A low-carbon energy-saving control system and method for street lamps based on vehicle trajectory prediction

Abstract

The application discloses a kind of low-carbon energy-saving control system and method of street lamp based on vehicle trajectory prediction, it is related to road lighting control technical field.The method obtains the continuous position and motion state of road target, generates candidate trajectory in combination with road topology, determines trajectory separation point, associated street lamp group and credibility;According to candidate trajectory and target predicted arrival time, determine positioning observation period and dimming execution limit, generate candidate lighting task with trajectory identification for each candidate trajectory, and issue to street lamp controller in advance before positioning observation period;In response to the overlap of positioning observation period and dimming message transmission period, limit the sending and relay forwarding of non-emergency dimming message, confirm target trajectory using positioning observation data and send corresponding trajectory identification, so that street lamp controller calls candidate lighting task to carry out continuous dimming.The application can reduce the influence of dimming communication on positioning observation, avoid candidate branch repeated brightening, and reduce invalid lighting energy consumption.

Description

Technical Field

[0001] This invention relates to the field of road lighting control technology, specifically to a low-carbon and energy-saving control system and method for streetlights based on pedestrian and vehicle trajectory prediction. Background Technology

[0002] As urban road lighting systems develop towards intelligence and low carbon emissions, on-demand dimming of streetlights based on pedestrian and vehicle sensing data has become an important way to reduce road lighting energy consumption. Existing smart streetlight control systems typically use Bluetooth positioning devices, microwave sensors, or infrared sensors to obtain the position, direction of movement, and speed of pedestrians and vehicles. Based on continuous sensing results, they predict the subsequent movement trajectories of pedestrians and vehicles, and use a wireless mesh network to pre-brighten streetlights ahead of the predicted trajectory while reducing the brightness of streetlights in areas where pedestrians and vehicles leave, thereby reducing lighting energy consumption when there is no target.

[0003] However, in lighting control systems that rely on streetlight nodes for road target perception and network dimming, the reception of target positioning signals and the transmission and relay of dimming messages typically require shared wireless communication resources. During the approach phase of road branches, the system needs to continuously acquire positioning observation data with branch identification capabilities while simultaneously controlling the dimming of associated streetlights before the target arrives. This easily leads to overlap between the positioning observation period and the dimming message transmission period. In particular, when the target trajectory is not yet confirmed, the more candidate branches there are, the more dimming messages need to be sent or relayed. The continuous occupation of wireless resources by dimming communication reduces the continuity of positioning observation, further delaying the confirmation of the target trajectory. This creates a technical contradiction where trajectory uncertainty and dimming communication occupation mutually exacerbate each other. Existing technologies mostly focus on improving trajectory prediction accuracy or adjusting streetlight brightness in advance based on prediction results, but they are still insufficient to suppress the reverse interference of dimming communication on the critical positioning observation process while ensuring the timeliness and safety of road lighting. Summary of the Invention

[0004] The purpose of this invention is to provide a low-carbon and energy-saving control system and method for streetlights based on human and vehicle trajectory prediction, so as to solve the problems mentioned in the background art.

[0005] To address the aforementioned technical problems, this invention provides the following technical solution: a low-carbon and energy-saving control method for streetlights based on pedestrian and vehicle trajectory prediction, comprising: S1. Obtain the continuous position and motion state of the road target, generate candidate trajectories by combining the road topology, and determine the trajectory separation point, associated street light group and confidence level of each candidate trajectory. S2. Determine the location observation period to be protected based on the credibility of the candidate trajectory and the estimated time of the target's arrival at the trajectory separation point; determine the dimming execution period based on the predicted time of the target's arrival at each associated street light lighting area. S3. Generate candidate lighting tasks with trajectory identifiers for each candidate trajectory. The candidate lighting tasks include the brightness change order and activation conditions of the associated streetlights. Before the start of the positioning observation period, the candidate lighting tasks are pre-issued to the corresponding streetlight controllers according to the dimming execution period. S4. In response to the overlap between the positioning observation period and the dimming message transmission period in the shared wireless communication resources, restrict the transmission and relay forwarding of non-urgent dimming messages during the positioning observation period, and update the candidate trajectory using the obtained positioning observation data. S5. In response to the confirmation of the target trajectory, send the trajectory identifier corresponding to the target trajectory, so that the street light controller can call the issued candidate lighting tasks for continuous dimming; in response to the failure to confirm the target trajectory, make the street lights in the road sections that the candidate trajectories pass through brighter, and make the street lights in the branch road sections maintain a safe brightness.

[0006] According to the above technical solution, the step of generating candidate trajectories by combining road topology includes: Road intersections, road entrances / exits, and road turning points are used as road connection nodes, and the roads between adjacent road connection nodes are used as directed road segments. A mapping relationship between each directed road segment and the street lighting area is established. Based on the target's current position, moving speed, and preset maximum acceleration and maximum deceleration, determine the target's reachable distance range in the predicted time domain; From the directed road segments that are connected to the current directed road segment of the target and intersect with the reachable distance range, the directed road segments that do not meet the road travel direction are eliminated to form candidate trajectories; The credibility of candidate trajectories is determined based on the lateral offset of the target relative to the candidate road entrance, the angle between the target's movement direction and the candidate road extension direction, and the continuity of the target's movement speed. The road connection nodes that correspond to different oriented road segments for the first time for different candidate trajectories are identified as trajectory separation points.

[0007] Based on the above technical solution, the positioning and observation period to be protected is determined, including: Based on the sensing nodes passed by each candidate trajectory and the predicted distance between the target and each sensing node, a expected observation feature sequence corresponding to each candidate trajectory is generated. The expected observation feature sequence includes sensing node identifiers, Bluetooth received signal strength range, and target passing order. Compare the expected observation feature sequences of different candidate trajectories, and determine the position where the feature difference between at least two expected observation feature sequences first reaches a preset identifiable threshold as the trajectory identification position; Based on the estimated time of the target's arrival at the trajectory identification location, the number of effective positioning samples required to complete one trajectory identification, and the historical missing proportion of positioning samples, the start time and duration of the positioning observation period are determined so that the positioning observation period covers the positioning sampling process before and after the target arrives at the trajectory identification location.

