Industrial wireless remote controller, industrial control system and wireless communication method thereof
Patent Information
- Application Number
- CN202510327582.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-19
- Publication Date
- 2026-09-22
AI Technical Summary
[0003]目前，工业无线遥控器一般采用固定频率通信，该方式对于环境干扰的抵抗能力较弱，容易导致信号的不稳定性和丢包率过高，影响工业被控设备的控制精度和实时响应
[0015]上述技术方案中的一个技术方案具有如下优点或有益效果：采用上述工业无线控制器进行工业控制的过程中，发射模块检测到接收模块根据对频包反馈的对频应答包后，可向接收模块发送同步请求，同步请求中至少携带有预定义频率数量、每个预定义频率的通信时长、跳频周期及跳频序列，以与接收模块协商跳频通信模式；本方法利用跳频技术使得工业无线控制器与工业被控设备之间通讯，可有效降低外界干扰，提高工业控制稳定性。
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Figure CN122799604A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of industrial control technology, and in particular to an industrial wireless remote controller, an industrial control system and a wireless communication method thereof. Background Technology
[0002] An industrial wireless remote controller is a device used for remote wireless control of industrial machinery or equipment. It is widely used in metallurgy, shipbuilding, container terminals, warehousing, machinery manufacturing, chemical industry, papermaking, construction, fire protection, and engineering machinery. It mainly transmits control commands through radio signals to achieve remote operation, reduce direct human intervention, and reduce the occurrence of dangerous situations.
[0003] Currently, industrial wireless remote controllers generally use fixed-frequency communication. This method is less resistant to environmental interference, which can easily lead to signal instability and high packet loss rate, affecting the control accuracy and real-time response of industrial controlled equipment. Summary of the Invention
[0004] Therefore, it is necessary to provide an industrial wireless remote controller, an industrial control system, and a wireless communication method thereof to address the aforementioned technical problems.
[0005] In a first aspect, this application provides an industrial wireless remote controller, including a transmitting module configured to: transmit a frequency pairing packet; detect a frequency pairing response packet fed back by a receiving module based on the frequency pairing packet, and send a synchronization request to the receiving module; the synchronization request carries at least a predefined number of frequencies, the communication duration of each predefined frequency, a frequency hopping period, and a frequency hopping sequence, for negotiating a frequency hopping communication mode with the receiving module; detect an acknowledgment signal fed back by the receiving module based on the synchronization request, and communicate with the receiving module according to the negotiated frequency hopping communication mode.
[0006] In one embodiment, the frequency hopping communication mode includes automatically hopping to the next predefined frequency when the dwell time of the current predefined frequency reaches the communication time of the predefined frequency.
[0007] In one embodiment, the industrial wireless remote controller further includes the receiving module, the synchronization request carrying a first timestamp when the synchronization request was sent, and the acknowledgment signal carrying a second timestamp when the receiving module received the synchronization request and a third timestamp when the acknowledgment signal was sent; the transmitting module is further configured to: determine a fourth timestamp when the acknowledgment signal was received; calculate an initial clock offset between the transmitting module and the receiving module based on the first timestamp, the second timestamp, the third timestamp, and the fourth timestamp; and align the initial clocks of the transmitting module and the receiving module based on the initial clock offset.
[0008] In one embodiment, one of the transmitting module and the receiving module is further configured to: periodically embed a local timestamp into the data packet to be transmitted, in the case of initial clock alignment; the other of the receiving module and the transmitting module is further configured to: receive the data packet to be transmitted and identify the local timestamp; calculate the current time difference based on the local timestamp and the current timestamp when the data packet is received; and, in response to the current time difference being greater than a set threshold, calculate the current clock deviation between the transmitting module and the receiving module by exchanging timestamps, and perform clock alignment based on the current clock deviation.
[0009] In one embodiment, the other of the receiving module and the transmitting module is further configured to: acquire at least one recent historical clock deviation; calculate a cumulative deviation, the cumulative deviation being the sum of the current clock deviation and the at least one historical clock deviation; calculate a time correction, the time correction including the sum of the product of the current clock deviation and a scaling factor, and the product of the cumulative deviation and an integral factor, wherein the scaling factor and the integral factor are both determined based on the magnitude of the current clock deviation; and correct the local clock based on the time correction.
