LoRa-based mobile robot cluster scheduling communication system

Abstract

The application discloses a mobile robot cluster scheduling communication system based on LoRa, wherein the system comprises a scheduling server, a LoRa gateway and a plurality of mobile robots, the scheduling server is connected with the plurality of mobile robots in wireless communication by taking the LoRa gateway as a relay, the scheduling server is used for managing an interface for connecting the plurality of mobile robots with an upper system, is further used for scheduling data processing of the plurality of mobile robots and management and configuration of the LoRa gateway, the LoRa gateway is used for multi-channel transceiving and temporary storage of scheduling data, and is used for configuring the number of the plurality of mobile robots and establishing a communication network, and the plurality of mobile robots are used for uploading running data to the LoRa gateway and receiving scheduling instructions from the LoRa gateway. In the embodiment of the application, free networking is realized, the layout is flexible, good communication stability can be maintained in an electromagnetic interference environment, and the system has the advantages of lower power consumption and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication technology, in particular to a LoRa-based mobile robot cluster scheduling communication system. BACKGROUND

[0002] Mobile robots have a large range of motion, and generally use wireless communication to communicate with the rear console or scheduling system. Currently, the communication network for mobile robot cluster scheduling mainly uses technologies including 4G / 5G cellular mobile communication network, Bluetooth network, WiFi network, ZigBee network, UWB network, and LPWAN network. The advantages of the 4G / 5G cellular mobile communication network are fast speed, low latency, high stability, and high reliability. The disadvantages are high equipment cost, high cost, high power consumption, and the need for network operation to provide equipment support. The advantages of the Bluetooth network are fast speed, low power consumption, and high security. The disadvantages are few network nodes, small network scale, and unsuitability for multi-point control. The advantages of the WiFi network are good flexibility and mobility, and convenient deployment. The disadvantages are susceptibility to interference, low transmission rate, short transmission distance, and poor security. The advantages of the ZigBee network are high security, low power consumption, strong networking capability, large capacity, and long battery life. The disadvantages are high cost, poor anti-interference performance, and short communication distance. The advantages of the UWB network are strong anti-multipath capability, high positioning accuracy, high timestamp accuracy, strong electromagnetic compatibility, and high energy efficiency. The disadvantages are signal susceptibility to obstacles and high equipment cost. The advantages of the LPWAN network are large network capacity, low power consumption, strong signal penetration capability, stable high-speed mobile signal, and the ability to locate and communicate over long distances. The disadvantage is low transmission rate.

[0003] LoRa (Long Range Radio) combines digital signal processing and forward error correction coding technology, and is a low-power, long-range wireless communication technology compared with other communication networks. Through multi-target parameter optimization means, it realizes the unification of low power consumption, long distance, and robustness requirements. This network technology is easy to deploy and apply to mobile robot cluster scheduling environments. The present application builds a multi-node communication network based on multi-target parameter optimization LoRa technology, which can adapt to harsh industrial environments, effectively perform wireless long-distance transmission of control instructions and monitoring data, and realize real-time interaction between mobile robots and rear scheduling servers. However, traditional LoRa technology has mutual contradictions in signal frequency, transmission distance, and power consumption, and cannot adjust network parameters according to application scenarios, resulting in that the network performance cannot be fully utilized. SUMMARY

[0004] The present application aims at overcoming the deficiencies of the prior art, and provides a LoRa-based mobile robot cluster scheduling communication system, which realizes free networking based on a LoRa gateway, has flexible layout, and can maintain good communication stability in an electromagnetic interference environment; and has the advantages of lower power consumption, longer communication distance, etc.

[0005] To solve the above technical problems, the present application provides a LoRa-based mobile robot cluster scheduling communication system, characterized in that the system comprises a scheduling server, a LoRa gateway and a plurality of mobile robots, the scheduling server is wirelessly connected to the plurality of mobile robots through the LoRa gateway as a relay.

