A concrete mixer truck feeding flow automatic compensation control system and method

Abstract

This invention relates to the field of concrete machinery equipment control technology, and discloses an automatic compensation control system and method for the feed flow of a concrete mixer truck. The system includes a data acquisition module, a state calibration module, a signal decoupling module, a parameter calculation module, and a compensation execution module. The system synchronously acquires the weight signal at the fixed end, the transient pressure signal at the moving end, and the absolute phase angle signal; it separates and extracts the low-frequency baseband pressure signal and converts it to obtain a real-time angular domain pulse signal; based on this, it calculates the chute retention index, volume tolerance parameter, and material transfer leakage prevention coefficient; finally, based on the chute retention index superimposed with the compensation speed increment, it uses the volume tolerance parameter for amplitude limiting constraint, and cuts off the feeding action when the leakage prevention coefficient exceeds the limit. By integrating multi-source physical parameters and dynamically and adaptively adjusting the feed speed of the mixing drum, the system effectively solves the problems of material retention and accumulation at the chute and late-stage overflow, and automatically interlocks protection in case of leakage, improving feeding efficiency and safety.

Description

Technical Field

[0001] This invention relates to the field of concrete machinery and equipment control technology, specifically to an automatic compensation control system and method for the feed flow of a concrete mixer truck. Background Technology

[0002] Concrete mixer trucks play a crucial role in the transportation of construction materials. During routine feeding operations, the stationary batching plant opens its discharge gate, allowing concrete materials to be discharged through a transition chute into the mixer truck parked below, according to the set mix proportions. During this process, the mixer drum, controlled by the onboard drive system, typically maintains a preset constant rotation speed. The axial thrust generated by the spiral blades on the inner wall of the drum guides the material falling into the drum opening towards the bottom of the drum until the target loading capacity is reached, at which point the gate closes, stopping the feeding operation.

[0003] In existing feeding control modes, the mixing drum maintains a constant rotation speed, making it difficult to adapt to changes in material flow and loading space. When loading high-viscosity concrete, the material flow is obstructed at the transition chute, easily leading to stagnation and accumulation. Relying on a constant feeding speed is insufficient to generate enough suction force to quickly engulf the accumulated material into the drum, affecting overall feeding efficiency. Furthermore, in the later stages of feeding, the remaining receiving space inside the mixing drum gradually decreases. If the system continues to maintain the initial feeding speed, the force generated by the continuous agitation of the material by the helical blades can easily cause material to overflow backwards at the inlet area. Existing technology struggles to balance efficient initial throughput with safe loading in the later stages.

[0004] Existing feeding operations lack a collaborative data exchange mechanism between the stationary mixing plant and the mobile mixer truck. The mixing plant's material discharge control primarily relies on the station's weighing system to execute according to predetermined targets, while the mixer truck passively receives the material. Due to the lack of verification methods for cross-equipment material quality transfer status, when issues arise such as vehicle parking position deviation, inaccurate chute alignment, or damage to related guide components, the material released from the station may deviate from its set trajectory and fail to fall into the mixing drum. Faced with such material loss anomalies, the existing system cannot promptly identify material differences between the front and rear ends and trigger cut-off protection, causing the discharge process to continue, resulting in material waste and environmental pollution. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an automatic compensation control system and method for the feed flow of concrete mixer trucks. This solves the problem that existing concrete mixer trucks lack data interaction and status coordination between the fixed-end mixing station and the mobile-end mixing truck during the feeding process. This results in the system being unable to perceive the flow status of materials at the transition chute and the receiving capacity of the mixing drum, which can easily lead to material stagnation and overflow or reverse splashing at the end of the feeding process.

[0006] To achieve the above objectives, the present invention provides an automatic compensation control system for the feed flow of a concrete mixer truck, comprising hardware facilities distributed at a fixed concrete mixing plant and a mobile concrete mixer truck. The concrete mixing plant is equipped with a discharge gate and a weighing sensor, and the concrete mixer truck is equipped with a dynamic pressure transmitter and an absolute encoder. The automatic compensation control system for the feed flow of the concrete mixer truck includes: a data acquisition module, a status calibration module, a signal decoupling module, a parameter calculation module, and a compensation execution module.

[0007] The data acquisition module is used to synchronously acquire the weight signal output by the weighing sensor, the transient pressure signal output by the dynamic pressure transmitter, and the absolute phase angle signal output by the absolute encoder based on the precise time protocol. It adds timestamps to the acquired data to perform rigid time axis alignment, thereby eliminating the time difference caused by cross-device communication delays and unifying different physical parameters under the same time reference.

[0008] The state calibration module is used to extract the average value of the low-frequency baseband pressure signal as the no-load static pressure constant during the no-load rotation stage, and to extract the absolute phase corresponding to the peak value of the angular domain pulsation signal as the reference material drop phase during the initial feeding stage. By extracting the state characteristics of the corresponding stages, the measurement reference drift caused by the impedance difference of the hydraulic system of different displacement mixer trucks and the difference in physical properties of different batches of materials is eliminated.

[0009] The signal decoupling module performs filtering and separation processing on transient pressure signals, independently extracting the low-frequency baseband pressure signal and the high-frequency AC pressure component. It then combines the absolute phase angle signal to convert the high-frequency AC pressure component into an angular domain signal and calculates and outputs a real-time angular domain pulse signal. This separates the pressure signal, which is a mixture of overall material load and drop impact, and uses spatial phase to replace the time independent variable for equal-angle resampling, eliminating the interference of rotational speed fluctuations on the extraction of material impact features.

[0010] The parameter calculation module is used to calculate the chute retention index based on the real-time angular domain pulse signal, the reference material drop phase, and the weight signal; to calculate the volume tolerance parameter based on the low-frequency baseband pressure signal and the no-load static pressure constant; and to calculate the material transfer leakage prevention coefficient based on the weight signal and the low-frequency baseband pressure signal. Specifically, the chute retention index, combined with the discharge flow rate, is used to quantify the degree of material flow obstruction; the volume tolerance parameter uses the ratio of the pressure increment to the safety limit to reflect the remaining receiving space of the mixing drum; and the material transfer leakage prevention coefficient uses the mapping residual between the mass integral of the released material and the load pressure increment to characterize the material transfer state.

[0011] The compensation execution module uses a preset base feed speed as a benchmark, superimposed with a compensation speed increment positively correlated with the chute retention index, and simultaneously uses a volume tolerance parameter to limit the target speed, generating a comprehensive target speed command to adjust the feed speed of the mixing drum. Furthermore, when the material transfer leakage prevention coefficient exceeds the preset mass conservation boundary condition, it synchronously drives the discharge gate to close and stops the mixing drum rotation. By combining the base feed speed with the compensation speed increment, the mixing drum's entrainment capacity for material is enhanced. In the later stages of feeding, the volume tolerance parameter is used to limit the flow to prevent material overflow, and a cut-off command is executed when material leakage occurs.

