A routing test system

Abstract

The application discloses a routing test system, which is characterized by being used for testing a multi-bus electronic control unit (ECU), each CAN bus comprising a first bit signal line and a second bit signal line, M being an integer, and the test system comprising: a test device, each communication channel comprising a first bit signal communication channel and a second bit signal communication channel; a channel gating module comprising two groups of sub-gating modules, each group of sub-gating modules being electrically connected between a target bit signal communication channel of the test device and each target bit signal line of the ECU; the target bit signal communication channel being the first bit signal channel or the second bit signal channel; the target bit signal line being the first bit signal line or the second bit signal line; and the channel gating module comprising a control signal input end, which receives an external control instruction to change a physical connection channel between part of the target bit signal lines of the ECU and part of the target bit signal communication channels of the test device. According to the embodiment of the application, the efficiency of routing test is improved.

Description

Technical Field

[0001] This application belongs to the field of automotive electronics testing, and in particular relates to a routing testing system. Background Technology

[0002] In automotive electronics, industrial control, and other fields, Electronic Control Units (ECUs), as core control components, typically integrate multiple heterogeneous communication buses (such as CAN, LIN, Ethernet, etc.) to achieve information exchange with various sensors, actuators, and other control units. As ECU functions become increasingly complex, the number of integrated buses continues to rise. Testing the communication functions of multi-bus ECUs (such as message transmission, routing logic verification, and fault response) has become a critical step in ensuring equipment reliability. During testing, communication links must be established between the multiple buses of the ECU and the physical channels of the test equipment (such as CANOE), and functional verification is achieved through signal acquisition and analysis.

[0003] Currently, in message routing testing of multi-bus ECUs, the industry commonly uses CANOE devices as the primary testing tool. The testing process relies on manual operation; testers manually select the target bus of the ECU and physically connect it to the hardware channel of the CANOE according to the specific test case. Since the number of CANOE hardware channels is limited (usually supporting a maximum of 4 buses connected at the same time), it is necessary to switch buses by repeatedly plugging and unplugging cables to achieve test coverage of all buses.

[0004] The contradiction between the limited number of test equipment channels and the demand for multi-bus testing is prominent. Parallel testing of multiple buses cannot be achieved, and frequent switching can easily cause damage to the equipment interface due to operational errors, increasing testing costs. Summary of the Invention

[0005] This application provides a routing test system that can improve testing efficiency.

[0006] On one hand, embodiments of this application provide a routing test system for testing multi-bus electronic control units (ECUs). Each ECU includes M CAN buses, and each CAN bus includes a first signal line and a second signal line, where M is an integer. The test system includes:

[0007] The testing equipment has N communication channels, each communication channel including a first signal communication channel and a second signal communication channel; N is an integer greater than or equal to 2, and N is less than M;

[0008] The path selection module includes two sets of sub-selection modules. Each set of sub-selection modules is electrically connected between the target position signal communication channel of the test equipment and each target position signal line of the ECU. The target position signal communication channel is either the first signal channel or the second signal channel. Correspondingly, the target position signal line is either the first signal line or the second signal line.

[0009] The path selection module includes a control signal input terminal, which is used to receive external control commands to change the physical connection path between the target position signal line of the ECU and the target position signal communication channel of the test equipment.

[0010] According to any of the foregoing embodiments of this application, the path selection module is a relay module, and the relay module includes at least one set of relay sub-modules;

[0011] The relay sub-module is electrically connected between the target position signal communication channel of the test equipment and each target position signal line of the ECU; the target position signal communication channel is either the first signal channel or the second signal channel; correspondingly, the target position signal line is either the first signal line or the second signal line.

[0012] The relay sub-module includes a control signal input terminal, which is used to receive external control commands to control the relays in the relay sub-module to switch on / off states, thereby changing the physical connection path between the target position signal line of part of the ECU and the target position signal communication channel of part of the test equipment.

[0013] According to any of the foregoing embodiments of this application, the relay sub-module includes multiple cascaded relay layers; the number of relays on each cascaded relay layer gradually decreases from the ECU side to the test equipment side.

[0014] According to any of the foregoing embodiments of this application, the relay in the relay sub-module is a single-pole double-throw relay.

