheeled drive system and the foot joint drive system of the robot; S3, cross-level electromagnetic compatibility coordination design is implemented, and a three-level electromagnetic compatibility model is established for electromagnetic compatibility coordination design at the component level, subsystem level, and whole machine level of the robot; S4, the whole machine cable wiring and grounding system optimization: the robot internal wiring strategy adopts hierarchical bundling and directional wiring, the robot internal also has a hybrid grounding model, the hybrid grounding model includes a low-frequency circuit and a high-frequency circuit, the low-frequency circuit adopts single-point grounding, the high-frequency circuit adopts multi-point grounding, and the subsystems of the robot are connected to the central grounding point through a low-impedance grounding bus.

[0006] Preferably, in step S1, the Faraday cage keeps dynamic integrity with the movement of the rotary joint, and the Faraday cage is configured such that one side of the stepped shielding cover is connected with the encoder, the other side of the stepped shielding cover is connected with the shell of the rotary joint through elastic contacts, and the stepped shielding cover rotates synchronously with the encoder.

[0007] Preferably, in step S2, the power line of the wheeled drive system is configured as a large-current common-mode choke and a differential-mode π-type filter for suppressing low-frequency conducted interference, and the power line of the foot joint drive system is configured as a three-section capacitor filter and a ferrite magnet for suppressing medium and high frequency switching noise.

[0008] Preferably, in step S3, the electromagnetic compatibility collaborative design specifically includes: At the component level, the force sensor and communication module of the robot are locally shielded; At the subsystem level, the printed circuit board layout of the robot is optimized to partition high-frequency digital circuits and analog circuits and adopt independent grounding strategies; At the whole machine level, the overall shielding layer of the robot adopts a metal shell, and the gaps and cable openings of the metal shell are treated using electromagnetic sealing gaskets.

[0009] Preferably, in step S1, the stepped shielding cover adopts permalloy, the dynamic following electromagnetic shielding structure includes an inner layer of conductive gasket and an outer layer of magnetic shielding layer, the inner layer of conductive gasket adopts a composite structure of metal woven mesh and conductive rubber, so that the stepped shielding cover makes low-impedance contact with the shell of the rotary joint.

[0010] Preferably, in step S2, the heterogeneous graph filtering system is characterized in that filters with different frequency attenuation characteristics are used according to the different noise spectrum characteristics of the wheel drive system and the joint drive system, so as to avoid noise cross-coupling between the subsystems.

[0011] Preferably, in step S3, the three-level electromagnetic compatibility model further includes: analyzing the influence of the transient electromagnetic environment on the system through front-door coupling and back-door coupling by establishing a system model, and calculating and distributing the sensitivity threshold indicators of the components inside the robot accordingly.

[0012] Preferably, in step S1, the cylindrical shell of the dynamic following electromagnetic shielding structure is provided with at least one fixed claw, which extends radially outward and then extends axially away from the stepped shielding cover, so as to realize detachable connection with the shell of the rotary joint.

[0013] Preferably, in step S3, the cross-level electromagnetic compatibility collaborative design further includes a software anti-interference strategy based on a robust controller, a high-robustness controller for inhibiting system self-model uncertainty and external electromagnetic disturbance is constructed by establishing a state space expression of the joint control system and minimizing H∞ norm of a closed-loop transfer function of external interference to system generalized performance output.

[0014] Preferably, in step S3, the metal shell surface of the robot is coated with electromagnetic shielding paint, the electromagnetic shielding paint is composed of conductive fillers and polymer resins, and the electromagnetic shielding paint forms a continuous conductive coating.

[0015] The technical effects and advantages of the present application are as follows: 1. Compared with the prior art, the wheel-legged humanoid robot anti-electromagnetic interference design method in the industrial scene can effectively improve the anti-electromagnetic interference ability of the wheel-legged humanoid robot by integrating the dynamic following electromagnetic shielding structure, the mixed driving heterogeneous graph filtering system, the cross-level electromagnetic compatibility collaborative design, and the optimization of the whole machine cable wiring and grounding system.

