Temperature-salt profile agile observation data acquisition and processing system

Abstract

The invention discloses a thermohaline profile agile observation data acquisition and processing system. The system comprises a master control and timing module, a sensor communication and acquisition module, a data processing and storage module, a satellite positioning module, a satellite data transmission module and a power supply and protection module. The system adopts a time slot type working sequence, and performs sensor preheating, data acquisition and turn-off dormancy in a time-sharing manner so as to reduce average power consumption and suppress cold start drift; in multi-channel acquisition, zero setting and bit keeping are carried out on unanswered channels based on RS-485 / Modbus polling, statistical averaging is carried out on multiple rounds of samples in the same acquisition period, and then storage is carried out, so that missing measurement is explicitly presented while the channel sequence is kept, and the data robustness is improved.

Description

Technical Field

[0001] This invention relates to the field of temperature-salinity profile observation technology, and specifically to a rapid observation data acquisition and processing system for temperature-salinity profiles. Background Technology

[0002] In marine environmental monitoring, temperature and salinity profile data are fundamental for understanding seawater density structure, ocean current evolution, and material transport. For long-term, unattended marine observation missions such as those using buoys or moored platforms, the observation unit typically consists of a microcontroller, a temperature and salinity (CTD) sensor, a communication link, and a satellite positioning / backhaul module. This requires periodically acquiring multi-channel data and remotely transmitting it back within a limited energy budget, while ensuring data alignment and traceability in both time and space. Affected by fluctuations in sea state, power supply, and satellite visibility, the system design must not only focus on the accuracy of individual measurements but also consider cross-period stability, availability during link congestion, and the ability to quickly trace anomalies and abnormal time periods during on-site maintenance.

[0003] Current practices often employ intermittent triggering or quasi-continuous power-on acquisition, without a strict distinction between the warm-up and acquisition phases. This can easily introduce drift during the cold start phase, and unnecessarily long power-on periods lead to high energy consumption, affecting observation duration. Multi-channel acquisition often relies on polling, but missing data is often handled by simply dropping bits or replacing them with interpolation / previous values. This is detrimental to array alignment and masks the location of missing data. Furthermore, the data is often stored in a single sampling, making it difficult to suppress transient spikes. Satellite backhaul is tightly coupled with the acquisition process, and retries under weak signal conditions can consume acquisition time, reducing the first-attempt success rate and slowing down the acquisition process. The system suffers from instability and lacks a mechanism to adjust transmission strategies based on visible satellite signals and signal strength, as well as sufficient buffering and rhythmic backtracking methods, making data prone to accumulation or loss. Regarding power supply safety, the isolation and current-limiting protection between sensor branches and the main control unit are insufficient; a short circuit or water ingress in a branch could trigger a cascading anomaly in the entire system. Furthermore, metadata such as measured values, communication status, and positioning information are not synchronously stored in the database at the same time reference, making it difficult to accurately review "which channel, when, and under what link conditions" produced a certain result, thus hindering anomaly localization and data filtering.

[0004] Therefore, it is necessary to propose an agile observation system for temperature-salinity profiles: In terms of time organization, preheating, acquisition, and dormancy are implemented in a time-division manner, using time-domain management to achieve measurement stability and controllable energy consumption; in terms of data acquisition and quality management, polling sampling combined with zeroing and position preservation for unanswered data, and averaging the results of multiple rounds of sampling within the same period, explicitly retains missing measurement locations while suppressing random noise; in terms of transmission scheduling, satellite backhaul and acquisition are decoupled, and single transmission or limited redundancy is adaptively selected based on the number of visible satellites and signal strength thresholds, ensuring that transmission failures do not occupy acquisition time slots, and using a FIFO buffer with a capacity limit and fixed-beat backordering to overcome link troughs; in terms of engineering reliability, short-circuit / leakage detection and electrical isolation are configured on the sensor branch side to prevent local failures from dragging down the main control; in terms of data management, measured values, channel addresses, timestamps, CRC, satellite status, and positioning information are synchronously written under the same time reference, forming a traceable full-link record, thereby achieving robust improvements in the corresponding weak links. Summary of the Invention

[0005] This invention provides a system for agile observation data acquisition and processing of temperature-salinity profiles.