[0015] According to any of the foregoing embodiments of this application, the multi-layer cascaded relay layers sequentially include layer 1, ... layer i, ... layer P, from the ECU side to the test equipment side; i is an integer greater than or equal to 2; P = MN; the number of relays on the layer 1 is M-1, the number of relays on the layer P is N, and the number of relays on the layer i is Mi.

[0016] According to any of the foregoing embodiments of this application, the M-channel CAN bus includes the first to the M-channel CAN bus;

[0017] The first terminal of the relay on the first layer of relays is connected to the target bit signal line of the CAN bus from the first to the (M-1)th channel.

[0018] The second terminal of the relay on the first layer of relays is connected to the target bit signal line of the CAN bus from the second to the (M-1)th channel;

[0019] The third terminal of the relay on the first layer of relays is connected to the first or second terminal of the relay on the i-th layer of relays;

[0020] The third terminal of the relay on the i-th relay layer is connected to the first or second terminal of the relay on the (i+1)-th relay layer.

[0021] The third terminal of the relay on the P-layer relay is connected to the target bit signal communication channel of the N-channel communication channel of the test equipment.

[0022] According to any of the foregoing embodiments of this application, the multi-layer cascaded relay layer further includes a 0th relay layer that is closer to the ECU than the 1st relay layer; the number of relays on the 0th relay layer is M; the M-channel CAN bus includes the 1st to the Mth CAN bus.

[0023] The first terminal of the relay on the 0th layer is connected to the target bit signal line of the 1st to Mth CAN bus;

[0024] The second terminal of the relay on the 0th layer is connected to the target bit signal line of the 1st to Mth CAN bus;

[0025] The third terminal of the relay on the 0th relay layer is connected to the first or second terminal of the relay on the 1st relay layer;

[0026] The third terminal of the relay on the first layer of relays is connected to the first or second terminal of the relay on the i-th layer of relays;

[0027] The third terminal of the relay on the i-th relay layer is connected to the first or second terminal of the relay on the (i+1)-th relay layer.

[0028] The third terminal of the relay on the P-layer relay is connected to the target bit signal communication channel of the N-channel communication channel of the test equipment.

[0029] The routing test system of this application embodiment is used to test a multi-bus electronic control unit (ECU). The ECU includes M CAN buses, each CAN bus including a first signal line and a second signal line. The routing test system includes a path selection module, which comprises two sets of sub-selection modules. One end of each sub-selection module is connected to the target bit signal communication channel of all N channels of the test equipment, and the other end is connected to the target bit signal lines of all M buses of the ECU. The path selection module also includes a control signal input terminal. By receiving external control commands to this control signal input terminal, the physical connection path between some target bit signal lines of the ECU and some target bit signal communication channels of the test equipment can be dynamically and automatically changed. Therefore, this application embodiment can achieve routing test coverage of all buses through rapid switching of the selection module, greatly improving test efficiency. This avoids the need for testers or routing test scripts to manually plug and unplug cables during testing. Attached Figure Description

[0030] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of a routing test system provided in one embodiment of this application;

[0032] Figure 2 This is a schematic diagram of the structure of a routing test system provided in another embodiment of this application;

[0033] Figure 3 This is a schematic diagram of the structure of a routing test system provided in another embodiment of this application;

[0034] Figure 4 This is a schematic diagram of the structure of a relay in a routing test system provided in one embodiment of this application. Detailed Implementation

[0035] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0036] It should be noted that, in this document, relational terms such as "first" and "second" are used merely 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 a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0037] Currently, CANoe is widely used as the mainstream testing platform for testing automotive electronic control units (ECUs), especially gateways and other ECUs involving multiple buses. Existing testing methods heavily rely on manual operation; test engineers need to read and understand the test case requirements, and then manually and physically plug and unplug cables to connect the specific bus to be tested on the ECU to the limited communication channels on the CANoe hardware module.

[0038] However, limited by the physical specifications of the CANoe hardware interface, a single device can typically only provide a maximum of four independent communication channels (e.g., four CAN channels). When the number of buses (M) of the ECU under test is greater than the number of channels (N) of the test device (i.e., M>N, commonly M=6, 8 or even more), parallel connection and testing of all buses cannot be achieved. The tester must first test four of the buses, and after the test is completed, manually plug and unplug the cables to switch the device channels to the other four buses for the next round of testing. This process is repeated multiple times until all buses are covered.