[0006] The scheduling server is configured to manage the interface of the plurality of mobile robots and an upper system, and to process scheduling data of the plurality of mobile robots and manage and configure the LoRa gateway.

[0007] The LoRa gateway is configured to perform multi-channel transceiving and temporary storage of scheduling data, and to configure the number of the plurality of mobile robots and form a communication network.

[0008] The plurality of mobile robots are configured to upload running data to the LoRa gateway and receive scheduling instructions from the LoRa gateway.

[0009] Optionally, the LoRa gateway, the scheduling server and the plurality of mobile robots perform data transmission based on MQTT and HTTPS protocols, and perform ID identification and connection processing of the plurality of mobile robots based on TCP / IP protocol.

[0010] Optionally, when the LoRa gateway is connected to the plurality of mobile robots to form a network, the LoRa frequency points of the plurality of mobile robots are hopped to the same channel to form a self-organized communication network of the LoRa gateway and the plurality of mobile robots.

[0011] Optionally, the scheduling data processing of the scheduling server and the plurality of mobile robots comprises:

[0012] Downlink processing of scheduling data of the scheduling server and the plurality of mobile robots.

[0013] Uplink processing of scheduling data of the scheduling server and the plurality of mobile robots.

[0014] Optionally, the downlink processing of scheduling data of the scheduling server and the plurality of mobile robots comprises:

[0015] After the dispatch server, the LoRa gateway and the plurality of mobile robots are powered on, the dispatch server sequentially initializes the LoRa gateway and the plurality of mobile robots;

[0016] After the initialization is completed, the dispatch server distributes channels and working tasks of the plurality of mobile robots based on a preset algorithm;

[0017] The dispatch server plans a running path of each mobile robot in the plurality of mobile robots based on a running path planning algorithm;

[0018] Based on the working task distribution result and the running path, a motion control instruction of each mobile robot corresponding to the plurality of mobile robots is generated, the remote control instruction is encrypted to form an encrypted remote control instruction;

[0019] The encrypted remote control instruction is sent to the plurality of mobile robots through the LoRa gateway based on the channel distribution result;

[0020] After the plurality of mobile robots receives the encrypted motion control instruction, the encrypted motion control instruction is decrypted, and the decrypted motion control instruction is input into a robot controller for execution.

[0021] Optionally, the dispatch server distributes channels and working tasks of the plurality of mobile robots based on a preset algorithm, comprising:

[0022] The dispatch server distributes channels of the plurality of mobile robots based on a running frequency hopping algorithm;

[0023] The dispatch server distributes working tasks of the plurality of mobile robots based on a running scheduling algorithm.

[0024] Optionally, the uplink processing of the dispatch data of the dispatch server and the plurality of mobile robots comprises:

[0025] The plurality of mobile robots respectively collect robot running data to obtain running state data;

[0026] The plurality of mobile robots encrypt the collected running state data to obtain encrypted running state data;

[0027] The plurality of mobile robots send the encrypted running state data to the LoRa gateway, and the LoRa gateway uploads the encrypted running state data to the dispatch server for dispatch based on a channel of a specific frequency;

[0028] The scheduling server schedules decryption processing on the encrypted running state data, and performs scheduling decision processing based on a decryption processing result and work tasks of a plurality of mobile robots.

[0029] Optionally, the LoRa gateway, in operation, optimizes power consumption of the LoRa network based on a multi-objective parameter optimization algorithm, wherein power energy loss of the LoRa gateway is related to data transmission rate, air transmission time;

[0030] The multi-objective parameter optimization algorithm for optimizing power consumption of the LoRa network includes constructing a formula as follows:

[0031] Q=f Q (DR,T packet )=f Q (SF,CR,BW,n preamble ,PL,DE,H).

[0032] In the formula, Q represents power consumption, f Q (.) represents a power consumption function, DR represents data transmission rate; T packet represents control transmission data; SF represents a spread factor; BW represents bandwidth; CR represents a coding rate; n preamble represents preamble length of a data packet; PL represents effective payload byte number; DE represents data speed optimization enabled by a service, and is 0 when disabled; and H represents whether a header is enabled, and is 1 when the header does not exist.

