An intelligent traffic light control system and method for downhole

Abstract

The present application relates to the field of traffic signal control, and particularly relates to an underground intelligent traffic light control system and method. An underground intelligent traffic light control method comprises the following steps: when the traffic light is in a road intersection prohibition phase, a traffic light signal containing a next traffic time period is broadcast to a roadway, and response information fed back by a vehicle is received, the response information comprising a vehicle identity, and vehicle position information when the vehicle receives the traffic light signal. The present application solves the problems of serious signal attenuation and large visual interference of drivers in the underground by dynamically matching signal transmission intensity and vehicle distribution, ensures stable signal reception by vehicles at a long distance, prolongs reaction time, and reduces the risk of red light running and collision; meanwhile, energy saving and consumption reduction, computing power optimization and intersection adaptive regulation and control are also achieved, and the safety, reliability and control efficiency of underground traffic operation are comprehensively improved.

Description

Technical Field

[0001] This invention relates to the field of traffic signal control, and in particular to an intelligent traffic light control system and method for underground mines. Background Technology

[0002] As underground mining operations expand, the frequency and density of underground vehicle transport have increased significantly. Traffic lights are used at underground intersections to maintain order in each lane. Traditionally, the cycle time of these traffic lights is manually set to a fixed value by staff based on traffic conditions at the intersection. However, actual traffic flow at intersections is not constant, and the level of congestion differs significantly between peak and off-peak hours. A fixed traffic light duration easily leads to an imbalance in traffic flow, with some lanes experiencing sparse traffic while others are congested and queuing.

[0003] To address the aforementioned shortcomings, existing technologies attempt to collect and analyze vehicle traffic data to infer the traffic light operating cycle to adapt to on-site conditions. This allows the traffic light duration to dynamically adapt to real-time traffic conditions at the intersection, effectively improving the rationality of traffic light duration configuration and enhancing underground vehicle traffic efficiency. For example, Chinese patent application CN110738863A discloses a method for determining the traffic light cycle. This method collects data on the stop time of vehicles passing through the intersection, calculates the coefficient of variation of the time remainder for each candidate cycle by traffic direction, and combines this with directional weights to determine the comprehensive coefficient of variation. Finally, it selects the candidate cycle with the smallest coefficient of variation as the traffic light operating cycle. This method can match traffic flow characteristics to a certain extent and improve the adaptability of traffic signals.

[0004] However, the environment in underground tunnels differs significantly from surface traffic scenarios. The complex topology and narrow, enclosed spaces of underground tunnels mean that traffic light signals are easily attenuated by surrounding rock, dust, and humidity, often requiring vehicles to be very close to intersections to effectively receive the signals. Furthermore, underground environments generally suffer from insufficient lighting and high dust concentrations, causing drivers to experience visual impairment near intersections due to dim light and dust, again requiring them to be close to the traffic lights for clear observation. The combined effect of delayed traffic light reception and limited driver visual recognition significantly reduces reaction time, greatly increasing the risk of vehicles illegally entering intersections during prohibited phases, leading to emergency braking and even collisions, thus significantly increasing the operational risks of underground traffic. Summary of the Invention

[0005] This invention provides an intelligent traffic light control system and method for underground mines to solve the problems of severe traffic light signal attenuation and significant visual interference for drivers in underground roadways, which lead to high risks in underground traffic operations.

[0006] To solve the above-mentioned technical problems, this application provides the following technical solution: A method for controlling intelligent traffic lights in underground mines includes the following steps: When the traffic light is in the prohibited phase at the intersection, a traffic light signal containing the next permitted time period is broadcast into the alleyway. At the same time, response information from vehicles is received. The response information includes the vehicle's identification and the vehicle's location information when it received the traffic light signal. The response information, the broadcast time of the corresponding traffic light signal, and the signal transmission strength are used as historical data. Based on the signal transmission strength and vehicle location information in historical data, the coverage area corresponding to different signal transmission strengths is marked in the preset lane map; the number distribution of vehicles at different times in the preset lane map is statistically analyzed from historical data; at the same time, the driving speed of vehicles at different locations in the preset lane map is obtained based on the vehicle location information and vehicle identification in the response information; the driving speed and the number distribution are correlated to obtain the first correlation relationship. Based on vehicle identification data from historical data, the time from when a vehicle receives a traffic light signal to when it arrives at the corresponding intersection is obtained as the transit time. At the same time, the time interval between when the vehicle passes through the intersection and the start of the next passage time period is obtained as the restricted transit time. The minimum transit time when the restricted transit time is no greater than the preset minimum restricted transit time is statistically analyzed, and the minimum transit time is associated with the corresponding intersection. Obtain the response information corresponding to the currently broadcast traffic light signal, count the number distribution of vehicles at each location on the preset lane map, obtain the vehicle speed at each location by combining the first correlation, obtain the time taken for vehicles at each location to travel to the corresponding intersection by combining the distance between each location and the intersection corresponding to the traffic light, and use the comparison time as the comparison range; use the coverage area formed by the location of the vehicles corresponding to the comparison time on the preset lane map as the comparison range. The current traffic light signal is broadcast in the preset lane map with the maximum signal transmission intensity within the reference range.

[0007] The basic principle and beneficial effects of this invention are as follows: This invention broadcasts a signal containing the next passage time period during the traffic light prohibition phase and collects vehicle response information. It uses historical data to construct a correlation between signal coverage area marking, vehicle speed and quantity distribution, and key passage time at intersections. Then, it combines current vehicle response data to deduce arrival time at the intersection and determine the signal coverage comparison range. Finally, it broadcasts a signal with the maximum transmission intensity within this range. To address the issues of signal attenuation and visual interference in underground manholes, it dynamically matches signal transmission intensity with vehicle distribution to ensure that vehicles receive clear signals at a sufficiently long distance, reducing insufficient reaction time caused by signal reception delays. At the same time, it compensates for the recognition shortcomings caused by driver visual impairments, thereby reducing the risk of vehicles illegally entering intersections.

[0008] This invention broadcasts the next permitted passage time at an intersection to vehicles within the tunnel during restricted traffic periods. Drivers can then plan their driving pace accordingly, smoothly arriving at the intersection and decelerating before the permitted passage time begins, making them more inclined to proceed slowly through the intersection area. As vehicles approach the intersection, drivers can gradually observe the actual status of the traffic lights, allowing them to make driving decisions more suited to the current driving environment. If only the current restricted or permitted traffic status is broadcast, drivers at locations far from the intersection where the light status is difficult to clearly discern are prone to misjudging distance, making them more likely to rush into the intersection near the end of the permitted passage time, significantly increasing the risk of illegally entering the intersection. Broadcasting the next permitted passage time during restricted traffic periods provides drivers with sufficient time to decelerate and anticipate even when the light status cannot be clearly observed, alleviating the psychological pressure caused by untimely information acquisition and a tight passage window. This effectively reduces the probability of vehicles illegally entering intersections from the perspective of driving behavior and decision-making logic, improving the safety of underground traffic.

