Spacecraft high-reliability serial bus cable ring backup connection method

Abstract

A high-reliability serial bus cable ring backup connection method for a spacecraft comprises the steps that two electric connectors P1 and P2 are arranged at the BC end of each serial bus cable, an access A and an access B are arranged in the P1 and the P2, contacts of the access A and the access B in the P1 and the P2 are divided into transmission contacts and interconnection contacts respectively, interconnection of the access A and the access B of the P1 and the access B of the P2 is achieved through the interconnection contacts, and the transmission contacts and the interconnection contacts are connected through the transmission contacts and the interconnection contacts. Mutual backup of the signal source end A single machine and the signal source end B single machine is realized; a bus signal of a corresponding path is divided into two parts through a branching module behind a transmission contact of an A path and a B path of each serial bus cable, one branching channel serves as a transmission channel, and the other branching channel is connected with an RT terminal single machine; a branching module is additionally arranged behind a transmission channel, the transmission channel is continuously divided into two parts through the branching module, one branching channel serves as the transmission channel, and the other branching channel is connected with an RT terminal single machine. And so on, the last two branching channels which are divided into two are connected with the RT terminal single machine. Each RT terminal single machine is provided with an electric connector, two sets of serial bus contacts S1 and S2 are arranged in the electric connector, and the serial bus contacts S1 and S2 respectively correspond to branching channels of an A path and a B path and an A control circuit and a B control circuit in the single machine.

Description

Technical Field

[0001] The invention relates to a high-reliability serial bus cable ring backup connection method for a GEO orbit spacecraft, and can be widely applied to spacecraft with complex payload configurations. Background Art

[0002] The increasing reliability requirements for data transmission on orbit in modern spacecraft require the reliability of spacecraft data transmission to be improved and the uncertainty of cables on spacecraft to be reduced. To this end, spacecraft serial bus cables use a variety of backup methods to achieve redundant backup of signal transmission capabilities. Currently, there are three main backup methods for serial bus cables, namely cold backup, hot backup and warm backup. The first cold backup method uses two sets of parallel bus cables. The device end powers on one set of bus cables and powers off the other set of bus cables. The bus cable is in a cold backup state, and the two sets of bus cables are not connected on the path, so the switching needs to be realized by a single device. The disadvantage is that the device switching requires a certain running time, which may cause the interruption of the spacecraft signal transmission; the second hot backup mode is to power on the device end at the same time through two sets of parallel bus cables, and transmit signals at the same time, and work as a backup for each other. When a set of bus cables fails, the signal transmission can be seamlessly switched. The disadvantage is that both paths need to be powered on and run, occupying the spacecraft system resources and the cost is high; the third warm backup is to power on the device end through two sets of parallel bus cables at the same time, and control the power consumption at the device end, so that a set of bus cable paths is in low power consumption operation. The disadvantage is that it is relatively complicated to implement and requires refined state management and control at the single end. It can be seen that the current serial bus backup methods are realized by bus physical backup and single device end simultaneous control. With the large-scale application of serial bus cables in the aerospace field, the problem of ensuring the high quality and high reliability of spacecraft signal transmission needs to be solved urgently, which requires the serial bus cable itself to have a reliable backup capability. Therefore, it is necessary to design a high-reliability serial bus cable ring backup connection method for spacecraft. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the existing serial bus backup method and provide a spacecraft high-reliability serial bus cable ring backup connection method, thereby improving the on-orbit reliability of the bus cable.

[0004] The technical solution of the present invention is: a spacecraft high-reliability serial bus cable ring backup connection method, comprising:

[0005] Two electrical connectors P1 and P2 are provided at the BC end of each serial bus cable. A and B paths are provided in the electrical connectors P1 and P2. The contacts of the A and B paths in the electrical connectors P1 and P2 are respectively divided into transmission contacts and interconnection contacts. The interconnection contacts are used to realize the interconnection of the A and B paths of the electrical connectors P1 and P2.