[0016] 2. Compared with the prior art, the wheel-legged humanoid robot anti-electromagnetic interference design method in the industrial scene forms a dynamic complete Faraday cage through the stepped shielding cover, ensures the shielding continuity of the encoder magnetic ring during the movement of the rotary joint, and thus avoids electromagnetic leakage caused by joint movement.

[0017] 3. Compared with the prior art, the wheel-legged humanoid robot anti-electromagnetic interference design method in the industrial scene adopts a heterogeneous graph filtering strategy to suppress low-frequency and medium-high frequency noise respectively and prevent noise cross-coupling through independent power supply and filtering design for the wheeled and foot-type driving systems.

[0018] 4. Compared with the prior art, the wheel-legged humanoid robot anti-electromagnetic interference design method in the industrial scene realizes the organic combination of local shielding, circuit partitioning and overall metal shell shielding by establishing a three-level electromagnetic compatibility model and performing collaborative design at the element level, subsystem level and whole machine level, thereby enhancing the overall electromagnetic compatibility of the system.

[0019] 5. Compared with the prior art, the wheel-legged humanoid robot anti-electromagnetic interference design method in the industrial scene reduces the ground impedance of low-frequency and high-frequency circuits and reduces common-mode interference and ground loop effects by optimizing the cable wiring and grounding system and adopting layered bundling, directional wiring and mixed grounding model. BRIEF DESCRIPTION OF DRAWINGS

[0020] Fig. 1 A flow chart of the method of the present application.

[0021] Fig. 2 A schematic diagram of the electromagnetic compatibility synergy of the present application. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0023] Embodiment 1 As shown in the industrial scene of the wheel-foot humanoid robot anti-electromagnetic interference design method, comprising the following steps: Figs. 1-2 S1, constructing a dynamic following electromagnetic shielding structure, the dynamic following electromagnetic shielding structure is configured to set a stepped shielding cover for the encoder magnetic ring in the robot rotary joint, and a Faraday cage is formed through the stepped shielding cover; S2, establishing a hybrid driving heterogeneous graph filtering system, independently supplying power and filtering design for the wheeled driving system and the foot joint driving system of the robot; S3, implementing cross-level electromagnetic compatibility synergy design, establishing a three-level electromagnetic compatibility model for electromagnetic compatibility synergy design at the element level, subsystem level and whole machine level of the robot; S4, optimizing the whole machine cable wiring and grounding system: the internal wiring strategy of the robot adopts layered bundling and directional wiring, and the internal part of the robot also has a hybrid grounding model, the hybrid grounding model includes a low-frequency circuit and a high-frequency circuit, the low-frequency circuit adopts single-point grounding, the high-frequency circuit adopts multi-point grounding, and the subsystems of the robot are connected to the central grounding point through a low-impedance grounding bus. Specifically, the implementation starts from constructing a dynamic following electromagnetic shielding structure, the core of which is to install a customized stepped shielding cover for the precise encoder magnetic ring inside the rotary joint of the robot. The shielding cover is designed to have multiple concentric cylindrical stepped structures with varying diameters, which can tightly wrap the encoder magnetic ring and its lead wires. Its working principle is to completely surround the encoder magnetic ring with a shielding cover with good electrical conductivity according to the Faraday cage effect, thereby isolating the intrusion of external electromagnetic fields. In implementation, the stepped shielding cover is usually precisely stamped and formed with high magnetic permeability materials such as permalloy to ensure the formation of a continuous electromagnetic shielding body;