[0009] The dynamic control of signal transmission strength does not adopt a fixed power mode, but precisely matches the maximum transmission strength according to the actual distribution range of vehicles. It only strengthens the signal output in the effective area where vehicles pass, tightens the signal radiation boundary, avoids the unlimited spread of high-power signals, prevents the overlap of traffic signals at multiple intersections in the mine and electromagnetic crosstalk, and at the same time improves the anti-interference capability of the signal at the target area, weakens the impact of noise generated by various electromechanical equipment in the tunnel, avoids energy waste and large-scale communication interference caused by excessive power, and avoids insufficient signal coverage caused by insufficient power. It effectively saves energy costs while ensuring communication effect, which is in line with the actual scenario of relatively limited energy supply and complex electromagnetic environment in the mine.

[0010] The collection and analysis of vehicle response information in this invention forms a data-driven control mechanism. When the traffic flow is high, the vehicle density in the corresponding tunnel is high, and the number of response information is naturally large. When the traffic flow is low, the number of response information is relatively small. There is no need to perform redundant calculations on sparse data. The computing power is concentrated on scenarios with dense vehicles and more urgent communication needs, which not only improves the computing efficiency but also reduces the consumption of ineffective computing power, making signal control decisions more timely and reliable, which meets the control needs of highly dynamic changes in underground traffic.

[0011] By establishing a correlation between vehicle speed and quantity distribution based on historical data, the arrival time of vehicles at intersections can be accurately predicted, making the determination of traffic light signal coverage more targeted. This avoids the problem of signal coverage being too wide or too narrow, ensuring that vehicles in different locations can receive traffic light signals at an appropriate distance. Especially in situations where underground tunnels are narrow and vehicle avoidance space is limited, this further improves the orderliness of traffic flow and reduces the probability of emergency braking and collision accidents.

[0012] The design that links the minimum transit time to the corresponding intersection provides a historical reference for traffic light signal control. It can accurately adjust the signal transmission strategy according to the traffic characteristics of different intersections, adapt to the topological differences of different tunnel sections underground, avoid the problem of insufficient adaptability caused by unified control, and make traffic light signal control more in line with the complex and ever-changing tunnel environment underground, further enhancing the safety and stability of traffic operation.

[0013] In summary, this invention solves the problems of severe signal attenuation and significant visual interference for drivers in underground mines by dynamically matching signal transmission strength with vehicle distribution. This ensures stable signal reception for vehicles over long distances, extends reaction time, and reduces the risk of running red lights and collisions. At the same time, it also achieves energy saving, computing power optimization, and adaptive control at intersections, comprehensively improving the safety, reliability, and management efficiency of underground traffic operations.

[0014] Furthermore, when the distance between the vehicle's location information in the response message and the corresponding intersection is not less than the preset minimum deceleration distance, the vehicle's speed is continuously monitored through the vehicle's identification identifier. If the vehicle's speed does not decrease, the start time of the next passage period is postponed, and the duration of the next passage period is used as a reference duration. If the vehicle's speed decreases within the reference duration, the start time of the next passage period is restored to the time before the postponement. If the vehicle's speed still does not decrease, the start time of the next passage period remains unchanged. When postponing the start time of the next passage period, the deceleration duration is calculated based on the difference between the vehicle's current speed and the preset intersection passage speed, as well as the preset deceleration acceleration, and then the start time of the next passage period is postponed by the deceleration duration.

[0015] By monitoring the vehicle's speed when it is at least the minimum deceleration distance from the intersection and dynamically extending the passage time, the deceleration preparation period can be extended when the vehicle has not decelerated, preventing vehicles from forcibly crossing the road due to signal attenuation or poor visibility and the inability to judge the light status in time. The setting of the reference time ensures the accuracy of deceleration behavior recognition and avoids frequent fluctuations in the passage time. It is especially suitable for scenarios where the driver's vision is obstructed at the turn of the alley and it is difficult to observe the intersection in advance, reducing the risk of illegal entry and emergency braking from the perspective of time control.

[0016] Furthermore, the intersection includes traffic light signals with multiple phases. When the traffic light is in the phase where passage is permitted, a deceleration signal is sent to the vehicles during the deceleration period before the end of the passage time, and deceleration feedback information from the vehicles in response to the deceleration signal is received. The deceleration feedback information includes vehicle position information. The trend of vehicle speed change is analyzed based on the vehicle position information and the sending time of the deceleration feedback information. If the vehicle speed does not decrease, the start time of the next passage period in other phases of the traffic light signals at the corresponding intersection is postponed.

[0017] By accurately calculating the deceleration time based on the speed difference and deceleration acceleration, the delay in passage time is matched with the actual deceleration needs of vehicles, avoiding excessive or insufficient delay time. In multi-phase intersections, the release time of other phases can be adjusted in conjunction with vehicles that have not decelerated, which can reduce conflicts between intersecting lanes. This is particularly suitable for scenarios with limited space for vehicle convergence at narrow intersections in underground mines, improving the safety and orderliness of multi-lane coordinated passage.

[0018] Furthermore, before adjusting the start time of the next passage period, the driving speed of all vehicles in the same road segment is counted in the preset lane map based on the vehicle location information, and the changing trend of the driving speed of all vehicles is analyzed; if the proportion of vehicles with the same changing speed exceeds the preset same-direction threshold, the start time of the next passage period remains unchanged.

[0019] By statistically analyzing the speed change trends of vehicles on the same road segment, the system avoids erroneous adjustments to the overall signal due to abnormal conditions of a single vehicle, thereby improving the reliability of the control. In densely trafficked road sections, it can reduce ineffective control and lower computing power consumption. It is suitable for scenarios with concentrated traffic flow and strong signal interference during peak underground operations, ensuring that the traffic light control strategy is stable and adaptable to the driving conditions of the group.

[0020] Furthermore, if the vehicle speed does not decrease after the start time of the next passage period is postponed, the vehicle location information will be used to determine whether there is a vehicle in front of the vehicle. If there is a vehicle in front, and the distance between the vehicle and the vehicle in front calculated based on the vehicle speed is greater than the preset safe braking distance, a lane change or deceleration prompt will be sent to the vehicle in front based on the vehicle location information.

