A single-channel transmission CT system, data transmission system and transmission method

Abstract

This invention discloses a single-channel transmission CT system, data transmission system, and transmission method, comprising: a CT scanning system including a single-slide data transmission system; a scanning gantry including a slip ring and an image chain component; the image chain component including an X-ray tube, a high-voltage generator, and a detector; a CAN transceiver connected to the slip ring; and a patient support connected to the slip ring. The system allows for flexible switching between CAN and TRIG communication via multiplexing, facilitating information exchange between application software. During CT scanning, the data acquired by the detector is synchronized with information such as the gantry angle and the scanning bed position, improving the accuracy of the acquired data, maximizing compatibility with standard CAN networks, and balancing real-time performance with flexibility.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more specifically, to a single-channel transmission CT system, a data transmission system, and a transmission method. Background Technology

[0002] In high-speed rotating systems (such as CT gantry), the following long-standing technical challenges remain unresolved in communication between the rotating and stationary parts:

[0003] Channel limitations and cost issues: Traditional solutions use RS485 to transmit position pulses and CAN bus to transmit general data, requiring multiple slip ring channels, which increases the complexity of the system and manufacturing costs.

[0004] The challenges of real-time performance and determinism: The processing delay of the software CAN protocol stack based on microprocessor (MCU) is uncertain (usually in the range of microseconds to milliseconds) and is easily interfered with by other tasks. It cannot guarantee the completion of the transmission of critical data (such as encoder position) within a fixed time window, making it difficult to meet the precise timing requirements of equipment such as high-speed CT.

[0005] Limitations of the standard protocol: While the standard CAN bus protocol boasts excellent multi-master and error handling capabilities, its inherent non-destructive arbitration mechanism can still introduce unpredictable waiting delays when faced with sudden bursts of high-priority messages. In multi-node networks, it cannot be guaranteed that the rotating end can preempt the bus within a very short time window.

[0006] System safety challenge: When a critical fault (such as over-temperature or over-current) occurs at the rotating end, there is a lack of a hardware-level emergency interrupt mechanism that can immediately notify the stationary end regardless of the current bus status.

[0007] Existing technologies either sacrifice cost (increasing channels), performance (reducing speed or accuracy), or compatibility (using non-standard protocols), lacking a hardware solution that can fundamentally solve the problems of deterministic latency and emergency preemption within the framework of standard protocols. Summary of the Invention

[0008] To address at least one of the aforementioned technical problems, this invention proposes a single-channel transmission CT system, a data transmission system, and a transmission method.

[0009] The first aspect of this invention provides a single-channel transmission CT system, a data transmission system, and a transmission method, comprising:

[0010] CT scanning system, including a single-track data transmission system;

[0011] Scanning support, including slip rings and image chain components;

[0012] The imaging chain components include an X-ray tube, a high-voltage generator, and a detector;

[0013] The slip ring is connected to a CAN transceiver;

[0014] A patient stent, which is connected to a slip ring.

[0015] A second aspect of the present invention provides a single-track data transmission system, comprising:

[0016] A pair of slip ring differential transmission lines serve as the only available physical channel for data transmission in the CT scanning system;

[0017] The stationary end control unit includes a synchronization information acquisition module, an S controller, and an S-TRG communication node. The S controller includes at least one standard CAN node, S-CAN.

[0018] The rotating end control unit includes a data acquisition system, an R controller, and an R-TRG communication node. The R controller includes at least one standard CAN node, R-CAN.

[0019] The S-TRG communication node and the R-TRG communication node are connected to the slip ring differential transmission line via a CAN transceiver to form a CAN bus network;

[0020] S-TRG communication nodes and S-CAN communication nodes are interconnected via SPI or serial port.

[0021] The R-TRG communication node and the R-CAN communication node are interconnected via SPI or serial port.

[0022] The system is configured to simultaneously transmit control command data and trigger synchronization data on the single slide rail via multiplexing.

