Method and system for positioning shield termination splices

Abstract

A method and data processing system for automatically determining positions of shield termination splices in a wire harness are provided. The method comprises the steps of accessing a digital representation of the wire harness, accessing a predefined set of constraints where each constrain defines a repositioning rule for repositioning the one or more splices and simulating the positioning of the one or more splices at different positions in the wire harness, to identify positions for each splice that are compatible with the set of constraints.

Description

METHOD AND SYSTEM FOR POSITIONING SHIELD TERMINATION SPLICESTECHNICAL FIELD

[0001] The present disclosure relates to methods and systems for wire harness design, and, in particular, for positioning shield termination splices in a wire harness.BACKGROUND

[0002] Wire harnesses are widely used in systems such as vehicles, electrical devices, machinery, and other systems to secure and organize electric cabling. Wire harness may include components such as electrical connectors, terminals, splices, shielding and mounting brackets. Wire harnesses improve safety by reducing the risk of shorting and protecting cabling against adverse effects such as heat, moisture, vibrations, and abrasion. Wire harnesses also help to optimize use of space and simplify installation and maintenance.

[0003] Wire harness design combines different aspects of engineering including electrical system design, cable design, electrical, thermal, and mechanical analysis, testing and validation, and manufacturing. The degree of freedom of the design may be limited by constraints. In some cases, these constraints may be physical or structural constraints relating to positioning of components in relation to other components in the wire harness. In other cases, constraints may relate to features of the system or environment where the wire harness is deployed. For example, components in an engine of a vehicle may heat up during operation, preventing cabling being routed in the vicinity of those components.

[0004] Splices are points in a wire harness where multiple wires connect to each other. Shield termination splices are splices that are used to electrically connect the shield of a shielded multicore cable to a ground point. Identification of the position of shield termination splices may be performed manually, wherein the designer identifies the termination point for each shield by analyzing the electrical connectivity. Once the position of the termination point has been identified, the related shield termination splice is moved as close as possible to the termination point on the connector. While this method is sufficient for simple harness designs, in complex systems, such as cars and aircraft, wire harness designs may contain hundreds of shield termination points. For these designs, manual positioning of shield termination splices is a potentially time consuming and challenging task.

[0005] In order to simplify the design process, aspects of wire harness design may be digitalized using Computer Aided Design (CAD). CAD applications are powerful software applications that enable designers to create, manipulate, and visualize objects through a user interface. CAD applications may integrate with other applications including simulation software, computer aided manufacturing (CAM) and engineering (CAE) applications, and product lifecycle management (PLM) applications.

[0006] A wire harness design tool in a CAD application may combine different sources of data including data from electronic CAD (ECAD) tools and mechanical CAD (MCAD) tools. ECAD tools are used to design and create electronic structures. An ECAD design may include the wiring layout and electrical connectivity data for a wire harness. MCAD tools are used to create mechanical structures. MCAD may be used to design a wire harness topology in a three-dimensional environment.

[0007] In the context of splice positioning, the splices are initially objects represented in ECAD data. However, the positions of the splices are defined with respect to a wire bundle, an object that only exists in an MCAD representation. During the design process, when data from ECAD and MCAD tools are brought together, the wire harness design tool is the first point in this type of development flow at which both objects, splices, and bundles, are brought together in the harness design. However, at this point, none of the ECAD splices have valid positions on any of the MCAD bundles. Consequently, all splices are located in free space in the diagram space and the design engineer still has to manually position the splices. This is time consuming and reduces the possible benefit from digitizing the wire harness design process.SUMMARY

[0008] According to a first aspect, a computer implemented method for automatically determining positions for one or more shield termination splices in a wire harness is provided. The method comprises: accessing a digital representation of the wire harness; accessing a predefined set of constraints, wherein each constraint defines a repositioning rule for repositioning the one or more splices; and simulating the positioning of the one or more splices at different positions in the wire harness, to identify positions for each splice that are compatible with the set of constraints.

[0009] The method according to the first aspect improves wire harness design processes by automating the positioning of shield termination splices. This improves the efficiency and quality of wire harness design and manufacture and reduces errors in complex wire harness designs.