[0006] After the transmission connection point of each serial bus cable A and B channel, the bus signal of the corresponding channel is divided into two by a branching module to obtain two branching channels; one branching channel is used as a transmission channel, and the other branching channel is connected to the RT terminal stand-alone;

[0007] Add a branching module after the transmission channel, and continue to divide it into two through the branching module to obtain two branching channels, one of which is used as a transmission channel, and the other is connected to the RT terminal stand-alone; and so on, the last two branching channels are both connected to the RT terminal stand-alone;

[0008] Each RT terminal is equipped with an electrical connector, which has two sets of serial bus contacts S1 and S2 inside, corresponding to the branching channels of the A and B paths of the serial bus cable and the A and B control circuits inside the single machine respectively.

[0009] Preferably, the redundant backup of serial bus cable A and B paths is achieved by:

[0010] According to the bus cable signal transmission requirements, a corresponding number of contacts are selected from the A and B paths of the electrical connectors P1 and P2, and the contacts are divided into three groups, one group of which is used as signal transmission contacts for the paths, and the other two groups of contacts are used as interconnection contacts for interconnection. The interconnection method is that the interconnection contacts of the A and B paths in the electrical connector P1 are respectively connected to the interconnection contacts of the A and B paths in the electrical connector P2 through cables.

[0011] Preferably, on the A / B path, the N end is the incoming end, and the bus signal V(A / B) is introduced, and the M end is the outgoing end. The bus signal V(A / B) is divided into V(A / B)1 and V(A / B)2 by the branching module. The bus signal V(A / B) cable and the branching signal V(A / B)1 cable serve as the main cables of the A / B path for signal transmission, and the branching signal V(A / B)2 cable serves as the transmission path of the A / B path of the RT terminal.

[0012] Preferably, the branching modules of the A-channel and B-channel cables are installed in an insulated manner and stacked up and down, and there is no electrical connection between the A-channel and the B-channel in the module.

[0013] Preferably, the serial bus contacts of the S1 group and S2 group of each RT terminal stand-alone are consistent, and the address code is used to distinguish the stand-alone status. When the positions of individual stands are interchanged, the setting of the RT-end electrical connector does not need to be changed.

[0014] Preferably, the electrical connector is a space-grade electrical connector with standard density.

[0015] A spacecraft high-reliability serial bus cable ring backup system, comprising a serial bus cable, a space-grade electrical connector, a branching module, and an RT terminal;

[0016] Each serial bus cable BC end is provided with two space-grade electrical connectors P1 and P2 of standard density, and the electrical connectors P1 and P2 are provided with A and B channels, and the contacts of the A and B channels in the electrical connectors P1 and P2 are respectively divided into transmission contacts and interconnection contacts, and the interconnection contacts of the A and B channels in the electrical connector P1 are respectively connected to the interconnection contacts of the A and B channels in the electrical connector P2 through interconnection cables;

[0017] After the line splitting module is connected to the transmission connection point, the number of line splitting modules is the number of required RT terminal units minus 1; the line splitting module is used to split the bus signal of the corresponding path into two, so as to obtain two line splitting channels; one of the line splitting channels is used as a transmission channel, and the other line splitting channel is connected to the RT terminal unit; the transmission channel continues to connect to the line splitting module, and continues to be split into two, one line splitting channel is connected to the RT terminal unit, and the other is used as a transmission channel, and so on, until the last line splitting module is connected, and the two line splitting channels after being split into two are each connected to one RT terminal unit;

[0018] The RT terminal is equipped with a standard density electrical connector, and two sets of serial bus contacts S1 and S2 are arranged inside the electrical connector, which correspond to the branching channels of the A / B path of the serial bus cable and the A / B control circuit inside the single machine respectively.

[0019] Preferably, the electrical connectors P1 and P2 of each serial bus cable are respectively connected to a single machine A and a single machine B which serve as backup for each other, and the single machine A and the single machine B serve as signal source ends of the serial bus cable.