[0023] In a preferred embodiment of the present invention, the reuse method includes a first method and a second method;

[0024] The first method is software-controlled reuse, which switches between CAN communication mode and TRIG communication mode through software processes;

[0025] The second method is adaptive switching multiplexing, which automatically switches between CAN communication and TRIG communication based on bus status and transmission requirements;

[0026] During TRIG communication, the S-TRG and R-TRG nodes remain synchronized to ensure that transmission is not interrupted during a continuous data acquisition or exposure process;

[0027] In CAN communication mode, the scanning system mainly transmits parameter configuration and system status information, such as scanning exposure kV, exposure mA parameter configuration, rack speed configuration, and the readiness status of image chain components.

[0028] In TRIG communication mode, the scanning system transmits time and space synchronization information.

[0029] In a preferred embodiment of the present invention, the reuse of software control includes:

[0030] The system sets bus status indicators, including CAN communication status and TRIG communication status;

[0031] The master node controls the state switching, and the other nodes determine their own behavior based on the state flag.

[0032] In CAN communication mode, only standard CAN nodes are allowed to communicate, using the standard CAN data link layer protocol;

[0033] In TRIG communication mode, only S-TRG and R-TRG nodes are allowed to communicate, using a trigger synchronization protocol based on CAN frame format;

[0034] The triggering conditions for switching from TRIG communication state to CAN communication state include: receiving the end marker of the TRIG protocol, triggering the timeout mechanism, or a command from the master node.

[0035] In a preferred embodiment of the present invention, the adaptive switching multiplexing includes:

[0036] S-TRG and R-TRG nodes can autonomously occupy the bus without software intervention for mode switching;

[0037] By controlling the frame interval, it is ensured that the bus occupancy-idle-arbitration state defined by the standard CAN protocol is met during TRIG transmission, and that S-TRG and R-TRG repeatedly initiate transmission arbitration at the first time.

[0038] By setting the highest S-TRG and R-TRG node priorities, it is ensured that the node can successfully and continuously obtain bus access after initiating arbitration;

[0039] After completing the TRIG data transmission, the bus control is automatically released, allowing the bus to resume standard CAN communication.

[0040] A third aspect of the present invention provides a single-track data transmission method, applied to a single-track data transmission system, comprising the following steps:

[0041] A CAN bus-based communication network is established on a single pair of slip ring differential transmission lines, with all nodes connected via CAN transceivers.

[0042] Control command data and trigger synchronization data are transmitted simultaneously on the same pair of differential lines using multiplexing.

[0043] During TRIG transmission, the clocks of the STRG and RTRG nodes are kept synchronized to ensure that the transmission is not interrupted during a continuous data acquisition or exposure process;

[0044] The encoder edge is recovered based on the received timestamp information, which is used to trigger the data acquisition system.

[0045] In a preferred embodiment of the present invention, the switching conditions for the mode switching include one of receiving a frame identifier of the TRIG protocol, triggering a timeout mechanism, and receiving a manual switching instruction.

[0046] The technical solution of the present invention has the following advantages compared with the prior art:

[0047] By flexibly switching between CAN and TRIG communication through multiplexing, and flexibly switching communication protocols, information exchange between application software is facilitated. During CT scanning, the data collected by the detector is synchronized with information such as the angle of the gantry and the position of the scanning bed, improving the accuracy of the collected data, maximizing compatibility with standard CAN networks, and balancing real-time performance and flexibility. Attached Figure Description

[0048] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, some of the drawings in the following description are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0049] Figure 1 This is a block diagram of the CT system structure according to an embodiment of the present invention;

[0050] Figure 2 This is a block diagram of a CT system according to another embodiment of the present invention;

[0051] Figure 3 This is a software control flowchart of an embodiment of the present invention;

[0052] Figure 4 This is a diagram of the synchronization frame structure according to an embodiment of the present invention;

[0053] Figure 5 This is a TRIG frame structure diagram according to an embodiment of the present invention;

[0054] Figure 6 This is a schematic diagram of frame format analysis according to an embodiment of the present invention.