[0021] Within a safe braking distance, guiding the vehicle in front to change lanes creates a natural driving reference and speed constraint for the following vehicle. The vehicle in front, being closer to the following vehicle than the ambient light, provides a clear, close-range visual reference, effectively mitigating the visual difficulties caused by insufficient lighting and dust interference underground. This creates a safer following environment, prompting the following vehicle to proactively reduce its speed and regulate its trajectory. In environments with clear visibility on the ground, where road conditions are readily apparent, a failure to slow down by the following vehicle could pose a collision risk, requiring the leading vehicle to actively avoid a collision. However, underground, with poor visibility and visibility conditions, guiding the vehicle in front to form a following reference can simultaneously ensure orderly deceleration and safe driving for multiple vehicles, thereby improving the safety and controllability of traffic in underground intersection areas.

[0022] Furthermore, the traffic light signal also includes intersection entrance information; the preset lane map pre-stores the mapping relationship between intersection entrance lanes and corresponding intersection exit lanes; when the traffic light is in the open state, vehicles passing through the corresponding intersection are regarded as relay vehicles, and the exit lane corresponding to the relay vehicle's travel path is regarded as the relay lane; the relay vehicle uses the traffic light signal corresponding to the relay lane as the relay signal, and when the reception strength of the relay signal is greater than the preset short-range strength, it receives and stores the relay signal; after the relay vehicle enters the relay lane, it broadcasts the relay signal before the start time of the next open time period corresponding to the relay signal.

[0023] This invention utilizes vehicles that have already passed through intersections as relay vehicles to forward traffic light signals. This effectively overcomes the signal attenuation problems caused by surrounding rock obstructions and enclosed spaces in underground roadways, expanding signal coverage. Due to the demands of mining operations, underground roadways have many branches and work sites are scattered. Transport vehicles frequently travel between material yards and mining faces. Furthermore, during shift changes and peak material transport periods, localized traffic congestion is common, while traffic is sparse during non-operational periods, creating a naturally uneven traffic flow. The relay method of this invention can specifically provide clearer and more reliable signals to vehicles at distant work sites and in areas with sparse traffic. Simultaneously, by diverting signal transmission tasks, it reduces the communication load and computational pressure on traffic lights in multi-branch roadways and uneven traffic scenarios, allowing distant vehicles to obtain their next passage time in advance. This provides drivers with sufficient time to decelerate and make judgments, significantly improving traffic safety in adverse visual environments.

[0024] Furthermore, the traffic light signal includes the communication address of the traffic light; after receiving the relay signal, the relay vehicle sends a carrying signal to the traffic light according to the communication address; at the start time of the next passage time corresponding to the relay signal, the relay vehicle sends a carrying end signal to the traffic light according to the communication address; after receiving the relay signal, the vehicle sends a response information to the traffic light according to the communication address.

[0025] After receiving the relay signal, the relay vehicle sends a signal based on the communication address, which can promptly wake up traffic lights in a low-power state, enabling them to respond quickly and prepare for subsequent timing control. At the start of the next traffic period, it sends a signal to end the relay task, accurately informing the traffic light that the relay task is complete and facilitating the timely resumption of normal control logic. Other vehicles, upon receiving the relay signal, also provide feedback based on the communication address, allowing the traffic lights to monitor the reception status of remote vehicles in real time. This method significantly improves communication reliability in complex underground tunnel environments, enabling traffic lights to be woken up on demand, precisely controlled, and terminated promptly. It reduces the energy consumption and computational burden of continuous traffic light broadcasting while ensuring real-time and efficient signal scheduling, significantly improving the stability and response speed of traffic control in harsh environments.

[0026] Furthermore, after receiving the carried signal, the traffic light stops broadcasting the traffic light signal until it receives a signal indicating the end of the carried signal or a response message.

[0027] Traffic lights stop actively broadcasting after receiving a signal until they receive a signal indicating the end of signal transmission or a response. This reduces redundant signal transmission, lowers electromagnetic interference in the roadway, and reduces equipment energy consumption, making traffic light signal transmission more orderly and pure, and further improving the stability of vehicle reception of traffic light signals.

[0028] Furthermore, the traffic lights statistically analyze the reception frequencies of the carried signals and response information received at different times. Based on the differences in the distribution of the carried signal reception frequencies and response information reception frequencies over time, the start time of the next passage period for the traffic lights corresponding to the relay signals is adjusted. At the same time, the signal transmission frequency and signal transmission strength of the broadcast relay signals are adjusted according to the carried signal reception frequencies.

[0029] Traffic lights can accurately determine the real-time traffic density of each lane by statistically analyzing the reception frequencies of signal-carrying and response information and comparing their distribution differences over time. When the traffic flow in the relay lane is high and the traffic flow in the opposite lane is low, the start time for the opposite lane to proceed can be appropriately delayed, extending the passage time of the relay lane. This prioritizes the efficient passage of dense traffic through the intersection, avoiding congestion and racing. Simultaneously, the transmission frequency and strength of the relay signal are dynamically adjusted based on the signal reception frequency, reasonably controlling the number of vehicles participating in the relay. This ensures effective signal coverage for distant vehicles while avoiding channel congestion and interference caused by a large number of vehicles broadcasting simultaneously. In this way, the traffic light control strategy is matched in real-time with the complex traffic flow underground, improving intersection efficiency and safety, optimizing communication resource utilization, and ensuring stable and reliable transmission of relay signals. Attached Figure Description

[0030] Figure 1 This is a flowchart of an intelligent traffic light control method for underground mines in Example 1. Detailed Implementation

[0031] The following will describe the concept and technical effects of the present invention clearly and completely with reference to embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention. Example 1 like Figure 1 As shown, an intelligent traffic light control method for underground mines includes the following steps: When the traffic light is in the prohibited phase at the intersection, a traffic light signal containing the next permitted time period is broadcast into the alleyway. At the same time, response information from vehicles is received. The response information includes the vehicle's identification and the vehicle's location information when it received the traffic light signal. The response information, the broadcast time of the corresponding traffic light signal, and the signal transmission strength are used as historical data.

[0032] After receiving the traffic light signal, the vehicle sends back information to the traffic light including its unique identifier (UUID encoding is used in this embodiment, which is preset by the vehicle when it leaves the factory), the current lane, and the real-time location coordinates.

[0033] Traffic light broadcasts include traffic light signals for prohibited phases, lanes, and the next permitted time period. Vehicles use their own positioning combined with a preset lane map to match their lane, and then, based on the phase status of the corresponding lane in the signal, they provide feedback information including their own identity, lane, and real-time location, thus forming precise two-way communication between the vehicle and the lights.

