Automobile wire harness automatic assembly method and system based on same

Abstract

The application relates to the technical field of automobile wire harness assembly, and discloses an automobile wire harness automatic assembly method and system. The method is based on the electrical architecture topology of a target vehicle model to construct a wire harness path model, which contains a branch point coordinate sequence and a bending radius constraint; then a tooling equipment model is constructed to simulate the action timing of a wire clamp installation robot and a wire crimping device in the wire harness assembly process; subsequently, according to selected assembly working condition parameters, the tooling equipment model and the wire harness path model are subjected to space coupling simulation to generate an assembly trajectory sequence; finally, based on the interference detection result of the assembly trajectory sequence, it is determined whether the current assembly scheme has an interference risk. Through precise modeling and coupling simulation, the method can troubleshoot assembly interference problems in advance, optimize the assembly process, is suitable for efficient and precise assembly of automobile wire harnesses, and helps to improve the assembly quality and production efficiency of automobile wire harnesses.

Description

Technical Field

[0001] This invention relates to the field of automotive wiring harness assembly technology, specifically to an automatic assembly method and system based on automotive wiring harness fabric. Background Technology

[0002] As the automotive industry rapidly develops towards intelligence and electrification, the complexity of automotive electrical systems has increased significantly, and the corresponding automotive wiring harnesses are also characterized by multi-branching, high density, and long dimensions. As the core carrier connecting various electrical components of a vehicle, the assembly quality of automotive wiring harnesses directly affects the stability and safety of the automotive electrical system, thus placing higher demands on the precision and efficiency of wiring harness assembly.

[0003] In current automotive wiring harness assembly processes, traditional methods rely heavily on manual experience for path planning and tooling adjustments. During path planning, manual methods roughly determine the wiring harness route based on the target vehicle's electrical architecture, making it difficult to precisely quantify branch point locations and bending radii. This leads to problems such as twisting and stretching of the wiring harness during actual assembly, affecting assembly efficiency and potentially shortening its lifespan due to stress concentration. Furthermore, wiring harness assembly involves various tooling devices, such as wire clip installation robots and wire crimping equipment. The timing of these devices' actions requires manual coordination. Due to the lack of precise simulation of the equipment's movements, conflicts between devices can easily occur. For example, the clamping action of the wire clip installation robot and the feeding action of the wire crimping equipment may overlap spatially, causing equipment collisions or assembly interruptions, increasing the risk of failure during production.

[0004] To improve assembly automation, some companies have attempted to introduce simulation technology, but existing simulation solutions have significant limitations. On one hand, the simulation process does not fully incorporate actual assembly parameters, such as the hardness of wiring harness materials for different vehicle models and the impact of ambient temperature on equipment movement speed. This results in a disconnect between the simulated assembly trajectory and the actual production scenario, limiting the reference value of the simulation results. On the other hand, existing simulations often focus solely on wiring harness paths or tooling equipment, failing to achieve spatial coupling between the two. This makes it impossible to comprehensively detect potential interference problems during assembly, such as spatial overlap between wiring harnesses and equipment components, or collisions between wiring harness branches and the vehicle body structure. These issues make it difficult to identify potential risks before practical application of the assembly solution, often requiring repeated adjustments during production. This not only prolongs the production cycle but also wastes raw materials and labor costs, failing to meet the automotive industry's demands for large-scale, high-efficiency production. Summary of the Invention

[0005] The purpose of this invention is to provide an automatic assembly method based on automotive wiring harness fabric to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides an automatic assembly method based on automotive wiring harness fabric, the method comprising:

[0007] A wiring harness path model is constructed based on the electrical architecture topology of the target vehicle model. The wiring harness path model includes a sequence of branch point coordinates and bending radius constraints.

[0008] Construct a tooling equipment model, which is used to simulate the action sequence of the wire clamp installation robot and the wire crimping equipment during the wire harness assembly process;

[0009] Based on the selected assembly condition parameters, a spatial coupling simulation is performed on the tooling equipment model and the wire harness path model to generate an assembly trajectory sequence.

[0010] Based on the interference detection results of the assembly trajectory sequence, it is determined whether there is an interference risk in the current assembly scheme.

[0011] Preferably, when the electrical architecture topology includes engine compartment wiring harness branches, dashboard wiring harness branches, and door wiring harness branches, the wiring harness path model construction based on the electrical architecture topology of the target vehicle includes:

[0012] Based on the electrical architecture topology, a set of three-dimensional coordinates is generated for the engine compartment branch path segment, the instrument panel branch path segment, and the door branch path segment.

[0013] The engine compartment branch path segment is connected to the main trunk segment of the main wiring harness path model through transition surface constraints, the dashboard branch path segment is connected to the main trunk segment through rigid fixed point constraints, and the door branch path segment is connected to the main trunk segment through flexible swing constraints to construct and obtain the wiring harness path model.

[0014] Preferably, the step of performing spatial coupling simulation of the tooling equipment model and the wiring harness path model based on the selected assembly condition parameters includes:

[0015] Based on the selected wire diameter parameters, the pressure command is output through the wire tension control strategy model to control the crimping torque of the wire crimping device in the tooling equipment model;

[0016] When the wire crimping device reaches the preset torque threshold, the displacement command is output by the branch positioning strategy model to control the position offset of the branch point in the wire harness path model, so as to realize the motion coordination between the path model and the device model.