[0055] In the figure, 100 is the scanning bracket, 101 is the X-ray tube, 102 is the detector, 103 is the high voltage generator, 104 is the slip ring, and 105 is the position detection device.

[0056] 201. Stationary part of the scanning system; 2011. Stationary part of the transmission system; 202. Rotating part of the scanning system; 2021. Rotating part of the transmission system.

[0057] 301. Patient stent; 401. Human-computer interaction system. Detailed Implementation

[0058] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0059] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0060] Example 1

[0061] See Figure 1 As shown, this invention proposes a single-channel transmission CT system, comprising:

[0062] CT scanning system, including a single-track data transmission system;

[0063] Scanning support 100, including slip rings and image chain components;

[0064] The imaging chain components include an X-ray tube 101, a high-voltage generator 103, and a detector 102;

[0065] Slip ring 104 is connected to a CAN transceiver;

[0066] The patient stent 301 is connected to the slip ring 104.

[0067] In one embodiment of the present invention, such as Figure 2 As shown, the single-channel transmission CT system includes: a human-computer interaction system 401;

[0068] A CT scanning system includes a stationary portion 201 and a rotating portion 202 of the scanning system. The CT scanning system includes a single-track data transmission system, which includes a stationary portion 2011 and a rotating portion 2021 of the transmission system. The stationary portion 2011 and the rotating portion 2021 of the transmission system are respectively a part of the stationary portion 201 and the rotating portion 202 of the scanning system.

[0069] The scanning stand 100 includes a slip ring 104 and an image chain component;

[0070] The imaging chain components include an X-ray tube 101, a high-voltage generator 103, and a detector 102.

[0071] Patient stent 301;

[0072] The human-computer interaction system 401 is responsible for receiving, displaying, and responding to the operator's instructions, and providing the operator with the status information and images of the CT system.

[0073] The stationary part 201 of the scanning system is interconnected with the human-computer interaction system, and is responsible for converting the human-computer interaction instructions into control data streams for CT scanning and directly controlling the hardware, such as controlling the rotation of the gantry.

[0074] The rotating part 202 of the scanning system controls the high voltage generator to generate high voltage power, which is supplied to the X-ray tube 101 to generate X-rays. The detector 102 receives the X-rays passing through the human body and converts them into electrical signals, which are then digitized to generate raw data.

[0075] Meanwhile, the stationary part 201 of the scanning system also receives raw data from the detector 102, reconstructs the raw data into a CT image, and provides it to the human-computer interaction system 401. Alternatively, the rotating part 202 of the scanning system receives raw data from the detector 102, reconstructs the raw data into a CT image, and provides it to the human-computer interaction system 401. The stationary part 201 or the rotating part 202 of the scanning system provides the raw data or reconstructed image to the human-computer interaction system 401 through a high-speed non-contact rotating data transmission system or a wireless transmission system such as WIFI.

[0076] The stationary part 201 of the scanning system is responsible for interconnecting with the patient stent 301, controlling the movement of the patient stent 301 and acquiring the position information of the patient stent 301.

[0077] The patient support 301 is used to support the scanned object, which is generally part or all of the patient's body. The patient support contains at least one horizontal motion mechanism that can move the patient or remove the patient from the scanning support.

[0078] The slip ring 104 contains a single control signal transmission channel, typically with a rate of less than 10 Mbps;

[0079] The stationary part 2011 and the rotating part 2021 of the single-slide data transmission system are equipped with CAN transceivers, which are connected to the control signal transmission channel of the slip ring respectively.

[0080] The slip ring 104 also includes a position detection device 105, which is formed by coupling a photoelectric sensor with an alternating perforated grid strip arranged around the slip ring. The stationary part 2011 of the single slip track data transmission system can independently or through other circuit parts of the stationary part 201 of the scanning system obtain the slip ring position information and / or the motion position information of the patient stent 301 of the position detection device 105.