[0010] In one embodiment, the transmitting module is further configured to: if the number of times clock alignment failure with the receiving module is detected reaches a first preset value, switch to the next backup channel to renegotiate communication with the receiving module; if the number of times renegotiation failure is detected reaches a second preset value, report a system abnormality.
[0011] In one embodiment, the receiving module is further configured to: send the signal strength value and packet loss rate value of the current channel to the transmitting module; the transmitting module is further configured to: determine whether the signal strength value and the packet loss rate value are normal; if both values are normal, normalize them respectively, and use the processing results as the score of the signal strength index and the score of the packet loss rate index; if there is an abnormal value, assign the score of the corresponding index to 0; calculate the quality score of the current channel; the quality score is the sum of the product of the signal strength index score and the first weight, and the product of the packet loss rate index score and the second weight, wherein the sum of the first weight and the second weight is 1; in response to the quality score being less than the standard score, switch to the next backup channel and renegotiate communication with the receiving module.
[0012] In one embodiment, the transmitting module is further configured to: determine the ratio of the difference between the signal strength value and the strength standard value to the difference between 0 and the strength standard value, as a score of the signal strength index; and / or determine the difference between 1 and the ratio of the packet loss rate value and the packet loss rate threshold, as a score of the packet loss rate index.
[0013] Secondly, this application also provides an industrial control system, including an industrial controlled device and the aforementioned industrial wireless remote controller. The industrial wireless remote controller includes the receiving module and an actuator signal-connected to the receiving module. The actuator is configured to be connected to the industrial controlled device.
[0014] Thirdly, this application also provides a wireless communication method applied to the transmitting module of an industrial wireless remote controller, comprising: transmitting a frequency pairing packet; detecting that the receiving module sends a synchronization request to the receiving module based on the frequency pairing response packet fed back by the frequency pairing packet; the synchronization request carrying at least a predefined number of frequencies, the communication duration of each predefined frequency, the frequency hopping period, and the frequency hopping sequence, for negotiating a frequency hopping communication mode with the receiving module; detecting that the receiving module communicates with the receiving module according to the negotiated frequency hopping communication mode based on the confirmation signal fed back by the synchronization request.
[0015] One of the above technical solutions has the following advantages or beneficial effects: During industrial control using the above-mentioned industrial wireless controller, after the transmitting module detects the frequency matching response packet fed back by the receiving module according to the frequency matching packet, it can send a synchronization request to the receiving module. The synchronization request carries at least the number of predefined frequencies, the communication duration of each predefined frequency, the frequency hopping period, and the frequency hopping sequence to negotiate the frequency hopping communication mode with the receiving module. This method uses frequency hopping technology to enable communication between the industrial wireless controller and the industrial controlled equipment, which can effectively reduce external interference and improve the stability of industrial control. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the structure of an industrial wireless remote controller in one embodiment;
[0017] Figure 2 This is a flowchart of a method for connecting a transmitting module and a receiving module in one embodiment;
[0018] Figure 3 This is a schematic diagram of a frequency hopping sequence in one embodiment;
[0019] Figure 4 This is a flowchart illustrating a clock alignment method for the transmitting module and the receiving module in one embodiment;
[0020] Figure 5 This is a flowchart illustrating the current channel quality assessment method in one embodiment;
[0021] Figure 6 This is a schematic diagram of the structure of an industrial control system in one embodiment. Detailed Implementation
[0022] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0023] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0024] by Figures 1 to 5 Taking an example, this application provides an industrial wireless remote controller and its wireless communication method, which will be described and introduced accordingly. The industrial wireless remote controller provided in this application includes a transmitting module, such as... Figure 1 As shown, the transmission module is configured as follows:
[0025] S102, send frequency pairing packet.
[0026] The transmitting module can send frequency-hopping packets (or frequency-hopping frames) via frequency hopping. It can also scan multiple fixed channels and switch between them at fixed time intervals. These fixed time intervals can be set consistently, for example, 50ms each. The transmitting module can attempt communication on each channel, and if the receiving module does not respond within the fixed time interval, the transmitting module can automatically switch to the next channel.
