Airplane wire harness three-dimensional wiring path automatic search design method

Abstract

The invention discloses an aircraft wire harness three-dimensional wiring path automatic search design method. An aircraft electrical line interconnection system (EWIS) is very complex, the cable laying space is narrow, the laying path is complex, and the design period is long. In order to automatically and quickly perform three-dimensional wiring design, the method provided by the invention comprises the following steps: processing a cable laying channel network as a graph of a complex network, storing channel network data in two data forms of three-dimensional space geometric data and graph edge list data, and converting the edge list data into an adjacent matrix form, and automatically searching the shortest path network for cable laying by using the adjacent matrix. And generating a three-dimensional mathematical model of cable laying according to the shortest path network and the corresponding channel network three-dimensional space position information data. The method is simple in data structure, convenient to maintain and reuse, high in calculation speed and high in search efficiency, design optimization can be carried out through rapid iteration, the weight of the EWIS system is minimized, and the design period is greatly shortened.

Description

Technical Field

[0001] The invention relates to an aircraft electrical wiring interconnection system (EWIS), and in particular to an automatic search and design method for a three-dimensional wiring path of an aircraft wiring harness. Background Art

[0002] The electrical wiring interconnection system (EWIS) of an aircraft is likened to the blood vessels and nervous system of an aircraft. Cables with up to 100-400 kilometers and 30,000-50,000 connection points are buried on the ceiling, behind the wall panels, and under the floor of the aircraft, connecting all the systems of the aircraft and transmitting data, signals, and electrical energy. The increasing complexity and integration of aircraft have made the cable laying space small and the cable laying paths complicated, which has brought many challenges to the design, manufacture, certification, and rapid market launch of new products. The design cycle of aircraft wiring harnesses may be as long as several years. With the widespread use of digital design technology, the current design cycle is still quite long, and there are still problems such as cumbersome design, low efficiency, low automation level, and high error rate.

[0003] In order to solve the above problems, reduce manual workload, and automate and quickly perform EWIS wiring design, the present invention proposes an automatic search and design method for aircraft wiring harness three-dimensional wiring paths based on complex network graph calculation. Summary of the invention

[0004] Purpose of the invention: In order to automatically and quickly perform EWIS wiring design and greatly shorten the design and development cycle of the aircraft EWIS system, the present invention proposes an automatic search and design method for aircraft wire harness three-dimensional wiring paths.