[0033] In the formula, Q represents power consumption, f Q (.) represents a power consumption function, DR represents data transmission rate; T packet represents control transmission data; SF represents a spread factor; BW represents bandwidth; CR represents a coding rate; n preamble represents preamble length of a data packet; PL represents effective payload byte number; DE represents data speed optimization enabled by a service, and is 0 when disabled; and H represents whether a header is enabled, and is 1 when the header does not exist.

[0034]

[0035] The above formula is simplified as follows:

[0036] Q=f Q (DR,T packet )=f Q (SF,CR,BW).

[0037] Data transmission distance is related to power consumption, so the power supply voltage is a fixed value, the antenna gain is 5Dbi, and the transmission power is 20dbm, so the farthest distance of data transmission of the LoRa gateway is represented by the following formula:

[0038] D=f D (L)=f D (SF,CR,BW).

[0039] In the formula, D represents the farthest distance of data transmission, f D (.) represents a farthest distance of data transmission function; and an approximate function of robustness of data transmission is:

[0040] R=f R (SF, CR, BW);

[0041] wherein, R represents the robustness of data transmission, f R (.) represents the data transmission robustness function; in the LoRa gateway, different combinations of LoRa parameters set have an impact on data transmission distance, power consumption and robustness, that is:

[0042]

[0043] wherein, F represents the LoRa network parameter optimization objective function, f Q ', f D ', f R ' represents f Q , f D , f R corresponding normalization factor, -w1+w2+w3=1; the parameters SF, BW and CR in the optimization function are optimization parameters, and w1, w2 and w3 are weighting coefficients; then the constraint condition is:

[0044]

[0045] Based on the normalization method, the multi-objective optimization problem is changed into a single-objective optimization problem, and the optimization target is the maximum value of the dimensionless number F.

[0046] Optionally, the LoRa gateway is packaged as a LoRa data packet, and the LoRa data packet comprises a preamble, an optional header and a mobile robot data payload; the transmission time of the LoRa data packet is composed of the transmission time of the preamble and the payload transmission time.

[0047] Optionally, the LoRa gateway performs encryption processing on the transmitted data based on the LoRa WAN protocol security mechanism.

[0048] In the embodiment of the application, the LoRa gateway is freely networked through the LoRa gateway ad hoc networking mode, and the network is flexible; in a weak signal environment and an electromagnetic interference environment, good communication stability can be maintained, and the technology can be applied to a large area scene; through parameter optimization of the LoRa gateway, the power consumption of the device can be greatly reduced while increasing the transmission distance, and communication can be realized at a smaller cost; through the TCP / IP protocol connection, the demand of large-scale scheduling can be met; the LoRa WAN protocol security mechanism is used to enhance the security of control communication. BRIEF DESCRIPTION OF DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0050] Figure 1 is a structural composition schematic diagram of a LoRa-based mobile robot cluster scheduling communication system in an embodiment of the present application.

[0051] Figure 2 is a downlink flow process schematic diagram of scheduling data in an embodiment of the present application.

[0052] Figure 3 is an uplink flow process schematic diagram of scheduling data in an embodiment of the present application. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments only constitute some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0054] EMBODIMENT

[0055] Please refer to Figure 1 , Figure 1 is a structural composition schematic diagram of a LoRa-based mobile robot cluster scheduling communication system in an embodiment of the present application.

[0056] As Figure 1 shown, a LoRa-based mobile robot cluster scheduling communication system, the system comprises a scheduling server, a LoRa gateway and a plurality of mobile robots, the scheduling server takes the LoRa gateway as a relay and is wirelessly connected with the plurality of mobile robots; the scheduling server is used for management of an upper system interfacing interface of the plurality of mobile robots; is also used for scheduling data processing of the plurality of mobile robots and management and configuration of the LoRa gateway; the LoRa gateway is used for multi-channel transceiving and temporary storage of scheduling data, and is used for configuration of the number of the plurality of mobile robots and construction of a communication network; the plurality of mobile robots are used for uploading running data to the LoRa gateway and receiving scheduling instructions from the LoRa gateway.