[0027] S104, it is detected that the receiving module sends a synchronization request to the receiving module based on the frequency matching response packet fed back by the frequency matching packet; the synchronization request carries at least the number of predefined frequencies, the communication duration of each predefined frequency, the frequency hopping period and the frequency hopping sequence, in order to negotiate the frequency hopping communication mode with the receiving module.
[0028] Frequency packets may carry preambles, such as Figure 2 As shown, after receiving the frequency pairing packet, the receiving module can achieve time and frequency synchronization with the transmitting module by recognizing a specific sequence in its preamble. That is, the preamble in the frequency pairing packet can be used for coarse synchronization between the receiving and transmitting modules. Of course, the preamble can also carry other sequences or fields to facilitate correct demodulation of data fields by the receiving module, ensuring system transmission performance.
[0029] After the receiving module detects and successfully receives the frequency pairing packet from the transmitting module, it can send a frequency pairing response packet back to the transmitting module. In response to the detection of the frequency pairing response packet, the transmitting module can send a synchronization request to the receiving module. This synchronization request can be understood as one or more synchronization frames. By sending one or more synchronization frames, the transmitting module attempts to establish synchronization with the receiving module.
[0030] The number of predefined frequencies can be understood as the total number of available frequencies pre-set in a frequency-hopping communication system. For example, if there are 100 frequencies, the system will switch between these frequencies. The communication duration for each predefined frequency can be understood as the time the system stays or resides on each predefined frequency during the frequency hopping process. The frequency hopping period can be understood as the time required for the system to complete one full frequency hopping sequence and return to the starting frequency. For example, if the system switches between 10 frequencies, staying on each frequency for 1 millisecond, the frequency hopping period is 10 milliseconds. The frequency hopping sequence can be understood as a list of frequencies that the system switches in a specific order during the frequency hopping process; this sequence can be a fixed sequence or a pseudo-random sequence.
[0031] By including at least the number of predefined frequencies, the communication duration of each predefined frequency, the frequency hopping period, and the frequency hopping sequence in the synchronization request, the frequency hopping communication mode can be negotiated with the receiving module.
[0032] S106, the acknowledgment signal fed back by the receiving module according to the synchronization request is detected, and communication with the receiving module is carried out in accordance with the agreed frequency hopping communication mode.
[0033] The receiving module sends an acknowledgment signal (ACK) upon receiving the synchronization request, indicating that the receiving module and the transmitting module have successfully synchronized through the synchronization request and can then perform frequency hopping communication using the same frequency hopping communication mode. Upon receiving the ACK signal, the transmitting module confirms the successful connection and proceeds to the subsequent frequency hopping communication phase.
[0034] In one or more embodiments, the frequency hopping communication mode may include automatically hopping to the next predefined frequency if the dwell time of the current predefined frequency reaches the communication time of the predefined frequency.
[0035] After the transmitting and receiving modules are successfully connected, the transmitting and receiving parties have agreed to use a predefined number of frequencies for subsequent communication. Figure 3A set of frequencies (e.g., f1, f2, f3, f4…) is shown, which can serve as a negotiated frequency hopping sequence. For further optimization, the communication duration T for each predefined frequency can be set consistently, for example, T = 100ms. The automatic hopping to the next predefined frequency after the dwell time on the current predefined frequency reaches the communication duration T can be understood in three scenarios: First, when both parties successfully transmit data on the current predefined frequency, after a normal communication period T, the system automatically hops to the next predefined frequency; second, when data transmission on the current predefined frequency times out or fails (e.g., due to channel interference), the system will still force a switch to the next predefined frequency to avoid stagnation due to waiting; third, when the current channel is idle and there is no data transmission, the system will still automatically hop to the next predefined frequency after the dwell time T on the current predefined frequency. This mechanism effectively improves the overall communication's anti-interference capability and stealth through forced periodic frequency hopping and timeout switching strategies. Combined with a short dwell time and pseudo-random sequence communication mechanism, it significantly reduces the probability of being blocked across the entire frequency band.