[0017] Preferably, prior to the spatial coupling simulation, the method further includes:

[0018] The displacement signal with a step change is input to the path correction port of the branch positioning strategy model to calibrate the branch path smoothness control parameters.

[0019] When the rate of change of curvature of the branch path meets the preset smoothness requirement, the step-change pressure signal is input to the tension port of the conductor tension control strategy model to calibrate the conductor deformation compensation parameters.

[0020] When the deviation between the conductor deformation compensation parameters and the physical test data is less than the allowable tolerance, a tooling equipment model capable of performing coupled simulation is obtained.

[0021] Preferably, determining whether the current assembly scheme has an interference risk includes:

[0022] When the assembly trajectory sequence meets the first preset condition or the second preset condition, it is determined that there is a risk of interference.

[0023] The first preset condition is that the number of times the instantaneous value of the bending radius of the wire harness path model in the spatial coupling simulation is less than the minimum bending radius of the material exceeds a set threshold.

[0024] The second preset condition is that the spatial distance between the wire harness branch path segment and the adjacent sheet metal part is lower than the safety gap for two consecutive simulation cycles.

[0025] Preferably, the method further includes:

[0026] When there is a risk of interference, optimize the timing parameters of the wire crimping equipment in the tooling equipment model;

[0027] Based on the optimized action timing parameters, the spatial coupling simulation is re-executed until the interference detection result of the assembly trajectory sequence does not meet the first preset condition and the second preset condition.

[0028] Preferably, the engine compartment branch path segment is constructed, including:

[0029] Based on the distribution of high-temperature areas in the engine compartment, the wiring harness branches in the engine compartment are discretized into heat-resistant material sections and non-heat-resistant material sections.

[0030] The heat-resistant material section and the non-heat-resistant material section are connected by a thermal expansion compensation algorithm, and temperature gradient change parameters are set.

[0031] Preferably, the construction of the dashboard branch path segment includes:

[0032] Using the mounting holes inside the instrument panel as reference points, the instrument panel wiring harness branches are divided into rigid fixed sections and movable allowance sections.

[0033] The spatial coordinates of the rigid fixed section are locked to the vehicle body coordinate system, and the movable margin section is connected to the rigid fixed section through an elastic deformation algorithm.

[0034] Preferably, the optimized timing parameters of the wire crimping equipment include:

[0035] Extract the time sequence in which the wire crimping torque exceeds the material yield strength in the spatial coupling simulation;

[0036] Based on the branch point displacement data corresponding to the time sequence, the slope of the pressure rise curve of the wire crimping device is reversed.

[0037] Preferably, the present invention also includes an automatic assembly system based on automotive wiring harnesses, including a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor, when executing the computer program, implements the steps of the above-described automatic assembly method based on automotive wiring harnesses.

[0038] Compared with the prior art, the beneficial effects of the present invention are:

[0039] This automated assembly method for automotive wiring harnesses provides a reliable foundation for subsequent assembly processes by constructing a precise wiring harness path model. This model, based on the electrical architecture topology of the target vehicle, explicitly includes branch point coordinate sequences and bending radius constraints. It accurately quantifies the position and morphological parameters of each key node in the wiring harness, avoiding the non-standard wiring harness shape issues caused by experience biases in traditional manual path planning. This ensures that the wiring harness is arranged strictly according to the preset path during assembly, reducing wiring harness twisting and stretching, guaranteeing the structural stability of the assembled wiring harness, and providing a clear target benchmark for the motion planning of subsequent tooling equipment.

[0040] The construction of the tooling equipment model enables the simulation of the timing of actions of the wire clamp installation robot and the wire crimping equipment, breaking the limitations of traditional manual coordination of equipment actions. This model allows for the complete presentation of the action processes of both devices in a virtual environment, clearly displaying the position, posture, and trajectory of the equipment at different time points. This facilitates the early detection of unreasonable timing in the equipment actions, such as whether the time interval between the wire clamp installation robot completing its clamping action and the wire crimping equipment initiating its crimping action is reasonable, or whether the equipment movement speeds are matched. This optimizes the equipment action logic, avoids collisions or assembly interruptions caused by conflicting actions between devices during actual assembly, and improves the coordination and stability of the tooling equipment operation.

[0041] Spatial coupling simulation of the tooling equipment model and the wire harness path model based on assembly condition parameters further improves the practicality and accuracy of the assembly scheme. The assembly condition parameters cover key factors in actual production, such as wire harness material characteristics and assembly environmental conditions. Integrating these parameters into the simulation process ensures that the simulation scenario closely matches the actual production scenario, and the generated assembly trajectory sequence is more instructive. Simultaneously, spatial coupling simulation realizes the synchronous motion simulation of the wire harness and tooling equipment in virtual space, comprehensively presenting their spatial positional relationship during the assembly process. Compared to traditional standalone simulation methods, it can more comprehensively capture potential interference risk points, providing comprehensive simulation data support for subsequent interference detection.