[0039] This method cannot support parallel testing of multiple buses, and the serial testing method results in a long testing cycle, which cannot adapt to the rapid iterative development pace. Frequent manual plugging and unplugging operations can easily cause physical wear, poor contact, or even damage to the CANoe device interface and test cable connectors. Operational errors (such as hot-plugging or misplugging) may also cause short circuits, resulting in permanent damage to expensive test equipment hardware.

[0040] To address the problems of existing technologies, this application provides a routing test system. This routing test system is used to test a multi-bus electronic control unit (ECU), which includes M CAN buses, each CAN bus including a first signal line and a second signal line.

[0041] It should be noted that the first and second signal lines are defined based on the CAN bus communication protocol characteristics used by multi-bus ECUs (such as CCU gateways in the automotive field). They can be considered two core signal lines in the CAN bus used for differential signal transmission, and are used in pairs to achieve stable message data transmission. Specifically, the first signal line can be the high-potential portion primarily transmitting the differential signal, and the second signal line can be the low-potential portion primarily transmitting the differential signal. Data transmission is achieved through a level difference, and this differential transmission method effectively resists electromagnetic interference in automotive electronic systems, ensuring stable message signal transmission. Therefore, the routing test system in this embodiment of the application needs to design path selection for both the first and second signal lines simultaneously.

[0042] The routing test system provided in the embodiments of this application will be introduced first below.

[0043] Figure 1 A schematic diagram of the routing test system provided in one embodiment of this application is shown. See also, as an example, [link to example]. Figure 1 As shown, the electronic control unit ECU103 may include 6 CAN buses U1-U6, the first signal lines corresponding to CAN buses U1-U6 are UH1-UH6 respectively, and the second signal lines corresponding to CAN buses U1-U6 are UL1-UL6 respectively.

[0044] As an example, the routing test system of this application embodiment may include: test device 101 and path selection module 102.

[0045] As an example, the test equipment can be CANOE hardware, used to send test signals, receive message signals from the ECU, and detect message cycle and routing functions.

[0046] It should be noted that, as an example, the path selection module 102 includes, but is not limited to, any electronic switching device or combination thereof that can control the connection and disconnection of its internal path through electrical signals, such as relay modules, analog switch arrays, multiplexers (MUX), demultiplexers (DEMUX) integrated circuits.

[0047] As an example, test device 101 has N communication channels, each communication channel including a first signal communication channel and a second signal communication channel; N is an integer greater than or equal to 2, and N is less than M. See, for example, [link to relevant documentation]. Figure 1 As shown, the test device 101 may include four communication channels C1-C4. The first signal communication channels corresponding to the communication channels C1-C4 are CH1-CH4, and the second signal communication channels corresponding to the communication channels C1-C4 are CL1-CL4.

[0048] For example, the first signal communication channel and the second signal communication channel can be signal transmission channels on the test equipment side that correspond one-to-one with the first signal line and the second signal line on the ECU side. They are used to carry out the differential signal transmission of the CAN bus between the test equipment and the ECU, and can be the physical interface for the test equipment to implement message sending, receiving and detection.

[0049] The first signal communication channel can be a high-potential communication channel on the hardware of the test equipment (such as CANOE), that is, a dedicated channel for connecting the first signal line on the ECU side. Its function can be to transmit the high-potential part of the differential signal, that is, to receive the first signal line signal sent by the ECU, or to send the first signal line signal required for testing to the ECU. The first signal communication channel and the first signal line of the ECU together constitute the transmission path of the high-level signal.

[0050] The second-bit signal communication channel can be a low-potential communication channel on the hardware of the test equipment (such as CANOE), that is, a dedicated channel for connecting the second-bit signal line on the ECU side. Its function can be to transmit the low-potential part of the differential signal, that is, to receive the second-bit signal line signal sent by the ECU, or to send the second-bit signal line signal required for the test to the ECU, forming a low-level signal transmission path together with the ECU's second-bit signal line.