[0008] According to the above technical solution, the dimming execution period is the difference between the predicted time when the target enters the corresponding street light illumination area and the time it takes for the street light brightness to establish; The estimated transmission time of the candidate lighting task is determined based on the data volume of the candidate lighting task, the number of relay hops between the street light controller and the gateway, the single-hop message transmission time, the number of historical retransmissions, and the current message queue length. In response to the overlap between the dimming message transmission period formed according to the expected transmission duration and the positioning observation period, candidate lighting tasks are transmitted before the start of the positioning observation period in the order of dimming execution deadline from earliest to latest. For road segments traversed by different candidate trajectories, a common lighting task is issued only once, and the corresponding branch road segments' differential dimming data relative to the common lighting task are issued in each candidate lighting task.

[0009] According to the above technical solution, during the positioning and observation period, the street light nodes suspend the generation of new non-emergency dimming messages and temporarily suspend the relay forwarding of non-emergency dimming messages that have entered the message queue, while retaining the transmission rights of minimum safe lighting messages and fault alarm messages. Record the transmit and receive status of the wireless communication unit when each sensing node collects positioning observation data, and remove positioning observation data in which the wireless communication unit is in the dimming message sending state or relay forwarding state during the collection period; The Bluetooth received signal strength data, microwave velocity measurement data, and infrared target presence data with a time difference not exceeding the preset synchronization time difference are combined into an observation data group. When the number of effective observation data groups is lower than the number required for trajectory identification, the positioning observation period is extended until the preset maximum protection time is reached.

[0010] According to the above technical solution, candidate trajectories are updated using positioning observation data, including: The actual observation feature sequences obtained during the positioning observation period are time-aligned with the expected observation feature sequences of each candidate trajectory. The observation matching degree of each candidate trajectory is determined based on the deviation of Bluetooth received signal strength, the deviation of the passing order of sensing nodes, the deviation of microwave velocity measurement, and the consistency of the infrared target's existence status. When the same candidate trajectory has the highest observation matching degree in multiple consecutive observation data sets, and the difference between it and the second highest observation matching degree reaches the trajectory confirmation threshold, the candidate trajectory is determined as the target trajectory. When the candidate trajectory corresponding to the highest observation matching degree switches multiple times within a preset time period, the lighting task of the common road segment is maintained, the target brightness of any branch road segment is not activated, and the number of effective positioning samples required for the next positioning observation period is increased.

[0011] According to the above technical solution, the candidate lighting task also includes trajectory identifier, street light node address, predicted arrival time, initial brightness, safe brightness, target brightness, brightness change rate, brightness maintenance duration, and task failure time; After receiving candidate lighting tasks, the street light controller stores the candidate lighting tasks in the local task area and corrects the predicted arrival time based on the synchronization deviation between the local clock and the gateway clock. In response to receiving the trajectory identifier, the street light controller calls up the candidate lighting task with the same trajectory identifier from the local task area, and controls the street light to brighten sequentially according to the corrected predicted arrival time and brightness change rate. In response to the failure to receive a trajectory identifier before the task expires, the street light controller executes a safety lighting task and deletes branch lighting tasks that do not meet the activation conditions.

[0012] According to the above technical solution, when there are multiple targets in the road area, the candidate lighting tasks of each target are converted into lighting demand time intervals corresponding to each street light node. The overlapping lighting demand time intervals on the same street light node are merged into a joint lighting interval, and the highest target brightness corresponding to different targets within the joint lighting interval is used as the execution brightness of the street light node. The earliest predicted arrival time is used as the basis for increasing brightness, and the latest predicted departure time is used as the basis for decreasing brightness. When the time interval between adjacent combined lighting zones is less than the time required for a street light to decrease from a safe brightness to a base brightness and then recover to a safe brightness, the adjacent combined lighting zones shall be merged. Difference update messages are generated only when the start and end times of the combined lighting zone, the execution brightness, or the associated trajectory identifier changes, and the street light controller uses the difference update messages to modify the stored candidate lighting tasks.

[0013] The present invention also provides a low-carbon and energy-saving control system for streetlights based on human and vehicle trajectory prediction, including a human and vehicle perception module, a trajectory prediction module, an observation period determination module, a candidate task generation module, a communication coordination module, and a streetlight controller; The human and vehicle perception module is used to acquire the continuous position and motion state of road targets; The trajectory prediction module is used to generate candidate trajectories by combining road topology, and to determine trajectory break-off points, associated street light groups, and confidence levels. The observation period determination module is used to determine the location observation period to be protected and the dimming execution period of each associated street light; The candidate task generation module is used to generate candidate lighting tasks with trajectory identifiers for each candidate trajectory, and to pre-send the candidate lighting tasks to the street light controller before the start of the positioning observation period. The communication coordination module is used to respond to the overlap between the positioning observation period and the dimming message transmission period, restrict the sending and relaying of non-emergency dimming messages during the positioning observation period, and send the corresponding trajectory identifier after the target trajectory is confirmed. The street light controller is used to store candidate lighting tasks and, in response to receiving a trajectory identifier, calls the corresponding candidate lighting task for continuous dimming.

[0014] According to the above technical solution, the human and vehicle perception module includes a Bluetooth positioning unit, a microwave sensing unit, and an infrared sensing unit. The Bluetooth positioning unit transmits positioning and perception messages with the street light node through a Bluetooth Mesh network. The microwave sensing unit is used to obtain the distance and movement speed of the target. The infrared sensing unit is used to confirm whether the target has entered the street light illumination area. The street light controller includes a wireless communication unit, a local clock, a candidate task storage area, and a dimming interface. The wireless communication unit is used to receive candidate lighting tasks and trajectory identifiers. The candidate task storage area is used to store candidate lighting tasks according to the trajectory identifiers. The dimming interface is used to convert candidate lighting tasks into dimming signals that can be executed by the street light driver. In response to a wireless communication interruption, the street light controller continues to execute the active candidate lighting tasks and restores the street lights to the preset safe brightness after the candidate lighting tasks reach the task failure time.

