A control method and control system for an intelligent logistics vehicle

Abstract

This invention discloses a control method and control system for an intelligent logistics vehicle, comprising: S1, receiving a first data packet sent by the intelligent logistics vehicle; S2, buffering the first data packet in a first receiving window of a first logical entity, wherein the first data packet has a first packet sequence number; S3, the first logical entity determining whether the first data packet includes a specific segment, wherein the specific segment includes the location information of the intelligent logistics vehicle; S4, if the first logical entity determines that the first data packet includes the specific segment, then the first logical entity delivers only the first data packet to a location information processing entity. This method is executed by a control terminal and eliminates the need to wait for previously lost or delayed data packets, thereby significantly improving the real-time performance of intelligent logistics vehicle location data processing and system communication efficiency.

Description

Technical Field

[0001] This invention relates to the field of Internet of Things (IoT) data processing technology, and in particular to a control method and control system for an intelligent logistics vehicle. Background Technology

[0002] Intelligent logistics vehicles are unmanned handling equipment that integrates navigation, autonomous control and task execution functions, and have become a key component of modern intelligent logistics systems. Furthermore, intelligent logistics vehicles have evolved from early magnetically guided automated guided vehicles (AGVs) to autonomous mobile robots (AMRs) with stronger environmental perception and decision-making capabilities.

[0003] The navigation and route planning of intelligent logistics vehicles rely on communication between the intelligent logistics vehicle and the control terminal. That is, data interaction between the intelligent logistics vehicle and the control terminal is achieved through mobile communication technology. However, when the communication quality is poor, the problem of untimely location reporting by the intelligent logistics vehicle often occurs.

[0004] like Figure 1 The receive window size of the MAC entity (i.e., the media access control entity) is set to 5. When the MAC entity has correctly received two data packets with sequence numbers 1 and 2, it will buffer these two data packets in the positions with corresponding labels 1 and 2 in the receive window. If the MAC entity has not correctly received the data packet with sequence number 0, the MAC entity will continue to wait for the retransmission of the data packet with sequence number 0.

[0005] like Figure 2 When the MAC entity finally receives the data packet with sequence number 0, although the order in which the MAC entity receives the data packets is sequence number 1→2→0, the MAC entity will reorder the data packets to sequence number 0→1→2 based on the reordering mechanism, and deliver the reordered data packets to the RLC entity (i.e., the Radio Link Control entity).

[0006] When communication quality is poor, even if the MAC entity has received packets with sequence number 1 or 2, it cannot deliver these packets to the RLC entity before the MAC entity receives the packet with sequence number 0. Therefore, when the location information of the intelligent logistics vehicle is in the state of packet sequence number 2, the location information of the intelligent logistics vehicle cannot be delivered to the RLC entity and higher-level logical entities in a timely manner. Even in the case of deep channel fading, the MAC entity needs to wait for HARQ (Hybrid Automatic Repeat Request) retransmissions to reach the maximum number before giving up waiting for packets with sequence number 0 and instead using other mechanisms to select a channel with better channel quality to communicate with the sender. The time for waiting for HARQ retransmissions to reach the maximum number is generally several seconds, and the time for reselecting the channel and reconfiguring is also generally several seconds. That is, the location information of the intelligent logistics vehicle will be delayed for several seconds before it can be transmitted to the application layer of the control terminal. This will cause the intelligent logistics vehicle to be unable to receive the control signal of the control terminal in a timely manner within several seconds, and the intelligent logistics vehicle may collide with other intelligent logistics vehicles or with the shelves. Summary of the Invention

[0007] To address the aforementioned problems, this invention provides a control method and control system for intelligent logistics vehicles. This system ensures that key location information of intelligent logistics vehicles can be extracted and reported quickly and efficiently without waiting for potentially lost or delayed data packets. This significantly improves the real-time performance of intelligent logistics vehicle location data processing and system communication efficiency, thereby effectively solving the problem of untimely location reporting.

[0008] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0009] This invention provides a control method for an intelligent logistics vehicle, comprising the following steps: S1, receiving a first data packet sent by the intelligent logistics vehicle; S2, buffering the first data packet in a first receiving window of a first logical entity, wherein the first data packet has a first packet sequence number; S3, the first logical entity determines whether the first data packet includes a specific segment, wherein the specific segment includes the location information of the intelligent logistics vehicle; S4, if the first logical entity determines that the first data packet includes the specific segment, the first logical entity delivers only the first data packet to a location information processing entity, wherein when delivering the first data packet to the location information processing entity, the first receiving window has not yet buffered a second data packet sent by the intelligent logistics vehicle, the second data packet has a second packet sequence number, and the value of the second packet sequence number is less than the value of the first packet sequence number.