[0081] Example 2

[0082] like Figures 2-5 As shown, a second aspect of the present invention provides a single-track data transmission system, comprising:

[0083] A pair of slip ring differential transmission lines serve as the only available physical data transmission channel for the CT scanning system;

[0084] The stationary end control unit includes a synchronization information acquisition module, an S controller, and an S-TRG communication node. The S controller includes at least one standard CAN node, S-CAN.

[0085] The rotating end control unit includes a data acquisition system, an R controller, and an R-TRG communication node. The R controller includes at least one standard CAN node, R-CAN.

[0086] S-TRG communication nodes and R-TRG communication nodes are connected to the slip ring differential transmission line via CAN transceivers to form a CAN bus network;

[0087] S-TRG communication nodes and S-CAN communication nodes are interconnected via SPI or serial port.

[0088] The R-TRG communication node and the R-CAN communication node are interconnected via SPI or serial port.

[0089] The system is configured to transmit control command data and trigger synchronization data simultaneously on a single slide using a multiplexing method.

[0090] According to embodiments of the present invention, the reuse method includes a first method and a second method;

[0091] The first method is software-controlled reuse, which switches between CAN communication mode and TRIG communication mode through software processes;

[0092] The second method is adaptive switching multiplexing, which automatically switches between CAN communication and TRIG communication based on bus status and transmission requirements;

[0093] During TRIG communication, S-TRG and R-TRG nodes remain synchronized to ensure uninterrupted transmission during a continuous data acquisition or exposure process;

[0094] In CAN communication mode, the scanning system mainly transmits parameter configuration and system status information, such as scanning exposure kV, exposure mA parameter configuration, rack speed configuration, and the readiness status of image chain components.

[0095] In TRIG communication mode, the scanning system transmits time and space synchronization information.

[0096] According to embodiments of the present invention, the reuse of software control includes:

[0097] The system sets bus status indicators, including CAN communication status and TRIG communication status;

[0098] The master node controls the state switching, and the other nodes determine their own behavior based on the state flag.

[0099] In CAN communication mode, only standard CAN nodes are allowed to communicate, using the standard CAN data link layer protocol;

[0100] In TRIG communication mode, only S-TRG and R-TRG nodes are allowed to communicate, using a trigger synchronization protocol based on CAN frame format;

[0101] The triggering conditions for switching from TRIG communication state to CAN communication state include: receiving the end marker of the TRIG protocol, triggering the timeout mechanism, or a command from the master node.

[0102] like Figure 3 As shown, the software control flow is as follows:

[0103] (1) System initialization:

[0104] ① During CT system initialization, all node modes are automatically set to CAN communication mode;

[0105] (2) Switch CAN communication mode to TRIG communication mode:

[0106] ①The S controller determines whether to enter TRIG communication mode based on the workflow. If so, it notifies all nodes to enter this mode.

[0107] ② S-CAN configuration: S-TRG specifies the total number of synchronization frames to be sent in this TRIG mode;

[0108] (3) During TRIG mode:

[0109] ① Only S-TRG and R-TRG nodes are allowed to communicate;

[0110] ② S-TRG and R-TRG communicate via synchronization frames;

[0111] ③ Synchronization frame structure as follows Figure 4 As shown:

[0112] 1) Structure 1: One-way synchronization frame. This is the basic synchronization frame structure, which only contains TRIG frames, sent from S-TRG to R-TRG.

[0113] 2) Structure 2: Bidirectional synchronization frame. This is a more optimized synchronization frame structure, which includes a TRIG frame sent from S-TRG to R-TRG and a Report frame sent from R-TRG to S-TRG.

[0114] ④TRIG frame structure as follows Figure 5 As shown, the framing method is the standard CAN data frame;

[0115] 1) Includes 1-start of frame, 2-arbitration segment, 3-control segment, 4-data segment, 5-CRC segment, 6-ACK segment, 7-end of frame;

[0116] 2) The TRIG frame transmission is aligned with the synchronization pulse. The synchronization pulse is generated by real-time detection of the position encoder of the frame or scanning bed, which is usually an A / B / Z type encoder or a BISS / SSI absolute encoder.