[0012] A second aspect of the present invention provides an automatic compensation control method for the feed flow rate of a concrete mixer truck, the method comprising the following steps: Based on a precise time protocol, the weight signal output by the weighing sensor, the transient pressure signal output by the dynamic pressure transmitter, and the absolute phase angle signal output by the absolute encoder are synchronously acquired, and a timestamp is added to the acquired data for rigid alignment of the time axis. In the no-load rotation stage, the average value of the low-frequency baseband pressure signal is extracted as the no-load static pressure constant, and in the initial feeding stage, the absolute phase corresponding to the peak value of the angular domain pulsation signal is extracted as the reference dropping phase. The transient pressure signal is filtered and separated to independently extract the low-frequency baseband pressure signal and the high-frequency AC pressure component. The high-frequency AC pressure component is converted into an angular domain signal by combining the absolute phase angle signal and the real-time angular domain pulse signal is calculated and output. The chute retention index is calculated based on the real-time angle domain pulse signal, the reference material dropping phase, and the weight signal. The volume tolerance parameter is calculated based on the low-frequency baseband pressure signal and the no-load static pressure constant. The material transfer leakage prevention coefficient is calculated based on the weight signal and the low-frequency baseband pressure signal. Based on the system's preset basic feed speed, a compensation speed increment that is positively correlated with the chute retention index is superimposed. At the same time, the target speed is constrained by the volume tolerance parameter, and a comprehensive target speed command is generated to adjust the feed speed of the mixing drum. Furthermore, when the material transfer leakage prevention coefficient exceeds the preset mass conservation boundary condition, the discharge gate is simultaneously driven to close and the rotation of the mixing drum is stopped.

[0013] This invention provides an automatic compensation control system and method for the feed flow rate of a concrete mixer truck. It has the following beneficial effects: 1. This invention calculates the chute retention index by extracting the angular domain pulse signal, the reference material drop phase, and the weight signal, and then superimposes a positively correlated compensating speed increment onto the base feed speed. This technical feature can quantitatively assess the degree of flow obstruction of materials at the transition chute in real time. When material accumulates, the stirring drum speed is actively increased, thereby enhancing the entrainment capacity of the internal spiral blades for materials, solving the retention problem of high-viscosity materials at the chute and improving feeding efficiency.

[0014] 2. This invention calculates a volume tolerance parameter by extracting the average value of the low-frequency baseband pressure signal and the no-load static pressure constant, and then uses this volume tolerance parameter to limit the comprehensive target speed command. This technical feature can dynamically reflect the remaining receiving space inside the mixing drum, and automatically reduce the upper limit of the target speed as the material increases in the later stage of feeding, avoiding material overflow caused by improper speed control or volume approaching the limit, thus ensuring the safety of the feeding process.

[0015] 3. This invention calculates a material transfer leakage prevention coefficient by combining the weight signal output from the fixed-end weighing sensor with the low-frequency baseband pressure signal from the mobile end. When this coefficient exceeds a preset boundary condition, it synchronously drives the gate to close and the mixing drum to stop. This technical feature establishes a cross-equipment material quality verification mechanism, which can quickly identify sudden changes in the quality mapping residual and automatically cut off the feeding action when material fails to fall into the mixing drum due to chute alignment deviation, thereby preventing material loss and on-site environmental pollution. Attached Figure Description

[0016] Figure 1 This is a system framework diagram of the present invention; Figure 2 This is a flowchart of the method of the present invention; Figure 3 This is a timing diagram of multi-source heterogeneous data acquisition and time axis alignment according to the present invention; Figure 4 This is the timing diagram of the state calibration logic of the present invention; Figure 5 This is a schematic diagram of the signal decoupling and angular domain conversion algorithm of the present invention; Figure 6 This is a schematic diagram illustrating the parametric calculation and multidimensional feature mapping principle of the present invention. Figure 7 This is the compensation execution control logic diagram of the present invention; Figure 8 The experimental group and the control group of this invention are shown as dynamic adjustment response curves of the feed speed throughout the entire cycle. Figure 9 This is a dynamic evolution trend diagram of the chute retention index and volume tolerance parameter in the experimental group of this invention.

[0017] Among them, 10 is the data acquisition module; 20 is the status calibration module; 30 is the signal decoupling module; 40 is the parameter calculation module; and 50 is the compensation execution module. Detailed Implementation

[0018] The technical solutions in 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.

[0019] See attached document Figure 1 , Figure 1 This is a schematic diagram of an automatic compensation control system for the feed flow rate of a concrete mixer truck according to an embodiment of the present invention. The present invention provides an automatic compensation control system for the feed flow rate of a concrete mixer truck, which may include: a data acquisition module 10, a status calibration module 20, a signal decoupling module 30, a parameter calculation module 40, and a compensation execution module 50.

[0020] The system's hardware is distributed across a fixed concrete batching plant and mobile concrete mixer trucks. The concrete batching plant is equipped with a discharge gate, gate actuator, weighing sensors, and a main control unit. The concrete mixer trucks have a dynamic pressure transmitter installed at the pressure measurement interface of their closed-loop hydraulic transmission system, an absolute encoder installed at the mixing drum rotation mechanism, and an onboard edge gateway mounted on the vehicle body. The main control unit at the plant and the onboard edge gateway establish a communication link via an industrial wireless communication network.

[0021] The data acquisition module 10 synchronizes the clocks of the station-side main control unit and the vehicle-mounted edge gateway based on a precise time protocol. Throughout the entire feeding cycle, the data acquisition module 10 synchronously acquires the weight signal output by the weighing sensor, the transient pressure signal output by the dynamic pressure transmitter, and the absolute phase angle signal output by the absolute encoder according to a set discrete time step. The data acquisition module 10 timestamps the heterogeneous data and stores it in a time buffer, completing the rigid alignment of multi-source physical parameters on the time axis.

[0022] The state calibration module 20 extracts baseline parameters using the specific physical state at the initial stage of feeding. During the no-load rotation stage when the feeding program starts and the discharge gate is closed, the state calibration module 20 extracts the average value of the hydraulic low-frequency baseband signal and latches it as the no-load static pressure constant. In the initial stage when the discharge gate is open and the cumulative feeding amount has not exceeded the set feeding quality threshold, the state calibration module 20 extracts the absolute phase corresponding to the peak value of the angular domain pulsation signal and latches it as the reference dropping phase.

[0023] The signal decoupling module 30 receives time-aligned data output from the data acquisition module 10 and performs dual-branch filtering and separation processing on the transient pressure signal. The first branch extracts the low-frequency baseband pressure signal through a low-pass filter, and the second branch extracts the high-frequency pressure AC component through a band-pass filter. The signal decoupling module 30 combines the absolute phase angle signal to convert the high-frequency pressure AC component into an angular domain signal with equal angular intervals, and performs a synchronous time averaging algorithm to calculate and output a real-time angular domain pulse signal.