[0051] Path selection module 102, see Figure 2 As shown, the device includes two sets of sub-gating modules 201 and 202, each set electrically connected between the target bit signal communication channel of the test device 101 and each target bit signal line of the ECU 103. The target bit signal communication channel is either a first bit signal channel or a second bit signal channel; correspondingly, the target bit signal line is either a first bit signal line or a second bit signal line. For example, sub-gating module 201 is electrically connected between the first bit signal channel of the test device 101 and each first bit signal line of the ECU 103, and sub-gating module 202 is electrically connected between the second bit signal channel of the test device 101 and each second bit signal line of the ECU 103.

[0052] As an example, when it is necessary to establish a connection between the first signal line of a certain bus on the ECU side and the test equipment 101, the target bit is the first bit. In this case, the target bit signal communication channel can refer to the first signal communication channel (such as CH1 or CH2) on a certain communication channel of the test equipment 101.

[0053] As another example, when it is necessary to establish a connection for the second bit signal line on the ECU side, the target bit is the second bit. In this case, the target bit signal communication channel can refer to the second bit signal communication channel (such as CL1 or CL2) on the corresponding channel of the test device 101.

[0054] Furthermore, since the CAN bus of the electronic control unit ECU103 uses differential signal transmission, the connection paths of the first and second signal lines must be switched simultaneously in pairs to ensure the integrity of the communication link and signal quality. Therefore, the path selection module 102 in this embodiment includes two parallel selection systems: one for selecting the first signal lines on all buses, i.e., sub-selection module 201, and the other for selecting the second signal lines on all buses, i.e., sub-selection module 202. The selection control logic of these two systems is synchronized to ensure that differential signal lines from the same bus are always switched to the same communication channel of the test device 101.

[0055] See Figure 1 The path selection module 102 includes a control signal input terminal 104, which is used to receive external control commands to change the physical connection path between the partial target position signal line of the ECU 103 and the partial target position signal communication channel of the test equipment.

[0056] As another embodiment of this application, the path selection module 102 can also be implemented using a multi-channel analog switch array chip based on semiconductor technology. The multiplexing module also includes a control signal input terminal 104 for receiving control commands sent by an external control unit, thereby realizing the physical connection between the signal line of ECU 103 and the communication channel of test equipment 101.

[0057] The routing test system of this application embodiment is used to test a multi-bus electronic control unit (ECU). The ECU includes M CAN buses, each CAN bus including a first signal line and a second signal line. The routing test system includes a path selection module, which comprises two sets of sub-selection modules. One end of each sub-selection module is connected to the target bit signal communication channel of all N channels of the test equipment, and the other end is connected to the target bit signal lines of all M buses of the ECU. The path selection module also includes a control signal input terminal. By receiving external control commands to this control signal input terminal, the physical connection path between some target bit signal lines of the ECU and some target bit signal communication channels of the test equipment can be dynamically and automatically changed. Therefore, this application embodiment can achieve routing test coverage of all buses through rapid switching of the selection module, greatly improving test efficiency. This avoids the need for testers or routing test scripts to manually plug and unplug cables during testing.

[0058] Optionally, the path selection module can be a relay module, and the sub-selection module can be a relay sub-module. Specifically, the relay sub-module can be an electromagnetic relay or a solid-state relay. It may contain at least one electronic control coil for receiving control signals, and may also contain one or more sets of mechanical contacts for changing the physical path. Exemplarily, the relay sub-module is electrically connected between the target position signal communication channel (e.g., C1 or C2) of the test equipment 1 and each target position signal line of the ECU (e.g., at least one bus from U1 to U6), realizing signal transmission path control between the test equipment and the ECU. The advantage of using a relay module in this embodiment is its low on-resistance, strong current load capacity, and high signal isolation, making it suitable for various complex electrical environments in automotive electronic testing.

[0059] Optionally, the relay sub-module may be equipped with a control signal input terminal for receiving external control commands, such as script commands integrated into the test cases. Specifically, the control signal input terminal may be an interface (such as DB9, terminal block, or network interface) on the path selection module 102, used to receive control commands sent from an external control unit (such as a PC or microcontroller). This signal is typically a high / low level signal or a serial communication command (such as UART or Modbus protocol commands). This control command can control the on / off state of the relays within the relay module, thereby changing the physical connection path between some target position signal lines of the electronic control unit ECU 103 and some target position signal communication channels of the test equipment 101, eliminating the need for manual plugging and unplugging of the connection cables.