[0020] A fault handling method implemented by using the spacecraft high-reliability serial bus cable ring backup system comprises:

[0021] When the cable connected to the electrical connector P1 fails, but the A unit is normal, the A unit controls the RT terminal unit on the faulty path through the interconnection cable of the electrical connectors P1 and P2 and the cable connected to the P2 electrical connector;

[0022] When the cable connected to the electrical connector P1 is normal, but the A unit fails, the B unit can control the RT terminal on the fault path through the interconnection cable of the electrical connectors P1 and P2, the cable of the P1 electrical connector or the cable of the P2 electrical connector;

[0023] When the cable connected to the electrical connector P2 fails, but the B unit is normal, the B unit controls the RT terminal unit on the faulty path through the interconnection cable of the electrical connectors P1 and P2 and the cable connected to the P1 electrical connector;

[0024] When the cable connected to the electrical connector P2 is normal, but the B unit fails, the A unit can control the RT terminal unit on the faulty path through the interconnecting cable of the electrical connectors P1 and P2, through the cable of the P2 electrical connector or the cable of the P1 electrical connector.

[0025] The beneficial effects of the present invention compared with the prior art are:

[0026] This solution proposes a ring backup connection method for serial bus cables, creatively proposes to cooperate with a single machine at the BC end to interconnect the A / B channels, split the signal into two by a branching module, and design the consistency of the connector contacts of the RT terminal equipment. Through the coordinated design of the three parts of the serial bus cable, the combined serial bus cable has the characteristics of light weight, diverse redundant backup means, and strong reliability.

[0027] Light weight: Compared with traditional cable design, this design reduces the number of wires from the BC end to the RT terminal device due to the setting of the branching module, and the overall weight is reduced by 40%.

[0028] There are various redundancy backup methods. The redundant designs such as interconnection wires, branching modules and RT terminal contact settings at the BC end are combined together to form a serial bus cable with zero single point failure mode.

[0029] Strong reliability and reliable information transmission are the basic requirements for testing the quality of spacecraft. Improving the system's redundant backup method and achieving zero failure mode in hardware is an important trend in the development of spacecraft cable networks. Therefore, a reliable serial bus cable backup connection method is designed to further reduce the single point failure mode of the spacecraft system. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of serial bus cable connection;

[0031] Figure 2 This is the connection diagram of the serial bus BC terminal;

[0032] Figure 3 It is the connection relationship of the branching module;

[0033] Figure 4 Designed for single-machine contact of RT target. DETAILED DESCRIPTION

[0034] The present invention will be further described below in conjunction with the embodiments.

[0035] This scheme designs a ring backup connection method for serial bus cables. By innovating the connection method of the BC end electrical connector, the branching module and the RT terminal electrical connector on the serial bus cable, the redundant design of the serial bus cable is realized and the reliability is improved. This new serial bus cable connection method is a ring backup connection method, which completely eliminates the single point failure mode of the serial bus cable.

[0036] 1) The first step: establish the connection relationship between the BC terminal plug-in

[0037] In this design, two space-grade electrical connectors of standard density, P1 and P2, are provided at the BC end of each serial bus cable. The cable adopts shielded six-twisted conductor. According to the signal transmission requirements and contact design requirements of the bus cable, 18 contacts (the serial bus adopts a 6-wire system) are selected in the A channel of the P1 electrical connector as transmission contacts of the A channel serial bus, and the 6 contacts (denoted as A1 to A6) selected in the A channel are used for signal transmission, and the remaining 12 contacts are divided into 2 groups as interconnection contacts, and each group of 6 contacts (all A1 to A6) is used as an interconnection channel to be interconnected with the P2 electrical connector; 18 contacts (the serial bus adopts a 6-wire system) are also selected in the B channel of the P1 electrical connector as transmission contacts of the B channel serial bus, and the 6 contacts (all B1 to B6) selected in the B channel are used for signal transmission, and the remaining 12 contacts are divided into 2 groups as interconnection contacts, and each group of 6 contacts (all B1 to B6) is used as an interconnection channel to be interconnected with the P2 electrical connector. The four sets of contacts on the P1 and P2 electrical connectors used for interconnection are connected through cables. The connection method is A1~A6 on the P1 electrical connector and A1~A6 on the P2 electrical connector, and the connection method is B1~B6 on the P1 electrical connector and B1~B6 on the P2 electrical connector. After the connection, the A / B paths in the two electrical connectors P1 and P2 at the BC end are interconnected, and the redundant backup of the A / B paths of the serial bus cable is realized; thereby, the A / B paths in the signal source end A and B single machines are interconnected, and the signal source end A and B single machines can independently control the RT terminal single machine on the A path or B path of the serial bus cable. For the design drawing, see Figure 2 .