[0024] The parameter calculation module 40 calculates physical characteristic quantities based on the signal output by the signal decoupling module 30. The parameter calculation module 40 extracts the transient peak phase of the real-time angular domain pulse signal, calculates its spatial offset from the reference material discharge phase, and calculates the chute retention index by combining the single-cycle angular domain energy integral and the real-time discharge flow rate obtained based on the weight signal differential. The parameter calculation module 40 extracts the mean and fluctuation range of the low-frequency baseband pressure signal within the real-time sliding time window, and performs dimensionless processing by combining it with the no-load static pressure constant to calculate the volume tolerance parameter. The parameter calculation module 40 calculates the dynamic ratio of the time integral of the real-time discharge flow rate to the mean of the low-frequency baseband pressure signal, extracts the nonlinear mapping residual between the station-end release mass and the vehicle-end load increment, and generates a material handover leakage prevention coefficient.

[0025] The compensation execution module 50 receives multi-dimensional feature parameters output by the parameter calculation module 40. Addressing the material accumulation problem at the feed transition chute and the limitation of the mixing drum's remaining capacity, the compensation execution module 50 uses the system's preset base feed speed as a benchmark, superimposing a compensation speed increment positively correlated with the real-time chute retention index. Simultaneously, it utilizes the volume tolerance parameter as a safety extreme boundary for dynamic limiting constraints, generating the final comprehensive target speed command. This command is then output to the electro-hydraulic proportional valve of the hydraulic system, driving the underlying mechanical mechanism to perform adaptive adjustment of the mixing drum's speed. Before outputting the comprehensive target speed command, the compensation execution module 50 monitors the material transfer leakage prevention coefficient. When the material transfer leakage prevention coefficient exceeds the preset mass conservation boundary condition, the compensation execution module 50 determines that the chute has missed its target and forcibly generates a highest-priority emergency cut-off command. This command, via the vehicle communication bus, oversteps its authority to drive the station-end discharge gate to close urgently, simultaneously cutting off the rotational power of the mixing drum at the vehicle end.

[0026] See attached document Figure 2 , Figure 2 This is a flowchart of a method according to an embodiment of the present invention. The present invention provides an automatic compensation control method for the feed flow rate of a concrete mixer truck, comprising the following steps: S10 synchronously acquires the weight signal of the weighing sensor, the transient pressure signal of the dynamic pressure transmitter, and the absolute phase angle signal of the absolute encoder based on the precise time protocol, and timestamps the acquired data to achieve rigid alignment of the time axis. S20: During the no-load rotation phase, the average value of the hydraulic low-frequency baseband signal is extracted as the no-load static pressure constant; during the initial feeding phase, the absolute phase corresponding to the peak value of the angular domain pulsation signal is extracted as the reference dropping phase. S30 performs dual-branch filtering and separation processing on the transient pressure signal, extracts the low-frequency baseband pressure signal and the high-frequency pressure AC component, combines the absolute phase angle signal to convert the high-frequency pressure AC component into an angular domain signal and executes a synchronous time averaging algorithm to generate a real-time angular domain pulse signal. S40 calculates the chute retention index based on the spatial offset between the transient peak phase of the real-time angular domain pulse signal and the reference material dropping phase, the angular domain energy integral, and the real-time material discharge flow rate; calculates the volume tolerance parameter based on the mean, fluctuation range, and no-load static pressure constant of the low-frequency baseband pressure signal; and calculates the dynamic ratio of the time integral of the real-time material discharge flow rate to the mean of the low-frequency baseband pressure signal to generate the material handover leakage prevention coefficient. S50 uses the system's preset basic feed speed as a benchmark, superimposes a compensation speed increment that is positively correlated with the real-time chute retention index, and combines the volume tolerance parameter to dynamically limit the target speed to generate a comprehensive target speed command to adjust the feed speed of the mixing drum. In the whole process monitoring, when the material transfer leakage prevention coefficient exceeds the preset mass conservation boundary condition, the highest priority emergency cut-off command is generated, which synchronously drives the discharge gate to close and stops the rotation of the mixing drum.

[0027] See attached document Figure 3 , Figure 3 This is a timing diagram of multi-source heterogeneous data acquisition and time axis alignment according to an embodiment of the present invention. In this embodiment, the data acquisition module 10 is deployed between the station-side main control unit and the vehicle-mounted edge gateway to establish a globally unified time reference and acquire different physical quantities distributed at the fixed and mobile ends. Considering that concrete mixing plants and mixer trucks typically use industrial wireless communication networks for data interaction, and that the wireless link has uncontrollable network latency and data packet arrival time jitter, directly performing logical processing according to the order of data reception often easily leads to a certain degree of misalignment in the time series between the hydraulic pulse phase of the mobile end and the change in material feeding weight at the fixed end.

[0028] To eliminate the time difference caused by spatial distance and wireless transmission, the data acquisition module 10 establishes a clock synchronization mechanism before starting data acquisition. As a preferred approach, the station-side master control unit acts as the master clock node, and the vehicle-mounted edge gateway acts as the slave clock node. Both execute the IEEE 1588 precise time protocol via a local area network. For the underlying synchronization message exchange and local clock offset compensation process of the IEEE 1588 precise time protocol, those skilled in the art can refer to existing network time synchronization standard protocol literature for configuration and implementation. Its underlying network protocol operation mechanism is well-known in the field and will not be elaborated upon here. After protocol interaction, the local clocks of the vehicle and station ends are basically kept under a unified time base.

[0029] Throughout the entire feeding cycle, the data acquisition module 10 performs synchronous acquisition operations according to a set discrete time step. The value of this discrete time step is typically set between 1 and 10 milliseconds, and its specific value can be selected based on the highest rotation frequency of the mixing drum and the Nyquist sampling theorem to ensure that the high-frequency pulsation characteristic acquisition is not distorted. At the station, the weighing sensor outputs a weight signal containing the weight information of the material in the hopper. At the vehicle, the dynamic pressure transmitter outputs the transient pressure signal of the hydraulic transmission system, and the absolute encoder synchronously outputs the absolute phase angle signal of the mixing drum rotation. Upon acquiring their respective sensor electrical signals, the station-end main control unit and the vehicle-mounted edge gateway directly append the currently synchronized local time value to the data sequence via the underlying hardware, generating a data packet with a hardware timestamp. The vehicle-mounted edge gateway continuously transmits the timestamped transient pressure signal and absolute phase angle signal to the station-end main control unit via a wireless network.

[0030] The station-side main control unit allocates a storage space of preset capacity as a time buffer. The depth of this time buffer typically corresponds to a physical time span of 100 to 300 milliseconds, used to absorb common network communication jitter. After receiving data packets from the vehicle, the station-side main control unit temporarily stores them in the time buffer. The data acquisition module 10 parses the hardware timestamps of all data packets in the time buffer, extracts and binds weight signals, transient pressure signals, and absolute phase angle signals carrying the same timestamp into a data set of the same sampling time, and performs a rigid time axis alignment operation.