[0024] ​To achieve dynamic following, one side of the shield is firmly connected to the encoder body by interference fit or conductive adhesive, enabling it to rotate synchronously with the encoder core components; the other side is in sliding contact with the stationary housing of the rotary joint through gold-plated beryllium copper alloy elastic contacts. These elastic contacts are evenly distributed circumferentially, providing a stable low-impedance electrical connection at all times when the joint is rotating, so that no matter what angle the joint is at, the Faraday cage formed by the shield can maintain electrical continuity and integrity, effectively preventing the problem of electromagnetic shielding interruption caused by joint movement. In order to effectively implement the hybrid grounding model of high and low frequency circuits and avoid the risk of common ground impedance coupling, the key to optimizing the cable wiring and grounding system of the robot as a whole is to finely design and partition the ground plane of the printed circuit board. In implementation, first, strictly partition according to circuit signal frequency and characteristics, clearly separate low-frequency analog circuits, high-frequency digital circuits, and high-power drive circuits in physical layout, and divide each functional area into an independent grounding area. Complete ground planes are used within each partition to ensure low-impedance return paths, and a multi-point grounding strategy is implemented within the high-frequency circuit partition to make its return path the shortest. Between independent ground planes in different partitions, an isolation strip with a width of not less than 2mm is set to prevent the spread of ground noise. These isolated ground planes are not completely isolated, but are interconnected through a star-shaped connection structure called a "ground collection point". This ground collection point is usually a thick copper plate or a dedicated ground bus, and is set in a low-noise sensitive and centrally located area on the PCB. The ground planes of each partition are directly connected to this unique ground collection point in a radial manner through their own independent and as short and wide as possible leads, thus building a star-shaped grounding topology. This structure ensures that all ground currents eventually converge into a common point, effectively cutting off the coupling path formed by the common ground impedance. Finally, the collection point of the star-shaped ground is connected to the central grounding point of the robot through a low-impedance grounding bus. Through this implementation of partition isolation combined with star-shaped grounding, the different grounding needs of high and low frequency circuits are met, and noise coupling caused by common ground impedance is eliminated from the root, ensuring the actual effectiveness of the hybrid grounding model.

[0025] As a preferred embodiment, in step S1, the Faraday cage remains dynamically complete as the rotary joint moves, and the Faraday cage is configured such that one side of the stepped shield is connected to the encoder, the other side of the stepped shield is connected to the housing of the rotary joint through elastic contacts, and the stepped shield rotates synchronously with the encoder. To ensure the dynamic integrity of the Faraday cage formed by the stepped shield during the rotation of the joint. This principle is achieved through precise mechanical and electrical connection design. In implementation, the stepped shield is fixed to the encoder and rotates with it, while to form a closed electromagnetic shielding loop with the stationary joint shell, multiple circumferentially uniformly distributed micro-elastic contacts are integrated on the stepped platform of the shield opening edge. These contacts are usually made of beryllium copper alloy wire or sheet with excellent electrical conductivity and fatigue strength, with their roots welded or riveted to the shield edge and their free ends processed into smooth spherical or convex points. When assembled, these elastic contacts maintain constant sliding contact with the smooth conductive ring on the inner wall of the rotating joint shell under the action of pre-compression force. The surface of the conductive ring is often gold or silver plated to reduce contact resistance and prevent oxidation. This design ensures that regardless of the angle at which the encoder drives the shield to rotate, current can always pass through at least one set of elastic contacts to form a low-impedance path, ensuring that the electrical continuity of the Faraday cage is not disrupted by rotation, and achieving dynamic following of shielding effectiveness.