[0117] 3) The data segment must contain at least the location information mentioned above;

[0118] 4) The data segment also contains identification information such as the start and end of the current mode and the number of synchronization frames sent;

[0119] a. A frame with a start identifier is called a start frame;

[0120] b. A frame with an end marker is called an end frame;

[0121] 5) The data segment may also contain information on whether the current synchronization frame allows the sending of a report frame.

[0122] ⑤ The Report frame structure is similar to the TRIG frame, and it is sent by the R-TRG to the S-TRG as needed;

[0123] 1) In the one-way synchronization frame implementation, no report frame is required;

[0124] 2) In the bidirectional synchronous frame implementation, after R-TRG receives a TRIG frame each time, it allows the transmission of a Report frame through data segment parsing, and then the Report frame is transmitted when the bus is detected to be idle.

[0125] 3) The report frame can contain the status information of the rotating frame, such as the working status of each component of the image chain, and whether any abnormal conditions have occurred, such as overheating or exposure failure.

[0126] (4) In TRIG mode, the system switches to CAN communication mode if the following conditions are met:

[0127] ① Normal ending:

[0128] 1) S-TRG continuously sends synchronization frames and calculates the remaining number of frames based on the total number of frames;

[0129] 2) S-TRG calculates that the current synchronization frame is the last frame and sends the end frame;

[0130] 3) S-TRG reports to S-CAN, completing the data transmission for this mode and entering CAN communication mode;

[0131] 4) When R-TRG detects the end frame, R-TRG notifies R-CAN that the current mode has ended, and R-TRG enters CAN communication mode;

[0132] 5) R-CAN enters CAN communication mode and simultaneously S-CAN;

[0133] 6) The S-CAN update identification system uses CAN communication mode;

[0134] ②End of suspension:

[0135] 1) Based on the system status, such as when the user issues a stop command (usually the CT human-machine interface includes this command), S-CAN decides to stop the current TRIG communication and notifies S-TRG to stop.

[0136] 2) After receiving the abort command, the S-TRG will send the next end frame;

[0137] 3) Superior: S-TRG can repeatedly send the end frame multiple times, ensuring that R-TRG can obtain the abort information;

[0138] 4) The subsequent procedures are the same as those in 3)-6) if the process ends normally.

[0139] ③ Abnormal termination:

[0140] 1) If S-CAN detects an anomaly, such as a rack rotation failure, it will issue a stop command, and the subsequent procedures will follow the same as the stop termination process.

[0141] 2) When R-TRG detects an anomaly or receives an anomaly detected and reported by R-CAN, it reports it to S-TRG via a Report frame;

[0142] 3) When S-TRG detects an anomaly or receives an anomaly reported by R-TRG, it reports the anomaly to S-CAN, and S-CAN initiates abort the process.

[0143] According to embodiments of the present invention, adaptive switching multiplexing includes:

[0144] S-TRG and R-TRG nodes can autonomously occupy the bus without software intervention for mode switching;

[0145] By controlling the frame interval, it is ensured that the bus occupancy-idle-arbitration state defined by the standard CAN protocol is met during TRIG transmission, and that S-TRG and R-TRG repeatedly initiate transmission arbitration at the first time.

[0146] By setting the highest S-TRG and R-TRG node priorities, it is ensured that the node can successfully and continuously obtain bus access after initiating arbitration;

[0147] After completing the TRIG data transmission, the bus control is automatically released, allowing the bus to resume standard CAN communication.

[0148] It should be noted that the main advantage of adaptive switching is that once the S-TRG initiates the transmission of a synchronization frame, it does not need to forcibly prohibit other nodes from sending data through state. The network has stronger robustness and flexibility. By continuously sending data frames through the S-TRG, it ensures that the S-TRG continuously occupies the right to use the bus. After the synchronization data transmission is completed, the bus is automatically released. Through a specially designed signal edge synchronization mechanism, it ensures that the encoder trigger edge at the S end is accurately transmitted to the R end.