[0006] The present invention solves the above-mentioned technical problems through the following technical solution: A rapid observation data acquisition and processing system for temperature-salinity profiles includes a main control and timing module, a sensor communication and acquisition module, a data processing and storage module, a satellite positioning module, a satellite data transmission module, and a power supply and protection module. Among them, the main control and timing modules are configured to sequentially execute sensor preheating, data acquisition and shutdown sleep according to preset time slots to form a time-slotted low-power working sequence; The sensor communication and acquisition module is configured to poll and sample multiple channels, and when any channel does not respond, the position of that channel is set to zero and maintained. The data processing and storage module is configured to perform statistical averaging on the sampling results of multiple rounds within the same collection period, and write them synchronously with the collection / link status to form a full-link traceability record; The satellite data transmission module is decoupled from the working sequence and performs adaptive transmission based on the number of visible satellites and signal strength thresholds. If the transmission fails, it will not occupy the time slot period of the working sequence, and the data to be transmitted will be put into the buffer until the back-ordering is completed. The power supply and protection module is configured to perform short circuit / leakage detection and electrical isolation on the sensor branches to prevent branch failures from affecting the main controller's operation according to the stated working sequence.

[0007] In a specific embodiment, the preset time slot includes: a first time slot for power-on preheating, a second time slot for starting data acquisition, and a third time slot for ending data acquisition and going into sleep mode.

[0008] In a specific embodiment, the first, second and third time slots are set to 0s, 120s and 600s, respectively.

[0009] In a specific embodiment, the multi-round sampling is ten rounds of sampling, and the fixed interval between adjacent polls is 3 seconds; the data processing and storage module calculates the arithmetic mean of the ten rounds of data from the same channel and then stores it.

[0010] In one specific embodiment, the sensor communication and acquisition module polls the Modbus master-slave protocol based on the RS-485 bus, and the determination of no response is based on timeout and / or CRC check failure.

[0011] In a specific embodiment, the synchronously written traceability record includes at least one of the following: channel address, request and response timestamps, response time, CRC check result, unanswered channel index, number of visible satellites, signal strength, transmission result and error code.

[0012] In a specific embodiment, the adaptive transmission strategy of the satellite data transmission module includes: performing a single transmission when the number of visible satellites is not less than 3 and the signal strength is greater than 45; performing 5 redundant transmissions when the number of visible satellites is not less than 2 and the signal strength is greater than 40; and queuing and periodically retrying when the number of visible satellites is below the threshold.

[0013] In one specific embodiment, the cache is a first-in-first-out (FIFO) queue with a capacity to store at least 15 days of data to be sent; when the link conditions meet the backordering strategy, the cached data is sent at a 2-minute interval.

[0014] In one specific embodiment, the power supply and protection module includes an electronic switch and a current limiting circuit for the sensor branch, which cuts off the corresponding branch and keeps the main control and other branches running normally when a short circuit or leakage event is detected.

[0015] In a specific embodiment, the satellite positioning module parses the NMEA-0183 message to obtain time, date and latitude and longitude information, and stores this information synchronously with the average data of each acquisition cycle and the traceability record under the same timestamp; the sensor is a conductivity-temperature-depth (CTD) sensor, suitable for temperature and salinity profiling tasks of buoys or moored platforms.

[0016] This invention provides a rapid observation data acquisition and processing system for temperature-salinity profiles, which has the following advantages compared to existing technologies: This system employs a time-slotted working sequence of "preheating-acquisition-sleep" to physically separate the sensor's thermal stability period from its effective acquisition period after power-on. In the first time slot, power is applied for preheating, allowing the sensing element and the front-end analog-to-digital link to reach a steady state, reducing the impact of cold-start drift on measurements. Acquisition begins in the second time slot, and the system promptly shuts down and enters sleep mode in the third time slot, minimizing unnecessary power-on time. This reduces average power consumption and extends battery life without sacrificing measurement stability. Compared to continuous power supply or no preheating distinction, this time-sequenced "stabilize first, then measure, then rest" approach trades time-domain management for energy efficiency and data consistency. The technical benefits are reflected in longer observation duration and more comparable profile data obtained with the same amount of power.