[0057] Specifically, the system comprises a scheduling server, a LoRa gateway and a plurality of mobile robots, wherein the scheduling server is connected with the plurality of mobile robots through the LoRa gateway; wherein the scheduling server is the upper layer, the plurality of mobile robots are the lower layer, and the LoRa gateway is the intermediate layer; the scheduling server is responsible for the management of the interface of the robot and the upper system, the processing of the scheduling data of the robot, and the management and configuration of the LoRa gateway; the LoRa gateway is responsible for the multi-channel transmission and temporary storage of the scheduling data, and one or more LoRa gateways can be configured according to the number of scheduling robots; the mobile robot is responsible for uploading the robot operation data to the LoRa gateway and receiving the scheduling instructions from the LoRa gateway.

[0058] In the system, there are corresponding software modules, specifically interface module, scheduling module, algorithm module, LoRa communication module, motion control module and data acquisition module; wherein the interface module, the scheduling module and the algorithm module run in the scheduling server; the LoRa communication module runs in the LoRa gateway; the motion control module and the data acquisition module run in the robot terminal.

[0059] In the implementation process of the present application, the LoRa gateway and the scheduling server and the plurality of mobile robots perform data transmission based on MQTT and HTTPS protocols, and perform ID identification and connection processing on the plurality of mobile robots based on TCP / IP protocol.

[0060] Specifically, the LoRa gateway and the scheduling server and the plurality of mobile robots perform data transmission by using MQTT and HTTPS protocols; and the plurality of mobile robots are identified and connected by TCP / IP protocol.

[0061] In the implementation process of the present application, when the LoRa gateway and the plurality of mobile robots are connected to form a network, the LoRa frequency points of the plurality of mobile robots are hopped to the same channel to form a self-organizing communication network of the LoRa gateway and the plurality of mobile robots.

[0062] Specifically, when the LoRa gateway is connected with a plurality of mobile robots to form a network, the LoRa frequency points of the plurality of mobile robots are hopped to the same channel, so as to realize the frequency rendezvous between the mobile robots, thereby forming a self-organizing communication network.

[0063] In the implementation process of the present application, the scheduling data processing of the scheduling server and the plurality of mobile robots comprises: downlink processing of the scheduling data of the scheduling server and the plurality of mobile robots; uplink processing of the scheduling data of the scheduling server and the plurality of mobile robots.

[0064] Specifically, please refer to Figure 2 and Figure 3 ; Figure 2 is a downlink process schematic diagram of scheduling data in an embodiment of the present application; Figure 3 is an uplink process schematic diagram of scheduling data in an embodiment of the present application.

[0065] As shown in Figure 2 , the downlink processing of the scheduling data between the scheduling server and the plurality of mobile robots comprises:

[0066] S21: After the scheduling server, the LoRa gateway and the plurality of mobile robots are powered on, the scheduling server sequentially performs initialization processing on the LoRa gateway and the plurality of mobile robots;

[0067] S22: After the initialization is completed, the scheduling server performs allocation processing on the channels and work tasks of the plurality of mobile robots based on a preset algorithm;

[0068] S23: The scheduling server plans the running path of each mobile robot in the plurality of mobile robots based on a running path planning algorithm;

[0069] S24: Based on the work task allocation processing result and the running path, a motion control instruction corresponding to each mobile robot of the plurality of mobile robots is generated, the remote control instruction is encrypted to form an encrypted remote control instruction;

[0070] S25: Based on the channel allocation processing result, the encrypted remote control instruction is sent to the plurality of mobile robots through the LoRa gateway;

[0071] S26: After the plurality of mobile robots receives the encrypted motion control instruction, the encrypted motion control instruction is decrypted and input into a robot controller for execution.