[0015] Compared with existing technologies, the beneficial effects achieved by this invention are as follows: This invention determines the positioning observation period and dimming execution period based on the candidate trajectory and the expected arrival time of the target, and pre-issues candidate lighting tasks to the corresponding street light controllers before the start of the positioning observation period, so that the configuration process of tasks with large data volumes avoids the positioning observation period that requires key protection; in response to the overlap between the positioning observation period and the dimming message transmission period in the shared wireless communication resources, the sending and relaying of non-emergency dimming messages are restricted during the positioning observation period, so that the positioning observation in the critical branch stage maintains the necessary continuity and identifiability, and avoids the dimming communication occupying further delays in the confirmation of the target trajectory; after the target trajectory is confirmed, only the trajectory identifier corresponding to the candidate lighting task is sent, and the street light controller calls the already issued candidate lighting tasks for continuous dimming, thereby reducing the amount of control message transmission after trajectory confirmation, and preventing the lighting tasks corresponding to unconfirmed candidate trajectories from being called, reducing the energy consumption of ineffective brightening of candidate branches, and achieving a balance between road safety lighting and low-carbon energy-saving control of street lights. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a flowchart illustrating the low-carbon and energy-saving control method for streetlights based on human and vehicle trajectory prediction according to the present invention. Figure 2 This is a schematic diagram of the structure of the low-carbon and energy-saving control system for streetlights based on human and vehicle trajectory prediction of the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1 Please see Figure 1 This embodiment provides a low-carbon and energy-saving control method for streetlights based on pedestrian and vehicle trajectory prediction, including the following steps: S1. Obtain the continuous position and motion state of the road target, generate candidate trajectories by combining the road topology, and determine the trajectory separation point, associated street light group and confidence level of each candidate trajectory.

[0019] The road targets include pedestrians, non-motorized vehicles, and motorized vehicles. The motion state includes at least the direction of movement and the speed of movement, and may also include acceleration, stationary state, and lateral movement trend. Continuous position and motion state can be obtained through at least two of Bluetooth positioning units, microwave sensing units, and infrared sensing units.

[0020] This embodiment uses road intersections, road entrances / exits, and road turning points as road connection nodes, and the roads between adjacent road connection nodes as directed road segments, establishing a mapping relationship between each directed road segment and the streetlight illumination area. The mapping relationship records the installation location, illumination coverage area, road segment to which each streetlight belongs, and its connection order with adjacent streetlights.

[0021] Based on the target's current position, moving speed, and preset maximum acceleration and deceleration, the reachable distance range of the target in the prediction time domain is determined; from the directed road segments connected to the target's current directed road segment and intersecting with the reachable distance range, directed road segments that do not meet the road travel direction are eliminated to form candidate trajectories.

[0022] The credibility of candidate trajectories is determined based on the lateral offset of the target relative to the candidate road entrance, the angle between the target's movement direction and the candidate road extension direction, and the continuity of the target's movement speed. The road connection nodes that correspond to different oriented road segments for the first time for different candidate trajectories are identified as trajectory separation points.

[0023] Specifically, the state deviation of the j-th candidate trajectory can be expressed as: The confidence level of the j-th candidate trajectory is: In the formula, For the target relative to the first Normalized lateral offset of candidate road entrances; For the target movement direction and the first The normalized angle between the extension directions of the candidate roads; Target current speed and entering the first The normalized variation in the required speeds for the candidate roads; , and For the corresponding weights; This represents the number of candidate trajectories.

[0024] Specifically, each state variable is normalized and calculated according to the following formula: in, From the current position of the target to the number The lateral distance between the centerlines of the candidate road entrances. For the first Half the width of the entrance to each candidate road; For the target movement direction and the first The angle between the extension directions of the candidate roads. The preset maximum directional deviation angle is set to 90°. The target current speed and the entry into the th The absolute difference between the required speeds of the candidate roads. This is the maximum permissible velocity change determined based on the target type, preset maximum acceleration, preset maximum deceleration, and prediction time interval. The above normalization calculation is used to... , and All are within the range of 0 to 1.

[0025] Weight , and All are non-negative numbers and satisfy: In engineering applications, The typical value range is 0.25 to 0.40. The typical value range is 0.35 to 0.50. The typical value range is 0.15 to 0.30. In this embodiment, The more pronounced the directional difference between road branch entrances, the greater the risk of [damage / increase]. When road entrances are parallel and have significant differences in lateral distance, increase... When the change in the target's moving speed clearly reflects its turning intention, increase... .

[0026] The design logic of this formula is that the closer the target is to the entrance of a candidate road, the more its movement direction is towards that candidate road, and the more continuous its speed change, the higher the credibility of that candidate trajectory. Credibility is used to characterize the relative probability of the target choosing the corresponding candidate trajectory under the current observation conditions, rather than being used directly as the basis for lighting up all candidate streetlights.

[0027] S2. Determine the location observation period to be protected based on the credibility of the candidate trajectory and the estimated time of the target's arrival at the trajectory separation point, and determine the dimming execution period based on the predicted time of the target's arrival at each associated street lighting area.

[0028] In this embodiment, based on the sensing nodes passed by each candidate trajectory and the predicted distance between the target and each sensing node, a expected observation feature sequence corresponding to each candidate trajectory is generated. The expected observation feature sequence includes sensing node identifiers, Bluetooth received signal strength range, and target passing order.

[0029] By comparing the expected observation feature sequences of different candidate trajectories, the position where the feature difference between at least two expected observation feature sequences first reaches a preset identifiable threshold is determined as the trajectory identification position. For example, if two candidate trajectories correspond to the same sensing node before entering an intersection, but approach sensing nodes on different roads after passing the intersection, the position where the difference in the received signal strength of the different sensing nodes reaches the identifiable threshold is taken as the trajectory identification position.

[0030] Based on the estimated time of the target's arrival at the trajectory identification location, the number of effective positioning samples required to complete one trajectory identification, and the historical missing proportion of positioning samples, the start time and duration of the positioning observation period are determined so that the positioning observation period covers the positioning sampling process before and after the target arrives at the trajectory identification location.