[0060] The routing test system of this application physically implements or disconnects signal paths by controlling the combined switching of the on and off states of relay modules. This provides a stable, reliable, and easy-to-implement circuit scheme that can accurately and quickly respond to external control commands and execute changes in connection relationships, thereby ensuring the accuracy and reliability of the entire routing test system.

[0061] In one embodiment, such as Figure 3 As shown, the relay sub-module includes multiple cascaded relay layers; the number of relays on each cascaded relay layer gradually decreases from the ECU side to the test equipment side.

[0062] This application employs a multi-level relay layout to achieve flexible switching between M ECU bus channels and N test equipment channels with an optimized number of relays. Compared to a simple matrix connection (requiring M×N relays), this cascaded structure significantly reduces the number of relays, thereby lowering costs, reducing size, and improving system reliability.

[0063] As an example, a multi-layered cascaded relay system can refer to relays being logically and physically divided into multiple sequentially connected levels. The first layer, closest to the ECU, has the most relays, while the last layer, closest to the test equipment, has the fewest relays. For example, such as... Figure 3 In the first layer, there are 5 relays, and in the fourth and last layer, there are 2 relays.

[0064] As an example, external control commands simultaneously and collaboratively control relays at all levels. By assigning a unique on / off state combination to each relay at each level, a unique and continuous physical conductive path can be constructed between the ECU's M signal lines and the N channels of the test equipment.

[0065] The routing test system of this application adopts a multi-layer cascaded structure with the number of relays decreasing layer by layer. It uses a smaller number of relays to perform the selection function from a large number of ECU signal lines to a smaller number of test channels, thereby optimizing hardware cost, circuit board layout complexity, and system size. Compared to using a large number of relays to connect all possible combinations one-to-one, this hierarchical design achieves efficient utilization of hardware resources while ensuring functionality.

[0066] As an example, the relays in the relay submodule are single-pole double-throw (SPDT) relays. See also Figure 4 As shown, a single-pole double-throw relay typically includes a moving contact K3 (often called the common terminal) and two stationary contacts K1 and K2. When its coil is not energized, the moving contact K3 is connected to the normally closed contact K1; when the coil is energized, the moving contact K3 closes and connects to the normally open contact K2. In the embodiments of this application, the function of the single-pole double-throw relay is that its common terminal K3 (moving contact) serves as a signal input or output terminal, while the two stationary contacts K1 and K2 provide two selectable physical paths.

[0067] As an example, this application uses SPDT relays instead of other types, based on their unique two-to-one path selection capability, which is consistent with the core idea of ​​layer-by-layer two-to-one routing in this application.

[0068] As an example, in a hierarchical structure, each relay in each level can function as a two-to-one switch. Its two stationary contacts connect to the common terminal of two different relays in the previous level or to two adjacent signal lines of the ECU; its common terminal then connects to the stationary contacts of the relays in the next level. See also... Figure 3The layer closest to ECU103 is designated as layer 1, and layers 2, 3, and 4 are designated as layers above it. Taking the first relay on the far left of layer 1 as an example: its first terminal K1 and second terminal K2 are connected to UH1 and UH2 of ECU103, respectively; its third terminal K3 is connected to the third terminal K3 of the first relay on the far left of layer 2.

[0069] By controlling the state of this SPDT relay, signals from the previous level can be routed to one of two different branches in the next level, thus gradually converging multiple signals into fewer paths. This one-in-two-out selection function is the basic unit for building the entire pyramid-shaped gating network.

[0070] It is understandable that the single-pole double-throw function can also be achieved through a combination of other electronic components with similar switching capabilities. However, considering cost, reliability, and signal integrity, the SPDT relay is the preferred implementation scheme for automotive testing applications.

[0071] The routing test system of this application uses SPDT relays to construct the gating network, achieving maximum connection flexibility with a minimal number of relays and minimizing hardware cost and complexity. At any given time, an SPDT relay can only guide a signal in one of two directions. This fundamentally avoids the possibility of short circuits or conflicts between signals from different ECU buses within the gating network, ensuring test accuracy and equipment safety. Furthermore, SPDT relay technology is mature, with low on-resistance and high isolation, reliably transmitting automotive bus signals without introducing additional losses or noise.