[0072] Meanwhile, when the scheduling server performs allocation processing on the channels and work tasks of the plurality of mobile robots based on a preset algorithm, the scheduling server performs allocation processing on the channels of the plurality of mobile robots based on a running frequency hopping algorithm; the scheduling server performs allocation processing on the work tasks of the plurality of mobile robots based on a running scheduling algorithm.

[0073] Through the above downlink data processing, the control instruction issued by the scheduling server is forwarded to the mobile robot through the LoRa gateway, and the mobile robot performs corresponding actions after receiving the scheduling instruction.

[0074] As shown in Figure 3 , the uplink processing of the scheduling data between the scheduling server and the plurality of mobile robots comprises:

[0075] S31: The plurality of mobile robots respectively perform robot running data collection and processing to obtain running state data;

[0076] S32: The plurality of mobile robots encrypt the collected running state data to obtain encrypted running state data;

[0077] S33: The plurality of mobile robots send the encrypted running state data to the LoRa gateway, and the LoRa gateway uploads the encrypted running state data to the scheduling server based on a channel of a specific frequency for scheduling;

[0078] S34: The scheduling server decrypts the encrypted running state data and makes scheduling decision based on the decryption result and the work tasks of the plurality of mobile robots.

[0079] Through the above uplink data processing, the mobile robot running data collected by the mobile robot terminal is sent to the scheduling server through the LoRa gateway. After receiving the collected data, the scheduling server displays the state of the mobile robot in real time through the control interface of the display, and decides the next action of the mobile robot according to the working state of the mobile robot.

[0080] In the specific implementation process of the present application, when the LoRa gateway is working, the power consumption of the LoRa network is optimized based on a multi-objective parameter optimization algorithm, wherein the power energy loss of the LoRa gateway is related to the data transmission rate and the air transmission time;

[0081] The multi-objective parameter optimization algorithm for optimizing the power consumption of the LoRa network includes constructing the following formula:

[0082] Q=f Q (DR,T packet )=f Q (SF,CR,BW,n preamble ,PL,DE,H);

[0083] In the formula, Q represents power consumption, f Q (.) represents the power consumption function, DR represents the data transmission rate; T packet represents the control transmission data; SF represents the spread factor; BW represents the bandwidth; CR represents the coding rate; n preamble represents the preamble length of the data packet; PL represents the number of effective load bytes; DE represents the data speed optimization enabled by the service, which is 0 when disabled; H represents whether the header is enabled, which is 1 when the header does not exist;

[0084] Wherein, the data structure is fixed as:

[0085]

[0086] The above formula is simplified as:

[0087] Q = f Q (DR, T packet ) = f Q (SF, CR, BW);

[0088] The data transmission distance is related to the power consumption, so the power supply voltage is a fixed value, the antenna gain is 5Dbi, and the transmission power is 20dbm, so the farthest distance of data transmission of the LoRa gateway is represented by the following formula:

[0089] D = f D (L) = f D (SF, CR, BW);

[0090] Where D represents the farthest distance of data transmission, f D (.) represents the farthest distance of data transmission function; then the approximate function of the robustness of data transmission is:

[0091] R = f R (SF, CR, BW);

[0092] In the LoRa gateway, different combinations of LoRa parameters have an impact on data transmission distance, power consumption and robustness, that is:

[0093]

[0094] Where F represents the LoRa network parameter optimization objective function, f Q ', f D ', f R ' represent the normalization factors corresponding to f Q , f D , f R , -w1+w2+w3=1; the parameters SF, BW, CR in the optimization function are optimization parameters, and w1, w2, w3 are weighting coefficients; then the constraint condition is:

[0095]

[0096] Based on the normalization method, the multi-objective optimization problem is changed into a single-objective optimization problem, and the optimization target is the maximum value of the dimensionless number F.

[0097] Specifically, in order to reduce the power consumption of the communication system, the power consumption of the LoRa network is optimized by using multi-objective parameter optimization means, and the power energy loss of the LoRa terminal is actually related to the data transmission rate and air transmission time.