[0031] When a brief fluctuation in the wireless network causes some data packets at the vehicle end to not be strictly aligned according to discrete time steps, the data acquisition module 10 uses an interpolation algorithm to perform time axis alignment compensation calculations. From a physical perspective, although transient pressure exhibits high-frequency pulsations, within millisecond-level time segments, fluid pressure changes possess physical continuity. Therefore, linear interpolation can restore the true physical pressure transition state with extremely low computational overhead. Taking the alignment compensation of transient pressure signals as an example, the calculation process is as follows: ; In the formula, This represents the time corresponding to the standard discrete time step set by the system. This indicates that after interpolation alignment compensation, at time... The corresponding transient pressure signal value; and These represent the distances in the time buffer pool. The two most recent vehicle-side actual sampling timestamps, and satisfying ; and These represent the actual sampling timestamps. and The actual acquired value of the transient pressure signal at the corresponding moment.

[0032] To ensure the integrity of the algorithm logic and avoid interpolation distortion caused by severe network congestion, the data acquisition module 10 is internally configured with a maximum allowable interpolation interval threshold. Before performing alignment compensation calculations, the system verifies the actual sampling timestamp difference. - Whether the difference exceeds the maximum allowable interpolation interval threshold. When it is determined that the difference exceeds the safe range, the data acquisition module 10 actively abandons the compensation calculation at the current moment and triggers a communication quality degradation state to prevent the introduction of erroneous constructed data into subsequent control links. Through the above alignment and compensation mechanism, the data acquisition module 10 reconstructs heterogeneous data into a time-synchronized data sequence and outputs it to the subsequent processing flow.

[0033] See attached document Figure 4 , Figure 4 This is a timing diagram of the state calibration logic according to an embodiment of the present invention. In this embodiment, the state calibration module 20 is mainly used to solve the system reference drift problem caused by the impedance difference of the hydraulic transmission system of different displacement mixer trucks and the difference in physical properties of different batches of concrete. In order to establish a unified reference condition, the state calibration module 20 uses the objective state of a specific physical stage during the feeding process as a reference point to automatically extract baseline parameters, thereby providing a consistent measurement and control reference.

[0034] When the feeding program issues a start command and the discharge gate controlled by the station is closed, the system determines that it is currently in the no-load rotation stage. During this stage, there is no external material interference inside the mixing drum, and the system resistance mainly comes from the viscous friction of the hydraulic circuit itself and the mechanical internal resistance of the reducer. The state calibration module 20 extracts the hydraulic low-frequency baseband signal during this physical stage. To eliminate short-term random mechanical interference, the state calibration module 20 sets a preset length of sliding time window. As a preferred method, the time span of the sliding time window is set to cover the total time of 3 to 5 complete cycles of continuous constant speed rotation of the mixing drum. In order to convert this number of cycles into a specific physical time span, the state calibration module 20 uses the phase difference between adjacent sampling points of the absolute encoder to calculate the current real-time rotational angular velocity, and then calculates the specific number of seconds of the sliding time window to ensure that the data extraction is statistically significant.

[0035] The state calibration module 20 performs summation and averaging on the hydraulic low-frequency baseband signal within the sliding time window to calculate the no-load static pressure constant. The specific calculation formula is as follows: ; In the formula, This represents the calculated no-load static pressure constant; This indicates the total number of valid sampling points contained within the set sliding time window; Indicates the first time within the sliding time window The instantaneous values ​​of the hydraulic low-frequency baseband signal corresponding to each discrete time step. After the no-load static pressure constant is generated, it is latched into the internal register by the state calibration module 20 to characterize the basic hydraulic internal resistance of the current vehicle.

[0036] As the discharge gate is opened by the actuator, the system enters the initial feeding stage. In the transition zone when the gate is initially open, the surface of the concrete transition chute is typically free of prior material accumulation, and the material flows smoothly under gravity with relatively low resistance. The status calibration module 20 monitors the cumulative feed amount fed back by the weighing sensor in real time and compares it with the system's preset feed mass threshold. The feed mass threshold is typically set between 300 kg and 500 kg, corresponding to the initial few seconds after the feeding action begins.

[0037] Within the time interval during which the cumulative feed amount does not exceed the feed quality threshold, the state calibration module 20 acquires the real-time angular domain pulsation signal after conversion processing. Since the material flow trajectory is close to an ideal parabola at this time, the spatial intersection position of the impacting spiral blades inside the mixing drum is relatively fixed. The state calibration module 20 runs an extreme value peak-finding algorithm to locate the main peak of the angular domain pulsation signal within the interval. For extreme value peak-finding and envelope feature extraction of one-dimensional discrete digital signals, those skilled in the art can use conventional differential zero-crossing detection or window function peak search methods; the specific program implementation is a well-known technology in the field and will not be elaborated here.

[0038] To ensure the integrity of the algorithm logic and prevent false locking caused by underlying mechanical vibration, the state calibration module 20 is configured with a peak salience threshold judgment condition when executing the peak finding logic. The peak salience threshold is typically set to 1.5 to 2 times the fluctuation range of the hydraulic low-frequency baseband signal extracted during the no-load rotation phase. Only when the detected peak amplitude exceeds the surrounding base signal and reaches the set salience threshold is the peak determined as a valid material drop impact point. The state calibration module 20 extracts the absolute phase corresponding to the valid main peak and latches it as the reference material drop phase.

[0039] Considering the possibility of exceptionally viscous flowing materials in industrial settings, the state calibration module 20 is equipped with a calibration timeout tolerance mechanism. When the cumulative feed amount exceeds the feed quality threshold and a valid main peak satisfying the salience threshold is still not found, the state calibration module 20 proactively terminates the peak-finding process and retrieves historical calibration records of similar vehicles or a default empirical spatial phase from the system database as a backup reference drop phase, preventing the control program from experiencing a waiting deadlock. The reference drop phase physically maps the ideal drop point of the current batch of material in the absence of chute congestion, providing a spatial reference origin for subsequent determination of chute accumulation.

[0040] See attached document Figure 5 , Figure 5 This is a schematic diagram of a signal decoupling and corner domain conversion algorithm according to an embodiment of the present invention. In this embodiment, the signal decoupling module 30 receives time-aligned data output by the data acquisition module 10 and performs a physical feature-level stripping operation on the transient pressure signal. The original transient pressure signal physically combines the overall macroscopic load of the material inside the stirring drum with the instantaneous impact generated by the material falling onto the blade surface. The system uses dual-branch filtering separation processing to independently extract the two physical phenomena at different scales.