[0005] Technical solution: The aircraft EWIS system network is processed and calculated as a complex network graph, and the graph algorithm is used to automatically search for the shortest path as the wiring harness laying path. The main steps include: (1) Extract channel network data: Extract the data of the channels inside the aircraft that can be used to lay cables, and simplify the channels into a channel network consisting of a series of points and edges. Points represent nodes that cables can pass through, and edges represent paths that cables can pass through. Cables cannot be laid between nodes without edge connections. The channel network is processed and calculated as a graph. In order to reduce the number of nodes in the network and reduce the complexity of the graph algorithm path search, only the information of key nodes and edges is saved in the channel network. Key nodes are defined as the two endpoints of the channel and the set of nodes that can have branches in the middle. The edge connecting two nodes is defined as a generalized edge, which can be a straight line segment, a three-dimensional space polyline, a three-dimensional space curve, or a combination of them. The three-dimensional channel network data is saved in two data forms: three-dimensional space geometry data and graph edge list data. The correct mapping relationship needs to be maintained between the two data forms. The three-dimensional space geometry data saves the detailed three-dimensional space geometry information of the channel network. The edge list data can be a dictionary data type or a data table format. The edge list saves the edge and node numbers and attributes. The attributes can include length, maximum diameter, maximum weight, etc. Convert the edge list to an adjacency matrix for the application of graph algorithms. The adjacency matrix contains information about nodes and path lengths. The edge list is more intuitive and easier to understand and maintain, while the adjacency matrix is ​​required for the analysis and calculation of the graph. The adjacency matrix does not need to contain detailed three-dimensional spatial information of the channel path; (2) Automatic search for the shortest path: Add the starting and ending location information of the cable (that is, the location information of the terminal blocks of the equipment or load) and their distances from the available channel network nodes and the data of the cable attributes (diameter, weight per unit length, etc.) to the edge list and adjacency matrix of the channel network graph. Use the adjacency matrix to automatically search for the shortest path from the starting point to the end point. Graph calculation can be used to search for the shortest path of the global layout path of all cables or harnesses, or to search for the shortest path of a pair of starting and ending points. All the starting and ending points and the shortest path information can generate a new graph, which represents the shortest path network for cable laying. Analyze the shortest path network graph to check the rationality of the cable laying path. For example, if the search results show that there are too many cables passing through a channel, it may lead to the inability to pass these cables due to channel space limitations when actually laying the cables, or the cable weight may exceed the maximum weight allowed by the channel. If these problems are found, constraints can be added, or the adjacency matrix can be modified to exclude (or select) some nodes and channels for re-search; (3) Generate EWIS three-dimensional network: Generate the EWIS cable laying network based on the automatically searched shortest path and the corresponding three-dimensional spatial geometric information of the path. The cable laying network generated in this step is a three-dimensional spatial network composed of nodes and lines. It is not a three-dimensional digital model and does not contain the cable diameter information; (4) Generate EWIS 3D digital model: Generate EWIS 3D digital model based on the EWIS cable laying network data according to the diameter information of the cable or wire harness; (5) Local adjustment and optimization: Place the generated EWIS three-dimensional digital model into the three-dimensional digital model of the aircraft cable laying channel, check the EWIS digital model, and adjust and optimize the local digital model to meet the design requirements. For example, the three-dimensional digital model contains the diameter information of the cable or harness. It is necessary to check whether the channel space is sufficient to pass the cable or harness to be laid, whether the cable or harness will interfere with the surrounding digital models, whether the minimum gap meets the design requirements, whether the minimum bending radius meets the design requirements, whether the weight distribution is balanced in the overall layout, and whether the cables with large diameter (that is, heavy weight) are prioritized on the shortest path. If it is necessary to redesign the path of some cables, return to step (2) and search again under the constraints.

[0006] Beneficial effects: (1) The aircraft EWIS wiring design method proposed in the present invention uses graph computing programming to realize automated search, with high search efficiency and short calculation time, which can greatly shorten the aircraft EWIS system design cycle; (2) The method proposed in the present invention is simple and efficient, with clear and intuitive process steps and simple implementation, which can be realized by programming using open source development tools; (3) The storage format of the cable laying channel network data is streamlined and practical, which is convenient for maintenance and reuse; (4) Under the constraint of giving priority to ensuring that heavy cables are on the shortest path, the weight of the EWIS system can be minimized; (5) This method has high calculation efficiency and can perform rapid search and iteration of the cable laying network to perform optimization design. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 It is a flow chart of the method of the present invention.

[0008] Figure 2 It is a schematic diagram of the application of the method of the present invention. DETAILED DESCRIPTION