[0010] In a first implementation form, the method according to the first aspect simulating the positioning of the one or more splices comprises determining an initial position for each splice relative to an associated target object, based on a first subset of constraints in the set of constraints.

[0011] In a second implementation form, a constraint in the first subset identifies splices that are eligible for repositioning.

[0012] In a third implementation form, a constraint in the first subset identifies a target object relative to which a splice may be positioned.

[0013] In a fourth implementation form, a constraint in the first subset specifies a minimum distance between a splice and an associated target object.

[0014] In a fifth implementation form, simulating the positioning of the one or more splices further comprises simulating, for each splice, the repositioning of the splice, based on a second subset of constraints in the set of constraints, different from the first subset.

[0015] In a sixth implementation form, a constraint in the second subset specifies a minimum distance between a splice and one or more objects in the wire harness, different from the associated target object.

[0016] In a seventh implementation form, the method comprises determining whether a position is a valid position based on a third subset of constraints in the set of constraints, different from the first subset and the second subset.

[0017] In an eighth implementation form, a constraint in the third subset of constraints specifies a region of the wire harness where a splice is prohibited from being placed.

[0018] In a ninth implementation form, when more than one position is identified for at least one of the splices, the method comprises applying at least one criterion to the identified positions to select a single position for each splice.

[0019] In a tenth implementation form, the at least one criterion is a criterion relating to a distance to a target object, a number of wire crossings in the wire harness, or an amount of activity on the path between a splice and a target object.

[0020] These and other aspects of the disclosure are apparent from the embodiments described below.BRIEF DESCRIPTION OF THE DRAWINGS

[0021] For a more complete understanding of the present disclosure, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

[0022] Figure 1 shows a schematic diagram of shield termination splice, according to an example.

[0023] Figure 2 shows a flow diagram of a method for automatically determining positions for shield termination splices in a wire harness, according to an example.

[0024] Figure 3 is a flow diagram of a method for simulating the positioning of shield termination in a wire harness, according to an example.

[0025] Figure 4 illustrates an example of a data processing system in which embodiments of the present disclosure may be implemented.DETAILED DESCRIPTION

[0026] Example embodiments are described below in sufficient detail to enable those of ordinary skill in the art to embody and implement the systems and processes herein described. It is important to understand that embodiments can be provided in many alternate forms and should not be construed as limited to the examples set forth herein.

[0027] Accordingly, while embodiments can be modified in various ways and take on various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. There is no intent to limit to the particular forms disclosed. On the contrary, all modifications, equivalents, and alternatives falling within the scope of the appended claims should be included. Elements of the example embodiments are consistently denoted by the same reference numerals throughout the drawings and detailed description where appropriate.

[0028] The terminology used herein to describe embodiments is not intended to limit the scope. The articles “a,” “an,” and “the” are singular in that they have a single referent, however the use of the singular form in the present document should not preclude the presence of more than one referent. In other words, elements referred to in the singular cannumber one or more, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes,” and / or “including,” when used herein, specify the presence of stated features, items, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, items, steps, operations, elements, components, and / or groups thereof.

[0029] Unless otherwise defined, all terms including technical and scientific terms used herein are to be interpreted as is customary in the art. It will be further understood that terms in common usage should also be interpreted as is customary in the relevant art and not in an idealized or overly formal sense unless expressly so defined herein.

[0030] Figure 1 is a schematic diagram 100 of a shield termination splice in a wire harness, according to an example. In the diagram 100, a shielded multicore cable 110 is connected to a connector 120. The cable 110 forms part of a bundle of cables 130 in the wire harness. The cable 110 comprises conducting wires 140, surrounded by a shield 150 and outer insulation 160. The conducting wires 140 may be made from any suitable conducting material such as copper. The shield 150 may be formed from braided metal or metal foil. The connector 120 may be any kind of connector found in a wire harness. Connectors may vary in terms of shape, size, material, and dimension. Examples of connector types found in wire harnesses include circular, pin, blade, and modular connectors.