[0036] In one or more embodiments, the industrial wireless remote controller further includes a receiving module, wherein the synchronization request carries a first timestamp when the synchronization request is sent, and the acknowledgment signal carries a second timestamp when the receiving module receives the synchronization request and a third timestamp when the acknowledgment signal is sent; the transmitting module is further configured to: determine a fourth timestamp when the acknowledgment signal is received; calculate an initial clock offset between the transmitting module and the receiving module based on the first timestamp, the second timestamp, the third timestamp, and the fourth timestamp; and align the initial clocks of the transmitting module and the receiving module based on the initial clock offset.
[0037] The aforementioned time synchronization mechanism achieves more precise initial time synchronization through the first information exchange between the transmitting and receiving modules. It can be used in conjunction with the coarse synchronization of the aforementioned preamble; that is, coarse synchronization is performed during the initial non-working phase, followed by initial fine synchronization during the working interaction phase. This dual-mode synchronization mechanism, combining coarse and fine synchronization, ensures precise time synchronization between the transmitting and receiving modules, guaranteeing smooth and accurate subsequent communication. It should be noted that all the timestamps mentioned above can be recorded using a local high-precision clock (such as a hardware timer).
[0038] In one specific implementation, the transmitting module first sends a synchronization request, carrying the current transmission timestamp T1 (i.e., the first timestamp). Upon receiving this request, the receiving module records its reception time T2 (i.e., the second timestamp). Subsequently, the receiving module returns information in the form of an acknowledgment, carrying its received timestamp T2 and its own transmission timestamp T3 (i.e., the third timestamp). Upon receiving the acknowledgment, the transmitting module records the timestamp T4 (i.e., the fourth timestamp). Based on these timestamps, assuming the delay d1 from transmission to reception is equal to the delay d2 from reception to transmission (d1 = d2), the transmitting module can calculate the initial clock deviation as θ = [(T2 - T1) + (T3 - T4)] / 2; where T2 - T1 can be understood as the time from transmission to reception of the synchronization request (including deviation and delay); T3 - T4 can be understood as the time difference between reception and transmission of the acknowledgment signal (including delay and deviation); under the assumption of symmetrical transmission delay, the deviation is eliminated by averaging the two one-way time differences.
[0039] Then, the transmitting module can adjust its local clock according to θ. The specific adjustment strategy can be as follows:
[0040] If θ > 0, it can be understood that the transmitting module's clock is slower than the receiving module's clock by θ, and the local time needs to be increased by θ. If θ < 0, it can be understood that the transmitting module's clock is faster, and the corresponding time needs to be decreased. Alternatively, software compensation can be used to dynamically add the deviation value to the time calculation.
[0041] Furthermore, to improve accuracy, this scheme can perform multiple synchronous measurements based on the original scheme to calculate the average θ, thereby eliminating the quantization error of a single measurement; or use moving average (MA), exponentially weighted moving average (EWMA), or Kalman filter to dynamically smooth the θ value to obtain a more accurate θ estimate; or introduce a correction coefficient β to eliminate quantization error and ensure more accurate subsequent time synchronization. A specific implementation scheme could be: if the transmission delay is asymmetrical (d1≠d2), introduce a correction coefficient β (the ratio of uplink to downlink delay, i.e., β=d1 / d2) to adjust the above formula, i.e.:
[0042] θ = [(T2-T1)-β*(T3-T4)] / (1+β). Where β can be determined experimentally or by known link characteristics.
[0043] In one or more embodiments, such as Figure 4As shown, one of the transmitting module and the receiving module is further configured to: periodically embed a local timestamp into the data packet to be transmitted under initial clock alignment; the other of the receiving module and the transmitting module is further configured to: receive the data packet to be transmitted and identify the local timestamp; calculate the current time difference based on the local timestamp and the current timestamp when the data packet is received; and, in response to the current time difference being greater than a set threshold, calculate the current clock deviation between the transmitting module and the receiving module by exchanging timestamps, and perform clock alignment based on the current clock deviation.