[0026] As a preferred embodiment, for the large current and low frequency characteristics of the wheeled drive system and the medium-high frequency switching noise characteristics of the foot joint drive system, filters with different frequency attenuation characteristics are used for independent filtering design. For the wheeled drive system, the power line filtering implementation is to install a large current common mode choke coil near the power input of the motor driver, which uses a high magnetic permeability ferrite core and is wound with multiple parallel enameled wires to withstand continuous tens of amperes of current. Its main function is to suppress low-frequency common-mode conducted interference by using its high common-mode impedance; then a differential-mode π-type filter is arranged after the choke coil, which is composed of two electrolytic capacitors and an intermediate inductor. The electrolytic capacitors provide bypass for differential-mode interference, while the inductor blocks the transmission of differential-mode noise, and the two work together to filter out low-frequency differential-mode interference on the power line. For the foot joint drive system, a three-section capacitor filter is first connected in parallel at the power inlet of the joint drive, which is composed of a large capacitance tantalum capacitor, a medium capacitance ceramic capacitor, and a small capacitance high-frequency ceramic capacitor connected in parallel, respectively responsible for filtering different frequency bands of switching noise, and providing a low-impedance return path for high-frequency current; On this basis, multiple nickel-zinc ferrite beads or rings are also installed in series on the power line, taking advantage of the characteristic that the impedance of ferrite material rises sharply at high frequencies, and designing the impedance characteristic curve of these high-frequency beads or rings to have the maximum impedance in the main frequency band of the switching noise, thereby effectively absorbing and attenuating the medium-high frequency switching noise on the line. Through this heterogeneous spectrum filtering design tailored to the frequency spectrum characteristics, the source of noise for the two types of drive systems is physically suppressed, effectively avoiding cross-coupling of noise between subsystems through the power network.

[0027] As a preferred embodiment, in step S3, the electromagnetic compatibility collaborative design specifically includes: At the component level, the force sensor and the communication module of the robot are locally shielded; At the subsystem level, the printed circuit board layout of the robot is optimized, so that the high-frequency digital circuit and the analog circuit are partitioned and an independent grounding strategy is adopted; At the whole machine level, the whole shielding layer of the robot adopts a metal shell, and the gaps and cable openings of the metal shell are treated using electromagnetic sealing gaskets.

[0028] Specifically, the key to the successful implementation of the three-level electromagnetic compatibility collaborative design is to ensure that the electromagnetic protection measures between the component level, the subsystem level and the whole machine level can seamlessly connect and match, thereby forming a complete defense system; The local shielding of the force sensor and the communication module at the component level is the basis for realizing the electromagnetic compatibility of the system; the specific implementation is to add an independent metal shield to these sensitive components, which is connected to the ground plane on the printed circuit board of the subsystem level through multiple ground pads with low impedance and multiple points. The positions of these ground pads need to be accurately planned to be as close as possible to the ground pins of the shielded components, so as to introduce the high-frequency return current generated by the component-level shielding layer into the subsystem ground plane, avoiding the introduction of additional inductance by long leads; This careful component-level shielding and grounding design directly reduces the difficulty of PCB layout optimization at the subsystem level, because the local noise has been effectively suppressed, so that when the high-frequency digital circuit and the analog circuit are partitioned at the subsystem level, the ground plane between them can be separated by a clearer isolation band, and independent grounding strategies are adopted, i.e., digital and analog grounds are connected only at one point through a zero-ohm resistor or a magnetic bead, which effectively prevents digital noise from interfering with the analog circuit through common ground coupling; Further, the electromagnetic radiation and conducted emission generated by the optimized subsystem itself are controlled, which lays the foundation for shielding at the whole machine level; at the whole machine level, the inner wall of the metal shell needs to maintain a reasonable spatial distance from each subsystem module that has been locally shielded and optimized in layout during assembly, and the shell ground lines of each subsystem, such as the overall ground of the PCB, must be connected to the designated ground column on the inner wall of the robot main metal shell through short and wide braided wires or metal supports, so as to ensure that the ground path impedance from the component to the subsystem to the whole machine shell is extremely low, forming a continuous and complete shielding system, and finally making the three-level electromagnetic compatibility measures work together to improve the anti-interference ability of the whole machine.