[0041] The signal decoupling module 30 is internally equipped with a digital filtering unit. The first branch extracts the low-frequency baseband pressure signal through a low-pass filter. To filter out the periodic pulsations caused by the rotation of the agitator, the cutoff frequency of the low-pass filter is usually set between 0.5 Hz and 1 Hz based on the rated rotation frequency of the agitator. The extracted low-frequency baseband pressure signal physically characterizes the overall weight and macroscopic viscous resistance of the material in the tank as it gradually increases during the feeding process. The second branch extracts the high-frequency pressure AC component through a band-pass filter. The lower cutoff frequency of the band-pass filter is aligned with the aforementioned low-pass cutoff frequency, and the upper cutoff frequency is set between 10 Hz and 12 Hz. The selection of the upper cutoff frequency is based on the fact that the idle speed to operating speed of the chassis engine of an engineering vehicle is usually in the range of 800 to 1200 rpm, corresponding to a mechanical vibration fundamental frequency of 13 Hz to 20 Hz. By strictly limiting the upper cutoff frequency below the mechanical vibration fundamental frequency of the chassis engine, unwanted frequency bands can be effectively blocked outside the passband, thereby completely eliminating the high-frequency mechanical noise generated by the chassis engine or hydraulic pump itself. The high-frequency pressure AC component mainly reflects the dynamic response caused by the impact of flowing material on the internal helical blades. For the design and discretization of the transfer function of the digital filter, those skilled in the art can use the conventional Butterworth filtering algorithm; its underlying design process is well-known in the field and will not be elaborated upon here.

[0042] After extracting the high-frequency pressure AC component, considering the slight fluctuations in rotational speed during actual operation of the mixing drum, direct signal analysis in the time domain would cause phase drift in the time axis due to material impact at the same spatial location. To establish a rigid spatial mapping relationship, the signal decoupling module 30, combined with the absolute phase angle signal synchronously acquired by the absolute encoder, converts the high-frequency pressure AC component in the time dimension into angular domain signals with equal angular intervals. As a preferred method, the signal decoupling module 30 uses a cubic spline interpolation algorithm to perform a resampling operation, setting the angular domain resolution to 0.5 degrees to 1 degree, thereby converting the data sequence independent variable from time to mechanical absolute angle. Physically, the resampling step rigidly binds the pressure pulsation to the specific spatial geometry of the mixing drum, ensuring that subsequent data processing is not disturbed by the underlying rotational speed instability.

[0043] Based on this, the signal decoupling module 30 performs a synchronous time averaging algorithm on the angular domain signals to calculate and output real-time angular domain pulse signals. The core logic of the synchronous time averaging algorithm lies in aligning the angular domain signals within multiple consecutive rotation cycles according to their mechanical phase and taking their arithmetic mean. This suppresses random disturbances that are asynchronous with the rotation cycle and highlights the material impact characteristics that are strongly correlated with the spatial position of the blades. The specific synchronous time averaging calculation formula is as follows: ; In the formula, In angular coordinates The real-time angular domain pulse signal value generated after synchronous time averaging; This indicates the number of whole rotation cycles involved in the averaging calculation, typically ranging from 3 to 5 cycles. This indicates the cumulative index of the rotation period currently participating in the summation calculation, with a value ranging from 1 to... Positive integers; This represents the high-frequency pressure AC component after angular domain conversion. Indicates in Up to 36 Absolute phase angle within a single period.

[0044] To prevent abnormal operating conditions from compromising the accuracy of the averaging calculation, the signal decoupling module 30 performs a valid verification of the operating status before executing the synchronous time averaging algorithm. The system monitors the differential rate of change of the absolute phase angle signal in real time. When an abnormal situation is detected, such as the stirring drum stopping, reversing, or a sudden change in angular velocity exceeding a set safety threshold, the signal decoupling module 30 actively removes data from the abnormal period and excludes it from the formula's accumulation term. To address the issue of insufficient effective periods after removing abnormal periods, the signal decoupling module 30 is equipped with a delay compensation mechanism. When the number of available periods is less than the set number of whole rotation cycles... During this process, the system automatically collects new rotation cycle data sequentially along the timeline until the required amount is accumulated. If not enough valid cycles are acquired within the set waiting time, the system will temporarily replace them with the real-time angular domain pulse signal generated in the previous valid time period to prevent subsequent calculations from entering a deadlock state due to missing input data. Through the above filtering and averaging processes, the system can output a smooth and accurate real-time angular domain pulse signal that reflects the impact characteristics of the material drop space, providing a data source for subsequent spatial offset calculations.

[0045] See attached document Figure 6 , Figure 6 This is a schematic diagram illustrating the principle of parametric calculation and multidimensional feature mapping according to an embodiment of the present invention. In this embodiment, the parametric calculation module 40 receives the real-time angular domain pulse signal and the low-frequency baseband pressure signal output by the signal decoupling module 30, and transforms the abstract digital signal into specific physical characteristic quantities representing the feeding state. The concrete feeding process involves the coupling of fluid mechanics and rigid body kinematics. It is difficult to describe the whole system using a single-dimensional signal. The parametric calculation module 40 establishes a multi-source parameter fusion calculation mechanism, providing a calculation center for the transition from low-level features to high-level control commands.

[0046] To address the material accumulation problem that easily occurs at the feed transition chute, the parameter calculation module 40 extracts the main peak of the real-time angular domain pulse signal in real time and obtains the transient peak phase corresponding to the main peak. From a physical mechanism perspective, when material stagnation and accumulation occur in the chute, the trajectory of the flowing material is obstructed by the bottom accumulation, causing spatial displacement and resulting in the final impact on the spiral blades inside the mixing drum deviating from the ideal landing point when there is no obstruction. Based on the above physical phenomenon, the system calculates the spatial offset between the transient peak phase and the reference falling phase latched in the internal register. Simultaneously, the parameter calculation module 40 performs time differential calculations on the data sequence of the weighing sensor to obtain the real-time discharge flow rate at the station. To quantify the severity of stagnation, the parameter calculation module 40 multiplies the spatial offset by the single-cycle angular domain energy integral and divides it by the real-time discharge flow rate to calculate the chute stagnation index. As a preferred method, the single-cycle angular domain energy integral is expressed as the area integral of the envelope of the angular domain pulse signal amplitude within the absolute phase angle range of 0 to 360 degrees. To prevent the program from crashing when the flow rate gradually approaches zero at the end of the feeding process, the parameter calculation module 40 adds a minimum positive constant to the denominator of the division operation for mathematical fallback. The value of the minimum positive constant usually corresponds to the minimum effective flow rate resolution of the weighing sensor at the station, and the setting range is 0.01 kJ / s to 0.05 kg / s, thereby ensuring the continuous operation of the control algorithm.

[0047] In assessing the remaining accepting capacity of the mixing tank, the parameter calculation module 40 extracts the mean and fluctuation range of the low-frequency baseband pressure signal within the real-time sliding time window. The mean reflects the total load of the current material, while the range characterizes the internal resistance fluctuations caused by changes in viscosity or slump decay. To eliminate calculation interference caused by differences in basic hydraulic resistance of different displacement vehicle models, the parameter calculation module 40 uses a pre-extracted no-load static pressure constant to differentially strip the above mean, and then performs dimensionless normalization calculations in conjunction with the maximum safe pressure extreme value set by the system to generate the volume tolerance parameter. The maximum safe pressure extreme value is set based on the physical factory protection pressure threshold of the hydraulic pump overflow valve of the engineering vehicle. The volume tolerance parameter dynamically indicates the tolerance boundary of the tank that can safely accept material without overflow or overload, and the parameter value shows a monotonically decreasing trend as the feeding action continues.