[0044] The data packets to be sent refer to the data packets that the receiving and transmitting modules need to send during normal communication under the initial clock alignment. It should be noted that both the transmitting and receiving modules can periodically embed their local timestamps into the data packets to be sent to enable clock alignment between them; it is not necessarily limited to one of them. The method and principle for calculating the current clock deviation between the transmitting and receiving modules by exchanging timestamps are equivalent to those used in the initial clock alignment process described above, where the initial clock deviation between the transmitting and receiving modules is calculated based on the first, second, third, and fourth timestamps. The current clock deviation can also be calculated by introducing a correction coefficient β to eliminate quantization errors from a single measurement; the principle is explained above and will not be repeated here.
[0045] Periodic time synchronization and correction ensure that the transmitting and receiving modules send and receive data at the correct time, preventing data loss or errors due to time discrepancies. This allows multiple industrial wireless remote controllers to synchronously control the same industrial device, and a single industrial wireless remote controller to synchronously and accurately control multiple industrial devices. This facilitates the deployment of industrial wireless remote controllers in high-precision, coordinated industrial scenarios, enabling the execution of complex industrial control tasks. Furthermore, periodic time synchronization and correction allow the transmitting and receiving modules to utilize spectrum resources more efficiently, facilitating coordinated communication even in complex industrial control scenarios, avoiding packet collisions, and reducing interference. Simultaneously, periodic time synchronization enhances the security of industrial control system communication, preventing unauthorized access by industrial wireless remote controllers or industrial devices. This robust synchronization mechanism helps personnel promptly locate and address security risks in industrial devices or the entire industrial control system, improving industrial safety. In summary, periodic time synchronization significantly improves the control accuracy of industrial wireless remote controllers, the reliability and resource utilization of industrial control systems, supports complex control strategies, enhances security, and simplifies system integration; these advantages make industrial control systems more efficient, reliable, and secure.
[0046] In one or more embodiments, further reference may be made. Figure 4The other of the receiving module and the transmitting module is further configured to: acquire at least one recent historical clock deviation; calculate the cumulative deviation; the cumulative deviation is the sum of the current clock deviation and at least one historical clock deviation; calculate the time correction; the time correction includes the sum of the product of the current clock deviation and the proportional coefficient, and the product of the cumulative deviation and the integral coefficient, wherein the proportional coefficient and the integral coefficient are both determined based on the magnitude of the current clock deviation; and correct the local clock based on the time correction.
[0047] It should be explained that historical clock skew can be understood as the clock skew between the transmitting and receiving modules calculated at a certain point in the past; the most recent historical clock skew can be understood as one or more recent historical skew data points, the specific number depending on the system design, it could be the most recent one, or it could be several recent ones, there is no limit here. The most recent historical clock skew can be obtained by retrieving it from local memory, and used to calculate the cumulative skew, which is the sum of the current clock skew and all acquired historical clock skews.
[0048] In this embodiment, to address the clock drift issue, a dynamic PI (proportional-integral) control algorithm can be implemented to adjust the clock frequency. This algorithm evaluates and dynamically adjusts the clock frequency in real time based on the accumulated error, ensuring precise time synchronization between the transmitting and receiving modules. The specific principle can be found in the following formula:
[0049] u(t) = K p ·e(t)+K i ·∫e(t)dt, where u(t) is the time correction amount, K p K is the proportionality coefficient. i Let be the integral coefficient, e(t) be the current clock offset, and ∫e(t) be the cumulative offset. The above scheme can be understood as... Figure 4 This is a method of adjusting the time in a small, proportional manner to avoid sudden changes.
[0050] In addition to the aforementioned periodic triggering of time synchronization, in some embodiments, synchronization can also be triggered by an error threshold. Specifically, by setting an error threshold and a resynchronization mechanism, the accuracy of time synchronization can be ensured to always be within the set error threshold (e.g., ±0.1 milliseconds) to maintain the accuracy of synchronization.
[0051] In one or more embodiments, the transmitting module is further configured to: if the number of times clock alignment failure with the receiving module is detected reaches a first preset value, switch to the next backup channel to renegotiate communication with the receiving module; if the number of times renegotiation failure is detected reaches a second preset value, report a system abnormality.
[0052] To enhance system reliability, this embodiment is configured with an anomaly handling strategy. After synchronization fails for a first set value (e.g., 2 times), the system can automatically enter a renegotiation mode. Furthermore, the maximum number of retries can be set to a second set value (e.g., 3 times). If synchronization still cannot be completed after retries, a system anomaly is reported to attract the attention of staff and enable real-time monitoring.