[0010] Furthermore, in S4, the location information processing entity splits the first data packet into multiple segments; the location information processing entity identifies a specific segment among the multiple segments, wherein the specific segment has a special segment number; and the location information processing entity delivers only the specific segment to the second logical entity.

[0011] Furthermore, the specific segment is cached in the second receiving window of the second logical entity, wherein the specific segment is cached in a special position in the second receiving window, the special position corresponding to the specific segment sequence number; in response to the specific segment being cached in the special position of the second receiving window, the second logical entity delivers the specific segment to a higher-level logical entity.

[0012] Furthermore, after the location information processing entity delivers the specific segment to the second logical entity, the location information processing entity generates a padding segment, wherein the padding segment has the same size as the specific segment; the location information processing entity reassembles the padding segment with the non-specific segments among the plurality of segments into a third data packet; the third data packet has the same sequence number as the first data packet; and the location information processing entity delivers the third data packet to the first logical entity.

[0013] Furthermore, when the first logical entity delivers the first data packet to the location information processing entity, the first logical entity does not deliver other data packets in the first receiving window to the location information processing entity; when the location information processing entity delivers the specific segment to the second logical entity, the location information processing entity does not deliver non-specific segments among the plurality of segments to the second logical entity.

[0014] Furthermore, in S3, the header of the first data packet includes a first indicator; the first logical entity determines whether the first data packet includes the specific segment; the first logical entity determines whether the header of the first data packet contains the first indicator; if the first logical entity determines that the header of the first data packet contains the first indicator, then the first logical entity determines that the first data packet includes the specific segment.

[0015] Furthermore, the header of the specific segment includes a second indicator; the location information processing entity sequentially reads the header of each of the plurality of segments; and the location information processing entity identifies the segment with the second indicator in the header as the specific segment.

[0016] The present invention provides a control system for an intelligent logistics vehicle, including a control terminal configured to execute the control method described above; the control terminal includes at least a first logical entity, a second logical entity, and a location information processing entity.

[0017] The technical solution provided by this invention has the following beneficial effects:

[0018] By introducing a dedicated location information processing entity into the communication protocol stack and designing a cross-layer, non-sequential data packet and segmented selective processing mechanism, key location information of intelligent logistics vehicles can be extracted and reported preferentially and quickly without waiting for previously lost or delayed data packets. This significantly improves the real-time performance of intelligent logistics vehicle location data processing and system communication efficiency, thereby effectively solving the problem of untimely location reporting. Attached Figure Description

[0019] Figure 1 The diagram shows the state of the receiving window of a MAC entity in the prior art.

[0020] Figure 2 The diagram shown is another state diagram of the receiver window of a MAC entity in the prior art.

[0021] Figure 3 The diagram shown is a schematic of the control system architecture of the intelligent logistics vehicle in Embodiment 1.

[0022] Figure 4 The flowchart shown is a control method for an intelligent logistics vehicle in Embodiment 1.

[0023] Figure 5 The diagram shown is a schematic representation of the relationships between the various logical entities in Example 1.

[0024] Figure 6 The diagram shown is a schematic of the data structure in Example 1.

[0025] Figure 7 The diagram shown is a schematic of the receiving window of the second logical entity in Embodiment 1.

[0026] Figure 8 The diagram shown is a schematic of the data structure containing filled segments in Example 1. Detailed Implementation

[0027] To further illustrate the various embodiments, the present invention provides accompanying drawings. These drawings are part of the disclosure of the present invention and are mainly used to illustrate the embodiments, and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these drawings, those skilled in the art should be able to understand other possible implementations and the advantages of the present invention. Components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0028] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0029] Example 1

[0030] Reference Figures 3 to 8 This embodiment provides a control method for an intelligent logistics vehicle (hereinafter referred to as the control method), wherein, as Figure 3 As shown, multiple intelligent logistics vehicles operate on the roads of a large logistics park. The intelligent logistics vehicles integrate existing communication modules (including baseband chips, antenna arrays, and analog chips that conform to communication standards) and processing modules (including CPUs, memory, and necessary circuits). The intelligent logistics vehicles can communicate with the control terminal. The intelligent logistics vehicles can upload their own speed, position, and running direction information to the control terminal. Based on the speed, position, and running direction information of multiple intelligent logistics vehicles in the logistics park, and combined with the map stored in the control terminal, the control terminal can generate path planning and various control information (such as speed control and running direction) for the intelligent logistics vehicles.