[0029] As a preferred embodiment, the shielding effectiveness and mechanical reliability are optimized by the use of composite materials and the design of layered shielding structure. In implementation, the main structure of the stepped shielding cover is manufactured by precise stamping and stepped deep drawing process using thin sheets of permalloy with extremely high magnetic permeability. This material can effectively guide and absorb stray magnetic field lines, providing excellent low-frequency magnetic shielding capability. To achieve low impedance contact, an inner conductive gasket is firmly bonded or molded on the end face of the shielding cover that needs to be in sliding contact with the rotating joint shell. The gasket is a composite structure of metal woven mesh and conductive rubber, where the fine silver-plated copper wire mesh provides high conductivity, and the filled silicone rubber-based conductive elastomer provides good compression resilience. In the assembled state, the composite gasket is moderately deformed under the pre-pressure of the elastic contact, ensuring a large area, low impedance electrical connection between the joint shell conductive ring and the gasket. To further enhance high-frequency shielding effect, an outer magnetic shielding layer is formed on the outer surface of the permalloy shielding cover by electroplating or spraying. This is usually a nickel-based or copper-based coating with high electrical conductivity, used to reflect high-frequency electromagnetic waves. This three-layer composite structure of inner conductive gasket, permalloy cover providing main magnetic shielding, and outer coating enhancing high-frequency shielding ensures that the stepped shielding cover always maintains a complete and efficient Faraday cage shielding effect under complex motion conditions of the robot joint.

[0030] As a preferred embodiment, in step S2, the heterogeneous spectrum filtering system is characterized by using filters with different frequency attenuation characteristics according to the different noise spectrum characteristics of the wheel drive system and the joint drive system, thereby avoiding noise cross-coupling between subsystems. According to the completely different noise spectrum characteristics of the wheel drive system and the joint drive system, filters with specific frequency attenuation characteristics are accurately configured for each subsystem, and the selection and parameter design of the filters are based on mathematical modeling of the noise source. The frequency selection characteristics of the heterogeneous spectrum filtering system can be represented by its transfer function , which can be generally expressed as:

[0031] , where represents the complex frequency variable jω; jω represents the angular frequency; and represent the Laplace transform of the input and output voltages of the filter, respectively; n represents the order of the denominator polynomial, which determines the order of the filter; , ... represent real coefficients determined by the specific parameter values of resistors, capacitors, inductors and other elements in the filter circuit. These coefficients together shape the amplitude-frequency response of the filter in the frequency domain |, i.e. the attenuation ability to different frequency noises; For the wheel driving system, the noise energy is mainly concentrated in the low frequency band, so the denominator order n of the transfer function needs to be designed to be low, but the coefficient The filter with optimized low cut-off frequency, for example, is selected as So that | After the filter with low cut-off frequency, it decreases with a slope of -20n dB per decade, so as to effectively suppress the low frequency conducted interference; and for the foot joint driving system, the switch noise is rich in high frequency harmonics, so a filter with higher order n and specific coefficient combination needs to be designed, so that the transfer function has poles near multiple high frequency points, so as to realize steep attenuation in a wide frequency band, for example, the design with n≥3 makes | Maintains high attenuation rate in multiple octaves; through such differentiated filter design and parameter configuration based on the transfer function mathematical model, the filter of each subsystem only presents a low impedance path to the noise of its own frequency band, and presents a high impedance to the noise frequency band of other subsystems, so as to realize frequency spectrum isolation at the physical level, and fundamentally avoid the cross coupling of noise energy between subsystems through the power supply network or ground wire.