[0053] In one or more embodiments, such as Figure 5 As shown, the receiving module is further configured to: send the signal strength value and packet loss rate value of the current channel to the transmitting module; the transmitting module is further configured to: determine whether the signal strength value and packet loss rate value are normal; if both values are normal, normalize them respectively, and use the processing results as the score of the signal strength index and the score of the packet loss rate index; if there is an abnormal value, assign the score of the corresponding index to 0; calculate the quality score of the current channel; the quality score is the sum of the product of the signal strength index score and the first weight, and the product of the packet loss rate index score and the second weight, the sum of the first weight and the second weight is 1; in response to the quality score being less than the standard score, switch to the next backup channel and renegotiate communication with the receiving module. In one or more embodiments, the transmitting module is further configured to: determine the ratio of the difference between the signal strength value and the strength standard value to the difference between 0 and the strength standard value, as the score of the signal strength index; and / or, determine the difference between 1 and the ratio of the packet loss rate value and the packet loss rate threshold, as the score of the packet loss rate index.
[0054] In this embodiment, the transmitting and receiving modules of the industrial wireless remote controller also have path quality assessment capabilities. Specifically, the receiving module monitors the signal strength and packet loss rate of the current channel in real time or periodically, and dynamically switches to the next backup channel based on the assessment results to ensure communication quality. The main objective of this path quality assessment algorithm is to dynamically determine the quality of the communication path by evaluating the signal strength (RSSI) and packet loss rate of the wireless communication path, thereby deciding whether to switch to a backup path to ensure the communication reliability and stability of the industrial wireless remote control system. The effectiveness of this algorithm can improve the performance of the industrial wireless remote controller in complex and interference environments.
[0055] Combination Figure 5 The implementation process of this path quality assessment algorithm mainly includes the following steps:
[0056] First, the receiving module can periodically or in real-time collect data from the current communication path. This data may include RSSI values and packet loss rate. RSSI directly characterizes signal strength and stability, while packet loss rate is a key indicator of network communication reliability. When measuring the RSSI value of the available path, the receiving module amplifies the received signal using a low-noise amplifier, down-converts it to an intermediate frequency using a mixer, removes out-of-band noise and interference using a bandpass filter, converts the filtered signal to a digital signal using an ADC, and then calculates the RSSI value based on signal power or amplitude. When measuring the packet loss rate of the available path, the receiving module can count the total number of data packets sent and the number of successfully received data packets, and then use the following formula:
[0057] Packet loss rate = (Total number of data packets sent - Number of data packets successfully received) / Total number of data packets sent × 100%, calculate the packet loss rate.
[0058] Secondly, the receiving module can determine whether the measured RSSI value is valid. If the RSSI value is outside a reasonable range, the system will consider this path unreliable and set the path score to 0 to reflect the actual quality degradation. If the detected RSSI value is valid, it needs to be normalized. The normalization calculation can be performed according to the following formula:
[0059] RSSI score = [RSSI - (-80)] / [0 - (-80)], where -80dBm is the standard strength value used as an example, and can be set according to actual conditions. After mapping, the RSSI value has a score range of [0, 1], and a higher score indicates better signal quality.
[0060] Meanwhile, the receiving module can determine whether the statistically measured packet loss rate is within the normal range. If the packet loss rate exceeds the set packet loss rate threshold, the packet loss rate score of the path is set to 0, indicating that the path quality is unqualified. For normal packet loss rates, the system performs normalization processing, which can be calculated using the following formula:
[0061] Packet loss rate score = 1 - packet loss rate / packet loss rate threshold, to map the result to the interval [0, 1]. The packet loss rate threshold can be set according to the actual situation, for example, 10%.
[0062] Secondly, after normalization, the receiving module can convert the RSSI and packet loss rate scores according to the set weights. The weights can be set to fixed values, for example, RSSI weight set to 0.6 and packet loss rate weight set to 0.4, to calculate their contribution to path quality.
[0063] Then, through weighted calculation, the overall quality score of the path is obtained. The calculation formula is as follows:
[0064] Path quality score = (RSSI score × 0.6) + (packet loss rate score × 0.4). The overall score range is also [0, 1]. The higher the score, the better the path quality.