[0098] The formula constructed when optimizing the processing is as follows:

[0099] Q=f Q (DR,T packet )=f Q (SF,CR,BW,n preamble ,PL,DE,H);

[0100] In the formula, Q represents power consumption, f Q (.) represents a power consumption function, DR represents a data transmission rate; T packet represents control transmission data; SF represents a spread spectrum factor; BW represents a bandwidth; CR represents a coding rate; n preamble represents a preamble length of a data packet; PL represents a number of effective load bytes; DE represents a data speed optimization enabled by a service, and is 0 when disabled; and H represents whether a header is enabled, and is 1 when the header does not exist.

[0101] The data structure is fixed as follows:

[0102]

[0103] The above formula is simplified as follows:

[0104] Q=f Q (DR,T packet )=f Q (SF,CR,BW);

[0105] The data transmission distance is related to power consumption, and there are many factors affecting the transmission distance. The transmission rate and the receiving sensitivity are mainly considered to affect the transmission distance, the power supply voltage is taken as a fixed value, the antenna gain is 5Dbi, and the transmission power is 20dbm. Then, the farthest distance of data transmission of the LoRa gateway is represented by the following formula:

[0106] D=f D (L)=f D (SF,CR,BW);

[0107] In the formula, D represents the farthest distance of data transmission, f D (.) represents a farthest distance of data transmission function; and then, the approximate function of the robustness of data transmission is as follows:

[0108] R=f R (SF,CR,BW);

[0109] In the formula, R represents the robustness of data transmission, f R(.) represents a data transmission robustness function; in combination with the above analysis, in the LoRa gateway, different combinations of LoRa parameters have an impact on data transmission distance, power consumption and robustness, and the optimal system performance needs to realize the lowest power consumption, the farthest transmission distance and the strongest robustness, that is:

[0110]

[0111] Wherein, F represents the LoRa network parameter optimization objective function, f Q ′, f D ′, f R ′ represents f Q , f D , f R The corresponding normalization factor is-w1+w2+w3=1; the parameters SF, BW and CR in the optimization function are optimization parameters, and w1, w2 and w3 are weighting coefficients; then the constraint condition is:

[0112]

[0113] Based on the normalization method, the multi-objective optimization problem is changed into a single-objective optimization problem, and the optimization target is the maximum value of the dimensionless number F. There are various algorithms for solving the multi-objective optimal parameter selection problem, such as ant colony algorithm, simulated annealing algorithm, grey wolf algorithm and improved genetic algorithm.

[0114] In the specific implementation process of the present application, the LoRa gateway is encapsulated as a LoRa data packet, the LoRa data packet comprises a preamble, an optional header and a mobile robot payload; the transmission time of the LoRa data packet is composed of the transmission time of the preamble and the transmission time of the payload.

[0115] The LoRa data packet structure is mainly composed of preamble, optional header, mobile robot data payload, the transmission time of the LoRa data packet is composed of the transmission time of the preamble and the transmission time of the payload. (1) The preamble is used to keep the data synchronization of the receiver, the length of the preamble contained in each data packet can be completed by the setting of the register, generally the length is 12 characters, and the length of the preamble can also be extended by programming. The setting range of the preamble is relatively wide, which can reach 85535 bytes, and different lengths of the preamble can be set according to the system demand. When the sequencer polling detects the preamble with the same length as the set value, the interrupt signal starts to be sent, the sequencer is closed, and the receiving mode is opened and kept. (2) The header includes two different modes, one is the explicit mode and the other is the implicit mode, the user can select different header forms by setting the register. The explicit header includes payload information, previous error correction coding rate and CRC check information, if such information is clear during development, the implicit header can be selected to reduce the data transmission time. (3) The value of the register Packet Format can change the length of the data packet, when the register is set to 0 and the value of Payload Length is not 0, the length of the data packet is fixed; when Packet Format is set to 1, the data packet is a variable length data packet.