[0032] As a preferred embodiment, in step S3, the three-level electromagnetic compatibility model further includes: analyzing the influence of the transient electromagnetic environment on the system through the front door coupling and the back door coupling by establishing a system model, and calculating and distributing the sensitivity threshold index of the components inside the robot according to the analysis; Specifically, by establishing a system model for early simulation analysis, and scientifically allocating the sensitivity threshold of each level component, the quantitative and accurate cooperation of cross-level electromagnetic compatibility design is realized. In implementation, first, a system-level electromagnetic model of the robot needs to be established, which needs to include all key components and their interconnection relationships, and particularly define the front-door coupling paths of electromagnetic interference such as antennas, sensor ports and back-door coupling paths such as power lines, cable shields, and grounding paths. Based on this model, through simulation analysis, it is calculated how the external standard transient electromagnetic disturbance, such as the electric fast transient burst or surge, propagates to the system interior through the defined coupling paths. Then, according to the overall functional performance requirements of the robot, the tolerance index of electromagnetic interference is decomposed into the generalized performance output requirements. Using the model, the sensitivity threshold index of each key element such as the master chip, force sensor, and each subsystem such as the motor driver, communication module is deduced and allocated, which is usually in the form of the strength of the interference signal, ensuring that the component functions normally when the interference is below the threshold. This allocation process of the sensitivity threshold provides clear quantitative design targets for element-level shielding design, subsystem-level PCB layout optimization, and whole-machine shielding design, such as the shielding effectiveness that the element-level shielding cover needs to achieve, the isolation degree that the PCB ground plane needs to achieve, and the transfer impedance that the whole-machine metal shell gap needs to achieve, which need to meet the allocated sensitivity threshold. Through this early index allocation based on model analysis, the three-level electromagnetic compatibility design from the element to the subsystem to the whole machine is no longer isolated measures, but is cooperatively designed and verified under unified and quantitative electromagnetic boundary conditions, ensuring that the design interfaces at each level match and together constitute an organic whole defense system, thereby maximizing the avoidance of potential electromagnetic compatibility risks at the beginning of system design.

[0033] As a preferred embodiment, in step S1, the cylindrical shell of the dynamic following electromagnetic shielding structure is provided with at least one fixing claw, which extends radially outward and then extends axially away from the direction of the stepped shielding cover, so as to realize detachable connection with the shell of the rotary joint. The reliable and convenient detachable connection between the stepped shielding cover and the rotary joint shell is realized through a special fixed claw structure; the fixed claw is a metal protrusion directly extending from the open end of the cylindrical shell of the stepped shielding cover, and is integrally stamped with the shielding cover body to ensure structural strength and continuous conductivity, and the specific form of each fixed claw is that it is first curved and extended along the radial direction of the shielding cover to form a cantilever beam type support part, and then the end of the support part is bent by nearly 90 degrees in the direction away from the shielding cover body, thereby forming a hook-shaped structure similar to the letter L; during installation, the shielding cover is aligned with the annular clamping groove pre-processed on the inner wall of the rotary joint shell, and the axial bending part of the fixed claw is elastically deformed and slid into the clamping groove by applying axial pressure, and when the hook-shaped end of the fixed claw completely passes over the edge of the clamping groove, the hook-shaped end is clamped into the bottom of the clamping groove by the elastic recovery force of the metal itself, and a clear click sound indicates that the installation is in place; this design enables the shielding cover to be firmly locked in the joint shell, which can withstand the vibration and centrifugal force generated during joint rotation to prevent loosening, and when the encoder needs to be maintained, the support part of the fixed claw is elastically deformed by a tool to be disengaged from the clamping groove, realizing non-destructive and rapid disassembly, greatly facilitating maintenance work.