[0038] The electrical connectors P1 and P2 of each serial bus cable are respectively connected to a single machine A and a single machine B which serve as backup for each other. The single machine A and the single machine B serve as signal source ends of the serial bus cable.

[0039] The redundant design of the BC-end electrical connector can achieve the following:

[0040] When the cable connected to the electrical connector P1 fails, but the A unit is normal, the A unit controls the RT terminal unit on the faulty path through the interconnection cable of the electrical connectors P1 and P2 and the cable connected to the P2 electrical connector;

[0041] When the cable connected to the electrical connector P1 is normal, but the A unit fails, the B unit can control the RT terminal on the fault path through the interconnection cable of the electrical connectors P1 and P2, the cable of the P1 electrical connector or the cable of the P2 electrical connector;

[0042] When the cable connected to the electrical connector P2 fails, but the B unit is normal, the B unit controls the RT terminal unit on the faulty path through the interconnection cable of the electrical connectors P1 and P2 and the cable connected to the P1 electrical connector;

[0043] When the cable connected to the electrical connector P2 is normal, but the B unit fails, the A unit can control the RT terminal unit on the faulty path through the interconnecting cable of the electrical connectors P1 and P2, through the cable of the P2 electrical connector or the cable of the P1 electrical connector.

[0044] When designing a traditional serial bus cable, the BC-end electrical connector is not redundantly designed. Instead, after the last set of RT terminals of the serial bus cable are connected, the two serial signals are connected to achieve a backup relationship. This design results in a relatively long cable length and low reliability, and many factors need to be considered when designing the direction of the spacecraft. When designing this solution, the shortcomings of the traditional serial bus cable being long and having many factors to avoid in the direction design are avoided. The present invention proposes a new solution for redundant design inside the BC-end electrical connector, which improves the reliability of the system.

[0045] 2) Step 2: Build the branching module

[0046] Different from the traditional end-to-end and two-point two-line connection methods, the serial bus cable adopts a branching module design, which greatly reduces the length of the cable and improves the reliability of the cable. In this solution, the branching module is matched with the serial bus to achieve a one-to-two design of the main channel transmission signal of the bus cable, which reduces the length of the cable and improves the reliability of the bus cable.

[0047] The specific implementation method of the branching module is to adopt a mode in which the branching modules of the A and B channel cables are stacked and insulated and installed up and down, and the A and B channels in the module have no electrical connection relationship. On the A channel, the N end is the incoming line end, and the bus signal V(A) is introduced. The M end is the outgoing line end, and the bus signal cables V(A)1 and V(A)2 are led out. The bus signal cables V(A)1 and V(A)2 divide the same signal into two through the printed circuit board inside the branching module. The bus signal cables V(A) and V(A)1 are used as the main cables of the A channel for signal transmission, and V(A)2 is used as the signal transmission cable of the A channel of the RT terminal stand-alone; on the B channel, the N end is the incoming line end, and the bus signal V(B) is introduced. The M end is the outgoing line end, and the bus signal cables V(B)1 and V(B)2 are led out. The bus signal cables V(B)1 and V(B)2 divide the same signal into two through the printed circuit board inside the branching module. The bus signal cables V(B) and V(B)1 are used as the main cables of the B channel for signal transmission, and V(B)2 is used as the signal transmission cable of the B channel of the RT terminal. Based on the above-mentioned branching module design, the serial bus cable sets up an effective A / B channel redundancy backup between the branching module and the RT terminal, avoiding the single point failure mode of the serial bus cable and increasing the reliability of the system. Figure 3 The splitter module can use one printed circuit board to split the same signal into two.