[0034] The traffic light is equipped with an industrial-grade microcontroller as its core computing unit, which has multi-tasking capabilities and supports calculations such as historical data storage, grid vehicle statistics, speed / duration calculation, and correlation fitting. It is equipped with a communication module, which adopts a LoRa wireless communication module to ensure long-distance signal broadcasting with vehicles, reception of response information, and data transmission stability. It is supplemented by a storage module to retain historical data, preset parameters, and map information, and is equipped with a power management module (in this embodiment, a wide voltage input power management module) to adapt to the underground power supply environment and ensure continuous and stable operation.

[0035] Based on historical data of signal transmission strength and vehicle location information, the coverage areas corresponding to different signal transmission strengths are marked in a preset tunnel map (digitally constructed by the administrator based on geographic survey data of actual underground tunnel topology, intersections, and lanes, with pre-stored coordinates, lane attributes, and entrance / exit lane mapping relationships, and can be updated as needed). The distribution of vehicle numbers at different locations on the preset tunnel map at different times is statistically analyzed from historical data. Simultaneously, based on vehicle location information and vehicle identification in the response information, the driving speed of vehicles at each location on the preset tunnel map is obtained. A correlation analysis is performed between driving speed and number distribution to obtain the first correlation relationship. The first correlation relationship is a fitted correlation between the number of vehicles in each grid of the preset tunnel map and the driving speed of vehicles in that grid, used to quickly match the corresponding driving speed based on the real-time vehicle number.

[0036] When analyzing the distribution of vehicle numbers at different locations on a pre-defined tunnel map at different times, the historical data of vehicle location information and signal reception time is first cleaned. During cleaning, data with location information outside the pre-defined tunnel map range or with empty reception times are removed. Then, data with duplicate vehicle locations or abnormal speeds (e.g., >20km / h; this threshold is based on underground vehicle safety driving regulations and can be adjusted by the administrator according to tunnel slope, width, and other working conditions) are filtered out, retaining valid location and time information. The pre-defined tunnel map is divided into fixed grids and labeled with coordinates. In this embodiment, the default grid size is set to 4m×4m, which can be adjusted by the administrator according to the tunnel width. Each grid is labeled with a unique number and center coordinates. The vehicle location of each data point is then matched to the corresponding grid, categorized by time dimension (e.g., minutes, the time interval can be adjusted according to traffic density). Finally, the number of vehicle identification tags appearing in each grid within each time interval is counted, which represents the number of vehicles in that grid and for that time period. Finally, using time as the dimension, the same vehicle identification mark appearing multiple times within the same time interval is counted only once, forming the vehicle quantity statistics for each grid. This intuitively presents the quantity distribution of vehicles at different locations on the alley map at different times, providing a data foundation for subsequent correlation analysis.

[0037] When obtaining the vehicle's speed at various locations on a preset lane map, the distance traveled by the vehicle is obtained based on its position change on the map, and the vehicle's speed is calculated using the time elapsed during the position change. In this embodiment, the vehicle's distance is calculated using a two-point coordinate distance formula, and the speed is determined by combining the time difference between preceding and following time points. A conversion factor is used to standardize the speed unit. If the vehicle's position does not change, it is considered stationary, and the speed is recorded as zero.

[0038] Based on vehicle identification data from historical data, the time from when a vehicle receives a traffic light signal to when it arrives at the corresponding intersection is obtained as the transit time. At the same time, the time interval between when the vehicle passes through the intersection and the start of the next passage time period is obtained as the restricted transit time. The minimum transit time when the restricted transit time is no greater than the preset minimum restricted transit time is statistically analyzed, and the minimum transit time is associated with the corresponding intersection.

[0039] The minimum restricted driving time is calculated by taking the underground vehicle speed limit (set by the administrator) as the initial speed, and combining the underground road surface friction coefficient and vehicle braking performance. The shortest braking time from the speed limit to a standstill is calculated by dividing the initial speed by the vehicle's maximum braking deceleration. Then, a 0.5-1 second (set by the administrator based on the driver's reaction time) safe buffer time at the intersection is added. The sum of the two is the minimum restricted driving time, which ensures that vehicles can stop safely at the speed limit and avoids collisions caused by rushing through intersections.

[0040] The system retrieves the response information corresponding to the currently broadcast traffic light signal, statistically analyzes the distribution of vehicle numbers at various locations on a preset lane map, and obtains the vehicle speed at each location based on the first correlation relationship (vehicle number vs. driving speed fitting relationship). It then uses the distance between each location and the corresponding intersection of the traffic light to determine the travel time from each location to the intersection as a reference time. The coverage area formed by the locations of vehicles corresponding to the reference time on the preset lane map is used as the reference range.

[0041] The reference range is the area formed by the vehicle positions in the preset lane map corresponding to the reference time of all vehicles traveling to the corresponding intersection, which is used to limit the coverage boundary of the signal transmission strength.

[0042] Specifically, firstly, all response information corresponding to the current traffic light signal is extracted. Following the grid division rules of the preset tunnel map, the number of vehicles in each grid is counted to form a real-time location distribution. Next, the established first correlation (vehicle quantity and speed fitting relationship) is invoked, and a linear regression algorithm is used to construct a speed fitting formula. The number of vehicles in the grid is used as a variable, and the speed is calculated by combining the fitting coefficient and a constant. The fitting coefficient is negatively correlated, indicating that the more vehicles there are, the lower the speed. The relevant parameters are determined by historical data, can be dynamically updated in real time, and stored locally. Inputting the number of vehicles in each grid matches the vehicle speed at the corresponding location. Then, the straight-line distance between the center of each grid and the intersection corresponding to the traffic light is extracted from the preset tunnel map as the travel distance. The single-grid reference time is calculated as "travel distance ÷ corresponding location travel speed". If the vehicle speed is 0 (or can be set by the administrator based on the vehicle's stopping speed), the reference time is set to the maximum value (in this embodiment, the maximum value is 300 seconds by default, which can be adjusted by the administrator based on the longest underground tunnel length). Finally, a set of reference times for vehicles at each location reaching the intersection is formed, completing the entire calculation process.

[0043] In a pre-defined lane map, the current traffic light signal is broadcast based on the maximum signal transmission strength within a specified range. This maximum signal transmission strength is determined using RSSI signal strength detection technology, combined with historical data on the coverage areas corresponding to different signal transmission strengths, to select the transmission power that completely covers the specified range while maintaining the highest signal strength. Simultaneously, signal strength directional control technology (achieved by adjusting the transmission angle of the communication module) confines the maximum transmission strength signal within the specified range, preventing crosstalk between adjacent intersections caused by the signal exceeding the specified range. This ensures accurate signal coverage, enhances the signal's anti-interference capability within the specified range, and reduces the impact of noise generated by electromechanical equipment within the lane.