[0031] In this embodiment, the expected observation feature differences corresponding to different candidate trajectories are first normalized to the range of 0 to 1, and the preset identifiable threshold is set to 0.30. When judging whether a candidate trajectory is identifiable using only the range of Bluetooth received signal strength, the preset identifiable threshold corresponds to an effective difference of not less than 8dB between the expected Bluetooth received signal strength ranges of different candidate trajectories; when judging by combining the perception node identifier and the target's passing order, as long as there is a difference in the perception node identifier, or the comprehensive feature difference formed by the passing order difference and the normalized received signal strength difference reaches 0.30, it is determined that the target has reached the trajectory identification position.

[0032] The number of valid observation data sets required to complete one trajectory identification is set to 5 sets, and the positioning sampling frequency is set to 10Hz, ensuring that the basic positioning sampling duration is no less than 0.5s. When the historical missing proportion of positioning samples... When the percentage is not less than 20%, the number of planned observation data sets shall be determined according to the following formula: in, The number of basic valid observation data sets required to complete one trajectory identification is set to 5; This indicates rounding up. By increasing the planned sampling quantity based on the historical missing percentage, it ensures that a specified number of valid observation data sets can still be obtained even when some location samples are missing.

[0033] When the confidence difference between candidate trajectories is small, it indicates that the current motion state is insufficient to confirm the target direction, so the duration of the positioning observation period should be increased; when the estimated time for the target to reach the trajectory identification position is shortened, the start time of the positioning observation period should be advanced; when the proportion of missing historical data increases, the number of planned positioning samples should be increased to avoid trajectory misjudgment caused by the absence of a small number of positioning samples.

[0034] The dimming execution period is the difference between the predicted time when the target enters the corresponding streetlight illumination area and the streetlight brightness establishment time. The streetlight brightness establishment time includes the response time of the streetlight driver after receiving the dimming signal and the gradual change time required for the streetlight to adjust from the current brightness to the target brightness.

[0035] The estimated transmission time of a candidate lighting task is determined based on the data volume of the candidate lighting task, the number of relay hops between the street light controller and the gateway, the single-hop message transmission time, the historical retransmission count, and the current message queue length. The estimated transmission time of the i-th candidate lighting task can be expressed as: In the formula, R represents the data volume of the candidate lighting task; R is the effective transmission rate of the wireless communication resources. This represents the number of relay hops from the gateway to the corresponding street light controller; This refers to the processing time for a single-hop transmission. The estimated number of retransmissions is determined based on historical communication data. This refers to the time taken for a single retransmission; This represents the number of messages in the transmission queue that precede this candidate lighting task. This represents the average queue time for a single prior message.

[0036] This formula converts the time consumption caused by message transmission, relay forwarding, historical retransmission, and current queuing into the communication time occupied by the candidate lighting task, in order to determine whether the candidate lighting task will intrude into the positioning observation period that needs to be protected.

[0037] S3. Generate candidate lighting tasks with trajectory identifiers for each candidate trajectory. The candidate lighting tasks include the brightness change order and activation conditions of the associated streetlights. Before the start of the positioning observation period, the candidate lighting tasks are pre-issued to the corresponding streetlight controllers according to the dimming execution period.

[0038] The candidate lighting task also includes a trajectory identifier, street light node address, predicted arrival time, initial brightness, safe brightness, target brightness, brightness change rate, brightness maintenance duration, and task failure time. The trajectory identifier is used to enable the street light controller to call the candidate lighting task corresponding to the confirmed trajectory from among multiple stored tasks.

[0039] In response to the overlap between the dimming message transmission period (based on the expected transmission duration) and the location observation period, candidate lighting tasks are transmitted before the start of the location observation period, in order of dimming execution deadline from earliest to latest. This converts multiple dimming control messages that would normally be sent collectively after trajectory confirmation into tasks that can be locally invoked by the streetlight controller.

[0040] For road segments traversed by different candidate trajectories, a common lighting task is issued only once, and differential dimming data for the corresponding branch road segments relative to the common lighting task is issued in each candidate lighting task. Using a common lighting task and differential dimming data can avoid repeatedly writing the street light brightness parameters common to all candidate trajectories into multiple candidate lighting tasks.

[0041] After receiving a candidate lighting task, the street light controller stores it in its local task area and corrects the predicted arrival time based on the synchronization deviation between the local clock and the gateway clock. Once pre-issued, the candidate lighting task is in a pending state; the street light controller will not adjust the corresponding branch streetlights to the target brightness simply because it receives a candidate lighting task.

[0042] S4. In response to the overlap between the positioning observation period and the dimming message transmission period in the shared wireless communication resources, restrict the transmission and relay forwarding of non-emergency dimming messages during the positioning observation period, and update the candidate trajectory using the obtained positioning observation data.

[0043] In this embodiment, the acquisition of Bluetooth positioning data, the uploading of sensing results, and the transmission of street light dimming messages share Bluetooth Mesh communication resources. The wireless communication unit of the street light node needs to switch between Bluetooth scanning, message sending, and message relay states. When the street light node continuously sends or relays dimming messages, its effective scanning time for receiving target signals is reduced, which can easily lead to missing received signal strength samples or misalignment of sampling times between different nodes.

[0044] During the location observation period, street light nodes suspend the generation of new non-emergency dimming messages and temporarily suspend the relay forwarding of non-emergency dimming messages already in the message queue, while retaining the transmission rights for minimum safe lighting messages and fault alarm messages. Minimum safe lighting messages are used to restore basic lighting when road illuminance falls below the safe lower limit, and fault alarm messages are used to report street light driver failures, communication failures, and sensor failures.

[0045] The system records the transmit and receive status of the wireless communication unit when each sensing node collects positioning observation data, and discards positioning observation data in which the wireless communication unit is in dimming message transmission or relay forwarding status during the collection period. This method avoids using incomplete received signal strength obtained when the scanning time is occupied by dimming communication as normal positioning samples.

[0046] The Bluetooth received signal strength data, microwave velocity measurement data, and infrared target presence data with a time difference not exceeding the preset synchronization time difference are combined into an observation data group. When the number of effective observation data groups is lower than the number required for trajectory identification, the positioning observation period is extended until the preset maximum protection time is reached.