[0048] The branching module A and branching module B are connected to the RT terminal at the same time, and cooperate with the signal source end A / B to control the RT terminal. When the transmission path fails, the specific measures are as follows:

[0049] When the A channel cable fails or the signal source end A single machine fails, V(A) has no signal input. At this time, the serial bus cable B channel is normal. The A single machine realizes the signal transmission through the B channel through the connection method of the P1 and P2 electrical connectors at the BC end. At the same time, with the redundant design of the RT terminal, the bus signal transmission and control of the RT terminal single machine are realized. The RT terminal single machine connected behind the single machine can be controlled using the above channel without affecting the signal transmission of the main channel cable.

[0050] When the cable of channel B fails or the single machine B at the signal source fails, there is no signal input to V(B). At this time, channel B of the serial bus cable is normal. The single machine B uses the connection method of the P1 and P2 electrical connectors at the BC end to realize the signal transmission of the single machine B through channel A. At the same time, with the redundant design of the RT terminal, the bus signal transmission and control of the single machine RT terminal can be realized. For the single machine terminal connected behind the single machine, the above channel can be used for control without affecting the signal transmission of the main channel cable.

[0051] When an open circuit fault occurs in the output cable V(A)2 or V(B)2 of the branch module, since V(A)1 and V(A)2, V(B)1 and V(B)2 in the branch module divide the same signal into two through the printed circuit board inside the branch module, the open circuit fault of the cable at the single machine end will not affect the signal transmission of the main line, reducing the spread of the fault and improving the reliability of the system.

[0052] 3) Step 3: RT terminal electrical connector construction

[0053] The RT terminal electrical connectors are all provided with A / B paths connected to the BC end P1 / P2 electrical connectors, and can both control a single RT terminal.

[0054] When the A channel fails, the signal source end A / B single machine can control the RT terminal single machine through the B channel.

[0055] When the B channel fails, the signal source end A / B single machine can control the RT terminal single machine through the A channel.

[0056] Each RT terminal is equipped with a standard density electrical connector. There are two groups of serial bus signals, S1 and S2, inside the electrical connector, which correspond to the A / B path of the serial bus cable and the A / B path control circuit inside the unit. When the S1 group serial bus fails, the A / B unit at the signal source end can control the B path circuit of the RT terminal unit through the S2 group serial bus to achieve control of the RT terminal unit; when the S2 group serial signal bus fails, the A / B unit at the signal source end can control the A path circuit of the RT terminal unit through the S1 group serial bus to achieve control of the RT state unit. For the design of RT terminal contacts, see Figure 4 .

[0057] The serial bus contacts of the S1 and S2 groups of each RT terminal device are consistent, and the address code is used to distinguish the status of each single machine. When the positions of individual single machines are interchanged, the settings of the RT-end electrical connector do not need to be changed, which greatly saves the cost and development progress of the spacecraft and increases the redundant design of production maintenance.

[0058] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

[0059] Parts not described in detail in the present invention belong to common knowledge of those skilled in the art.

Claims

1. A spacecraft high-reliability serial bus cable ring backup connection method, characterized in that include: Two electrical connectors P1 and P2 are provided at the BC end of each serial bus cable. A and B paths are provided in the electrical connectors P1 and P2. The contacts of the A and B paths in the electrical connectors P1 and P2 are respectively divided into transmission contacts and interconnection contacts. The interconnection contacts are used to realize the interconnection of the A and B paths of the electrical connectors P1 and P2. After the transmission connection point of each serial bus cable A and B channel, the bus signal of the corresponding channel is divided into two by a branching module to obtain two branching channels; One of the branch lines is used as a transmission channel, and the other branch line is connected to the RT terminal. Add a branching module after the transmission channel, and continue to divide it into two through the branching module to obtain two branching channels, one of which is used as a transmission channel, and the other is connected to the RT terminal stand-alone; and so on, the last two branching channels are both connected to the RT terminal stand-alone; Each RT terminal is equipped with an electrical connector, which has two sets of serial bus contacts S1 and S2 inside, corresponding to the branching channels of the A and B paths of the serial bus cable and the A and B control circuits inside the single machine respectively.