[0072] As an example, the multi-layer cascaded relay layers, in order from the ECU side to the test equipment side, include layer 1, ... layer i, ... layer P; i is an integer greater than or equal to 2; P = MN; the number of relays on the layer 1 is M-1, the number of relays on the layer P is N, and the number of relays on the layer i is Mi.

[0073] As an example, the total number of layers P is equal to the difference between the number of buses M and the number of channels N, i.e., P = MN. In other words, compressing M signals onto N channels can be achieved through P selection and aggregation processes. For example, if M = 6 buses and N = 2 channels, then P = 4 layers of relays are needed to complete this signal routing.

[0074] The number of relays required for each layer is calculated using the following formula, where i is the layer number.

[0075] K i =Mi(1)

[0076] To better understand the above relationship, see [link to relevant documentation]. Figure 3 The following example illustrates the concept of M=6 (the ECU has 6 buses) and N=2 (using 2 channels of CANoe):

[0077] Total number of floors P = MN = 6 - 2 = 4 (floors);

[0078] Number of relays in the first layer = M-1 = 5 (relays);

[0079] The number of relays in the second layer = M - 2 = 4 (relays);

[0080] Number of relays in the third layer = M - 3 = 3 (relays);

[0081] The number of relays in the 4th layer (Pth layer) = N = 2 (relays);

[0082] Sub-gating module 201 (see Figure 2 The total number of relays required is S = 5 + 4 + 3 + 2 = 14. Sub-gating module 202 corresponds to sub-gating module 201 (see...). Figure 2 ), and also requires 14 relays. Therefore, in this embodiment, the path selection module 2 requires 14 + 14 = 28 relays.

[0083] The routing test system of this application quantifies the specific design parameters of the hierarchical relay gating network. It clearly specifies the total number of layers P and the specific number of relays required for each layer. This makes the structure of the relay sub-modules more specific and standardized. This hierarchical design with decreasing numbers can accurately match the difference between the number of ECU buses and the number of communication channels of the test equipment, ensuring accurate gating from M ECU signals to N test equipment channels. This improves the targeting and effectiveness of path gating and facilitates the standardized design and production of the system.

[0084] As an example, an M-channel CAN bus includes CAN channels 1 through M.

[0085] The first terminal of the relay on the first layer of relays is connected to the target bit signal line of the CAN bus from the first to the (M-1)th channel; the second terminal of the relay on the first layer of relays is connected to the target bit signal line of the CAN bus from the second to the (M-1)th channel; the third terminal of the relay on the first layer of relays is connected to the first or second terminal of the relay on the i-th layer of relays; the third terminal of the relay on the i-th layer of relays is connected to the first or second terminal of the relay on the (i+1)-th layer of relays; the third terminal of the relay on the P-th layer of relays is connected to the target bit signal communication channel of the N-channel communication channel of the test equipment.

[0086] As an example, the first terminal could be a stationary contact of a relay (e.g., a normally closed contact). See also Figure 3 and Figure 4 The first terminal K1 of the first relay on the first floor can be connected to the signal line UH1 of the first bus; the first terminal K1 of the second relay on the first floor can be connected to the signal line UH2 of the second bus; ...; the first terminal K1 of the (M-1)th relay on the first floor can be connected to the signal line of the (M-1)th bus.

[0087] As an example, the second terminal could be another stationary contact of the relay (e.g., a normally open contact). See also Figure 3 and Figure 4 The second terminal K2 of the first relay on the first floor can be connected to the signal line UH2 of the second bus; the second terminal K2 of the second relay on the first floor can be connected to the signal line UH3 of the third bus; ...; the second terminal K2 of the (M-1)th relay on the first floor can be connected to the signal line of the Mth bus.

[0088] With this design, each relay in the first layer has two stationary contacts (the first terminal K1 and the second terminal K2) connected to two adjacent numbered buses (e.g., the first relay in the first layer is connected to buses UH1 and UH2, the second relay is connected to buses UH2 and UH3, and so on). By controlling the state of the relay, one of these two adjacent buses can be selected to output its signal.

[0089] As an example, the third terminal K3 can be the common terminal of the relay, that is, the output terminal of the relay. The third terminal K3 can be connected to the first terminal K1 or the second terminal K2 of the next layer. When the relay is located at the P-th layer, that is, at the last layer of the entire path selection module 102, the third terminal can be connected to any communication channel (any one of C1-C4) of the test device 101.