[0031] like Figure 4 As shown, the control method in this embodiment is executed by a control terminal (i.e., a server or a receiving end), and specifically includes the following steps:

[0032] Step S1: The control terminal receives the first data packet sent by the intelligent logistics vehicle.

[0033] Step S2: The first data packet is cached in the first receiving window of the first logical entity (i.e., MAC entity) of the control terminal, wherein the first data packet has a first packet sequence number.

[0034] Step S3: The first logical entity determines whether the first data packet includes a specific segment, wherein the specific segment includes the location information of the intelligent logistics vehicle.

[0035] Step S4: If the first logical entity determines that the first data packet includes a specific segment, then the first logical entity delivers only the first data packet to the location information processing entity. When delivering the first data packet to the location information processing entity, the first receiving window has not yet cached the second data packet sent by the intelligent logistics vehicle. The second data packet has a second packet sequence number, and the value of the second packet sequence number is less than the value of the first packet sequence number.

[0036] In this embodiment, the speed, direction of movement, position coordinates, and relative reference point position of the intelligent logistics vehicle (in indoor areas or areas where satellite signals are blocked, the intelligent logistics vehicle scans via UWB, Bluetooth beacons, or LiDAR and reports the coordinates (X, Y, Z) relative to a known reference point (such as the warehouse entrance, a specific shelf code, or a charging station)) can all be used as the location information of the intelligent logistics vehicle.

[0037] The first logical entity of the control terminal (i.e. the receiving end) first receives the data packets sent by the intelligent logistics vehicle. The first logical entity determines whether the TB is correctly received based on the CRC (i.e., cyclic redundancy check code) of each transmission block TB. If the TB is correctly received, these correctly received TBs are buffered in the receiving window of the first logical entity.

[0038] If all data packets with sequence numbers 0-2 are received correctly, the first logical entity can deliver these data packets to the location information processing entity. If none of the data packets with sequence numbers 0-2 contain a specific segment, the location information processing entity is transparent to the data packets with sequence numbers 0-2. Therefore, the location information processing entity delivers these data packets to the higher-level RLC entity without performing any processing on them.

[0039] like Figure 6 As shown, the first data packet corresponds to a TB of the first logical entity. A TB can be divided into several RLCPDUs (i.e., Radio Link Control Layer Protocol Data Units, the specific number of which depends on the channel quality and the size of the data packet itself).

[0040] like Figure 2 As shown, the sequence number of the first data packet is set to 2, and the sequence number of the second data packet is set to 0.

[0041] The first logical entity's receive window currently has data packets with sequence numbers 1 and 2 cached, but it has not yet correctly received the data packet with sequence number 0. Furthermore, once the first logical entity determines that the data packet with sequence number 2 (i.e., the first data packet) includes a specific segment, it can deliver the data packet containing the specific segment (i.e., the first data packet) to the upper-layer entity without waiting for the correct reception of the data packet with sequence number 0, without reordering the already received data packets, and without delivering the data packet without the specific segment (i.e., the data packet with sequence number 1) to the upper-layer entity. This significantly increases the transmission speed of the intelligent logistics vehicle's location information.

[0042] In summary, by introducing a dedicated location information processing entity into the communication protocol stack and designing a cross-layer, non-sequential data packet and segmented selective processing mechanism, key location information of intelligent logistics vehicles can be extracted and reported preferentially and quickly without waiting for previously lost or delayed data packets. This significantly improves the real-time performance of intelligent logistics vehicle location data processing and system communication efficiency, thereby effectively solving the problem of untimely location reporting.

[0043] Of course, in Figure 5Other logical entities belonging to the prior art are not shown, such as PDCP entity, RRC entity, IP / TCP entity, application layer entity, etc. above RLC entity, which will not be described in detail here.

[0044] In step S3 of the preferred embodiment, after the specific segment is cached in the second receiving window of the second logical entity (i.e., the RLC entity), the specific segment is cached in a specific position within the second receiving window. Of course, in this embodiment, the location information processing entity is a logical entity located between the MAC entity and the RLC entity.

[0045] like Figure 7 As shown, the special position corresponds to the special segment number. In response to a specific segment being cached in the special position of the second receiving window, the second logical entity delivers the specific segment to the higher-level logical entity.

[0046] During operation, the second logical entity receives only one specific segment (i.e., a specific RLCPDU) with a special segment sequence number. Based on the special segment sequence number, the second logical entity caches the specific segment in a special position of its receiving window. This special position of the receiving window is an independent receiving window maintained by the second logical entity (the size of the receiving window is 1). Therefore, as long as the second logical entity caches the specific segment delivered by the lower-level entity in the special position of its receiving window, and the receiving window of the second logical entity can only receive RLCPDUs with the special segment sequence number, the second logical entity will definitely be able to determine that the receiving window has received all RLCPDUs in order and correctly, and deliver the RLCPDU to the higher-level logical entity.