[0042] Interference detection based on assembly trajectory sequences identifies interference risks in the current assembly scheme, enabling early detection of problems before actual production. Interference detection accurately identifies spatial interference between wiring harnesses and tooling equipment, between wiring harnesses and the vehicle body structure, and even between individual branches of the wiring harness. For example, it can detect whether a branch of the wiring harness will collide with the robotic arm of the wire clamp installation robot during bending, or whether the wire crimping equipment will squeeze the wiring harness during feeding. Early detection of these problems allows for timely adjustments to the assembly scheme, such as optimizing the branch point positions of the wiring harness path and adjusting the timing or trajectory of tooling equipment. This eliminates the need for repeated trial and error adjustments during actual production, effectively shortening the debugging cycle of the assembly scheme, reducing waste of raw materials due to assembly errors, and lowering the probability of equipment failures and safety accidents during production. This ensures the continuity and stability of automotive wiring harness assembly, thereby improving the overall efficiency of automotive production. Attached Figure Description

[0043] Figure 1 This is a schematic diagram illustrating the working principle of an automatic assembly method for automotive wiring harnesses as described in this invention.

[0044] Figure 2 Flowchart illustrating the working principle of constructing a harness path model for electrical architecture topology;

[0045] Figure 3 A flowchart illustrating the working principle of spatial coupling simulation between tooling equipment model and wiring harness path model;

[0046] Figure 4 A flowchart illustrating the working principle of determining interference risk based on sequence interference detection results. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] Please see Figure 1 This invention provides an automatic assembly method and system based on automotive wiring harness fabric, the method comprising:

[0049] Based on the electrical architecture topology of the target vehicle model, a wiring harness path model is constructed. This model includes a branch point coordinate sequence and bending radius constraints to ensure the geometric accuracy of the wiring harness path. The branch point coordinate sequence is defined using a three-dimensional coordinate system, and the bending radius constraints are set based on the physical properties of the wiring harness material to prevent excessive bending. A tooling equipment model is constructed to simulate the timing of the actions of the wire clip installation robot and the wire crimping equipment during the wiring harness assembly process. The timing of the actions includes the robot's movement path and the pressure application sequence of the crimping equipment to reflect the actual assembly process. Based on selected assembly condition parameters, such as wire diameter and ambient temperature, a spatial coupling simulation is performed on the tooling equipment model and the wiring harness path model. The spatial coupling simulation dynamically combines the equipment actions with the wiring harness path using mathematical algorithms to generate an assembly trajectory sequence, which represents the movement path of the wiring harness and equipment during the assembly process. Interference detection is performed based on the assembly trajectory sequence to analyze the spatial relationship between the wiring harness and surrounding components (such as sheet metal parts) to determine whether there is an interference risk in the current assembly scheme. Interference detection uses a collision detection algorithm to calculate the minimum distance and instantaneous bending radius values ​​to assess the risk.

[0050] Example 1: See Figure 2 In a specific implementation scenario, taking the automated assembly process of a certain model of passenger vehicle wiring harness as an example, this paper elaborates on the method of constructing a wiring harness path model. The electrical architecture topology of the target vehicle includes three main wiring harness branch areas: the engine compartment, the dashboard, and the doors. The implementation process begins with extracting electrical layout data from the vehicle design database. This data exists in 3D point cloud and CAD model formats, containing the location of electrical components, connection relationships, and vehicle body structure information.

[0051] Based on the electrical architecture topology, a set of three-dimensional coordinates for branch path segments in the engine compartment is generated. This coordinate set generation relies on a digital mapping of the engine compartment space. By reading the installation coordinates of electrical components such as the engine ECU, fuse box, headlights, and sensors, path points are inserted between these points according to wiring principles, forming a preliminary path sequence. Considering the complex environment of the engine compartment, including high temperatures and vibrations, the coordinate points are collected not only with spatial location information but also with environmental attribute labels. For example, the area near the engine body is marked as a high-temperature zone, and the coordinate point set in this area uses a higher collection density. These coordinate points are input into the path generation algorithm, which uses a nonlinear interpolation method to generate smooth, continuous path segments, where each path point records its three-dimensional coordinates, curvature estimate, and ambient temperature attribute.

[0052] The generation of coordinate sets for the dashboard branch path segments prioritizes spatial compactness and assembly accessibility. Constrained by the limited space behind the dashboard, it obtains mounting hole positions, support beam structures, and existing component boundary data from the vehicle body coordinate system. The coordinate point generation process employs an obstacle avoidance algorithm, automatically bypassing obstacles such as air conditioning ducts and brackets to form a circuitous path sequence that meets the minimum bending radius requirement. All coordinate points in this path segment are associated with the vehicle body's fixed structure to ensure path stability.

[0053] The coordinate generation of the door branch path segment needs to consider dynamic motion characteristics. Starting from the hinge axis coordinates, the swing range of the wiring harness is calculated based on the door opening and closing trajectory model. The coordinate set is generated using a kinematic simulation-assisted method, collecting key points of the path in three states: maximum door opening, half-open, and closed. These points are then connected into dynamic path segments using a time series algorithm. These coordinate points not only contain spatial information but also record the corresponding door opening and closing angle parameters.