[0048] To prevent material waste caused by misalignment or accidental slippage of the vehicle chute, the parameter calculation module 40 establishes a set of spatial cross-equipment data self-verification logic. The parameter calculation module 40 calculates the time integral of the real-time discharge flow rate within a preset time segment. The time integral value of the discharge flow rate is physically equivalent to the actual mass of material released from the fixed-end mixing station. Simultaneously, the parameter calculation module 40 calculates the dynamic increment of the average low-frequency baseband pressure signal within the same time segment. The increment of the average pressure directly characterizes the physical property of the increased actual load on the mobile mixing truck. Under ideal leak-free handover conditions, due to the constraint of the law of conservation of mass, there is a positive mapping relationship between the mass released from the fixed end and the load increment perceived by the mobile end.

[0049] The parameter calculation module 40 calculates the dynamic ratio between the two, extracts the nonlinear mapping residual between the material release mass at the station end and the load increment at the vehicle end, and generates a material handover leakage prevention coefficient. The specific mathematical derivation logic is shown in the following formula: ; In the formula, This represents the material handover leak prevention coefficient calculated by the system. This represents the real-time feed rate obtained through differential calculation on the time axis; This represents the internal time independent variable in the integral calculation; Indicates the current observation time; This indicates the length of the observation time window used to assess leak-proof status, typically set to 5 to 10 seconds to smooth out short-term dynamic errors; This represents the mean value of the low-frequency baseband pressure signal at the current observation time. This represents the pre-calibrated and latched no-load static pressure constant of the system; This represents the system's preset ideal leak-free mass pressure mapping constant. Regarding the ideal leak-free mass pressure mapping constant... The parameter calculation module 40, within the stage where the cumulative feed amount does not exceed the initial feed quality threshold, records the ratio of the flow integral to the pressure increment at multiple discrete time points in real time, and calculates the arithmetic mean of all ratios, fixing the final arithmetic mean as a constant. In subsequent continuous monitoring calculations, under this physical scenario, the value of the fractional term at the front end of the calculation formula will increase rapidly, causing the material handover leakage prevention coefficient to exceed the preset mass conservation boundary condition.

[0050] To avoid arithmetic overflow anomalies caused by the denominator approaching zero due to the small increase in the average pressure during the initial feeding stage, the parameter calculation module 40 is configured with a start-up judgment condition before executing the above formula. Only when the average pressure signal of the low-frequency baseband... With no-load static pressure constant The parameter calculation module 40 only starts calculating the material transfer leakage prevention coefficient when the difference exceeds the preset hydraulic sensor noise threshold; otherwise, the default output of the material transfer leakage prevention coefficient is zero. Under normal feeding conditions, due to the precise entry of materials into the tank, various parameters follow physical proportions, and the material transfer leakage prevention coefficient fluctuates slightly around zero. When abnormal situations such as chute misalignment or guide shroud rupture occur, the station-end weighing sensor records a rapid accumulation of flow integral caused by a large amount of material loss, but the vehicle-end hydraulic system cannot sense the corresponding load increase. In this physical scenario, the value of the fractional term at the front end of the calculation formula will increase rapidly, causing the material transfer leakage prevention coefficient to exceed the preset mass conservation boundary condition. The parameter calculation module 40 converts physical leakage into quantifiable digital diagnostic features through spatial data cross-verification logic and outputs them to subsequent control links for mandatory intervention.

[0051] See attached document Figure 7 , Figure 7 This is a compensation execution control logic diagram according to an embodiment of the present invention. In this embodiment, the compensation execution module 50, as the end-effector of the control system, receives multi-dimensional feature parameters output by the parameter calculation module 40 and converts the abstract digital features into specific underlying mechanical drive commands, thereby realizing adaptive closed-loop control of the entire feeding process.

[0052] When processing the actual control logic, the compensation execution module 50 prioritizes the safety interlock determination. The compensation execution module 50 extracts the material handover leakage prevention coefficient output by the parameter calculation module 40 and compares it in real time with the preset safety handover threshold. The safety handover threshold is set based on the statistical variance distribution of the material handover leakage prevention coefficient under normal leak-free calibration conditions, typically taking three to five times the normal fluctuation variance as the judgment boundary, corresponding to a value range between 1.5 and 2.0. When the material handover leakage prevention coefficient exceeds the safety handover threshold, the system determines that a physical anomaly has occurred, such as material misalignment, chute offset, or flow guide component rupture. In this abnormal scenario, the compensation execution module 50 bypasses the conventional adjustment loop and simultaneously sends a highest-priority emergency cut-off command to the station-end discharge gate controller and the vehicle-end hydraulic pump controller via the vehicle communication bus, forcibly closing the discharge channel and stopping the mixing drum rotation. To prevent the control program from falling into a permanent deadlock state, the compensation execution module 50 will trigger the parking brake and illuminate the alarm indicator light after issuing an emergency cut-off command. The system will enter a protection lock mode until the operator completes on-site confirmation and inputs a reset command through the manual interaction terminal. Only then can the compensation execution module 50 be unlocked and its normal command output capability restored.

[0053] After eliminating serious leakage risks, to address the localized flow stagnation and accumulation issues caused by the viscosity of the material at the feed transition chute, the compensation execution module 50 introduces a chute retention index for dynamic speed compensation. When the chute retention index shows an upward trend, it indicates that the flowing material is accumulating at the tail of the chute, posing a risk of overflowing outwards. To accelerate the spiral entrainment and detachment of material into the mixing drum, the compensation execution module 50 superimposes a compensation speed increment positively correlated with the chute retention index on top of the system's preset base feed speed, thereby enhancing the internal blades' ability to tract and eject material.

[0054] While executing the acceleration command to alleviate localized accumulation, the system also considers the overall remaining volume of the mixing tank. As the feeding process continues, the available space inside the tank gradually decreases, and the overall material level continuously rises. If an excessively high rotational velocity is maintained at the end of the feeding process, the increased centrifugal force of the fluid may cause material to splash out of the feed hopper in the opposite direction. To prevent overload and overflow risks, the compensation execution module 50 uses a volume tolerance parameter to dynamically limit the target control speed. The specific integrated control law calculation formula is as follows: ; In the formula, This indicates the final target speed command output by the compensation execution module 50; This indicates the system's preset base feed speed, which is typically set to 10 to 12 revolutions per minute. This represents the pre-calibrated proportional gain compensation coefficient, used to adjust the physical sensitivity of the control system to material accumulation response; proportional gain compensation coefficient. The specific value is inversely proportional to the lead angle of the spiral blades inside the mixing drum and the vehicle's rated displacement. Vehicles with larger displacements usually have a smaller proportional compensation gain coefficient to avoid overloading the hydraulic system. This represents the chute retention index calculated and output by parameter calculation module 40; This indicates the maximum physical allowable speed of the hydraulic transmission system of the current vehicle model, which is usually set to 14 to 16 revolutions per minute based on the hydraulic motor displacement and the speed ratio of the reducer. This indicates the volume tolerance parameter generated by the parameter calculation module 40, with values ​​ranging from zero to one. This represents the extreme value determination function that takes the smaller of the two elements within the curly braces.