[0031] The shield 150 reduces electromagnetic interference (EMI) caused by electrical currents in conducting wires 140 and other nearby wires and provides improved signal integrity. Near the connector 120, the shield 150 is exposed by stripping back the outer insulation 160. A shield termination splice 170, connects a drain wire 180 with the shield 150. The drain wire 180 is unprotected conducting wire which carries unwanted electrical noise away from the shield 150 to ground.

[0032] In order to provide effective shielding up to the connector 120, the shield termination splice 170 is positioned as close to the connector 120 as possible. In the example of Figure 1, a single shield terminates at the connector. In cases where multiple shields terminate to the same connector, the wire harness designer must decide where to place shield termination splices for each shield at positions along the bundle. Manually positioning shield termination splices is a time consuming and error prone task.

[0033] The methods and systems described herein automatically determine positions for shield termination splices in a wire harness. According to examples of the method,termination points are programmatically identified based on electrical connectivity data. The repositioning of shield termination splices that terminate at a termination point is simulated, subject to a set of constraints.

[0034] Figure 2 is a flow chart showing a method 200, for automatically determining positions for one or more shield termination splices in a wire harness. The method 200 may be used in conjunction with other methods and systems described herein. In particular, the method 200 may be implemented in a wire harness design tool in a computer-aided design (CAD) system. The wire harness design tool may facilitate the creation, modification, and analysis of a wire harness design in a CAD system, through a user interface, provided through a display on a computing device. A user may interact with the user interface through the use of one or more input devices connected to the computing device.

[0035] At block 210, a digital representation of a wire harness is accessed. According to an example, the digital representation of the wire harness may include a wiring layout and electrical connectivity information, obtained from ECAD data. This data may comprise a representation of the one or more splices. The digital representation may also include MCAD data comprising a three-dimensional representation of the wire harness topology. When using the wire harness design tool in CAD, the digital representation may be represented visually in the user interface of the CAD application.

[0036] At block 220, a predefined set of constraints is accessed. Each constraint defines a repositioning rule for repositioning the one or more splices. The set of constraints may include user-defined constraints and hard-coded constraints. In some cases, the user-defined constraints may be placed in three categories: primary constraints that specify which splices may be moved, which target objects the splices should be moved relative to, and how far at a minimum from those target objects the splices may be placed, secondary constraints that specify further positioning information such as the minimum distance allowable between splices and other components present in the harness, and exclusion constraints that specify regions of the harness where splices cannot be placed. In some examples, user-defined constraints may be modifiable through a user-interface tool.

[0037] The hardcoded constraints may include constraints to ensure that any resulting configuration of splices is correct, by construction. For example, a first hardcoded constraint may specify that a splice can only be positioned on the path of a multicore cable it is connected to. A second hardcoded constraint may specify that splices are positioned in anoptimal order, so that no wires need to cross over a splice. In other examples, there may be additional hardcoded constraints.

[0038] At block 230, the positioning of the one or more splices is simulated at different positions in the wire harness, to identify positions for each splice that are compatible with the set of constraints.

[0039] Figure 3 is a flow chart showing a method 300, for simulating the positioning of one or more splices at different positions in a wire harness. The method 300 may be used in conjunction with methods and systems described herein. In particular, the method 300 may be used to implement block 230 of the method 200.

[0040] At block 310, an initial position for each splice is determined, relative to an associated target object, based on a first subset of constraints in the set of constraints. According to examples, the first subset may be the subset of primary constraints that specify which splices may be moved, which target objects the splices should be moved relative to, and how far at a minimum from those target objects the splices may be placed. In an example, for each splice, the method meanders away from the target object until all positions at the required distance from that object are found, according to the subset of constraints. Due to the branching nature of wire harnesses, there may be multiple possible positions at this stage.

[0041] At block 320, any invalid positions from the previous step are removed. According to examples, invalid positions are positions which violate any of the hard-coded constraints or exclusion constraints such as such as positions on prohibited bundles, or positions that are not on the path of the connected multicore cable.