[0149] The adaptive switching steps are as follows:

[0150] ① During system initialization, the default is CAN communication mode. The addresses of S-TRG and R-TRG are set to the highest priority in the entire network to ensure that these two nodes always have the advantage in bus arbitration with other conventional CAN nodes, such as S-CAN and R-CAN.

[0151] ② The system needs to enter TRIG communication mode to initiate data acquisition and / or X-ray exposure;

[0152] ③ S-CAN notifies all nodes to enter TRIG communication mode, but allows data communication to be initiated as needed within a certain period of time. This event is the preparation time for S-TRG to initiate the first synchronization frame, which is usually a few seconds and no more than tens of seconds.

[0153] In a preferred embodiment of the present invention, the frame format is as follows: Figure 6 As shown:

[0154] 1) Between two adjacent rising edges, such as R0 and R1, R1 and R2..., T1 is measured by an internal high-frequency counter (accuracy of 10ns or higher);

[0155] 2) Starting from R1, send a synchronization frame (start frame), which includes a TRIG frame, a padding frame, and optionally a Report frame;

[0156] 3) The TRIG frame and Report frame are sent in the same direction as the software switching method. The TRIG frame carries T1 length information and is located in the data segment.

[0157] 4) The filling frame direction is S-TRG sent to R-TRG;

[0158] 5) The filling frame format is a CAN standard frame data frame. The size and data content of the filling frame data frame are calculated based on the total number of bits in the TRIG frame, the total number of bits in the Report frame, and the length of T1. This ensures that S-TRG completes T2 detection before the filling frame ends and that the total duration of the synchronization frame is always greater than the interval of a single synchronization pulse.

[0159] 6) The distinction between TRIG frames and padding frames can be achieved by adding identifiers to their respective data segments for R-TRG to differentiate and use;

[0160] 7) High-precision timing control logic: The frame interval is fixed at 3 bus bits, which conforms to the CAN bus standard. Arbitration is initiated immediately after the frame interval for any frame. Due to the higher priority, the arbitration result ensures that the bus is occupied.

[0161] 8) The R-TRG detects the first synchronization frame and determines it as the start frame. The identification method is the frame start level of the CAN standard frame on the bus. The R-TRG uses this to recover and generate the first pulse edge RC0. The delay of the pulse edge recovery is completely known (i.e., T1), which meets the synchronization requirements of the CT system.

[0162] 9) After the pulse edge is recovered by R-TRG, timing begins. At the same time, after receiving the complete TRIG frame, the duration of this T1 is known. Then, timing continues until T1, and the next pulse edge is recovered. R1 in the figure ensures that the pulse width length is consistent with the pulse detected by the S end.

[0163] 10) After the S-TRG finishes sending the padding frame, it initiates the next TRIG frame, carrying dT1 information, where dT1 is the time from R2 to the start of this TRIG frame transmission.

[0164] 11) After receiving the next TRIG frame, the R-TRG obtains T2 and dT1 information. At the same time, the R-TRG also times and obtains dTC1, which is the time when the RC1 receives this TRIG frame.

[0165] 12) The delay time TC2 generated by R-TRG is calculated as TC2 = T1 + dTC1 - dT1;

[0166] 13) The R-TRG timing starts from RC1 and continues until TC2 time has elapsed, then pulse RC2 is generated again;

[0167] 14) After receiving the TRIG frame, the R-TRG sends the Report frame and the padding frame in sequence;

[0168] 15) Repeat steps 9-13 above. The R-TRG will sequentially recover and generate subsequent pulses RCn (n>0). The delay time of RCn relative to RCn-1 is (precise time calculation delay):

[0169] TCn = TCn-1 + dTCn-1 -dTn-1;

[0170] in:

[0171] TCn-1 is the delay time of the pulse generated during the last recovery;

[0172] dTCn-1 represents the time from the last pulse generation to the start time of the current TRIG reception;

[0173] dTn-1 is the time from the most recent detection of the synchronization pulse to the start time of sending this TRIG frame, which is the S-TRG record and transmission obtained from the TRIG frame this time.