[0044] When the distance between the vehicle's location information in the response message and the corresponding intersection is not less than the preset minimum deceleration distance (set by the administrator according to driving safety settings), the vehicle's speed is continuously monitored through the vehicle's unique identifier. Specifically, based on the vehicle's unique identifier, the system continuously receives response or deceleration feedback information from the vehicle (in this embodiment, the default feedback period is set to 1 second, which can be adjusted by the administrator), extracts location information at different time points, calculates the ratio of the location distance difference to the time difference between adjacent time points, and obtains the vehicle's speed during the corresponding time period, thus achieving continuous monitoring of the speed of a single vehicle.

[0045] If the vehicle speed does not decrease, the start time of the next passage period is postponed, and the duration of the next passage period is used as a reference duration. If the vehicle speed decreases within the reference duration, the start time of the next passage period is restored to the time before the postponement; if the vehicle speed still does not decrease, the start time of the next passage period remains unchanged. The reference duration is usually 2-5 seconds, adjusted by the administrator based on the braking performance of the underground vehicles; in this embodiment, 3 seconds is used.

[0046] When postponing the start time of the next traffic period, the deceleration duration is calculated based on the difference between the vehicle's current speed and the preset intersection speed, as well as the preset deceleration acceleration. The start time of the next traffic period is then postponed by the deceleration duration. The deceleration duration is calculated using a formula that combines the speed difference and the preset deceleration acceleration, with standardized unit conversions. The safe passage speed and deceleration acceleration at the intersection are preset parameters by the administrator, and the calculation is completed based on actual vehicle speed examples. The start time of traffic at the intersection is then postponed based on the obtained deceleration duration.

[0047] The corresponding intersection includes traffic light signals in multiple phases, such as four phases: east-west straight, east-west turning, north-south straight, and north-south turning. The passage order of each phase is preset by the administrator and determined based on the priority of the underground traffic flow direction. When the traffic light is in the phase where passage is permitted, a deceleration signal is sent to the vehicles during the deceleration period before the end of the passage time, and the deceleration feedback information from the vehicles in response to the deceleration signal is received. The deceleration feedback information includes vehicle position information.

[0048] The system analyzes the vehicle speed change trend (deceleration or acceleration trend) based on the transmission time of vehicle location information and deceleration feedback information. If the vehicle speed does not decrease (i.e., the vehicle does not decelerate), the start time of the next passage period in other phases of the traffic light signal at the corresponding intersection is postponed. Specifically, two consecutive sets of vehicle speed data are collected, and a preset speed difference is used as a judgment threshold. If the vehicle speed in the later cycle is significantly lower than that in the previous cycle, it is judged as a valid deceleration trend; if the vehicle speed does not decrease, it is directly judged that the vehicle has not decelerated.

[0049] Before adjusting the start time of the next passage period, the speeds of all vehicles within the same road segment are statistically analyzed on the preset tunnel map based on vehicle location information, and the trends in speed changes are analyzed. If the percentage of vehicles exhibiting the same speed trend exceeds a preset same-direction threshold (the same-direction threshold is set by the administrator based on the underground tunnel conditions; for example, 70%-80% for straight sections with high traffic volume during peak hours, and 60%-70% for off-peak hours or sloping sections, ensuring the threshold matches the common speed trends of actual traffic flow and avoiding the impact of a single vehicle's abnormality on overall control), then the start time of the next passage period remains unchanged. Specifically, the speed change trends (deceleration or no deceleration) of all vehicles within the same road segment are statistically analyzed, and the ratio of the number of vehicles exhibiting the same trend to the total number of vehicles is calculated. If this ratio is greater than the preset same-direction threshold, the passage period remains unchanged; if it is less than or equal to the preset same-direction threshold, the passage period is adjusted according to the aforementioned rules.

[0050] In practice, at underground intersections, the geographical coordinates of the pre-set tunnel map are first mapped to the entrances and exits. The administrator then pre-sets various control parameters according to the working conditions. During the traffic light's prohibited phase, a signal containing the permitted time period and lane is broadcast. Vehicles are located and matched to their lane, and respond with information including their identity, lane, and location. The traffic light integrates the response information, broadcast time, and transmission intensity into historical data.

[0051] After cleaning historical data and removing outliers, the map is gridded, and the number of vehicles in each grid is counted according to a fixed time dimension. The driving speed is calculated by combining the spatiotemporal location information of vehicle identification. An algorithm is used to fit the first correlation between speed and quantity. The passage time and restricted passage time in the historical data are extracted and filtered, and the minimum passage time of the corresponding intersection is calculated and the association is completed.

[0052] The system extracts the response information of the current signal, counts the real-time number of vehicles in each grid, calls the first correlation relationship to match the speed, calculates the comparison duration based on the distance between the grid and the intersection, and broadcasts a signal with the maximum transmission intensity within the comparison range after defining the comparison range. When a vehicle reaches the preset minimum deceleration distance from the intersection, it continuously receives feedback information based on its identification and calculates its driving speed to achieve monitoring; if the vehicle speed does not decrease, it calculates the deceleration duration based on the speed difference and the preset deceleration acceleration, postpones the passage period and sets a reference duration, and adjusts the passage time according to the vehicle speed change within the reference duration.

[0053] Before the end of a traffic light phase, a deceleration signal is sent in advance, and the speed trend is analyzed based on the deceleration information fed back by vehicles. If no deceleration is achieved, the passage time of other phases is postponed. Before adjusting the passage time, the speed of vehicles on the same road segment is statistically analyzed, and the proportion of vehicles with the same trend is calculated. If the proportion exceeds the preset same-direction threshold, the passage time remains unchanged to adapt to the overall traffic flow.

[0054] This embodiment also includes an underground intelligent traffic light control system that uses an underground intelligent traffic light control method.

[0055] The system comprises a traffic light terminal, a vehicle terminal (typically an in-vehicle terminal), and an administrator terminal. These three entities establish a communication connection via a LoRa wireless communication module (in this embodiment, the LoRaWAN protocol is used by default) to enable data exchange. The traffic light terminal includes the aforementioned industrial-grade microcontroller, LoRa wireless communication module, SD card storage module, and power management module. It also includes a traffic light display module (in this embodiment, an LED display is used by default, featuring waterproof, dustproof, and strong light resistance, suitable for the harsh underground environment) and a location positioning module (GPS + BeiDou dual-mode positioning is used to determine the traffic light's own position). The vehicle terminal is mounted on the underground transport vehicle and includes a positioning module (of the same model as the traffic light terminal's positioning module), a communication module (compatible with the traffic light terminal's communication module), a speed detection module (in this embodiment, a Hall sensor is used by default to detect vehicle wheel speed and convert it into driving speed), and a feedback module, used to receive traffic light signals and provide response and deceleration feedback information. The administrator terminal uses an industrial-grade tablet or computer and has functions such as data display, parameter setting, map updating, and historical data query. It can communicate bidirectionally with the traffic light terminal to achieve remote adjustment of control parameters and data synchronization. The workflow of this system corresponds one-to-one with the steps of the aforementioned intelligent traffic light control method in the mine, ensuring the feasibility of the method. The connection relationship of each module is as follows: the microcontroller is electrically connected to the LoRa wireless communication module, SD card storage module, power management module, traffic light display module, and location positioning module respectively; the communication module is wirelessly connected to the vehicle terminal and the administrator terminal respectively; the feedback module of the vehicle terminal is electrically connected to the LoRa wireless communication module; and the administrator terminal realizes data interaction with the traffic light terminal through the communication protocol.