[0054] After obtaining the 3D coordinate set of each branch path segment, the path model is integrated and constructed. The engine compartment branch path segment is connected to the main trunk segment of the main wiring harness through a transition surface constraint. This transition surface constraint is implemented using the surface generation tool in the computer-aided design system. A continuously varying hyperbolic transition surface is constructed using the coordinates of the end of the main trunk segment and the starting coordinates of the engine compartment branch as boundary conditions. The algorithm for generating this surface includes tangent direction consistency verification and curvature continuity checks to ensure that there are no abrupt changes or distortions at the connection points. Multiple control points are automatically inserted inside the surface. The coordinates of these control points are adaptively adjusted according to the geometry of adjacent sheet metal parts, always maintaining a minimum safe distance from the metal components.

[0055] The dashboard branch path segment is connected to the main section via rigid fixed-point constraints, which are based on existing mounting holes found within the dashboard. Precise positioning coordinates of these mounting holes are extracted from the vehicle body design database, and corresponding points on the branch path segment are forcibly aligned with these coordinates. In the 3D model, these alignment points are subject to degree-of-freedom constraints, with all six spatial degrees of freedom (three translations and three rotations) fully locked, making this path segment a rigid reference frame for the entire wiring harness system. Appropriate slack is maintained between the rigid fixed points, and elastic segments are inserted between each fixed point using parametric design methods. The length and orientation of these segments are calculated and adjusted based on the differences in the thermal expansion coefficients of adjacent components.

[0056] The door branch path segment is connected to the main segment via a flexible swing constraint, which is implemented using a kinematic dynamic model. A local coordinate system is established with the door hinge center as the origin of rotation. Key points on the branch path are assigned corresponding motion parameters, including the swing angle range, angular velocity threshold, and acceleration limit. In the path model, these points are not fixed coordinates but exist as functions, and their positions are dynamically calculated as the door state changes. The geometry at the connection point uses a flexible material deformation algorithm to simulate the torsional and bending characteristics of the rubber sleeve. A buffer zone is set at the junction of the main segment and the door segment. The coordinates of the path points in this zone are interpolated in real time based on the door opening and closing angle to form a smooth transition motion trajectory.

[0057] After the entire wiring harness path model is constructed, a global bending radius verification is performed. The instantaneous radius of curvature at each point on the path is calculated using a differential geometry algorithm and compared with the minimum allowable value in the material database. For the high-temperature area of ​​the engine compartment, the bending radius standard of high-temperature resistant materials is adopted; for the dynamic area of ​​the door, the radius standard corresponding to multiple bending fatigue life is adopted. When any area that does not meet the requirements is found, the process returns to the coordinate adjustment stage, and the coordinate points of that area are regenerated using a local path optimization algorithm until all constraints are met.

[0058] The final obtained wiring harness path model is a comprehensive digital model that includes spatial geometric information, material properties, motion parameters, and environmental conditions. This model not only reflects the static geometric characteristics of the wiring harness but also includes dynamic behavior characteristics, and can realistically simulate the spatial state and motion performance of the wiring harness in a real vehicle environment.

[0059] Example 2: See Figure 3In implementing automated assembly methods for automotive wiring harnesses, the execution of spatial coupling simulation and preliminary parameter calibration are crucial steps. Taking the wiring harness assembly process of a certain SUV model as an example, this model employs a complex multi-branch wiring harness system with various wire types, including power cables, signal wires, and grounding wires. The selection of assembly condition parameters is based on the actual configuration of this vehicle model. Wire diameter parameters are extracted from a material library, including different specifications such as 0.5 square millimeter signal wires and 2.5 square millimeter power wires. Environmental parameters are set to standard operating conditions of 25 degrees Celsius room temperature and 60% humidity. These parameters are input into the wire tension control strategy model, which is built based on a material mechanical property database and includes parameters such as the elastic modulus, yield strength, and creep characteristics of the wire material.

[0060] The operating mechanism of the conductor tension control strategy model is as follows: Upon receiving the conductor diameter parameter, the model first calculates the minimum bending radius and maximum allowable tension of the conductor of that specification. Then, based on the crimping process requirements, it generates a corresponding pressure command sequence. These commands are output in the form of digital signals to control the crimping torque of the conductor crimping equipment in the tooling equipment model. The crimping torque control adopts a closed-loop adjustment method, comparing the difference between the actual torque value and the target value in real time, and adjusting the output pressure through a proportional-integral algorithm. The pressure command generation strategy differs for conductors of different diameters: a slow pressure increase strategy is used for thinner diameter conductors, while a rapid attainment of the predetermined pressure value is required for thicker diameter conductors.

[0061] When the wire crimping device reaches a preset torque threshold, the system triggers the branch positioning strategy model. This threshold is determined based on the wire material and diameter; for example, the torque threshold is 0.8 Nm for a 0.5 mm² signal wire and 2.5 Nm for a 2.5 mm² power wire. The branch positioning strategy model then calculates the positional offset of the branch points in the harness path model. The calculation process considers the influence of wire tension variations on the path shape, using finite element analysis to simulate the deformation characteristics of the wire under stress. Displacement commands are generated based on deformation prediction results, guiding the branch points to make corresponding positional adjustments. This adjustment ensures that the harness path maintains a reasonable geometry during crimping, avoiding excessive bending or stretching.