[0034] As a preferred embodiment, in step S3, the cross-level electromagnetic compatibility collaborative design further includes a software anti-interference strategy based on a robust controller, which minimizes the H∞ norm of the closed-loop transfer function of external interference to the system generalized performance output by establishing a state space expression of the joint control system to construct a high-robustness controller that suppresses system model uncertainty and external electromagnetic disturbance; The software algorithm based on H∞ robust control theory is introduced to enhance the intrinsic suppression ability of the system to external electromagnetic disturbance, and the strategy first needs to establish a state space expression model of the joint control system, which is in the form of a state equation: and an output equation , wherein represents system state variables such as joint angle and angular velocity, represents control input such as motor driving voltage, represents disturbance input such as external electromagnetic interference, represents system output, A, B, , C are corresponding system matrix, control matrix, disturbance input matrix and output matrix; In implementation, the control engineer first obtains the nominal model parameters of the controlled object joint motor through system identification or physical modeling method to determine the matrices A and B, and analyzes the possible injection points of electromagnetic interference to determine the disturbance input matrix ; Subsequently, a generalized controlled object is constructed, and the external interference The system's generalized performance output z typically includes a closed-loop transfer function that is a weighted combination of tracking error, control input, and other factors. The H∞ norm is used as a performance indicator, and the design goal of the controller is to solve an output feedback control law. This makes the closed-loop system stable and minimizes the H∞ norm of the transfer function from d to z, which is transformed into solving two algebraic Riccati equations or linear matrix inequalities to obtain the controller. State space implementation; Finally, this H∞ robust controller algorithm was compiled into code and embedded into the digital signal processor of the joint actuator for execution. This controller can automatically compensate for model parameter perturbations caused by electromagnetic interference and has a strong attenuation capability for disturbances in specific frequency bands. Thus, it builds a highly robust defense at the software level to suppress the uncertainty of the system's own model and external electromagnetic disturbances, complementing the hardware electromagnetic compatibility measures.

[0035] In a preferred embodiment, in step S3, the surface of the robot's metal shell is coated with an electromagnetic shielding coating. The electromagnetic shielding coating is composed of conductive fillers and polymer resin, and the electromagnetic shielding coating forms a continuous conductive coating. The overall shielding effectiveness is enhanced by forming a continuous conductive layer on the surface of the metal shell using a functional composite material coating. In practice, the selected electromagnetic shielding coating is composed of conductive fillers and a polymer resin matrix. The conductive fillers are typically flake-structured silver or nickel powder with a specific particle size distribution to facilitate the formation of a denser conductive network within the coating. The polymer resin is selected from materials with good adhesion and environmental resistance, such as epoxy resin or polyurethane. Before coating, the robot's metal shell surface must undergo rigorous sandblasting or chemical treatment to achieve the specified cleanliness and roughness, ensuring coating adhesion. The coating process can employ high-pressure airless spraying or electrostatic spraying. By precisely controlling the spraying pressure, spray gun movement speed, and coating viscosity, a uniform and complete wet film is formed on the shell surface and its complex geometries, including gaps and cable opening edges. Subsequently, curing is performed in a curing oven according to a specified temperature and time curve, allowing the resin matrix to cross-link and solidify, firmly bonding the conductive fillers, ultimately forming a continuous, dense conductive coating of a predetermined thickness. The coating, together with the metal casing substrate, forms a complete conductor. Its surface resistivity needs to be controlled within a low range to effectively reflect and absorb high-frequency electromagnetic waves.

[0036] The above describes the working principle of the electromagnetic interference resistance design method for wheeled humanoid robots in this industrial scenario.

Claims

1. A design method for electromagnetic interference resistance of wheeled humanoid robots in industrial scenarios, characterized in that, Includes the following steps: S1. Construct a dynamic following electromagnetic shielding structure, wherein the dynamic following electromagnetic shielding structure is configured as a stepped shielding cover for the encoder magnetic ring inside the robot's rotary joint, and a Faraday cage is formed through the stepped shielding cover; S2. Establish a hybrid drive heterogeneous spectrum filtering system, and design independent power supply and filtering for the wheel drive system and leg joint drive system of the robot. S3. Implement cross-level electromagnetic compatibility collaborative design and establish a three-level electromagnetic compatibility model to carry out electromagnetic compatibility collaborative design at the component level, subsystem level and whole machine level of the robot respectively. S4. Optimize the overall cable wiring and grounding system. The internal wiring strategy of the robot adopts layered bundling and directional wiring. The robot also has a hybrid grounding model, which includes low-frequency circuits and high-frequency circuits. The low-frequency circuits adopt single-point grounding, and the high-frequency circuits adopt multi-point grounding. The robot's subsystems are connected to the central grounding point through a low-impedance grounding bus.