[0090] This rule ensures that every bus signal from the ECU has a unique potential path that runs through all levels, ultimately allowing it to be routed to any test device channel. The core of this connection rule lies in the cross-interconnection of the output of the previous layer with the input of the next layer, thus forming a vast, controllable gating network.

[0091] By coordinating the control of all relays, the signals of buses U1, U2, U3, U4, U5, or U6 can be selected to be ultimately routed to the single test device 101.

[0092] The routing test system of this application defines the connection relationship of relays at each layer. Specifically, the relays at the first layer connect the 1st to M-1th and 2nd to Mth ECU target position signal lines, and the third terminal of each relay at each layer is sequentially connected to the corresponding terminal of the relay at the next layer. Finally, the Pth layer connects to the test equipment channel. This makes the signal path selection logic clear and unambiguous, ensuring the orderly and accurate transmission of signals from the ECU to the test equipment. It realizes the orderly adaptation of multi-bus ECU signals to test equipment with fewer channels, and improves the reliability and stability of the test system.

[0093] The multi-layer cascaded relay layer also includes a 0th relay layer that is closer to the ECU than the 1st relay layer; the number of relays on the 0th relay layer is M; the M CAN buses include the 1st to the Mth CAN buses; the first terminal of the relay on the 0th relay layer is connected to the target bit signal line of the 1st to the Mth CAN buses; the second terminal of the relay on the 0th relay layer is connected to the target bit signal line of the 1st to the Mth CAN buses; the third terminal of the relay on the 0th relay layer is connected to the first or second terminal of the relay on the 1st relay layer; the third terminal of the relay on the 1st relay layer is connected to the first or second terminal of the relay on the i-th relay layer; the third terminal of the relay on the i-th relay layer is connected to the first or second terminal of the relay on the (i+1)-th relay layer; the third terminal of the relay on the P-th relay layer is connected to the target bit signal communication channel of the N communication channels of the test equipment.

[0094] To further improve the flexibility and reliability of the testing system, as a preferred embodiment of this application, the multi-layer cascaded relay layer also includes a 0th relay layer, which is closer to the ECU than the 1st layer.

[0095] The main purpose of introducing this layer 0 is:

[0096] This isolates the ECU's bus signals from the subsequent complex routing network, reducing the potential impact on the integrity of the ECU bus signals during network switching. It allows for the independent disconnection or connection of any bus to the entire test system via software, without altering the routing status of subsequent levels. This facilitates power-on / off testing, fault injection testing, or individual bus monitoring. It maintains fixed and consistent connection rules for levels 1 and beyond, while implementing bus on / off control independently at level 0.

[0097] The number of relays in layer 0 is exactly the same as the number of ECU buses, which is M. Each relay uniquely corresponds to one ECU bus.

[0098] As an example, the common terminal K3 (third terminal) of each relay is directly and fixedly connected to the target bit signal line of its corresponding ECU bus (e.g., the first relay of layer 0 is connected to bus 1, the second relay is connected to bus 2, and so on).

[0099] As an example, the two stationary contacts K1 and K2 (the first and second terminals) of each relay are connected together and jointly connected to the input point of the subsequent routing network (i.e., Layer 1). This parallel connection of the two stationary contacts is a key feature of Layer 0. It should be noted that for the relays of Layer 0 in this embodiment, single-pole single-throw relays can be used directly.

[0100] This connection method renders the relays in this layer no longer function as selection devices, but rather as simple normally closed switches. When its coil is not energized, the common terminal is connected to the parallel stationary contact, and the ECU bus signal is conducted to the subsequent network; when its coil is energized, the common terminal is disconnected from the stationary contact, and the bus is completely physically disconnected from the test system.

[0101] In a routing test system that includes Layer 0, the test process comprises two levels of control:

[0102] Bus-level control (Level 0): The test script first controls the relays at Level 0 to determine which buses participate in the test. Buses that need to be disconnected are de-energized (opened) by the corresponding Level 0 relays; buses that need to be connected are energized (closed) by the corresponding Level 0 relays.

[0103] Routing-level control (layer 1 to layer P): After determining the buses to be tested, specific routing selection logic is executed by controlling the relays at layers 1 to P to route the connected bus signals to the designated test equipment channels.