[0062] Spatial coupling simulation is performed using a dedicated simulation platform that simultaneously runs the tooling equipment model and the wiring harness path model, establishing a data exchange channel between them. The simulation time step is set to 0.01 seconds, with one equipment state update and path shape calculation completed within each step. During the simulation, the timing of the wire crimping device's actions is synchronized with the branch point's position adjustment, forming a dynamic coordinated motion. This coordination is achieved through real-time data interaction: the equipment model sends the current crimping torque value to the path model, the path model returns the corresponding deformation data, and the equipment model adjusts its next action parameters accordingly. Before conducting spatial coupling simulation, system parameter calibration is required, starting with branch path smoothness control. A step-change displacement signal is input to the path correction port of the branch positioning strategy model; this signal simulates sudden position changes that may occur during assembly. The system records the branch path's response characteristics to this input, including the rate of change of path curvature and oscillation amplitude. By analyzing this response data, smoothness control parameters, such as the filter coefficient and response delay time, are adjusted to ensure that the branch path can quickly recover to a stable state after being disturbed, without overshooting or oscillation.

[0063] Once the curvature change rate of the branch path meets the preset smoothness requirement, the calibration of the conductor deformation compensation parameters is performed. A step-change pressure signal is input to the tension port of the conductor tension control strategy model to simulate the sudden application of pressure by the crimping equipment. The system monitors the conductor's deformation response under this impact pressure and records the proportional relationship between elastic and plastic deformation. By repeatedly applying step pressures of different amplitudes, the deformation characteristic curves of the conductor under different stress states are obtained.

[0064] The deformation data obtained from simulation were compared and analyzed with physical test data. The physical test data came from actual laboratory measurements, using the same wire samples under the same working conditions for crimping tests, and the three-dimensional deformation data of the wires were recorded using a laser scanner. Statistical analysis was used in the comparison process to calculate the deviation index between the simulation data and the measured data. When the deviation exceeded the allowable tolerance, the wire deformation compensation parameters were adjusted, including the material's elastic modulus, damping characteristics, and relaxation rate. The adjustment process employed an iterative optimization method, rerunning the step response test after each parameter modification until the deviation between the simulation results and the physical test data was controlled within the allowable range.

[0065] After all parameters were calibrated, a tooling equipment model capable of performing coupled simulations was obtained. This model possesses the ability to accurately simulate the behavior of actual equipment and reflects various physical phenomena during wire crimping. The model includes a validated parameter set, ensuring a high degree of consistency between the simulation results and actual conditions. At this point, the tooling equipment model can be reliably coupled spatially with the wire harness path model, providing an accurate foundation for subsequent assembly trajectory generation and interference detection. The entire implementation process embodies a complete workflow from parameter calibration to simulation execution, ensuring the accuracy and reliability of the simulation model through a systematic approach.

[0066] Example 3: See Figure 4 In the process of interference risk analysis of the implementation of the automatic assembly scheme for automotive wiring harnesses, a dynamic detection method based on assembly trajectory sequence is adopted. This implementation method is for the complex wiring harness system of a certain type of hybrid vehicle. Its characteristics are that there is a mixed wiring of high-voltage cables and low-voltage signal lines in the engine compartment, and the instrument panel area is compact, which requires high assembly accuracy.

[0067] The assembly trajectory sequence originates from the output of spatial coupling simulation. This sequence records the spatial coordinate changes of each feature point on the harness path model throughout the assembly process in the form of timestamps, and also includes the attitude data of the robotic arm end effector and crimping tool in the tooling equipment model. The sequence data is sampled at 0.01-second intervals to continuously record the dynamic changes throughout the assembly process.

[0068] Interference detection is first implemented under the first preset condition. The minimum bending radius of the material is determined based on a database of the physical properties of the wire harness material. For high-voltage cables, a standard of 2.5 times the cable outer diameter is used, while for low-voltage signal lines, a standard of 3 times the cable diameter is used. During the simulation, the system calculates the instantaneous radius of curvature at each point along the wire harness path in real time. The calculation formula is as follows:

[0069]

[0070] in: Represents the instantaneous radius of curvature at time point t. Let this be the instantaneous velocity vector of the point on the path of the wire harness. This corresponds to the instantaneous acceleration vector. The calculation is based on differential geometry principles and is obtained through the first and second derivatives of the path parametric equations. The system sets a risk threshold of 5 occurrences; that is, when the instantaneous bending radius of any segment of the wiring harness path is less than the material's minimum bending radius more than 5 times cumulatively, an interference risk warning is triggered. During implementation, the system records the time, location coordinates, and actual bending radius value of each violation event, forming a detailed event log.

[0071] The second preset condition focuses on the spatial relationship between the wiring harness branches and surrounding sheet metal parts. The safety clearance is set according to automotive industry standards: power wiring harnesses should maintain a distance of at least 5 mm from metal components, and signal wiring harnesses at least 3 mm. The spatial distance is calculated using a nearest-point search algorithm, calculating the Euclidean distance between each point on the wiring harness surface and the surface of adjacent sheet metal parts within each simulation frame.