[0056] Example 2 The only difference between this embodiment and Embodiment 1 is that, after delaying the start time of the next passage period, if the vehicle speed does not decrease, the system determines whether there is a vehicle ahead based on the vehicle's position information. This embodiment establishes position matching logic based on the one-way traffic rules and lane division attributes of the underground tunnels, using the vehicle's lane number and travel direction coordinate range as basic mapping variables to filter the front and rear positions of vehicles in the same lane. If there is a vehicle ahead, and the distance between the vehicle and the vehicle ahead calculated based on the travel speed is greater than a preset safe braking distance, a lane-changing or deceleration prompt is sent to the vehicle ahead based on the vehicle's position information.

[0057] Specifically, based on the vehicle identification and real-time location information in the response information, the real-time location information includes the tunnel coordinates, the lane, and the direction of travel. The vehicle's direction of travel is determined by the position change trend of multiple sets of positioning coordinates. In the preset tunnel map, the coordinates, lane, and direction of travel of the current vehicle are first located. A data traversal and comparison algorithm for the same lane is used, with lane number, direction of travel, and coordinate order as the filtering criteria, to search for other vehicle response information in the same lane and direction of travel that is in front of the current vehicle (determined by the direction of travel in the tunnel). If there is at least one valid message (for example, data that has exceeded the timeout by more than 3 seconds, the timeout value is uniformly preset by the administrator in combination with the underground communication delay conditions), it is determined that there is a vehicle in front of the current vehicle; if there is no valid message, it is determined that there is no vehicle in front.

[0058] Specifically, the system first locates the positions of vehicles in the same lane and ahead on a pre-defined lane map using the vehicle's identification, lane, real-time coordinates, and direction of travel from the vehicle's response information, then calculates the distance between the two vehicles. The actual distance between the vehicles is then calculated by combining the longitudinal lane position difference between the two vehicles. The system corrects for straight-line coordinate deviations based on the lane's travel route throughout the process, resulting in a precise distance between the two vehicles. When the distance is less than the safe braking distance, a precise warning message is sent to the vehicle ahead: if there are no oncoming vehicles in the adjacent lane and lane changing is possible, a lane change warning (including the target lane indicator) is sent; if lane change conditions are not met, a deceleration warning (including a suggested deceleration amount) is sent.

[0059] In practice, if the vehicle speed does not decrease after the start time of the next traffic period is postponed, the system will determine whether there is a vehicle ahead based on the vehicle's location information. If there is a vehicle ahead, and the distance calculated based on the vehicle speed is greater than the preset safe braking distance, a lane change or deceleration warning will be sent to the vehicle ahead.

[0060] Specifically, by using the vehicle identification, coordinates, lane, and direction of travel in the response information, the system locates the vehicle ahead in the same lane and direction on the preset tunnel map, filters valid data to determine if the vehicle ahead exists, calculates the distance between vehicles, and when the conditions are met, issues lane change or deceleration prompts to the vehicle ahead based on whether the adjacent lanes are empty, guiding the vehicle ahead to cooperate and avoid the obstacle, thus ensuring the safety of underground traffic.

[0061] Example 3 The only difference between this embodiment and embodiments 1-2 is that the traffic light signal also includes intersection entrance information; the intersection entrance information is a binding information composed of a unique number for each intersection, an entrance lane code, and an intersection location identifier, which serves as the basic identification variable for distinguishing different intersections and different entry lanes.

[0062] The pre-defined tunnel map contains a mapping relationship between entrance lanes and corresponding exit lanes at intersections. This mapping relationship uses the entrance lane code as the input variable and the exit lane code as the output variable to establish a one-to-one or one-to-many fixed matching association. For example, a single straight-through entrance lane is fixedly mapped to a straight-through exit lane, and a left-turn entrance lane is fixedly mapped to a left-turn exit lane. All mapping combinations are pre-stored in the traffic light's local storage module in the form of a data table. This data is pre-entered by administrators according to the underground tunnel road network plan and can be updated periodically.

[0063] When the traffic light is in a "passing" state, vehicles passing through the corresponding intersection are designated as relay vehicles, and the exit lane corresponding to the relay vehicle's path is designated as the relay lane. The relay vehicle uses the traffic light signal corresponding to the relay lane as the relay signal. When the received signal strength is greater than the preset near-distance strength (the administrator uses the signal coverage distance of the traffic light at the intersection entrance as the basis for setting the signal strength value corresponding to the edge of the effective coverage area of ​​the intersection, ensuring that only vehicles entering the near-distance area of ​​the intersection can receive and act as relays, avoiding false triggering at long distances), the relay signal is received and stored. The vehicle terminal is equipped with a local cache storage unit to temporarily cache the complete relay signal data, ensuring data integrity during signal forwarding. After the relay vehicle enters the relay lane, it broadcasts the relay signal before the start time of the next passing time period corresponding to the relay signal. The relay signal uses a directional broadcast mode, limiting the broadcast range to the upstream lane area of ​​the relay lane to avoid the spread of invalid signals.

[0064] The traffic light signal includes the communication address of the traffic light. The communication address is a unique communication identification code for each traffic light. After receiving the relay signal, the relay vehicle sends a carrying signal to the traffic light according to the communication address (a signal informing the traffic light that it will assist in propagation; in this embodiment, the carrying signal is a short message feedback signal, used to unilaterally inform the corresponding traffic light that the current vehicle has successfully acquired and temporarily stored the relay signal and is about to execute the signal relay forwarding action); at the start time of the next passage time corresponding to the relay signal, the relay vehicle sends a carrying end signal to the traffic light according to the communication address (a signal informing the traffic light that it will no longer assist in propagation). The carrying end signal is a relay task termination feedback signal, used to indicate that the vehicle signal broadcasting process is complete and the relay function is deactivated.