[0047] In this embodiment, the preset synchronization time difference is set to 100ms, the initial duration of the positioning observation period is set to 0.8s, and the preset maximum protection duration is set to 2s. When the number of valid observation data sets obtained within 0.8s is less than 5, the positioning observation period is extended in 0.2s increments until the number of valid observation data sets reaches 5 or the positioning observation period reaches 2s. If the trajectory confirmation condition cannot be met after the positioning observation period reaches 2s, it is handled as if the target trajectory has not been confirmed, increasing the brightness of streetlights on the common road segment and maintaining safe brightness for the branch streetlights corresponding to different candidate trajectories.

[0048] When updating candidate trajectories using positioning observation data, the actual observation feature sequences obtained during the positioning observation period are time-aligned with the expected observation feature sequences of each candidate trajectory. The observation matching degree of each candidate trajectory is determined based on the consistency of Bluetooth received signal strength deviation, sensing node passing sequence deviation, microwave velocity measurement deviation, and infrared target presence status.

[0049] The observation matching degree of the j-th candidate trajectory can be expressed as: In the formula, The actual Bluetooth received signal strength and the first The normalized deviation between the range of received signal strength corresponding to each candidate trajectory; The normalized deviation between the actual and expected order of passing through the nodes; For microwave velocimetry results and the first Normalized bias between the predicted velocities of the candidate trajectories; The degree of inconsistency in the state of the infrared target; , , and For the corresponding weights.

[0050] Specifically, the observation bias is calculated using the following normalized formula: in, This represents the actual Bluetooth received signal strength. For the first The expected received signal strength range corresponding to each candidate trajectory; when lie in At that time, ,otherwise, for The difference between the nearest boundary of the expected received signal strength range; For the reference deviation of received signal strength, this embodiment takes 20dB.

[0051] in, The actual sensing nodes pass through the sequence. For the first The expected sensing node sequence corresponding to each candidate trajectory. This represents the length of the longest common subsequence of two sequences.

[0052] in, The results are from microwave velocimetry. For the first The prediction speed corresponding to each candidate trajectory The maximum effective speed is preset according to the target type. When the infrared target's state is similar to the first... When the expected states corresponding to the candidate trajectories are consistent When inconsistent, .

[0053] Weight , , and All are non-negative numbers and satisfy: In engineering applications, The typical value range is 0.30 to 0.40. The typical value range is 0.25 to 0.35. The typical value range is 0.15 to 0.25. The typical value range is 0.10 to 0.20. In this embodiment, .

[0054] When the same candidate trajectory achieves the highest observation matching degree in three consecutive observation data sets, and the difference between its matching degree and the second highest observation matching degree reaches the trajectory confirmation threshold, the candidate trajectory is determined as the target trajectory. In this embodiment, the trajectory confirmation threshold is set to 0.15. Using three consecutive observation data sets for confirmation can prevent the target trajectory from immediately changing when a single received signal strength sample is affected by obstruction or multipath propagation.

[0055] If the candidate trajectory corresponding to the highest observation matching degree switches more than twice within 2 seconds, it is determined that the candidate trajectory has switched multiple times. In response to multiple switching of candidate trajectories, the lighting task of the common road segment is maintained, the target brightness of any branch road segment is not activated, and the number of basic effective observation data sets required for the next positioning observation period is increased from 5 sets to 7 sets. This avoids repeatedly turning on and off different branch streetlights when the prediction results jump between different branches.

[0056] S5. In response to the confirmation of the target trajectory, send the trajectory identifier corresponding to the target trajectory, so that the street light controller can call the issued candidate lighting tasks for continuous dimming; in response to the failure to confirm the target trajectory, make the street lights in the road sections that the candidate trajectories pass through brighter, and make the street lights in the branch road sections maintain a safe brightness.

[0057] The amount of data for the trajectory identifier is less than the amount of data for the candidate lighting tasks. After the target trajectory is confirmed, the gateway no longer resends the complete dimming parameters for each street light, but only sends the corresponding trajectory identifier. The street light controller retrieves candidate lighting tasks with the same trajectory identifier from its local task area and sequentially controls the street lights to brighten according to the corrected predicted arrival time and brightness change rate.

[0058] The road segments traversed by different candidate trajectories are designated as common road segments, and the road segments traversed by different candidate trajectories from their respective trajectory separation points are designated as branch road segments. When the target trajectory is not confirmed, the common road segments are brightened to meet the target traffic requirements, while each branch road segment maintains only the safe brightness determined based on the minimum road illuminance, rather than adjusting all candidate branches to the target brightness.

[0059] In this embodiment, the base brightness is set to 20% of the rated brightness of the streetlight, the safe brightness is set to 30% of the rated brightness, and the target brightness is set to 80% of the rated brightness. For roads with motor vehicle traffic, the target brightness can be increased to 90% of the rated brightness according to the road lighting level; for roads with only pedestrians, the target brightness can be reduced to 60% of the rated brightness. The safe brightness is always not lower than the brightness required to meet the minimum illuminance requirements of the road.

[0060] The task failure time for candidate lighting tasks is set to 2 seconds after the predicted departure time of the target from the corresponding streetlight illumination area. If no trajectory identifier is received before the task failure time, the streetlight controller does not execute the target brightness for the corresponding branch, but only maintains the safe brightness, and deletes the corresponding candidate lighting task after the task failure time is reached.

[0061] In response to the lack of a trajectory identifier before the task expires, the street light controller executes a safety lighting task and deletes branch lighting tasks that do not meet the activation conditions. The safety lighting task prioritizes ensuring continuous lighting at the trajectory separation point and its adjacent area, while limiting the lighting power of unconfirmed branch road sections.

[0062] Once the target trajectory is confirmed, the streetlights on the corresponding branches will brighten sequentially according to the predicted arrival time of the target; after the target passes, the brightness will gradually decrease according to the predicted departure time and the duration of brightness maintenance. Candidate lighting tasks for other branch sections will be cancelled or automatically deleted after the task expires.

[0063] When multiple targets exist within a road area, the candidate lighting tasks for each target are converted into lighting demand time intervals corresponding to each street light node. Each lighting demand time interval includes at least the predicted start time of brightness enhancement, the predicted start time of brightness reduction, the target type, the target brightness, and the associated trajectory identifier.