[0042] At block 330, for each splice, repositioning of the splice is simulated, based on a second subset of constraints in the set of constraints, different from the first subset. According to examples, the second subset of constraints comprises the secondary constraints that specify further positioning information such as the minimum distance allowable between splices and other components in the harness. Simulating repositioning based on the secondary constraints ensures that splices are not moved too close to other existing components. The secondary constraints are applied for each valid position for each splice. If any of the secondary constraints are violated, then method repositions the splice by meandering away from the target object, until a position is found that does not violate any of the constraints. Performing the meandering away from the target object ensures that the primary constraintsare still honored, since the primary constraint defines the minimum distance to the target object.

[0043] Blocks 320 and 330 may be repeated until only valid positions are remaining, with no constraints being violated. In the case where a splice has more than one valid position, criteria may be applied to select a single position for the splice. In examples described herein, the criteria may relate to a distance to a target object, a number of wire crossings in the wire harness, or an amount of activity on the path between a splice and a target object. This ensures that the final output of the method is a single valid position for each splice, which has been determined in an automated fashion.

[0044] The data obtained from the simulation for positioning the termination splices may be used in the manufacturing of the wire harness. In some cases, the data obtained from the simulation may be exported to one or more automated manufacturing devices such as automated cable cutting machines and automated crimpling machines, to facilitate the manufacturing of a wire harness design. Data obtained from the simulation may also be used to generate technical documentation and assembly instructions for the wire harness design. The integration of the methods described herein optimizes the manufacturing of complex wire harness designs.

[0045] Figure 4 illustrates an example of a data processing system in which an embodiment of the present disclosure may be implemented, for example, a CAD application configured to perform the methods of the embodiments of the present disclosure as described herein. The data processing system 400 comprises a processor 410 connected to a local system bus 420. The local system bus connects the processor to a main memory 430 and graphics display adaptor 440, which may be connected to a display 450. The data processing system may communicate with other systems via a wireless user interface adapter connected to the local system bus 420, or via a wired network, for example, to a local area network. Additional memory 460 may also be connected via the local system bus 420.

[0046] A suitable adaptor, such as wireless user interface adapter 470, for other peripheral devices, such as a keyboard 480 and mouse 490, or other pointing device, allows the user to provide input to the data processing system. Other peripheral devices may include one or more I / O controllers such as USB controllers, Bluetooth controllers, and / or dedicated audio controllers (connected to speakers and / or microphones). Various peripherals may be connected to the USB controller (via various USB ports) including input devices (e.g.,keyboard, mouse, touch screen, trackball, camera, microphone, scanners), output devices (e.g., printers, speakers), or any other type of device that is operative to provide inputs or receive outputs from the data processing system.

[0047] Further, devices referred to as input devices or output devices may both provide inputs and receive outputs of communications with the data processing system. Further, other peripheral hardware connected to the I / O controllers may include any type of device, machine, or component that is configured to communicate with a data processing system.

[0048] An operating system included in the data processing system enables an output from the system to be displayed to the user on the display and the user to interact with the system. Examples of operating systems that may be used in a data processing system may include Microsoft Windows™, Linux™, UNIX™, iOS™, and Android™ operating systems.

[0049] In addition, the data processing system 400 may be implemented as in a networked environment, distributed system environment, virtual machines in a virtual machine architecture, and / or cloud environment. For example, the processor and associated components may correspond to a virtual machine executing in a virtual machine environment of one or more servers. Examples of virtual machine architectures include VMware ESCi, Microsoft Hyper- V, Xen, and KVM.

[0050] Those of ordinary skill in the art will appreciate that the hardware depicted for the data processing system 400 may vary for particular implementations. For example, the data processing system 400 in this example may correspond to a computer, workstation, and / or a server. However, it should be appreciated that alternative embodiments of a data processing system may be configured with corresponding or alternative components such as in the form of a mobile phone, tablet, controller board or any other system that is operative to process data and carry out functionality and features described herein associated with the operation of a data processing system, computer, processor, and / or a controller discussed herein. The depicted example is provided for the purpose of explanation only and is not meant to imply architectural limitations with respect to the present disclosure.