[0065] After receiving the relay signal, the vehicle sends a response message to the traffic light based on the communication address. Upon receiving the relay signal, the traffic light stops broadcasting traffic light signals until it receives a signal indicating the end of relaying or a response message. This establishes a timing switching logic between the traffic light's native broadcast and the vehicle's relay broadcast. The two broadcast modes operate mutually exclusively to avoid electromagnetic interference caused by the superposition of dual signals.

[0066] In practice, traffic light signals are augmented with intersection entrance information, and a pre-defined lane map stores the mapping relationship between entrance and exit lanes. When the traffic light is in operation, vehicles passing through the intersection are treated as relay vehicles, and their corresponding exit lanes are designated as relay lanes. When a relay vehicle receives a signal strength greater than a preset near-range strength, it receives and stores the corresponding relay signal; upon entering the relay lane, it broadcasts the relay signal before the start of the next traffic period. Relay vehicles send a carrying signal and a carrying-to-end signal to the traffic light according to their communication addresses, and other vehicles respond with a reply according to their communication addresses after receiving the relay signal. The traffic light stops broadcasting upon receiving the carrying signal until it receives the carrying-to-end signal or a reply, thereby improving signal coverage and transmission reliability at underground intersections.

[0067] Example 4 The only difference between this embodiment and embodiments 1-3 is that the traffic light statistically analyzes the reception frequency of the carried signal and response information received at different times. Based on the differences in the distribution of the carried signal reception frequency and the response information reception frequency over time, the start time of the next passage period for the traffic light corresponding to the relay signal is adjusted. The carried signal reception frequency is defined as the total number of times the traffic light receives carried signals from relay vehicles per unit time, and the response information reception frequency is defined as the total number of times the traffic light receives response information from various types of vehicles per unit time.

[0068] Simultaneously, the signal transmission frequency and intensity of the broadcast relay signal are adjusted according to the signal reception frequency. This forms a closed-loop control logic between frequency monitoring, difference analysis, and precise control, enabling dynamic adaptation of passage timing and signal transmission parameters.

[0069] The traffic light establishes timestamped reception logs for both signal-carrying and response information, accurately recording the reception time, corresponding communication address, and signal type for each message. The reception logs are stored in a structured data format, with each record containing a unique log number, a reception timestamp (accurate to the second in this embodiment), a communication address code, and a signal type identifier (0 indicates signal-carrying information, and 1 indicates response information in this embodiment). These logs are stored in the traffic light's local storage module and can be retrieved by time interval and signal type. The administrator presets the statistical time granularity (e.g., 1 minute or 5 minutes) based on the underground traffic flow fluctuations, while also pre-setting the statistical period to be consistent with the statistical time granularity. The logs are then iterated according to this granularity, counting the total number of receptions of both types of signals within each time interval. The reception frequency per unit time is calculated by "number of receptions ÷ time granularity duration," generating a time-series frequency data table for signal-carrying and response information, providing basic data support for subsequent difference analysis.

[0070] Traffic lights call the timing frequency data table to draw the frequency and time distribution curves of the two types of signals. First, they extract the timing characteristics such as the peak time and high-frequency period carrying the signal and response information. Then, they calculate the peak time difference and high-frequency overlap. By weighting, they obtain the comprehensive deviation coefficient, which determines whether the two types of signals are ahead, behind, or matched in time, providing a basis for subsequent adjustments. First, the peak times and high- and low-frequency periods of the two types of signals are extracted. Then, the peak time difference, high-frequency overlap duration, and low-frequency duration are calculated. The focus is on identifying differences in peak time offset (e.g., the peak of the signal is at 9:00, and the peak of the response information is at 9:05), high-frequency overlap (e.g., both types of signals are at high frequency between 14:00 and 15:00, with an overlap of 80%), and low-frequency duration. A deviation coefficient is used to quantify the time distribution difference (deviation coefficient = |peak time difference between the two types of signals| ÷ statistical period). The statistical period is completely consistent with the preset statistical time granularity. In this embodiment, the deviation coefficient ranges from 0 to 1. The larger the value, the greater the time distribution difference between the two types of signals. The ±0.1 threshold of the deviation coefficient is set based on the average response time of the underground vehicle, combined with the relay signal transmission delay and the vehicle braking reaction time, to ensure that the threshold setting fits the actual working conditions, clarify the core dimensions and numerical range of the difference, and provide a quantitative basis for control.

[0071] If the response information lags behind the carried signal during high-frequency periods (e.g., deviation coefficient > 0.1), it indicates a delay in vehicle response, and the start time of passage corresponding to the relay signal needs to be delayed. The delay duration = deviation coefficient × statistical period. If the response information is earlier during high-frequency periods (e.g., deviation coefficient < -0.1), it indicates that vehicles are gathering earlier, and the start time needs to be advanced. The advance duration is calculated using the same logic. If the deviation coefficient is within ±0.1, it indicates that the time distribution is matched. The start time should be kept unchanged to ensure that the passage period is synchronized with the vehicle response rhythm.

[0072] Set the frequency threshold range for the carried signal (preset by the administrator based on the underground traffic density). When the received frequency of the carried signal is higher than the upper threshold, it indicates that there are too many relay vehicles and signal redundancy. The transmission frequency needs to be reduced (e.g., from 10 times / minute to 6 times / minute), and the transmission intensity needs to be reduced (e.g., from 80% to 60%) to avoid signal interference. When the frequency is lower than the lower threshold, it indicates that the relay coverage is insufficient. The transmission frequency needs to be increased (e.g., from 6 times / minute to 10 times / minute), the transmission intensity needs to be increased (e.g., increased to 120% of the original intensity), and the signal coverage area needs to be expanded (e.g., the effective signal coverage distance is extended by 50 meters) to ensure stable reception by vehicles.

[0073] In practice, the traffic lights statistically analyze the reception frequencies of the signals and responses received at different times. Based on the differences in the distribution of the reception frequencies of the two types of signals in the time dimension, the start time of the next passage period for the relay signal corresponding to the traffic light is adjusted. At the same time, the transmission frequency and transmission strength of the broadcast relay signal are adjusted according to the reception frequency of the signals.

[0074] Traffic lights establish timestamped reception logs for both signal and response information, recording the reception time, communication address, and signal type. Administrators preset the statistical time granularity, count the total number of received messages by time interval, calculate the reception frequency per unit time, and generate a time-series frequency data table.

[0075] Traffic lights extract features such as peak time, high-frequency period, and low-frequency period based on time-series frequency data, calculate peak time difference, high-frequency overlap and low-frequency duration, and use deviation coefficient to quantify time distribution differences to determine signal timing matching relationship.