[0064] Overlapping lighting demand time intervals at the same street light node are merged into a joint lighting interval. The highest target brightness corresponding to different targets within the joint lighting interval is used as the execution brightness of the street light node. The earliest predicted arrival time is used as the basis for increasing brightness, and the latest predicted departure time is used as the basis for decreasing brightness.

[0065] For example, when the predicted trajectories of a pedestrian and a motor vehicle overlap in the same road section, the corresponding lighting brightness is not added together. Instead, a higher brightness that meets the lighting requirements for motor vehicle traffic is used, and the lighting is maintained until both the pedestrian and the motor vehicle leave the corresponding lighting area.

[0066] When the time interval between adjacent combined lighting zones is less than the time required for a streetlight to drop from its safe brightness to its base brightness and then back to its safe brightness, the adjacent combined lighting zones are merged. This method can avoid short-term brightness reduction processes between two adjacent targets that do not have any practical energy-saving significance.

[0067] Difference update messages are generated only when the start and end times of the joint lighting zone, the execution brightness, or the associated trajectory identifier changes. The street light controller then uses these difference update messages to modify the stored candidate lighting tasks, thereby avoiding the repeated issuance of complete dimming tasks for the same street light and overlapping targets.

[0068] For example, in this embodiment of the invention, an intersection with one entrance road and two branch roads is taken as an example. The target approaches the intersection along the entrance road, and a first candidate trajectory and a second candidate trajectory are generated based on the continuous position and motion state. The first candidate trajectory corresponds to the left branch, and the second candidate trajectory corresponds to the right branch. The two candidate trajectories form a trajectory separation point at the center of the intersection.

[0069] Before the target reaches the trajectory separation point, the control system generates candidate lighting tasks with first trajectory identifier and second trajectory identifier respectively, and sends the common road section lighting task and the differential dimming data of the two branches to the street light controller in advance.

[0070] When the target enters the vicinity of the trajectory identification location, the positioning and observation period begins, temporarily suspending non-emergency dimming messages and their Mesh relay forwarding. The control system continuously acquires Bluetooth received signal strength data and, in conjunction with microwave velocity measurement data and infrared target presence data, confirms the target's direction of movement.

[0071] When multiple consecutive observation data sets all point to the first candidate trajectory, only the first trajectory identifier is sent. The street light controller on the left branch calls the already stored first candidate lighting task and gradually increases the brightness according to the predicted arrival order of the target; the right branch does not receive a complete cancellation command, but maintains a safe brightness if it does not receive the second trajectory identifier, and deletes the second candidate lighting task after the task fails.

[0072] Therefore, the multiple lamp-by-lamp dimming messages that need to be sent at the moment of trajectory confirmation are reduced to a trajectory identification message, which not only protects the continuous positioning observation of the trajectory bifurcation area, but also avoids maintaining all candidate branches at the target brightness for a long time in order to prevent light leakage.

[0073] To verify the technical effect of the present invention, this embodiment adopts a discrete event simulation method to compare the present invention with the existing control method of brightening all candidate branches when the trajectory is not confirmed and sending lamp-by-lamp dimming messages during the positioning observation period.

[0074] The simulated road includes one common road segment and two candidate branches. Six 100W streetlights are installed on the common road segment and each candidate branch, for a total of 18 streetlights. The base brightness is 20% of the rated brightness, the safe brightness is 30% of the rated brightness, and the target brightness is 80% of the rated brightness. The uncertainty duration of the target trajectory follows a normal distribution with a mean of 3s, a standard deviation of 0.6s, and a range limited to 1.5–4.5s. The target illumination duration after trajectory confirmation is set to 7s.

[0075] The wireless communication network adopts a four-hop Bluetooth Mesh network. The time occupied by single-hop dimming message transmission and relay processing is set to 12ms, the positioning sampling frequency is set to 10Hz, and the missing proportion of random positioning samples when no dimming message transmission occurs is set to 3%. The existing control method sends dimming messages to 12 streetlights in two candidate branches during the positioning observation period, and adjusts both candidate branches to the target brightness while the trajectory is not confirmed. This invention completes the issuance of candidate lighting tasks before the positioning observation period, restricts non-emergency dimming messages during the positioning observation period, and sends a trajectory identifier after the trajectory is confirmed, so that the corresponding streetlight controller can call the stored candidate lighting tasks.

[0076] The simulation executed the target passage process 1000 times, and the results are as follows: The simulation results show that this invention reduces the number of dimming control messages during the positioning observation process by 91.7%, increases the proportion of effective positioning observation data by 18.34 percentage points, and shortens the time required to obtain continuous effective observation data by 35.9% by pre-issuing candidate lighting tasks before the start of the positioning observation period and sending only trajectory identifiers with small data volumes after trajectory confirmation. Simultaneously, by only brightening common road sections and maintaining safe brightness for candidate branches when the target trajectory is not confirmed, the lighting energy consumption for a single target passage process is reduced by 14.7%, and non-target candidate branches are prevented from being adjusted to the target brightness. The simulation results are consistent with the technical effects of this invention in reducing the impact of dimming communication on positioning observation, shortening the target trajectory confirmation time, and reducing ineffective lighting energy consumption.

[0077] Example 2 Please see Figure 2 This embodiment provides a low-carbon and energy-saving street light control system based on human and vehicle trajectory prediction, including a human and vehicle perception module, a trajectory prediction module, an observation period determination module, a candidate task generation module, a communication coordination module, and a street light controller.

[0078] The vehicle and pedestrian sensing module is used to acquire the continuous position and movement status of road targets. The module includes a Bluetooth positioning unit, a microwave sensing unit, and an infrared sensing unit. The Bluetooth positioning unit transmits positioning and sensing messages with the streetlight nodes via a Bluetooth Mesh network. The microwave sensing unit is used to acquire the target's distance and speed, and the infrared sensing unit is used to confirm whether the target has entered the streetlight illumination area.

[0079] The trajectory prediction module is used to generate candidate trajectories by combining road topology, and to determine trajectory break-off points, associated street light groups, and confidence levels. The trajectory prediction module can be installed at a road edge gateway or at a region controller that communicates with multiple road edge gateways.