[0116] In the embodiment, the LoRa gateway encrypts the transmitted data based on a LoRa WAN protocol security mechanism.

[0117] Specifically, the data transmission security mechanism is as follows: when the LoRa terminal needs to be networked, the following security information needs to be provided: a global terminal device ID (Dev EUI) uniquely identifying the terminal device, a global application unique application ID (APP EUI) stored in the terminal device, and an AES-encrypted 128-bit application session key (App key). The application session key is assigned to the terminal device by the program owner, and according to different network entry modes, the application session key is derived from an independent root key controlled by the program provider or directly assigned by the program provider. In transmission, LoRa WAN uses a static root key and a dynamically generated session key, and the encryption of LoRa is different for different network entry modes. When the network entry mode is OTAA (Over-the-Air-Activation), the root key existing when the network is connected generates a dynamic session key, and the constantly updated session key makes this network entry mode have higher security and can better protect the air communication. When the network entry mode is ABP (Activation-by-Personalization), the device will not be equipped with a root key, but will only be assigned a fixed and unchanging session key, and its security performance is lower than that of the OTAA mode.

[0118] In the embodiments of the present application, the LoRa gateway ad hoc networking mode is used for free networking, and the network is flexible to deploy. In a weak signal environment or an electromagnetic interference environment, good communication stability can be maintained, and the technology can be applied to large-area scenes. Through parameter optimization of the LoRa gateway technology, the transmission distance can be increased while the power consumption of the device is greatly reduced, and communication can be realized at a small cost. Through TCP / IP protocol connection, the demand of large-scale scheduling can be met. The security of control communication is enhanced by using the LoRa WAN protocol security mechanism.

[0119] Those skilled in the art can understand that all or part of the steps in the above-mentioned embodiments can be completed by programs instructing related hardware, and the programs can be stored in a computer readable storage medium, which can include read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk, etc.

[0120] In addition, the above describes in detail the LoRa-based mobile robot cluster scheduling communication system provided by the embodiment of the application, the principle and implementation manner of the application are described by using specific examples in the text, and the above embodiment description is only used to help understand the method of the application and the core idea thereof; meanwhile, for those skilled in the art, the specific implementation manner and application range can be changed according to the idea of the application, and the above description should not be understood as a limitation on the application.

Claims

1. A LoRa-based mobile robot swarm scheduling and communication system, characterized in that, The system includes: a scheduling server, a LoRa gateway, and several mobile robots. The scheduling server uses the LoRa gateway as a relay to establish a wireless communication connection with the several mobile robots. The scheduling server is used to manage the interfaces between the plurality of mobile robots and the host system; it is also used for the scheduling data processing of the plurality of mobile robots and the management and configuration of the LoRa gateway. The LoRa gateway is used for scheduling multi-channel data transmission and reception and temporary storage, and for configuring the number of mobile robots and building a communication network. The aforementioned mobile robots are used to upload operational data to the LoRa gateway and receive scheduling instructions from the LoRa gateway; When the LoRa gateway is working, it optimizes the power consumption of the LoRa network based on a multi-objective parameter optimization algorithm, wherein the power consumption of the LoRa gateway is related to the data transmission rate and data transmission time. The power consumption optimization algorithm based on multi-objective parameters for LoRa networks includes the following formula: ； In the formula, Indicates power consumption. Represents the power consumption function. Indicates the data transmission rate; Indicates data transmission time; Indicates the spreading factor; Indicates bandwidth; Indicates the coding rate; Indicates the length of the preamble in the data packet; Indicates the number of bytes of payload; This indicates that data speed optimization is enabled for the service; a value of 0 indicates that it is disabled. This indicates whether headers are enabled. A value of 1 indicates that headers are not enabled. The data structure is fixed as follows: ； The above formula can be simplified to: ； Since data transmission distance is related to power consumption, assuming a fixed power supply voltage, an antenna gain of 5 dBi, and a transmit power of 20 dBm, the maximum data transmission distance of the LoRa gateway can be expressed by the following formula: ； in, Indicates the farthest distance of data transmission. Let the function represent the furthest distance of data transmission; then, the approximate function for the robustness of data transmission is: ； in, Indicates the robustness of data transmission. This represents a data transmission robustness function; in the LoRa gateway, different combinations of LoRa parameters affect data transmission distance, power consumption, and robustness, namely: ； in, This represents the objective function for optimizing LoRa network parameters. , , express , , The corresponding normalization factor, The parameters SF, BW, and CR in the optimization function are the optimization parameters. , , Let be the weighting coefficients; then the constraint conditions are: ； The multi-objective optimization problem is transformed into a single-objective optimization problem based on the normalization method, with the optimization objective being a dimensionless numerical value. F The maximum value.