[0009] The technical solution of the present invention is further described below in conjunction with an embodiment. The present embodiment describes an automatic search and design method for a three-dimensional wiring path of an aircraft wiring harness, comprising the steps of: (1) Extracting channel network data: If there is no reusable channel data, it is necessary to extract the digital model and centerline data of the channel in the CAD system and simplify the channel into a channel network consisting of a series of points and edges. Points represent nodes that cables can pass through, and edges represent paths that cables can pass through. Cables cannot be laid between nodes without edge connections. The channel network is processed and calculated as a graph. In order to reduce the number of nodes in the network and reduce the complexity of the graph algorithm path search, only the information of key nodes and edges is saved in the channel network. Key nodes are defined as the set of two endpoints of the channel and the nodes in the middle that can have branches. The edge connecting two nodes is defined as a generalized edge, which can be a straight line segment, a three-dimensional space polyline, a three-dimensional space curve, or a combination of them. The three-dimensional channel network data is saved in two data forms: three-dimensional space geometry data and graph edge list data. The correct mapping relationship needs to be maintained between the two data forms. The three-dimensional space geometry data saves the detailed three-dimensional space geometry information of the channel network. It can be saved in the format of the CAD system or in the form of three-dimensional coordinate data of a spatial point set. The three-dimensional space geometry of the channel network can be regenerated based on the three-dimensional coordinate data of the point set. The edge list data can be in the form of a dictionary data type or a data table (such as a CSV data table). The two data forms are equivalent and can be converted to each other. The edge list stores the numbers and attributes of the edges and nodes. The attributes may include length, maximum diameter, maximum weight, etc. The edge list is converted to an adjacency matrix for calculation by applying graph algorithms. The adjacency matrix contains information about nodes and path lengths. (2) Automatic search for the shortest path: Calculate the distance from the available channel network nodes based on the coordinate position information of the airborne equipment terminal block, and add the new node and edge information as well as the cable attribute (diameter, weight per unit length, etc.) data to the edge list of the channel network graph, and update the adjacency matrix. Use the adjacency matrix to automatically search for the shortest path from the start point to the end point. All the start points, end points and shortest path information can generate a new graph, which represents the shortest path network for cable laying. Analyze the shortest path network graph to check the rationality of the cable laying path. For example, if the search results show that there are too many cables passing through a channel, it may lead to the inability to pass these cables due to channel space limitations during actual cable laying, or the cable weight may exceed the maximum weight allowed by the channel. If these problems are found, constraints can be added, or the adjacency matrix can be modified to exclude (or select) some nodes and channels for re-search; (3) Generate EWIS 3D network: Generate the EWIS cable laying network in the CAD system based on the automatically searched shortest path and the corresponding 3D spatial geometric information of the path. The cable laying network generated in this step is a 3D spatial network composed of nodes and lines. It is not a 3D digital model and does not contain the cable diameter information. (4) Generate EWIS 3D digital model: Generate EWIS 3D digital model in CAD system based on the diameter information of cable or wire harness and network data of EWIS cable laying; (5) Local adjustment and optimization: The generated EWIS 3D digital model and the aircraft cable laying channel 3D digital model are compared and analyzed in the CAD system, the EWIS digital model is checked, and the local digital model is adjusted and optimized to meet the design requirements. For example, the 3D digital model contains the diameter information of the cable or harness. It is necessary to check whether the channel space is sufficient to pass the cable or harness to be laid, whether the cable or harness will interfere with the surrounding digital models, whether the minimum gap meets the design requirements, whether the minimum bending radius meets the design requirements, whether the weight distribution is balanced in the overall layout, and whether the cables with large diameter (that is, heavy weight) are prioritized on the shortest path. If it is necessary to redesign the path of some cables, return to step (2) and search again under the constraints.

[0010] The above-described embodiment is only a specific implementation example of the present invention, and is not intended to limit the scope of implementation of the present invention. All changes made based on the principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for automatically searching and designing a three-dimensional wiring path for an aircraft wiring harness, characterized in that: Includes steps: (1) Extract EWIS wiring channel network data and represent the channel network in the form of a graph so that it can be processed and calculated using graph calculation methods; (2) Automatically search for the shortest path for cable laying using graph calculation methods; (3) Generate a three-dimensional network for EWIS cable laying based on the searched shortest path; (4) Generate EWIS 3D digital model based on the 3D network data of EWIS cable laying; (5) Locally adjust and optimize the EWIS 3D digital model to meet the design requirements.

2. The method for automatically searching and designing the three-dimensional wiring path of an aircraft wiring harness according to claim 1, characterized in that: In the step (1), only the information of key nodes and edges is saved in the graph of the channel network, wherein the key nodes are defined as the two end points of the channel and the set of nodes in the middle that may have branches, wherein the edge connecting two nodes is defined as a generalized edge, and the generalized edge may be a straight line segment, a three-dimensional space polyline, a three-dimensional space curve, or a combination thereof.

3. The method for automatically searching and designing the three-dimensional wiring path of an aircraft wiring harness according to claim 1, characterized in that: In the step (1), the three-dimensional channel network data is saved in two data forms: three-dimensional spatial geometric data and graph edge list data. A correct mapping relationship needs to be maintained between the two data forms so that a three-dimensional spatial network of cable laying paths can be generated based on the shortest path searched by graph calculation.

4. The method for automatically searching and designing a three-dimensional wiring path of an aircraft wiring harness according to claim 1, characterized in that: In the step (2), the starting and ending position information of the cable and the data of the cable attributes (diameter, weight per unit length, etc.) are added to the edge list and adjacency matrix of the channel network graph, and the adjacency matrix is ​​used to automatically search for the shortest path from the starting point to the end point.

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