[0017] In terms of multi-channel data acquisition and quality management, the system employs RS-485 / Modbus polling combined with an array maintenance strategy of "zeroing and preserving the position when no response is received." Within the same acquisition cycle, each channel undergoes ten rounds of sampling at fixed intervals, with the arithmetic mean ultimately being entered into the database. RS-485's differential transmission and CRC check help maintain link robustness under long-term and weak interference conditions. The zeroing and position preservation strategy does not mask missing measurements with interpolation or previous value backfilling, but rather explicitly identifies disconnections while maintaining the channel order, facilitating subsequent location of anomalies at specific channels and times. The ten-round average suppresses random noise and transient spikes within the time window, preventing single outliers from being the primary data imported into the database. The principle behind this combination is to collaboratively achieve link reliability, missing measurement visibility, and statistical robustness within the same acquisition framework, thereby realistically improving the completeness and interpretability of the dataset without exaggerating the filtering effect.

[0018] For data backhaul under weak signal conditions in the field, the system decouples satellite data transmission from the acquisition sequence, achieving "no time slot occupation in transmission failure" through independent timing and task scheduling. Single or limited redundancy transmission is selected based on the threshold of the number of visible satellites and signal strength. When conditions are insufficient, data is buffered in a FIFO buffer and then backloaded at a fixed interval once the link improves. The technical mechanism uses link status awareness to drive the transmission strategy, allowing retry behavior to give way to the main acquisition process in terms of time, avoiding the amplification of the coupling between "backhaul blocking and acquisition delay." Simultaneously, limited redundancy improves the initial success rate within marginal energy consumption, and the buffer overcomes temporary link troughs. The resulting effect is: without increasing the duty cycle on the acquisition side, the actual effective backhaul rate and latency distribution are smoother. The buffer capacity and backload interval (e.g., approximately 15 days of storage, 2 minutes of backload) provide a predictable upper limit for on-site maintenance, but it does not guarantee zero data loss under extreme and continuous obstruction conditions. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 The diagram shown is a system framework diagram of Embodiment 1; Figure 2 The following is the timed loop program framework of Example 1; Figure 3 The diagram shown is a flowchart of the Modbus polling data acquisition program in Example 1. Figure 4 The diagram shows the CTD working time points and program logic of Example 1. Figure 5 The diagram shows the CTD data processing logic of Example 1; Figure 6 The following is the logic of the BeiDou data transmission program in Example 1; Figure 7 The diagram shown is a flowchart of the satellite positioning module in Embodiment 1. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1: A rapid observation data acquisition and processing system for temperature-salinity profiles This embodiment uses a moored buoy at sea as a carrier and a low-power microcontroller as the main control core. It integrates a CTD multi-channel sensor, an RS-485 / Modbus communication link, a dual-mode GNSS (including BeiDou) positioning and BeiDou short message transmission module, and a power supply protection unit with branch current limiting and electronic switches to construct a time-sharing observation unit operating in a "preheat-acquisition-sleep" mode. Under a limited power budget, the system periodically completes profile acquisition, data quality management, and remote transmission, and synchronizes with link and positioning metadata during data storage to achieve full-process traceability.

[0023] The main control unit uses an ultra-low power MCU (such as the STM32L series) and an external independent RTC crystal oscillator to provide a highly stable time base. The sensor side is equipped with a set of CTD channels, all connected to an RS-485 differential bus. The MCU is connected to this bus via an isolated transceiver. Hardware-wise, electronic switches and current-limiting resistors are connected in series before each sensor branch, and current detection is configured to determine short-circuit / leakage events. The BeiDou / GNSS positioning module provides NMEA-0183 messages via UART, and the BeiDou short message (or equivalent satellite data transmission) module is connected via an independent UART; the two do not occupy the RS-485 bus. The storage section uses a non-volatile memory (such as SPINOR Flash or an SD card) to store periodic data, masks, and logs. The entire unit is powered by a lithium battery pack and a DC-DC voltage regulator module. The main controller can independently control the power-on and power-off of the CTD branches via a power management chip.

[0024] The firmware employs a two-layer scheduling mechanism: an "acquisition sequence task" with the RTC as the clock source, and a decoupled "data transmission task." The acquisition sequence runs in three time slots: 0s, 120s, and 600s. At 0s, the main controller closes the electronic switch of the CTD branch, powering on and preheating the sensor and the front-end analog-to-digital link. At 120s, the acquisition phase begins, with the main controller polling multiple channels at fixed intervals of 3s, executing 10 rounds consecutively. At 600s, acquisition ends, the average value of each channel over ten rounds is calculated and written to storage, and then the CTD branch power is disconnected, entering sleep mode. The data transmission task resides in the background, with its independent timer checking the visible satellite and signal strength status at fixed intervals. If the threshold is met, the latest untransmitted batch is retrieved and a data transmission is triggered; otherwise, the batch is written to a FIFO for later readjustment. Branch protection is linked at the interrupt level: if an overcurrent or leakage threshold is detected, the corresponding electronic switch is immediately shut down and the event is recorded, while the main controller and other branches continue to operate according to the predetermined time slots.