[0080] The observation period determination module is used to determine the location observation period to be protected and the dimming execution period of each associated street light, and to determine whether the dimming message transmission period overlaps with the location observation period based on the expected transmission duration of the candidate lighting task.

[0081] The candidate task generation module is used to generate candidate lighting tasks with trajectory identifiers for each candidate trajectory, and to pre-issue the candidate lighting tasks to the street light controller before the start of the positioning observation period.

[0082] The communication coordination module is used to respond to the overlap between the positioning observation period and the dimming message transmission period, restrict the sending and relaying of non-emergency dimming messages during the positioning observation period, and send the corresponding trajectory identifier after the target trajectory is confirmed.

[0083] The street light controller is used to store candidate lighting tasks and, in response to receiving a trajectory identifier, calls the corresponding candidate lighting task for continuous dimming.

[0084] The street light controller includes a wireless communication unit, a local clock, a candidate task storage area, and a dimming interface. The wireless communication unit is used to receive candidate lighting tasks and trajectory identifiers. The candidate task storage area is used to store candidate lighting tasks according to the trajectory identifiers. The dimming interface is used to convert candidate lighting tasks into dimming signals that can be executed by the street light driver.

[0085] The dimming interface can be a DALI dimming interface, a 0-10V dimming interface, or a pulse width modulation interface. When using a DALI dimming interface, the street light controller generates the corresponding DALI brightness level and transmission time based on the target brightness and brightness change rate in the candidate lighting task.

[0086] In response to a wireless communication interruption, the street light controller continues to execute the active candidate lighting tasks and restores the street lights to a preset safe brightness after the candidate lighting tasks reach their expiration time. Therefore, even if a temporary communication interruption occurs after the trajectory markers are sent, the already illuminated road area will not suddenly lose its lighting.

[0087] This invention reduces the centralized dimming message after trajectory confirmation to a trajectory identifier by issuing candidate lighting tasks in advance before the arrival of the critical positioning observation period; it reduces the impact of dimming communication on the integrity and synchronization of positioning samples by restricting the sending and relaying of non-emergency dimming messages during the positioning observation period; and it reduces the invalid pre-brightening range and the number of repeated dimming times while meeting the road safety lighting requirements by brightening common road sections, maintaining safe brightness on unconfirmed branches, and brightening target branches according to the predicted arrival order.

[0088] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0089] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0090] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0091] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A low-carbon and energy-saving control method for streetlights based on pedestrian and vehicle trajectory prediction, characterized in that, include: S1. Obtain the continuous position and motion state of the road target, generate candidate trajectories by combining the road topology, and determine the trajectory separation point, associated street light group and confidence level of each candidate trajectory. S2. Determine the location observation period to be protected based on the credibility of the candidate trajectory and the estimated time of the target's arrival at the trajectory separation point; determine the dimming execution period based on the predicted time of the target's arrival at each associated street lighting area. S3. Generate candidate lighting tasks with trajectory identifiers for each candidate trajectory. The candidate lighting tasks include the brightness change order and activation conditions of the associated streetlights. Before the start of the positioning observation period, the candidate lighting tasks are pre-issued to the corresponding streetlight controllers according to the dimming execution period. S4. In response to the overlap between the positioning observation period and the dimming message transmission period in the shared wireless communication resources, restrict the transmission and relay forwarding of non-urgent dimming messages during the positioning observation period, and update the candidate trajectory using the obtained positioning observation data. S5. In response to the confirmation of the target trajectory, send the trajectory identifier corresponding to the target trajectory, so that the street light controller can call the candidate lighting task that has been issued to perform continuous dimming; In response to the failure to confirm the target trajectory, the streetlights on the road segments shared by the candidate trajectories are brightened, while the streetlights on the branch road segments are kept at a safe brightness. Determine the location observation period to be protected, including: Based on the sensing nodes passed by each candidate trajectory and the predicted distance between the target and each sensing node, a predictive observation feature sequence is generated for each candidate trajectory. The predictive observation feature sequence includes sensing node identifiers, Bluetooth received signal strength range, and target passing order. Compare the expected observation feature sequences of different candidate trajectories, and determine the position where the feature difference between at least two expected observation feature sequences first reaches a preset identifiable threshold as the trajectory identification position; Based on the estimated time of the target's arrival at the trajectory identification location, the number of effective positioning samples required to complete one trajectory identification, and the historical missing proportion of positioning samples, the start time and duration of the positioning observation period are determined so that the positioning observation period covers the positioning sampling process before and after the target arrives at the trajectory identification location.

2. The street light low-carbon energy-saving control method based on pedestrian and vehicle trajectory prediction according to claim 1, characterized in that, The generation of candidate trajectories by combining road topology includes: Road intersections, road entrances and exits, and road turning points are used as road connection nodes, and the roads between adjacent road connection nodes are used as directed road segments. A mapping relationship between each directed road segment and the street lighting area is established. Based on the target's current position, moving speed, and preset maximum acceleration and maximum deceleration, determine the target's reachable distance range in the predicted time domain; From the directed road segments that are connected to the current directed road segment of the target and intersect with the reachable distance range, the directed road segments that do not meet the road travel direction are eliminated to form candidate trajectories; The credibility of candidate trajectories is determined based on the lateral offset of the target relative to the candidate road entrance, the angle between the target's movement direction and the candidate road extension direction, and the continuity of the target's movement speed. The road connection nodes that correspond to different oriented road segments for the first time for different candidate trajectories are identified as trajectory separation points.

3. The street light low-carbon energy-saving control method based on pedestrian and vehicle trajectory prediction according to claim 1, characterized in that, The dimming execution period is the difference between the predicted time when the target enters the corresponding street light illumination area and the time it takes for the street light brightness to establish; The estimated transmission time of the candidate lighting task is determined based on the data volume of the candidate lighting task, the number of relay hops between the street light controller and the gateway, the single-hop message transmission time, the number of historical retransmissions, and the current message queue length. In response to the overlap between the dimming message transmission period formed according to the expected transmission duration and the positioning observation period, candidate lighting tasks are transmitted before the start of the positioning observation period in the order of dimming execution deadline from earliest to latest. For road segments traversed by different candidate trajectories, a common lighting task is issued only once, and the corresponding branch road segments' differential dimming data relative to the common lighting task are issued in each candidate lighting task.