2. The method according to claim 1, characterized in that: The following methods are used to achieve redundant backup of serial bus cable A and B channels: According to the bus cable signal transmission requirements, a corresponding number of contacts are selected from the A and B paths of the electrical connectors P1 and P2, and the contacts are divided into three groups, one group of which is used as signal transmission contacts for the paths, and the other two groups of contacts are used as interconnection contacts for interconnection. The interconnection method is that the interconnection contacts of the A and B paths in the electrical connector P1 are respectively connected to the interconnection contacts of the A and B paths in the electrical connector P2 through cables.

3. The method according to claim 1, characterized in that: On the A / B path, the N end is the incoming end, where the bus signal V(A / B) is introduced, and the M end is the outgoing end. The bus signal V(A / B) is divided into V(A / B)1 and V(A / B)2 by the branching module. The bus signal V(A / B) cable and the branching signal V(A / B)1 cable are used as the main cables of the A / B path for signal transmission, and the branching signal V(A / B)2 cable is used as the transmission path for the A / B path of the RT terminal.

4. The method according to claim 1, characterized in that: The branching modules of the A channel and B channel cables are installed in an insulated manner and stacked up and down. There is no electrical connection between the A channel and the B channel in the module.

5. The method according to claim 1, characterized in that: The serial bus contacts of the S1 group and S2 group of each RT terminal are consistent, and the address code is used to distinguish the status of the single machine. When the position of individual single machines is interchanged, the setting of the RT end electrical connector does not need to be changed.

6. The method according to claim 1, characterized in that: The electrical connector is a space-grade electrical connector with standard density.

7. A spacecraft high-reliability serial bus cable ring backup system, characterized in that: Including serial bus cables, aerospace-grade electrical connectors, branching modules, and RT terminal units; Each serial bus cable BC end is provided with two space-grade electrical connectors P1 and P2 of standard density, and the electrical connectors P1 and P2 are provided with A and B channels, and the contacts of the A and B channels in the electrical connectors P1 and P2 are respectively divided into transmission contacts and interconnection contacts, and the interconnection contacts of the A and B channels in the electrical connector P1 are respectively connected to the interconnection contacts of the A and B channels in the electrical connector P2 through interconnection cables; The line splitting module is connected to the transmission point, and the number of line splitting modules is the number of required RT terminal units minus 1; the line splitting module is used to split the bus signal of the corresponding path into two, thereby obtaining two line splitting channels; One of the branching channels is used as a transmission channel, and the other branching channel is connected to a single RT terminal. The transmission channel continues to connect to the branching module and is further divided into two. One branching channel is connected to a single RT terminal, and the other is used as a transmission channel, and so on, until the last branching module is connected. After being divided into two, both branching channels are connected to a single RT terminal. The RT terminal is equipped with a standard density electrical connector, and two sets of serial bus contacts S1 and S2 are arranged inside the electrical connector, which correspond to the branching channels of the A / B path of the serial bus cable and the A / B control circuit inside the single machine respectively.

8. The system according to claim 7, characterized in that: The electrical connectors P1 and P2 of each serial bus cable are respectively connected to a single machine A and a single machine B which serve as backup for each other. The single machine A and the single machine B serve as signal source ends of the serial bus cable.

9. A fault handling method implemented by using the spacecraft high-reliability serial bus cable ring backup system of claim 8, characterized in that include: When the cable connected to the electrical connector P1 fails, but the A unit is normal, the A unit controls the RT terminal unit on the faulty path through the interconnection cable of the electrical connectors P1 and P2 and the cable connected to the P2 electrical connector; When the cable connected to the electrical connector P1 is normal, but the A unit fails, the B unit can control the RT terminal on the fault path through the interconnection cable of the electrical connectors P1 and P2, the cable of the P1 electrical connector or the cable of the P2 electrical connector; When the cable connected to the electrical connector P2 fails, but the B unit is normal, the B unit controls the RT terminal unit on the faulty path through the interconnection cable of the electrical connectors P1 and P2 and the cable connected to the P1 electrical connector; When the cable connected to the electrical connector P2 is normal, but the B unit fails, the A unit can control the RT terminal unit on the faulty path through the interconnecting cable of the electrical connectors P1 and P2, through the cable of the P2 electrical connector or the cable of the P1 electrical connector.

Images