[0065] Finally, the receiving module compares the overall path quality score with a pre-set standard score (e.g., 0.3) to determine whether the current path meets the standard. If the measured path quality meets the standard, the system will continue to use this path and maintain monitoring, periodically reassessing the path quality. If the path quality does not meet the standard, the system will initiate a path switching mechanism to select an alternative path for communication.
[0066] In some embodiments, during path switching, the receiving module can select a higher-quality path from a preset pool of candidate paths to ensure communication stability and continuity. The higher-quality path can be determined based on historical scores of each backup path, or by periodically evaluating path quality and dynamically selecting the optimal path. Alternatively, multiple paths can be used simultaneously for data transmission, with the highest-quality path selected as the primary path. If the quality of the switched path deteriorates, the receiving module can quickly revert to the previous path or select another candidate path. Path switching can be achieved by updating the routing table or path configuration and notifying the sending end to switch to the selected path.
[0067] By employing the aforementioned industrial wireless controller and utilizing frequency hopping technology for communication with industrial controlled equipment, external interference can be effectively reduced, and communication stability improved. Simultaneously, the fast connection algorithm and high-precision time synchronization mechanism enable the industrial wireless controller to respond quickly, contributing to enhanced real-time control capabilities of the equipment. Furthermore, the use of a path quality assessment algorithm enhances the reliability of the industrial wireless controller's communication process; this path quality assessment optimizes the signal transmission path and reduces data loss rate.
[0068] On the other hand, see Figure 6 This application also proposes an industrial control system, including an industrial controlled device and the aforementioned industrial wireless remote controller. The industrial wireless remote controller includes a receiving module and an actuator that is signal-connected to the receiving module. The actuator is configured to be connected to the industrial controlled device.
[0069] In some embodiments, multiple industrial wireless remote controllers in an industrial control system can synchronously control the same industrial controlled device, and a single industrial wireless remote controller can also synchronously and accurately control multiple industrial controlled devices; the transmitting module of a single industrial wireless remote controller can correspond to multiple receiving modules, which can be configured on the same industrial controlled device or on different industrial controlled devices.
[0070] By configuring the aforementioned industrial control system, multiple industrial wireless remote controllers can synchronously control the same industrial controlled device, and a single industrial wireless remote controller can also synchronously and precisely control multiple industrial controlled devices. This facilitates the deployment of industrial wireless remote controllers in high-precision, coordinated industrial scenarios to perform complex industrial control tasks. Furthermore, through periodic time synchronization and correction, the transmitting and receiving modules can utilize spectrum resources more efficiently. Even in complex industrial control scenarios, this helps coordinate communication, avoid packet collisions, and reduce interference. Simultaneously, periodic time synchronization enhances the security of industrial control system communication, preventing unauthorized access by industrial wireless remote controllers or industrial controlled devices. This robust synchronization mechanism helps personnel promptly locate and address security risks in industrial controlled devices or the entire industrial control system, improving industrial safety. By employing a path quality assessment algorithm, the communication reliability of the industrial control system is enhanced, signal transmission paths are optimized, and data loss rates are reduced.
[0071] In summary, the aforementioned industrial control systems offer high control precision, reliability, and resource utilization, support complex control strategies, strong security, and are more efficient, reliable, and safe in operation.
[0072] Obviously, the above embodiments of this application are merely examples for clear illustration and are not intended to limit the implementation of this application. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of the claims of this application.
Claims
1. An industrial wireless remote control, characterized in that, Includes a transmission module, which is configured to: Send frequency pairing packets; The receiving module is detected to send a synchronization request to the receiving module based on the frequency matching response packet fed back by the frequency matching packet; the synchronization request carries at least the number of predefined frequencies, the communication duration of each predefined frequency, the frequency hopping period and the frequency hopping sequence, in order to negotiate the frequency hopping communication mode with the receiving module; Upon detecting the confirmation signal fed back by the receiving module according to the synchronization request, communication is initiated with the receiving module in accordance with the agreed frequency hopping communication mode.