[0051] The data processing system 400 may be connected to the network (not a part of data processing system 400), which can be any public or private data processing system network or combination of networks, as known to those of skill in the art, including the Internet. The data processing system 400 can communicate over the network with one or more other data processing systems such as a server (also not part of the data processingsystem 400). However, an alternative data processing system may correspond to a plurality of data processing systems implemented as part of a distributed system in which processors associated with several data processing systems may be in communication by way of one or more network connections and may collectively perform tasks described as being performed by a single data processing system. Thus, it is to be understood that when referring to a data processing system, such a system may be implemented across several data processing systems organized in a distributed system in communication with each other via a network.

[0052] The data processing system 400 is adapted to carry out the methods in accordance with the embodiments described herein. For example, the keyboard 480 and mouse 490 may function as a user input device for receiving information from the user, the processor 410 may be adapted to carry out the steps of the method and the display 450 adapted to display a particular view to the user. A computer product comprising instructions which, when run on a computer, such as the data processing system 400, may be provided to cause the computer to execute the steps of the methods of the embodiments of the present disclosure outlined herein.

[0053] The present disclosure is described with reference to flow charts and / or block diagrams of the method, devices, and systems according to examples of the present disclosure. Although the flow diagrams described above show a specific order of execution, the order of execution may differ from that which is depicted. Blocks described in relation to one flow chart may be combined with those of another flow chart. In some examples, some blocks of the flow diagrams may not be necessary and / or additional blocks may be added.

[0054] The present disclosure can be embodied in other specific apparatus and / or methods. The described embodiments are to be considered in all respects as illustrative and not restrictive. In particular, the scope of the disclosure is indicated by the appended claims rather than by the description and figures herein. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

CLAIMS1. A computer-implemented method for automatically determining positions for one or more shield termination splices in a wire harness, the method comprising: accessing a digital representation of the wire harness; accessing a predefined set of constraints, wherein each constraint of the predefined set of constraints defines a repositioning rule for repositioning the one or more shield termination splices; and simulating a positioning of the one or more shield termination splices at different positions in the wire harness, to identify positions for each splice of the one or more shield termination splices that are compatible with the predefined set of constraints.

2. The computer-implemented method of claim 1, wherein the simulating of the positioning of the one or more shield termination splices comprises: determining an initial position for each splice relative to an associated target object, based on a first subset of constraints in the predefined set of constraints.

3. The computer-implemented method of claim 2, wherein a constraint in the first subset of constraints identifies splices that are eligible for repositioning.

4. The computer-implemented method of claim 2, wherein a constraint in the first subset of constraints identifies a target object relative to which a splice may be positioned.

5. The computer-implemented method of claim 2, wherein a constraint in the first subset of constraints specifies a minimum distance between a splice and the associated target object.

6. The computer-implemented method of claim 2, wherein the simulating of the positioning of the one or more shield termination splices further comprises: simulating, for each splice of the one or more shield termination splices, the repositioning of the splice, based on a second subset of constraints in the predefined set of constraints,wherein the second subset of constraints is different from the first subset of constraints.

7. The computer-implemented method of claim 6, wherein a constraint in the second subset of constraints specifies a minimum distance between a splice and one or more objects in the wire harness, different from the associated target object.

8. The computer-implemented method of claim 6, further comprising: determining whether a position is a valid position based on a third subset of constraints in the set of constraints, wherein the third subset of constraints is different from the first subset of constraints and the second subset of constraints.

9. The computer-implemented method of claim 8, wherein a constraint in the third subset of constraints specifies a region of the wire harness where a splice is prohibited from being placed.

10. The computer-implemented method of claim 1, wherein, when more than one position is identified for at least one of the shield termination splices, the method comprises: applying at least one criterion to the identified positions to select a single position for each splice.

11. The computer-implemented method of claim 10, wherein the at least one criterion is a criterion relating to a distance to a target object, a number of wire crossings in the wire harness, or an amount of activity on a path between a splice and the target object.

12. A computer-readable medium comprising instructions that, when executed by a computer, cause the computer to carry out the method according to any one of claims 1 to13. A data processing system comprising: a processor; and a memory storing instructions that, when executed by the processor cause the processor to execute the method according to any one of claims 1 to 11.

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