[0055] The above formula logically constructs a dual-track adjustment mechanism. When the volume tolerance parameter is close to one and there is ample space in the initial feeding stage, the system mainly relies on the front-end chute retention index to drive the acceleration logic, thereby improving feeding efficiency. As the volume tolerance parameter gradually approaches zero with the increase in feed volume, and the space becomes congested at the end of the feeding stage, the value of the back-end limiting term rapidly decreases and takes over system control, forcibly reducing the final target speed command, thus achieving a flexible deceleration at the end of the feeding stage.

[0056] After the final target speed command is generated, the compensation execution module 50 converts the digital command into a corresponding analog current signal or fieldbus message and sends it to the hydraulic system's electro-hydraulic proportional valve. For the closed-loop servo tracking and underlying electrical drive of the electro-hydraulic proportional valve, those skilled in the art can use conventional pulse width modulation drive circuits combined with proportional-integral-differential algorithms. Its hardware topology and underlying tracking logic are well-known technologies in the field and will not be elaborated upon here. Through multi-dimensional parameter dynamic constraints and feedforward adjustment, the control system can maintain good equipment coordination and throughput efficiency while ensuring the safety of the entire feeding process.

[0057] This embodiment selects a standardized concrete mixing plant of a large commercial concrete building materials production base as the fixed end, and a heavy-duty commercial vehicle chassis mixer truck with a rated mixing displacement of 12 cubic meters as the mobile end. In terms of hardware configuration, the station-end discharge gate is equipped with a high-precision weighing sensor and a pneumatic gate actuator, and the station-end main control unit adopts an industrial-grade programmable logic controller. A high-frequency dynamic pressure transmitter with a response frequency of up to 1000 Hz is installed at the pressure measurement interface of the vehicle-end closed hydraulic system, a high-resolution absolute encoder is coaxially installed at the input end of the mixing drum reducer, and the vehicle body is equipped with an on-board edge gateway supporting Time-Sensitive Networking Protocol (TSN). Communication between the station and the vehicle is established through a low-latency industrial wireless local area network deployed within the plant area. In terms of specific operating conditions, this experiment selected high-grade special concrete with low slump and high viscosity as the test material. This type of material is prone to accumulation and overflow at the transition chute during traditional feeding processes. The core system parameters are configured as follows: the discrete time step for data synchronization is set to 5 milliseconds; the time buffer depth is set to 200 milliseconds; the basic feed speed is set to 12 rpm; the maximum allowable high speed is set to 16 rpm; the maximum allowable interpolation interval threshold is set to 30 milliseconds; and the sliding window for the state calibration module 20 to extract the no-load static pressure constant is set to 3 complete rotation cycles.

[0058] To verify the superiority of the automatic compensation control system of this invention, a comparative test was designed. The control group adopted the industry-standard "constant speed control mode," in which the mixer truck was forced to maintain a constant speed of 12 rpm throughout the entire feeding cycle; the experimental group adopted the "multi-source parameter fusion and adaptive compensation control mode" of this invention. Under the same material ratio, the same target total feed mass (approximately 28 tons), and the same ambient temperature, each group underwent 50 repeated feeding tests, and the key core indicators were statistically averaged. The specific experimental test data are shown in Table 1. Table 1: Comparison of the effects of traditional constant speed control and the adaptive compensation control of this invention

[0059] Experimental conclusion: Reference Appendix Figure 8 With appendix Figure 9 The feeding efficiency and anti-accumulation capabilities are significantly improved. In the early stages of feeding, when the system detects that viscous materials are causing a rapid increase in the chute retention index, the adaptive compensation control system can react quickly, adding a positive compensation increment on top of the base feeding speed, actively increasing the speed of the mixing drum. This dynamic acceleration greatly enhances the material intake and entrainment capabilities of the internal spiral blades, not only completely breaking through the material accumulation bottleneck at the tail of the chute, but also reducing the overall feeding time by nearly 18%.

[0060] The safety constraint effect at the limit volume edge is excellent. As the feeding process enters its final stage, the system's volume tolerance parameter exhibits a significant monotonic decreasing trend as the target load approaches. When this parameter falls below the safety warning threshold, the back-end extreme value limiting logic strongly intervenes, forcibly taking over system control and reducing the target rotational speed. This flexible speed reduction mechanism completely avoids material backflow and overflow caused by excessive rotational speed and centrifugal force at the end of the feeding process, achieving zero overflow rate.

[0061] Third, the cross-equipment leakage monitoring mechanism is extremely sensitive. In simulated abnormal experiments targeting chute misalignment or guide shroud rupture, the system, through cross-verification logic of station-end flow integral and vehicle-end pressure increment, captures the sudden change in mass mapping residual the instant material leakage occurs. The leakage prevention coefficient quickly exceeds the boundary conditions, and the system triggers the highest level of emergency interlock cutoff within 1.5 seconds, simultaneously closing the gate and stopping the mixing drum, successfully minimizing material waste and on-site environmental pollution.

[0062] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automatic compensation control system and method for the feed flow rate of a concrete mixer truck, comprising a mixing plant equipped with a discharge gate and a weighing sensor, and a mixer truck equipped with a dynamic pressure transmitter and an absolute encoder, characterized in that, include: The data acquisition module is used to synchronously acquire weight signals, transient pressure signals, and absolute phase angle signals and perform time axis alignment. The state calibration module is used to extract the no-load static pressure constant during the no-load stage and the reference material dropping phase during the initial feeding stage. The signal decoupling module is used to separate transient pressure signals to extract low-frequency baseband pressure signals and combine high-frequency pressure AC components with absolute phase angle signals to convert them into real-time angular domain pulse signals. The parameter calculation module is used to calculate the chute retention index based on the real-time angle domain pulse signal, the reference material dropping phase and the weight signal, calculate the volume tolerance parameter based on the low-frequency baseband pressure signal and the no-load static pressure constant, and calculate the material transfer leakage prevention coefficient based on the weight signal and the low-frequency baseband pressure signal. The compensation execution module is used to adjust the stirring drum speed by superimposing the compensation speed increment based on the chute retention index and using the volume tolerance parameter to execute the speed limit; when the material transfer leakage prevention coefficient exceeds the set boundary, it drives the discharge gate to close and stops the stirring drum.