[0076] If the response information lags behind the carried signal during high-frequency periods, the passage start time is delayed; if the response information is earlier during high-frequency periods, the passage start time is advanced; if the deviation is within a reasonable range, the time remains unchanged.

[0077] Traffic lights determine relay status based on preset frequency threshold ranges: when the receiving frequency of the signal is too high, the transmission frequency and transmission strength are reduced to reduce signal interference; when the receiving frequency is too low, the transmission frequency and transmission strength are increased to enhance signal coverage and ensure reliable reception and orderly passage of underground vehicles.

[0078] The above are merely embodiments of the present invention. The invention is not limited to the fields covered by these embodiments. Commonly known structures and characteristics in the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are able to access all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for controlling intelligent traffic lights in underground mines, characterized in that, Includes the following steps: When the traffic light is in the prohibited phase at the intersection, a traffic light signal containing the next permitted time period is broadcast into the alleyway. At the same time, response information from vehicles is received. The response information includes the vehicle's identification and the vehicle's location information when it received the traffic light signal. The response information, the broadcast time of the corresponding traffic light signal, and the signal transmission strength are used as historical data. Based on the signal transmission strength and vehicle location information in historical data, the coverage area corresponding to different signal transmission strengths is marked in the preset lane map; the number distribution of vehicles at different times in the preset lane map is statistically analyzed from historical data; at the same time, the driving speed of vehicles at different locations in the preset lane map is obtained based on the vehicle location information and vehicle identification in the response information; the driving speed and the number distribution are correlated to obtain the first correlation relationship. Based on the vehicle identification in historical data, the time from when a vehicle receives a traffic light signal to when it arrives at the corresponding intersection is obtained as the passage time. At the same time, the time interval between when the vehicle passes through the intersection and the start of the next passage time period is obtained as the prohibition time. Statistical analysis is performed to determine the minimum transit time when the restricted driving time is no greater than the preset minimum restricted driving time, and the minimum transit time is then associated with the corresponding intersection. Obtain the response information corresponding to the currently broadcast traffic light signal, count the number distribution of vehicles at each location on the preset lane map, obtain the vehicle speed at each location by combining the first correlation, obtain the time taken for vehicles at each location to travel to the corresponding intersection by combining the distance between each location and the intersection corresponding to the traffic light, and use the comparison time as the comparison range; use the coverage area formed by the location of the vehicles corresponding to the comparison time on the preset lane map as the comparison range. The current traffic light signal is broadcast in the preset lane map with the maximum signal transmission intensity within the reference range.

2. The method for controlling intelligent traffic lights in underground mines according to claim 1, characterized in that: When the distance between the vehicle location information in the response message and the corresponding intersection is not less than the preset minimum deceleration distance, the vehicle speed is continuously monitored through the vehicle identification mark. If the vehicle speed does not decrease, the start time of the next passage period will be postponed, and the change in the duration of the next passage period will be used as a reference duration; if the vehicle speed decreases within the reference duration, the start time of the next passage period will be restored to the time before the postponement. If the vehicle speed does not decrease, the start time of the next passage period will remain unchanged. When the start time of the next passage period is postponed, the deceleration time is calculated based on the difference between the vehicle's current speed and the preset intersection speed, as well as the preset deceleration acceleration. The start time of the next passage period is then postponed by the deceleration time.

3. The method for controlling intelligent traffic lights in underground mines according to claim 1, characterized in that: The corresponding intersection includes traffic light signals with multiple phases. When the traffic light is in the phase where passage is permitted at the intersection, a deceleration signal is sent to the vehicle during the deceleration period before the end of the passage time, and deceleration feedback information from the vehicle in response to the deceleration signal is received. The deceleration feedback information includes vehicle position information. Analyze the vehicle speed change trend based on the transmission time of vehicle location information and deceleration feedback information. If the vehicle speed does not decrease, postpone the start time of the next passage period in other phases of traffic light signals at the corresponding intersection.

4. The intelligent traffic light control method for underground mines according to claim 1, characterized in that: Before adjusting the start time of the next passage period, the driving speed of all vehicles in the same road segment is counted in the preset lane map based on the vehicle location information, and the trend of the driving speed of all vehicles is analyzed. If the proportion of vehicles with the same driving speed trend exceeds the preset same-direction threshold, the start time of the next passage period remains unchanged.

5. A method for controlling intelligent traffic lights in underground mines according to claim 2 or 3, characterized in that: If the vehicle speed does not decrease after the start time of the next passage period is postponed, the vehicle location information will be used to determine whether there is a vehicle in front of the vehicle. If there is a vehicle ahead, and the distance between the vehicle and the vehicle ahead calculated based on the driving speed is greater than the preset safe braking distance, then a lane change or deceleration prompt message will be sent to the vehicle ahead based on the vehicle's position information.

6. The method for controlling intelligent traffic lights in underground mines according to claim 1, characterized in that: Traffic light signals also include intersection entrance information; the preset lane map stores the mapping relationship between intersection entrance lanes and corresponding intersection exit lanes; When the traffic light is in the "passing" state, vehicles passing through the corresponding intersection are designated as relay vehicles, and the exit lane corresponding to the relay vehicle's travel path is designated as the relay lane. The relay vehicle uses the traffic light signal corresponding to the relay lane as the relay signal. When the received strength of the relay signal is greater than the preset short-range strength, it receives and stores the relay signal. After a relay vehicle enters the relay lane, it broadcasts the relay signal before the start time of the next passage period corresponding to the relay signal.

7. The method for controlling intelligent traffic lights in underground mines according to claim 6, characterized in that: The traffic light signal contains the communication address of the traffic light; After receiving the relay signal, the relay vehicle sends a signal to the traffic light according to the communication address; at the start time of the next passage time corresponding to the relay signal, the relay vehicle sends a signal to the traffic light according to the communication address to end the signal. After receiving the relay signal, the vehicle sends a response message to the traffic light according to the communication address.

8. The method for controlling intelligent traffic lights in underground mines according to claim 7, characterized in that: After receiving the signal carried by the traffic light, the traffic light stops broadcasting the traffic light signal until it receives the signal indicating the end of the signal carrying or a response message.

9. The intelligent traffic light control method for underground mines according to claim 7, characterized in that: Traffic lights statistically analyze the reception frequency of the signal and response information received at different times, and adjust the start time of the next passage period of the traffic light corresponding to the relay signal based on the difference in the distribution of the signal reception frequency and the response information reception frequency in the time dimension. At the same time, the signal transmission frequency and signal transmission strength of the broadcast relay signal are adjusted according to the signal receiving frequency.

10. An intelligent traffic light control system for underground mines, characterized in that, The method for controlling intelligent traffic lights in underground mines as described in any one of claims 1-9 is used.

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