2. The electromagnetic interference resistance design method for wheeled humanoid robots in industrial scenarios according to claim 1, characterized in that: In step S1, the Faraday cage remains dynamically intact as the rotary joint moves. The Faraday cage is configured such that one side of the stepped shield is connected to the encoder, and the other side of the stepped shield is connected to the outer shell of the rotary joint via elastic contacts. The stepped shield rotates synchronously with the encoder.

3. The electromagnetic interference resistance design method for wheeled humanoid robots in industrial scenarios according to claim 1, characterized in that: In step S2, the power line of the wheel drive system is configured with a high-current common-mode choke and a differential-mode π-type filter to suppress low-frequency conducted interference, and the power line of the foot joint drive system is configured with a three-segment capacitor filter and a ferrite magnet to suppress mid-to-high frequency switching noise.

4. The electromagnetic interference resistance design method for wheeled humanoid robots in industrial scenarios according to claim 1, characterized in that: In step S3, the electromagnetic compatibility collaborative design specifically includes: At the component level, the robot's force sensors and communication modules are partially shielded; At the subsystem level, the printed circuit board layout of the robot is optimized to separate high-frequency digital circuits from analog circuits and adopt independent grounding strategies. At the overall machine level, the robot's shielding layer is made of a metal shell, and electromagnetic sealing gaskets are used to treat the gaps in the metal shell and the cable openings.

5. The electromagnetic interference resistance design method for wheeled humanoid robots in industrial scenarios according to claim 2, characterized in that: In step S1, the stepped shield is made of permalloy, and the dynamic following electromagnetic shielding structure includes an inner conductive pad and an outer magnetic shielding layer. The inner conductive pad is made of a composite structure of metal woven mesh and conductive rubber, so that the stepped shield and the shell of the rotating joint make low-impedance contact.

6. The electromagnetic interference resistance design method for wheeled humanoid robots in industrial scenarios according to claim 1, characterized in that: In step S2, the heterogeneous spectrum filtering system is characterized by using filters with different frequency attenuation characteristics according to the different noise spectrum characteristics of the wheel drive system and the joint drive system, thereby avoiding cross-coupling of noise between the subsystems.

7. The electromagnetic interference resistance design method for wheeled humanoid robots in industrial scenarios according to claim 1, characterized in that: In step S3, the three-level electromagnetic compatibility model further includes: analyzing the impact of transient electromagnetic environment on the system through front-door coupling and back-door coupling by establishing a system model, and calculating and allocating sensitivity threshold indicators for the components inside the robot accordingly.

8. The electromagnetic interference resistance design method for wheeled humanoid robots in industrial scenarios according to claim 2, characterized in that: In step S1, the cylindrical housing of the dynamic following electromagnetic shielding structure is provided with at least one fixing claw. The fixing claw extends radially outward and then axially away from the stepped shielding cover, thereby achieving a detachable connection with the housing of the rotating joint.

9. The electromagnetic interference resistance design method for wheeled humanoid robots in industrial scenarios according to claim 1, characterized in that: In step S3, the cross-level electromagnetic compatibility collaborative design also includes a software anti-interference strategy based on a robust controller. By establishing the state-space expression of the joint control system, the H∞ norm of the closed-loop transfer function from external interference to the generalized performance output of the system is minimized to construct a highly robust controller that suppresses the uncertainty of the system's own model and external electromagnetic disturbances.

10. The electromagnetic interference resistance design method for wheeled humanoid robots in industrial scenarios according to claim 4, characterized in that: In step S3, the surface of the robot's metal shell is coated with an electromagnetic shielding coating, which is composed of conductive fillers and polymer resin, and forms a continuous conductive coating.

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