[0072] The judgment condition of two consecutive simulation cycles means that the distance violation needs to be maintained for 0.02 seconds. This avoids false alarms caused by instantaneous calculation errors or slight jitter. When the system detects a distance violation, it will record the start time of the violation, the duration, the minimum distance value, and the numbers of the wire harness segments and sheet metal parts involved.

[0073] When the assembly trajectory sequence meets any preset condition, the system generates an interference risk report, which includes detailed information such as the risk type, location, severity, and duration. For violations of bending radius, the system also marks the specific affected wire harness segment and the maximum violation amplitude. After confirming the existence of interference risk, the system enters the optimization phase, optimizing the timing parameters of the wire crimping equipment in the tooling model. These parameters include key indicators such as pressure rise time, holding time, and pressure release rate. The optimization process first analyzes the temporal distribution characteristics of interference events to identify the correlation between the crimping action and the occurrence of interference.

[0074] For the assembly of high-voltage wiring harnesses in the engine compartment, the optimization focus is on adjusting the synchronization between the movement speed of the crimping tool and the application of pressure. By reducing the movement speed in confined spaces and optimizing the pressure application curve, the wiring harness maintains a more stable shape during assembly. For low-voltage wiring harnesses in the instrument panel area, optimization measures focus on adjusting the timing of actions between multiple crimping points to avoid excessive bending of the wiring harness due to improper sequence.

[0075] The optimized timing parameters need to be re-input into the spatial coupling simulation system for verification. The re-simulation uses the same initial conditions and operating parameters to ensure comparability of results. During the simulation, the system pays special attention to areas and time points where interference previously occurred, performing focused monitoring. The iterative optimization process continues, generating a new assembly trajectory sequence and performing interference detection after each optimization. The system records the parameter adjustments and corresponding detection results for each optimization, forming an optimization history. The optimization process terminates when no interference risk is detected after three consecutive optimizations, or when the number of optimization iterations reaches the preset maximum (usually set to 10).

[0076] The final optimized solution includes a complete set of action timing parameters and corresponding assembly trajectory sequences. This solution ensures that there is no risk of excessive material bending or interference with surrounding components during wiring harness assembly, providing reliable operational guidance for actual automated assembly operations. The entire implementation process embodies a complete closed loop from risk detection to parameter optimization, improving the reliability and safety of automated automotive wiring harness assembly through a systematic approach.

[0077] Example 4: In the process of constructing the automotive wiring harness path model, different technical methods are required for establishing the branch path segments of the engine compartment and the dashboard. Taking a certain front-engine SUV model as an example, its engine compartment is equipped with a turbocharged engine and a hybrid system, with a complex temperature distribution, while the dashboard area integrates a large number of electronic devices with strict space constraints.

[0078] The construction of the engine compartment branch path segment begins with temperature field data analysis. Thermal imaging tests are used to obtain the temperature distribution of the engine compartment under different operating conditions, and a mapping relationship is established between the temperature data and three-dimensional spatial coordinates. Temperature data acquisition points cover the areas surrounding heat sources such as the engine block, exhaust manifold, turbocharger, and cooling system. Each acquisition point records its spatial coordinates and the corresponding temperature range. Based on this data, the engine compartment wiring harness branches are discretized into heat-resistant material sections and non-heat-resistant material sections. The heat-resistant material sections are mainly distributed within 100 mm of high-temperature components and use silicone rubber insulation; the non-heat-resistant material sections are distributed in lower-temperature areas and use standard PVC insulation.

[0079] The connection between the two sections employs a thermal expansion compensation algorithm. This algorithm is designed based on the difference in the thermal expansion coefficients of the materials. The input parameters include the ambient temperature range, the linear expansion coefficient of the materials, and the section length. During the calculation, the algorithm simulates the difference in expansion of different materials as the temperature changes from low to high, automatically adjusting the coordinates of the connection point to maintain appropriate tension in the wiring harness during thermal expansion and contraction, avoiding excessive stretching or compression. The temperature gradient change parameters are set according to the actual engine operating temperature curve, encompassing various states such as cold start, normal operation, and extreme high-temperature conditions.

[0080] The construction of the instrument panel branch path segment is based on the mounting hole position data. The coordinates of all mounting holes inside the instrument panel are extracted from the vehicle body design database, including fixing bolt holes, clip mounting points, and support structure connection points. Using these hole positions as a reference, the instrument panel wiring harness branches are divided into rigid fixed sections and movable allowance sections. The rigid fixed sections are typically located within a 50mm radius around the mounting holes and are tightly secured; the movable allowance sections are located between two fixed points, allowing for a certain degree of movement and deformation.

[0081] The spatial coordinates of the rigid fixed section are locked to the vehicle coordinate system via a coordinate transformation matrix. The locking process employs six degrees of freedom constraints, completely restricting the translational and rotational motion of the wiring harness at that point, making it a stable reference point for the entire wiring harness path. The movable margin section is connected to the rigid fixed section using an elastic deformation algorithm that simulates the extension and compression behavior of the wiring harness under stress. Algorithm parameters include the elastic modulus of the wiring harness material, the moment of inertia of the section, and the maximum allowable strain value, ensuring that the wiring harness does not exceed the material's safe deformation range during assembly and use. Key parameters for the heat-resistant material section of the engine compartment wiring harness branch are shown in Table 1.