2. The automatic compensation control system and method for the feed flow rate of a concrete mixer truck according to claim 1, characterized in that, The specific logic for the data acquisition module to perform rigid time axis alignment is as follows: A time buffer pool with a preset capacity is established; the weight signal, transient pressure signal, and absolute phase angle signal carrying timestamps are stored in the time buffer pool; the timestamps are parsed within the time buffer pool, and the weight signal, transient pressure signal, and absolute phase angle signal carrying the same timestamp are bound to a data set of the same sampling time; when some data are not strictly aligned according to the set discrete time steps, the maximum allowable interpolation interval threshold is checked; if the maximum allowable interpolation interval threshold is not exceeded, a linear interpolation algorithm is used in conjunction with the actual acquired value of the transient pressure signal corresponding to the actual sampling timestamp to perform time axis alignment compensation calculation.

3. The automatic compensation control system and method for the feed flow rate of a concrete mixer truck according to claim 1, characterized in that, The specific logic for the state calibration module to extract the no-load static pressure constant is as follows: during the no-load rotation stage when the feeding program is started and the discharge gate is closed, a sliding time window covering the preset cycle of continuous constant speed rotation of the mixing drum is set; the low-frequency baseband pressure signal within the sliding time window is subjected to summation and averaging processing to calculate and generate the no-load static pressure constant characterizing the hydraulic internal resistance.

4. The automatic compensation control system and method for the feed flow rate of a concrete mixer truck according to claim 1, characterized in that, The specific logic for the state calibration module to extract the reference dropping phase is as follows: within the time interval during which the cumulative feed amount does not exceed the set feed quality threshold, locate the main peak of the angular domain pulsation signal; when the detected peak amplitude exceeds the surrounding base signal and reaches the set salience threshold judgment condition, determine that the detected peak is an effective dropping impact point; extract the absolute phase corresponding to the effective dropping impact point as the reference dropping phase.

5. The automatic compensation control system and method for the feed flow rate of a concrete mixer truck according to claim 1, characterized in that, The specific logic of the signal decoupling module in generating real-time angular domain pulse signals is as follows: low-frequency baseband pressure signals are extracted through a low-pass filter, and high-frequency pressure AC components are extracted through a band-pass filter; a cubic spline interpolation algorithm is used to perform resampling operations to convert the high-frequency pressure AC components in the time dimension into angular domain signals with equal angular intervals; the angular domain signals in multiple consecutive rotation cycles are aligned according to the mechanical absolute phase and the arithmetic mean is taken to calculate and output the real-time angular domain pulse signal after suppressing asynchronous disturbances.

6. The automatic compensation control system and method for the feed flow rate of a concrete mixer truck according to claim 1, characterized in that, The specific logic of the parameter calculation module for calculating the chute retention index and volume tolerance parameters is as follows: extract the transient peak phase of the real-time angular domain pulse signal; calculate the spatial offset between the transient peak phase and the reference discharge phase; and perform time differential calculation on the weight signal output by the weighing sensor to obtain the real-time discharge flow rate. The chute retention index is calculated by multiplying the spatial offset by the single-cycle angular domain energy integral and dividing by the real-time feed rate. The mean value of the low-frequency baseband pressure signal within the real-time sliding time window is extracted. The mean value of the low-frequency baseband pressure signal is differentially stripped using the no-load static pressure constant. Dimensionless normalization calculation is then performed in conjunction with the maximum safe pressure extreme value set by the system to generate the volume tolerance parameter.

7. The automatic compensation control system and method for the feed flow rate of a concrete mixer truck according to claim 1, characterized in that, The specific logic for calculating the material handover leakage prevention coefficient by the parameter calculation module is as follows: calculate the time integral value of the real-time feeding flow rate within a preset time segment; synchronously calculate the dynamic increment of the average low-frequency baseband pressure signal within the same time segment; calculate the dynamic ratio of the time integral value to the dynamic increment, extract the nonlinear mapping residual between the mass of material released from the fixed end and the load increment of the moving end, and generate the material handover leakage prevention coefficient; and is configured with a start-up judgment condition: when the difference between the average low-frequency baseband pressure signal and the no-load static pressure constant is greater than the preset noise floor threshold, the calculation logic for the material handover leakage prevention coefficient is started.

8. The automatic compensation control system and method for the feed flow rate of a concrete mixer truck according to claim 1, characterized in that, The specific logic for the compensation execution module to generate the comprehensive target speed command is as follows: set the basic feed speed, the proportional compensation gain coefficient, and the maximum speed limit; add the product of the basic feed speed and the proportional compensation gain coefficient multiplied by the chute retention index to generate the first speed target; multiply the maximum speed limit by the volume tolerance parameter to generate the second speed target; and select the smaller value between the first speed target and the second speed target as the final comprehensive target speed command output.

9. The automatic compensation control system and method for the feed flow rate of a concrete mixer truck according to claim 1, characterized in that, The specific logic of the compensation execution module to prevent material leakage is as follows: the material handover leakage prevention coefficient is compared with the preset safe handover threshold in real time; when the material handover leakage prevention coefficient is greater than the safe handover threshold, it is determined that an abnormality has occurred in the physical space; bypassing the conventional adjustment circuit, the highest priority emergency cut-off command is sent synchronously to the concrete mixing plant and concrete mixer truck through the communication network, forcibly closing the discharge gate and cutting off the rotation power of the mixing drum, and triggering the parking brake to enter the protection lock mode until the manual input reset command is received to unlock the state.

10. A method for automatic compensation control of feed flow rate of a concrete mixer truck, applied to the automatic compensation control system for feed flow rate of a concrete mixer truck as described in any one of claims 1-9, characterized in that, Includes the following steps: Based on a precise time protocol, the weight signal output by the weighing sensor, the transient pressure signal output by the dynamic pressure transmitter, and the absolute phase angle signal output by the absolute encoder are synchronously acquired, and a timestamp is added to the acquired data for rigid alignment of the time axis. In the no-load rotation stage, the average value of the low-frequency baseband pressure signal is extracted as the no-load static pressure constant, and in the initial feeding stage, the absolute phase corresponding to the peak value of the angular domain pulsation signal is extracted as the reference dropping phase. The transient pressure signal is filtered and separated to independently extract the low-frequency baseband pressure signal and the high-frequency AC pressure component. The high-frequency AC pressure component is converted into an angular domain signal by combining the absolute phase angle signal and the real-time angular domain pulse signal is calculated and output. The chute retention index is calculated based on the real-time angle domain pulse signal, the reference material dropping phase, and the weight signal. The volume tolerance parameter is calculated based on the low-frequency baseband pressure signal and the no-load static pressure constant. The material transfer leakage prevention coefficient is calculated based on the weight signal and the low-frequency baseband pressure signal. Based on the system's preset basic feed speed, a compensation speed increment that is positively correlated with the chute retention index is superimposed. At the same time, the target speed is constrained by the volume tolerance parameter, and a comprehensive target speed command is generated to adjust the feed speed of the mixing drum. Furthermore, when the material transfer leakage prevention coefficient exceeds the preset mass conservation boundary condition, the discharge gate is simultaneously driven to close and the rotation of the mixing drum is stopped.

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