[0025] Within each acquisition cycle, the master controller, acting as the Modbus master, sequentially sends register read commands to preset slave addresses, requesting register values ​​such as temperature, conductivity, and pressure (depth), and sets timeouts and CRC checks for each request. For channels that return within the timeout and have a correct CRC, the measured value for that round is recorded; for channels that do not respond within the timeout or have a wrong CRC, no interpolation or previous value backfilling is performed, but instead, a zero value is written to the channel's position, and the channel is marked as unresponsive in the "mask". After 10 rounds, the master controller calculates the arithmetic mean of the 10 samples for each channel within that cycle, and stores it as the representative value for that cycle; the mean calculation is not performed across cycles to avoid profile broadening caused by cross-period statistics. This "zeroing and position preservation" strategy explicitly preserves the missing measurement positions and order, facilitating the subsequent location of anomalies in specific channels and cycles, while the ten-round mean suppresses random noise and transient spikes, making the data for the same cycle more statistically robust.

[0026] During the acquisition phase, GNSS serial port monitoring is initiated in parallel to parse RMC, GGA, and other statements in NMEA-0183, extracting UTC time, date, and latitude / longitude. If multiple frames of positioning information exist within the current period, the frame closest in time to the end of sampling is used for indexing. When writing periodic data, the master controller packages and stores log fields such as "channel average array," "unanswered mask," "GNSS time and latitude / longitude," "number of visible satellites and signal strength," and "timestamp of each polling request / response, response time, and CRC result" with the same timestamp, ensuring time alignment between measured values ​​and link events. This simultaneous writing method of "measured values ​​+ metadata" does not change the accuracy of the sensor itself but significantly improves data traceability.

[0027] The data transmission task operates according to a state machine. First, it periodically reads the number of visible satellites and signal strength. Second, when the number of visible satellites is ≥3 and the signal strength is >45, a single transmission is performed directly on the latest untransmitted batch; when the number of visible satellites is ≥2 and the signal strength is >40, to offset the uncertainty of the edge link, 5 limited-redundancy transmissions are performed on this batch; when the above conditions are not met, no wasteful retries are performed, but the batch is written to the FIFO buffer. Third, when the link improves, the FIFO is checked every 2 minutes at a fixed interval until it is empty or the link deteriorates again. The buffer capacity is configured for a batch size of no less than 15 days, and a gentle backoff strategy of "first-in, first-out" is adopted when storage space is insufficient, while recording the discard event. The entire backhaul process is driven by an independent timer, without preempting the time slots of the acquisition sequence, so that "transmission failure" does not negatively affect the sampling cycle.

[0028] After power-on, the ADC samples the current of each CTD branch. If a persistent abnormality or obvious leakage current characteristic exceeding the current limiting threshold is detected, the main controller immediately disconnects the electronic switch of that branch and generates a protection event containing the channel address, trigger threshold, and occurrence time, which is then written to the log. This strategy limits the fault to a single branch, preventing power drops or noise crosstalk from spreading to the main controller and other channels, thus ensuring that the remaining channels can still complete data acquisition and subsequent data transmission within the current cycle.

[0029] Under typical settings, the three time slots are 0s warm-up, 120s sampling start, and 600s end with sleep mode; the polling interval is 3s, and the total sampling time for ten rounds is approximately 27-30 minutes (including protocol round-trip overhead); GNSS parsing and log writing converge around 600s, followed by power-off sleep until the RTC wakes up in the next cycle. Using a 24-hour cycle, the above "0 / 120 / 600s" can be aligned to a fixed hourly window according to the task, facilitating subsequent data stitching. All hardware components are readily available; the firmware protocol is based on the standard Modbus RTU and NMEA-0183; the data transmission interface follows the BeiDou short message API specification; and the FIFO and log storage format uses a fixed-length header + variable-length payload to balance parsing efficiency and space utilization. This embodiment does not make any promises of absolutely no data loss under extreme continuous occlusion conditions. However, in common weak signal and intermittent occlusion environments, through adaptive thresholds, limited redundancy, and rhythmic backordering, the stability of the backhaul can be maintained without increasing the acquisition duty cycle. Through the combination of "zeroing and position preservation + ten rounds of averaging + synchronous logs", the integrity and interpretability of the dataset can be improved without introducing complex algorithms, and it is also convenient for on-site maintenance and post-event traceability.