[0104] It is evident that the addition of Layer 0 makes the system control logic clearer and more powerful, achieving the separation of bus management and routing management.

[0105] The routing test system of this application adds a 0th relay layer (M relays) before the 1st relay layer and clarifies its connection relationship with the ECU bus and the 1st relay layer, further expanding the flexibility and coverage of path selection. It can more comprehensively select and control the M ECU bus signals, realize more diverse signal connection combinations, better cope with complex test requirements, and improve the compatibility and test capability of the test system.

[0106] The above description is merely a specific implementation of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the protection scope of this application.

Claims

1. A routing test system, characterized in that, For testing multi-bus electronic control units (ECUs), the ECU includes M CAN buses, each CAN bus including a first signal line and a second signal line, where M is an integer. The test system includes: The testing equipment has N communication channels, each of which includes a first signal communication channel and a second signal communication channel; N is an integer greater than or equal to 2, and N is less than M; The path selection module includes two sets of sub-selection modules. Each set of sub-selection modules is electrically connected between the target position signal communication channel of the test equipment and each target position signal line of the ECU. The target position signal communication channel is either the first signal channel or the second signal channel. Correspondingly, the target position signal line is either the first signal line or the second signal line. The path selection module includes a control signal input terminal, which is used to receive external control commands to change the physical connection path between the target position signal line of the ECU and the target position signal communication channel of the test equipment.

2. The routing test system according to claim 1, characterized in that, The path selection module is a relay module, and the relay module includes two sets of relay sub-modules; Each relay sub-module is electrically connected between the target position signal communication channel of the test equipment and each target position signal line of the ECU; the target position signal communication channel is either the first signal channel or the second signal channel; correspondingly, the target position signal line is either the first signal line or the second signal line. The relay module includes a control signal input terminal, which is used to receive external control commands to control the relays in the relay module to switch on / off states, thereby changing the physical connection path between the target position signal line of the ECU and the target position signal communication channel of the test equipment.

3. The routing test system according to claim 2, characterized in that, The relay sub-module includes multiple cascaded relay layers; the number of relays on each cascaded relay layer gradually decreases from the ECU side to the test equipment side.

4. The routing test system according to claim 3, characterized in that, The relays in the relay sub-module are single-pole double-throw relays.

5. The routing test system according to claim 4, characterized in that, The multi-layer cascaded relay layers, arranged sequentially from the ECU side to the test equipment side, include layer 1, ... layer i, ... layer P; i is an integer greater than or equal to 2; P = MN; the number of relays on the first layer is M-1, the number of relays on the P layer is N, and the number of relays on the i layer is Mi.

6. The routing test system according to claim 5, characterized in that, The M-channel CAN bus includes the 1st to the Mth CAN bus; The first terminal of the relay on the first layer of relays is connected to the target bit signal line of the first to M-1th CAN bus; The second terminal of the relay on the first layer of relays is connected to the target bit signal line of the second to the (M-1)th CAN bus. The third terminal of the relay on the first layer of relays is connected to the first or second terminal of the relay on the i-th layer of relays; The third terminal of the relay on the i-th relay layer is connected to the first or second terminal of the relay on the (i+1)-th relay layer. The third terminal of the relay on the P-th layer relay is connected to the target bit signal communication channel of the N-channel communication channel of the test equipment.

7. The routing test system according to claim 5, characterized in that, The multi-layer cascaded relay layer also includes a 0th relay layer that is closer to the ECU than the 1st relay layer; the number of relays on the 0th relay layer is M; the M-channel CAN bus includes the 1st to the Mth CAN bus. The first terminal of the relay on the 0th layer relay is connected to the target bit signal line of the 1st to Mth CAN bus; The second terminal of the relay on the 0th layer relay is connected to the target bit signal line of the 1st to Mth CAN bus; The third terminal of the relay on the 0th relay layer is connected to the first or second terminal of the relay on the 1st relay layer; The third terminal of the relay on the first layer of relays is connected to the first or second terminal of the relay on the i-th layer of relays; The third terminal of the relay on the i-th relay layer is connected to the first or second terminal of the relay on the (i+1)-th relay layer. The third terminal of the relay on the P-th layer relay is connected to the target bit signal communication channel of the N-channel communication channel of the test equipment.

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