4. The street light low-carbon energy-saving control method based on pedestrian and vehicle trajectory prediction according to claim 3, characterized in that, During the location observation period, the street light nodes suspend the generation of new non-emergency dimming messages and temporarily suspend the relay forwarding of non-emergency dimming messages that have entered the message queue, while retaining the transmission rights of minimum safe lighting messages and fault alarm messages. Record the transmit and receive status of the wireless communication unit when each sensing node collects positioning observation data, and remove positioning observation data in which the wireless communication unit is in the dimming message sending state or relay forwarding state during the collection period; The Bluetooth received signal strength data, microwave velocity measurement data, and infrared target presence data with a time difference not exceeding the preset synchronization time difference are combined into an observation data group. When the number of effective observation data groups is lower than the number required for trajectory identification, the positioning observation period is extended until the preset maximum protection time is reached.

5. The street light low-carbon energy-saving control method based on pedestrian and vehicle trajectory prediction according to claim 4, characterized in that, Update candidate trajectories using location observation data, including: The actual observation feature sequences obtained during the positioning observation period are time-aligned with the expected observation feature sequences of each candidate trajectory. The observation matching degree of each candidate trajectory is determined based on the deviation of Bluetooth received signal strength, the deviation of the passing order of sensing nodes, the deviation of microwave velocity measurement, and the consistency of the infrared target's existence status. When the same candidate trajectory has the highest observation matching degree in multiple consecutive observation data sets, and the difference between it and the second highest observation matching degree reaches the trajectory confirmation threshold, the candidate trajectory is determined as the target trajectory. When the candidate trajectory corresponding to the highest observation matching degree switches multiple times within a preset time period, the lighting task of the common road segment is maintained, the target brightness of any branch road segment is not activated, and the number of effective positioning samples required for the next positioning observation period is increased.

6. The street light low-carbon energy-saving control method based on pedestrian and vehicle trajectory prediction according to claim 3, characterized in that, The candidate lighting task also includes trajectory identifier, street light node address, predicted arrival time, initial brightness, safe brightness, target brightness, brightness change rate, brightness maintenance duration, and task failure time; After receiving candidate lighting tasks, the street light controller stores the candidate lighting tasks in the local task area and corrects the predicted arrival time based on the synchronization deviation between the local clock and the gateway clock. In response to receiving the trajectory identifier, the street light controller calls up the candidate lighting task with the same trajectory identifier from the local task area, and controls the street light to brighten sequentially according to the corrected predicted arrival time and brightness change rate. In response to the failure to receive a trajectory identifier before the task expires, the street light controller executes a safety lighting task and deletes branch lighting tasks that do not meet the activation conditions.

7. The street light low-carbon energy-saving control method based on pedestrian and vehicle trajectory prediction according to claim 6, characterized in that, When there are multiple targets in the road area, the candidate lighting tasks for each target are converted into lighting demand time intervals corresponding to each street light node. The overlapping lighting demand time intervals on the same street light node are merged into a joint lighting interval, and the highest target brightness corresponding to different targets within the joint lighting interval is used as the execution brightness of the street light node. The earliest predicted arrival time is used as the basis for increasing brightness, and the latest predicted departure time is used as the basis for decreasing brightness. When the time interval between adjacent combined lighting zones is less than the time required for a street light to decrease from a safe brightness to a base brightness and then recover to a safe brightness, the adjacent combined lighting zones shall be merged. Difference update messages are generated only when the start and end times of the combined lighting zone, the execution brightness, or the associated trajectory identifier changes, and the street light controller uses the difference update messages to modify the stored candidate lighting tasks.

8. A low-carbon and energy-saving control system for streetlights based on pedestrian and vehicle trajectory prediction, used to execute the low-carbon and energy-saving control method for streetlights based on pedestrian and vehicle trajectory prediction as described in claim 1, characterized in that, It includes a human and vehicle perception module, a trajectory prediction module, an observation period determination module, a candidate task generation module, a communication coordination module, and a street light controller; The human and vehicle perception module is used to acquire the continuous position and motion state of road targets; The trajectory prediction module is used to generate candidate trajectories by combining road topology, and to determine trajectory break-off points, associated street light groups, and confidence levels. The observation period determination module is used to determine the location observation period to be protected and the dimming execution period of each associated street light; The candidate task generation module is used to generate candidate lighting tasks with trajectory identifiers for each candidate trajectory, and to pre-send the candidate lighting tasks to the street light controller before the start of the positioning observation period. The communication coordination module is used to respond to the overlap between the positioning observation period and the dimming message transmission period, restrict the sending and relaying of non-emergency dimming messages during the positioning observation period, and send the corresponding trajectory identifier after the target trajectory is confirmed. The street light controller is used to store candidate lighting tasks and, in response to receiving a trajectory identifier, calls the corresponding candidate lighting task for continuous dimming.

9. A low-carbon energy-saving control system for streetlights based on pedestrian and vehicle trajectory prediction according to claim 8, characterized in that, The vehicle and pedestrian sensing module includes a Bluetooth positioning unit, a microwave sensing unit, and an infrared sensing unit. The Bluetooth positioning unit transmits positioning and sensing messages with the street light node through a Bluetooth Mesh network. The microwave sensing unit is used to obtain the distance and speed of the target. The infrared sensing unit is used to confirm whether the target has entered the street light illumination area. The street light controller includes a wireless communication unit, a local clock, a candidate task storage area, and a dimming interface. The wireless communication unit is used to receive candidate lighting tasks and trajectory identifiers. The candidate task storage area is used to store candidate lighting tasks according to the trajectory identifiers. The dimming interface is used to convert candidate lighting tasks into dimming signals that can be executed by the street light driver. In response to a wireless communication interruption, the street light controller continues to execute the active candidate lighting tasks and restores the street lights to the preset safe brightness after the candidate lighting tasks reach the task failure time.

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