[0030] After being woken up by the RTC at a predetermined time, the system first initiates a stable warm-up for the CTD branch, then enters a fixed-cycle polling sampling phase and completes ten rounds of statistical analysis, continuously parsing GNSS information and recording link events. After sampling, all data is stored in the database and the system is powered off and put into hibernation. Simultaneously, the background data transmission adaptively triggers transmission or enqueueing based on satellite status. If any branch experiences an anomaly, a protection mechanism isolates it without affecting the overall cycle. Thus, the hardware and software work together to form a closed loop across the time domain, link layer, and storage layer, enabling the system to achieve a feasible balance of energy consumption, stability, and traceability in long-term, unattended maritime scenarios through engineering means.

[0031] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0032] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these 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.

Claims

1. A rapid observation data acquisition and processing system for temperature-salinity profiles, characterized in that, It includes a main control and timing module, a sensor communication and acquisition module, a data processing and storage module, a satellite positioning module, a satellite data transmission module, and a power supply and protection module; Among them, the main control and timing modules are configured to sequentially execute sensor preheating, data acquisition and shutdown sleep according to preset time slots to form a time-slotted low-power working sequence; The sensor communication and acquisition module is configured to poll and sample multiple channels, and when any channel does not respond, the position of that channel is set to zero and maintained. The data processing and storage module is configured to perform statistical averaging on the sampling results of multiple rounds within the same collection period, and write them synchronously with the collection / link status to form a full-link traceability record; The satellite data transmission module is decoupled from the working sequence and performs adaptive transmission based on the number of visible satellites and signal strength thresholds. If the transmission fails, it will not occupy the time slot period of the working sequence, and the data to be transmitted will be put into the buffer until the back-ordering is completed. The power supply and protection module is configured to perform short circuit / leakage detection and electrical isolation on the sensor branches to prevent branch failures from affecting the main controller's operation according to the stated working sequence.

2. The system according to claim 1, characterized in that, The preset time slots include: a first time slot for power-on preheating, a second time slot for starting data acquisition, and a third time slot for ending data acquisition and going into sleep mode.

3. The system according to claim 2, characterized in that, The first, second, and third time slots are set to 0s, 120s, and 600s, respectively.

4. The system according to claim 1, characterized in that, The multi-round sampling consists of ten rounds, with a fixed interval of 3 seconds between adjacent rounds; the data processing and storage module calculates the arithmetic mean of the ten rounds of data from the same channel and then stores it.

5. The system according to claim 1, characterized in that, The sensor communication and acquisition module polls the sensor based on the RS-485 bus and Modbus master-slave protocol. The failure to respond is determined based on timeout and / or CRC check failure.

6. The system according to claim 1, characterized in that, The synchronously written traceability record includes at least one of the following: channel address, request and response timestamps, response time, CRC check result, unanswered channel index, number of visible satellites, signal strength, transmission result and error code.

7. The system according to claim 1, characterized in that, The adaptive transmission strategy of the satellite data transmission module includes: performing a single transmission when the number of visible satellites is not less than 3 and the signal strength is greater than 45; performing 5 redundant transmissions when the number of visible satellites is not less than 2 and the signal strength is greater than 40; and queuing and periodically retrying when the number of visible satellites is below the threshold.

8. The system according to claim 1, characterized in that, The cache is a first-in-first-out (FIFO) queue with a capacity to store at least 15 days of data to be sent; when the link conditions meet the backordering strategy, the cached data is sent at a 2-minute interval.

9. The system according to claim 1, characterized in that, The power supply and protection module includes electronic switches and current limiting circuits for the sensor branches. When a short circuit or leakage event is detected, the corresponding branch is disconnected while the main control and other branches remain in normal operation.

10. The system according to claim 1, characterized in that, The satellite positioning module parses the NMEA-0183 message to obtain time, date, and latitude and longitude information, and stores this information synchronously with the average data of each acquisition cycle and the traceability record under the same timestamp; the sensor is a conductivity-temperature-depth (CTD) sensor, suitable for temperature and salinity profiling tasks of buoys or moored platforms.

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