[0174] 16) Intelligent asynchronous time difference control: The relative time difference calculation adopted by the delay calculation time of the present invention ensures that the time measurement and recovery error of the two asynchronous clock systems S and R are always controlled on the measurement of dT (which is physically the time difference between the current time and the last time the synchronization pulse was detected), avoiding cumulative error and greatly improving the accuracy of synchronization pulse recovery.

[0175] One method for calculating padding frames in a frame format:

[0176] ①CT scans are usually set to a fixed rotation speed, such as 0.5s or 1s per revolution;

[0177] ② Taking 0.5 seconds as an example, each rotation generates 1500 angle measurements, which means 1500 synchronization pulses are generated per rotation. The time difference between two pulses is 0.5s / 1500=333us. The CAN bus transmission rate is 1Mbps, which means the transmission time for each data bit is 1us. Considering the actual slip ring measurement jitter and other errors, a maximum fault tolerance of 10% is taken, which means the maximum pulse width is 366us. Therefore, S-TRG ensures that from the detection of Rn to the end of the nth synchronization frame transmission is one calculation cycle, and one calculation cycle is always greater than 366us.

[0178] ③ Example of sending a synchronization frame:

[0179] 1) S-TRG transmission: TRIG frame, data segment is 6 bytes, frame interval is 3 data bits. Considering extreme bit padding, the total transmission time is between 95us and 114us.

[0180] 2) R-TRG transmission: Report frame, data segment is 2 bytes, frame interval is 3 data bits. Considering extreme bit padding, the total transmission time is between 60us and 75us.

[0181] 3) S-TRG transmission: padding frames, data segments are 0-8 bytes, frame interval of 3 data bits, approximately 50-120us;

[0182] 4) The duration of the padding frame of the previous synchronization frame in the current calculation cycle is assumed to be A;

[0183] 5) The minimum duration of this synchronization frame is B = 366 - A - 114 - 75, and we get B + A = 177us. Assuming A is a 60us fill frame, then B can be a 117us fill frame or two consecutive 60us fill frames.

[0184] 6) The number of bytes in a single padding frame of different durations can be adjusted according to actual needs by changing the number of data segments transmitted. Usually, this method is sufficient to meet the padding requirements.

[0185] 7) The number of bit padding operations can also be controlled by adjusting the data format of the data segment to achieve more precise padding time at the microsecond level;

[0186] ④ For synchronization pulses with longer time differences, such as lower speeds or fewer pulses per revolution, more fill frames can be added as needed;

[0187] ⑤ For synchronization pulses with shorter time differences, such as higher rotation speeds or fewer pulses per revolution, if necessary, a higher transmission rate can be considered, such as 2 Mbps, or the use of a higher-speed CAN-FD protocol.

[0188] Example 3

[0189] A third aspect of the present invention provides a single-track data transmission method, applied to a single-track data transmission system, comprising the following steps:

[0190] A CAN bus-based communication network is established on a single pair of slip ring differential transmission lines, with all nodes connected via CAN transceivers.

[0191] Control command data and trigger synchronization data are transmitted simultaneously on the same pair of differential lines using multiplexing.

[0192] During TRIG transmission, the clocks of the STRG and RTRG nodes are kept synchronized to ensure that the transmission is not interrupted during a continuous data acquisition or exposure process;

[0193] The encoder edge is recovered based on the received timestamp information, which is used to trigger the data acquisition system.

[0194] According to an embodiment of the present invention, the switching conditions for mode switching include one of receiving a frame identifier of the TRIG protocol, triggering a timeout mechanism, and receiving a manual switching instruction.

[0195] In summary, by flexibly switching between CAN and TRIG communication through multiplexing, and flexibly switching communication protocols, information exchange between application software is facilitated. During CT scanning, the data collected by the detector is synchronized with information such as the angle of the gantry and the position of the scanning bed, improving the accuracy of the collected data, maximizing compatibility with standard CAN networks, and balancing real-time performance and flexibility.