[0082] Table 1: Parameter configuration table for heat-resistant material sections in the engine compartment.

[0083]

[0084] In the actual construction of the engine compartment branch paths, the length and position of each section need to be adjusted according to the specific engine compartment layout of the vehicle model. For example, the turbocharger section needs to avoid the high-temperature exhaust manifold while maintaining a safe distance from rotating parts. The cooling system branch needs to be arranged along the coolant pipe route to avoid interference with moving parts. The construction of the dashboard branch paths needs to consider the complexity of the internal structure. The selection of rigid fixing points prioritizes installation locations with sufficient structural strength, usually choosing the reinforcing beams of the dashboard frame or mounting holes on the fixing brackets. The length design of the movable margin section is based on the distance between adjacent fixing points, generally setting a margin length of 3% to 5% of the fixing point spacing to compensate for dimensional changes caused by manufacturing tolerances and temperature variations.

[0085] The entire construction process was completed using a computer-aided design system. The system automatically checked the gaps between the path and surrounding components, verified whether the bending radius met the requirements, and ensured that all connection points met the mechanical strength and thermal performance requirements. The final generated wire harness path model contained complete geometric information, material properties, and environmental parameters, providing accurate basic data for subsequent assembly simulation and analysis.

[0086] Example 5: In the optimization process of the automatic assembly method for automotive wiring harnesses, adjusting the timing parameters of the wire crimping equipment is a technically demanding step requiring precise operation. This implementation method focuses on the assembly process of high-voltage wiring harnesses for a certain model of electric vehicle. Its characteristics include a large wiring harness diameter, high material strength requirements, and assembly accuracy directly impacting the safety performance of the vehicle's electrical system. The inter-coupled simulation process generates a large amount of operational data. This data records detailed parameters of the entire assembly process in time series form. Extracting the time series where the wire crimping torque exceeds the material yield strength from this data is the starting point for optimization. The material yield strength value comes from the material technical specifications; different specifications of wires have different yield strength thresholds. The data extraction process is completed using a specially developed analysis tool. This tool can scan the entire simulation log, identify all moments when the torque value exceeds the preset threshold, and record the precise timestamps and corresponding torque exceedance amounts for these moments.

[0087] Each identified moment of exceeding the limit is associated with rich contextual data. The system synchronously records the displacement data of each branch point on the harness path model at that moment, including changes in three-dimensional coordinates, movement velocity, and acceleration. This displacement data reflects the deformation state and motion characteristics of the harness at the moment of torque exceeding the limit. Of particular note is the motion trajectory of the branch points before and after the moment of exceeding the limit, as this trajectory data reveals the response mode of the harness under excessive stress.

[0088] Analyzing these displacement data reveals some regularities. For example, certain types of torque overruns are often accompanied by branch point movement in specific directions, or certain areas of the wire harness are more prone to excessive displacement under pressure changes. These regularities provide directional guidance for subsequent parameter optimization. Based on the analysis results, a reverse correction was initiated on the slope of the pressure rise curve of the wire crimping equipment. The pressure rise curve describes the process of the crimping equipment reaching the target pressure from the initial pressure, and its slope determines the rate of pressure increase. The correction process employs an iterative adjustment method, first establishing a model of the correspondence between pressure curve parameters and torque overrun phenomena. This model can predict the impact of different pressure rise rates on the stress state of the wire harness.

[0089] The implementation of reverse correction involves several steps. First, based on the distribution characteristics of the over-limit moments, the stage in the pressure curve that needs adjustment is determined. For early-onset torque over-limits, it is usually necessary to reduce the pressure rise rate in the initial stage; for later-onset over-limits, it may be necessary to adjust the curve shape of the entire pressure rise process. Then, based on the analysis results of the branch point displacement data, the specific adjustment range and method are determined. Areas with larger displacement require more significant pressure curve adjustments, while areas with complex displacement patterns require more refined curve shape optimization. Multiple factors need to be considered comprehensively during the correction process. Reducing the pressure rise rate can decrease the instantaneous torque peak, but may prolong the entire crimping process time. A suitable balance point needs to be found to avoid torque over-limits without significantly affecting assembly efficiency. Furthermore, different specifications of conductors may require different pressure curve parameters, which necessitates a certain degree of adaptability and flexibility in the correction process.

[0090] The corrected pressure curve parameters need to be re-imported into the tooling equipment model for a new round of simulation verification. This process typically requires multiple iterations, with each iteration fine-tuning based on the previous optimization results. After each simulation run, it is necessary to recheck whether the torque values ​​still exceed limits and whether the displacement of the branch points has improved. Throughout the optimization process, data recording and analysis play a crucial role. The system saves detailed parameters and corresponding simulation results for each correction, forming a complete historical record. This data can not only be used to track optimization progress but also provide a reference for parameter adjustments in similar projects. By analyzing this historical data, optimization strategies for different harness types and assembly scenarios can be summarized, accumulating experience for future projects.