2. The industrial wireless remote controller according to claim 1, characterized in that, The frequency hopping communication mode includes automatically hopping to the next predefined frequency when the dwell time of the current predefined frequency reaches the communication time of that predefined frequency.
3. The industrial wireless remote controller according to claim 1, characterized in that, The industrial wireless remote controller also includes the receiving module, and the synchronization request carries a first timestamp when the synchronization request is sent, and the confirmation signal carries a second timestamp when the receiving module receives the synchronization request and a third timestamp when the confirmation signal is sent. The transmitting module is also configured to: Determine the fourth timestamp when the confirmation signal is received; Calculate the initial clock offset between the transmitting module and the receiving module based on the first timestamp, the second timestamp, the third timestamp, and the fourth timestamp; The initial clocks of the transmitting module and the receiving module are aligned based on the initial clock offset.
4. The industrial wireless remote controller according to claim 3, characterized in that, One of the transmitting module and the receiving module is further configured to periodically embed a local timestamp into the data packet to be transmitted, provided that the initial clock is aligned. The other of the receiving module and the transmitting module is further configured to: Receive the data packet to be sent and identify the local timestamp; The current time difference is calculated based on the local timestamp and the current timestamp when the data packet was received; In response to the current time difference being greater than a set threshold, the current clock deviation between the transmitting module and the receiving module is calculated by exchanging timestamps, and clock alignment is performed based on the current clock deviation.
5. The industrial wireless remote controller according to claim 4, characterized in that, The other of the receiving module and the transmitting module is further configured to: Obtain at least one recent historical clock skew value; Calculate the cumulative deviation; the cumulative deviation is the sum of the current clock deviation and the at least one historical clock deviation; Calculate the time correction amount; the time correction amount includes the sum of the product of the current clock deviation and the proportional coefficient, and the product of the cumulative deviation and the integral coefficient, wherein the proportional coefficient and the integral coefficient are both determined based on the magnitude of the current clock deviation; The local clock is corrected according to the time correction amount.
6. The industrial wireless remote controller according to claim 4, characterized in that, The transmitting module is also configured to: If the number of times the clock alignment failure with the receiving module is detected reaches a first set value, switch to the next backup channel and renegotiate communication with the receiving module. If the number of failed renegotiations reaches the second preset value, a system error will be reported.
7. The industrial wireless remote controller according to any one of claims 3-6, characterized in that, The receiving module is also configured to send the current channel signal strength value and packet loss rate value to the transmitting module; The transmitting module is also configured to: Determine whether the signal strength value and the packet loss rate value are normal; If both values are normal, normalize them separately and use the results as the scores for signal strength and packet loss rate. If there are numerical anomalies, the score of the corresponding indicator will be set to 0; Calculate the quality score of the current channel; the quality score is the sum of the product of the signal strength index score and the first weight, and the product of the packet loss rate index score and the second weight, wherein the sum of the first weight and the second weight is 1; In response to the quality score being less than the standard score, the system switches to the next backup channel to renegotiate communication with the receiving module.
8. The industrial wireless remote controller according to claim 7, characterized in that, The transmitting module is also configured to: The ratio of the difference between the numerical signal strength value and the standard strength value to the difference between 0 and the standard strength value is determined as the score of the signal strength index; And / or, determine the difference between 1 and the ratio of the packet loss rate value and the packet loss rate threshold, as the score of the packet loss rate index.
9. An industrial control system, characterized in that, The invention includes an industrial controlled device and an industrial wireless remote controller as described in any one of claims 1-8, wherein the industrial wireless remote controller includes the receiving module and an actuator signal-connected to the receiving module, and the actuator is configured to be connected to the industrial controlled device.
10. A wireless communication method applied to the transmitting module of an industrial wireless remote controller, comprising: Send frequency pairing packets; The receiver module sends a synchronization request to the receiver module based on the frequency matching response packet fed back by the frequency matching packet; The synchronization request carries at least the number of predefined frequencies, the communication duration of each predefined frequency, the frequency hopping period, and the frequency hopping sequence, in order to negotiate the frequency hopping communication mode with the receiving module. Upon detecting the confirmation signal fed back by the receiving module according to the synchronization request, communication is initiated with the receiving module in accordance with the agreed frequency hopping communication mode.