[0196] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0197] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to the above embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0198] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A single-track data transmission system, characterized in that, include: A pair of slip ring differential transmission lines serve as the only available physical data transmission channel for the CT scanning system; The stationary end control unit includes a synchronization information acquisition module, an S controller, and an S-TRG communication node. The S controller includes at least one standard CAN node, S-CAN. The rotating end control unit includes a data acquisition system, an R controller, and an R-TRG communication node. The R controller includes at least one standard CAN node, R-CAN. The S-TRG communication node and the R-TRG communication node are connected to the slip ring differential transmission line via a CAN transceiver to form a CAN bus network; S-TRG communication nodes and S-CAN communication nodes are interconnected via SPI or serial port. R-TRG communication nodes and R-CAN communication nodes are interconnected via SPI or serial port. The system is configured to simultaneously transmit control command data and trigger synchronization data on the single slide rail via multiplexing.

2. The single-track data transmission system according to claim 1, characterized in that, The reuse method includes a first method and a second method; The first method is software-controlled reuse, which switches between CAN communication mode and TRIG communication mode through software processes; The second method is adaptive switching multiplexing, which automatically switches between CAN communication and TRIG communication based on bus status and transmission requirements; During TRIG communication, the S-TRG and R-TRG nodes remain synchronized; In CAN communication mode, the scanning system mainly transmits parameter configuration and system status information; In TRIG communication mode, the scanning system transmits time and space synchronization information.

3. The single-track data transmission system according to claim 2, characterized in that, The reuse of software control includes: The system sets bus status indicators, including CAN communication status and TRIG communication status; The master node controls the state switching, and the other nodes determine their own behavior based on the state flag. In CAN communication mode, only standard CAN nodes are allowed to communicate, using the standard CAN data link layer protocol; In TRIG communication mode, only S-TRG and R-TRG nodes are allowed to communicate, using a trigger synchronization protocol based on CAN frame format; The triggering conditions for switching from TRIG communication state to CAN communication state include: receiving the end marker of the TRIG protocol, triggering the timeout mechanism, or a command from the master node.

4. The single-track data transmission system according to claim 3, characterized in that, The adaptive switching multiplexing includes: S-TRG and R-TRG nodes can autonomously occupy the bus without software intervention for mode switching; By controlling the frame interval, it is ensured that the bus occupancy-idle-arbitration state defined by the standard CAN protocol is met during TRIG transmission, and that S-TRG and R-TRG repeatedly initiate transmission arbitration at the first time. By setting the highest S-TRG and R-TRG node priorities, it is ensured that the node can successfully and continuously obtain bus access after initiating arbitration; After completing the TRIG data transmission, the bus control is automatically released, allowing the bus to resume standard CAN communication.

5. A single-channel transmission CT system, applied to the single-track data transmission system according to any one of claims 1-4, characterized in that, include: CT scanning system, including a single-track data transmission system; Scanning support, including slip rings and image chain components; The imaging chain components include an X-ray tube, a high-voltage generator, and a detector; The slip ring is connected to a CAN transceiver; A patient stent, which is connected to a slip ring.

6. A single-track data transmission method, applied to the single-track data transmission system according to any one of claims 1-4, characterized in that, Includes the following steps: A CAN bus-based communication network is established on a single pair of slip ring differential transmission lines, with all nodes connected via CAN transceivers. Control command data and trigger synchronization data are transmitted simultaneously on the same pair of differential lines using multiplexing. During TRIG transmission, the clocks of the STRG and RTRG nodes are kept synchronized to ensure that the transmission is not interrupted during a continuous data acquisition or exposure process; The encoder edge is recovered based on the received timestamp information, which is used to trigger the data acquisition system.

7. The single-track data transmission method according to claim 6, characterized in that, in, The switching conditions for mode switching include receiving a frame identifier from the TRIG protocol, triggering a timeout mechanism, or receiving a manual switching command.

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