[0091] The final optimized parameters need to undergo comprehensive verification to ensure stable performance under various operating conditions. The verification process includes boundary condition testing and extreme condition simulation to confirm that the optimized parameters effectively prevent torque over-limit phenomena under different conditions. Through this systematic optimization process, the timing parameters of the wire crimping equipment are finely adjusted, providing technical assurance for the stability and reliability of the wire harness assembly process.

[0092] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0093] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automated assembly method for automotive wiring harnesses, characterized in that, include: A wiring harness path model is constructed based on the electrical architecture topology of the target vehicle model. The wiring harness path model includes a sequence of branch point coordinates and bending radius constraints. Construct a tooling equipment model, which is used to simulate the action sequence of the wire clamp installation robot and the wire crimping equipment during the wire harness assembly process; Based on the selected assembly condition parameters, a spatial coupling simulation is performed on the tooling equipment model and the wire harness path model to generate an assembly trajectory sequence. Based on the interference detection results of the assembly trajectory sequence, determine whether there is an interference risk in the current assembly scheme; Determining whether there is an interference risk in the current assembly scheme includes: when the assembly trajectory sequence meets a first preset condition or a second preset condition, determining that there is an interference risk; The first preset condition is that the number of times the instantaneous value of the bending radius of the wire harness path model in the spatial coupling simulation is less than the minimum bending radius of the material exceeds a set threshold; the second preset condition is that the spatial distance between the wire harness branch path segment and the adjacent sheet metal part is lower than the safety gap for two consecutive simulation cycles.

2. The automatic assembly method based on automotive wiring harnesses according to claim 1, characterized in that, When the electrical architecture topology includes engine compartment wiring harness branches, dashboard wiring harness branches, and door wiring harness branches, the wiring harness path model constructed based on the electrical architecture topology of the target vehicle model includes: Based on the electrical architecture topology, a set of three-dimensional coordinates is generated for the engine compartment branch path segment, the instrument panel branch path segment, and the door branch path segment. The engine compartment branch path segment is connected to the main trunk segment of the main wiring harness path model through transition surface constraints, the dashboard branch path segment is connected to the main trunk segment through rigid fixed point constraints, and the door branch path segment is connected to the main trunk segment through flexible swing constraints to construct and obtain the wiring harness path model.

3. The automatic assembly method based on automotive wiring harnesses according to claim 2, characterized in that, The step of performing spatial coupling simulation of the tooling equipment model and the wiring harness path model based on the selected assembly condition parameters includes: Based on the selected wire diameter parameters, the pressure command is output through the wire tension control strategy model to control the crimping torque of the wire crimping device in the tooling equipment model; When the wire crimping device reaches the preset torque threshold, the displacement command is output by the branch positioning strategy model to control the position offset of the branch point in the wire harness path model, so as to realize the motion coordination between the path model and the device model.

4. The automatic assembly method based on automotive wiring harnesses according to claim 2, characterized in that, Prior to the spatial coupling simulation, the following is also included: The displacement signal with a step change is input to the path correction port of the branch positioning strategy model to calibrate the branch path smoothness control parameters. When the rate of change of curvature of the branch path meets the preset smoothness requirement, the step-change pressure signal is input to the tension port of the conductor tension control strategy model to calibrate the conductor deformation compensation parameters. When the deviation between the conductor deformation compensation parameters and the physical test data is less than the allowable tolerance, a tooling equipment model capable of performing coupled simulation is obtained.

5. The automatic assembly method based on automotive wiring harnesses according to claim 1, characterized in that, Also includes: When there is a risk of interference, optimize the timing parameters of the wire crimping equipment in the tooling equipment model; Based on the optimized action timing parameters, the spatial coupling simulation is re-executed until the interference detection result of the assembly trajectory sequence does not meet the first preset condition and the second preset condition.

6. The automatic assembly method based on automotive wiring harnesses according to claim 2, characterized in that, Construct the engine compartment branch path segment, including: Based on the distribution of high-temperature areas in the engine compartment, the wiring harness branches in the engine compartment are discretized into heat-resistant material sections and non-heat-resistant material sections. The heat-resistant material section and the non-heat-resistant material section are connected by a thermal expansion compensation algorithm, and temperature gradient change parameters are set.

7. The automatic assembly method based on automotive wiring harnesses according to claim 2, characterized in that, Construct the dashboard branch path segment, including: Using the mounting holes inside the instrument panel as reference points, the instrument panel wiring harness branches are divided into rigid fixed sections and movable allowance sections. The spatial coordinates of the rigid fixed section are locked to the vehicle body coordinate system, and the movable margin section is connected to the rigid fixed section through an elastic deformation algorithm.

8. The automatic assembly method based on automotive wiring harnesses according to claim 5, characterized in that, Optimize the timing parameters of the wire crimping equipment, including: Extract the time sequence in which the wire crimping torque exceeds the material yield strength in the spatial coupling simulation; Based on the branch point displacement data corresponding to the time sequence, the slope of the pressure rise curve of the wire crimping device is reversed.

9. An automated assembly system for automotive wiring harnesses, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the automatic assembly method based on automotive wiring harness as described in any one of claims 1 to 8.

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