2. The mobile robot cluster scheduling and communication system according to claim 1, characterized in that, The LoRa gateway transmits data with the scheduling server and the plurality of mobile robots based on MQTT and HTTPS protocols, and performs ID identification and connection processing for the plurality of mobile robots based on TCP / IP protocol.

3. The mobile robot cluster scheduling and communication system according to claim 1, characterized in that, When the LoRa gateway connects to the plurality of mobile robots to form a network, the LoRa frequency points of the plurality of mobile robots are hopped to the same channel, forming a self-organized communication network between the LoRa gateway and the plurality of mobile robots.

4. The mobile robot cluster scheduling and communication system according to claim 1, characterized in that, The scheduling server and the scheduling data processing of the plurality of mobile robots include: Downlink processing of scheduling data between the scheduling server and the plurality of mobile robots; The scheduling server and the scheduling data of the several mobile robots are processed uplink.

5. The mobile robot cluster scheduling and communication system according to claim 4, characterized in that, Downlink processing of scheduling data between the scheduling server and the plurality of mobile robots includes: After the scheduling server, the LoRa gateway, and the plurality of mobile robots are powered on, the scheduling server performs initialization processing on the LoRa gateway and the plurality of mobile robots in sequence. After initialization is complete, the scheduling server allocates channels and tasks to the mobile robots based on a preset algorithm. The scheduling server plans the running path of each of the several mobile robots based on the running path planning algorithm; Based on the task allocation processing results and the running path, motion control instructions are generated for each of the several mobile robots. The motion control instructions are then encrypted to form encrypted motion control instructions. Based on the channel allocation processing results, the encrypted motion control commands are sent to the plurality of mobile robots through the LoRa gateway; After receiving the encrypted motion control command, the mobile robots decrypt it and input the decrypted motion control command into the robot controller for execution.

6. The mobile robot cluster scheduling and communication system according to claim 5, characterized in that, The scheduling server allocates channels and tasks to the plurality of mobile robots based on a preset algorithm, including: The scheduling server allocates channels for the various mobile robots based on a frequency hopping algorithm. The scheduling server allocates and processes the work tasks of the mobile robots based on the running scheduling algorithm.

7. The mobile robot cluster scheduling and communication system according to claim 4, characterized in that, The uplink processing of scheduling data between the scheduling server and the plurality of mobile robots includes: The aforementioned mobile robots each collect and process robot operation data to obtain operation status data; The mobile robots encrypt the collected operating status data to obtain encrypted operating status data. The mobile robots send encrypted operating status data to the LoRa gateway, and the LoRa gateway uploads the encrypted operating status data to the scheduling server for scheduling based on a specific frequency channel. The scheduling server decrypts the encrypted running status data and makes scheduling decisions based on the decryption results and the work tasks of several mobile robots.

8. The mobile robot cluster scheduling and communication system according to claim 1, characterized in that, The data passing through the LoRa gateway is encapsulated into LoRa data packets, which consist of a preamble, an optional header, and a mobile robot data payload. The transmission time of the LoRa data packets consists of the transmission time of the preamble and the transmission time of the payload.

9. The mobile robot cluster scheduling and communication system according to claim 1, characterized in that, The LoRa gateway encrypts the transmitted data based on the LoRa WAN protocol security mechanism.

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