[0047] Since existing communication devices support maintaining multiple receiving windows in the second logical entity according to communication standards, and the size of the receiving window can be arbitrarily set, and the operation mechanism of the receiving window can also be based on existing standards, this embodiment can achieve the individual delivery of specific segments by maintaining only a single receiving window in the second logical entity. Of course, the special segment number can be any value exceeding the upper limit of the receiving window of the second logical entity specified by the standard. For example, according to standard 3GPP TS25.322V5.3.0, the upper limit size of the receiving window of the second logical entity is 4096, then the sequence number range of RLCPDU is 0-4095, and the special segment number can be 5000. Alternatively, the location information of the intelligent logistics vehicle can be ensured to be carried by a single RLCPDU payload through various methods. Alternatively, the amount of information can be reduced by compressing the complexity of the location information (the method of this invention is used only for critical location information; other location information is transmitted according to existing methods). Alternatively, the size of the RLCPDU can be adjusted, thus increasing the payload capacity of a single RLCPDU by increasing its size.

[0048] More preferably, the header of the first data packet includes a first indicator. The first logical entity determines whether the first data packet includes a specific segment, and the first logical entity determines whether the header of the first data packet contains the first indicator. If the first logical entity determines that the header of the first data packet contains the first indicator, then the first logical entity determines that the first data packet includes the specific segment.

[0049] In a specific embodiment, when the value of the field in the header of the TB with packet sequence number 2 that indicates whether the TB includes a specific segment is "1", the first logical entity determines that there is a first indicator in the header of the first data packet; when the value of the aforementioned field is "0", the first logical entity determines that there is no first indicator in the header of the first data packet.

[0050] If the header of a specific segment includes a second indicator, the location information processing entity of the control terminal sequentially reads the header of each segment among multiple segments, and the location information processing entity identifies the segment with the second indicator in the header as the specific segment.

[0051] In step S4 of the preferred embodiment, the location information processing entity splits the first data packet into multiple segments, identifies a specific segment among the multiple segments, wherein the specific segment has a special segment number, and the location information processing entity delivers only the specific segment to the second logical entity of the control terminal.

[0052] When the first logical entity delivers the first data packet to the location information processing entity, the first logical entity does not deliver other data packets in the first receiving window to the location information processing entity.

[0053] When the location information processing entity delivers a specific segment to the second logical entity, the location information processing entity does not deliver non-specific segments from the multiple segments to the second logical entity. That is, the location information processing entity only delivers segments to the second logical entity without delivering segments that are not specific segments to the second logical entity.

[0054] In this specific embodiment, one segment corresponds to one RLCPDU, and the RLCPDU is numbered sequentially without considering a specific segment. For example, if a TB includes 100 RLCPDUs, then the RLCPDUs are numbered 0-99.

[0055] In this embodiment, specific segments are also sequentially numbered. It is assumed that the number of the specific segment is 32, and the second logical entity is also provided with a receiving window (for specific technical details of the receiving window of the RLC entity, please refer to the existing standard 3GPP TS25.322V5.3.0).

[0056] When the location information processing entity delivers a specific segment numbered 32 to the second logical entity, the receiving window of the second logical entity only caches the specific segment numbered 32. The receiving window of the second logical entity lacks segments numbered 0-31. At this time, the second logical entity cannot deliver the specific segment numbered 32 to the upper layer alone. Considering that the functions of the upper-level logical entities are more complex, this embodiment can avoid significantly changing the operation mode of the receiving window of the existing RLC layer entity by using special segment sequence numbers.

[0057] Further preferred, such as Figure 8 As shown, after the location information processing entity delivers the specific segment to the second logical entity, the location information processing entity generates a filler segment, wherein the filler segment has the same size as the specific segment.

[0058] The payload portion of the padding segment can be padded with bits, and the header portion can include a discard indicator that can indicate to the upper-level logic entity that the segment is only used for padding and does not contain valid data, and the upper-level logic entity can discard the padding segment at an appropriate time.

[0059] The sequence number of the padding segment can be the sequence number of the largest RLCPDU in the TB + 1. Assuming that the sequence number of the largest RLCPDU in the TB is 100, the sequence number of the generated padding segment is 101. Then, the location information processing entity reassembles the padding segment with the non-specific segments among the multiple segments into a third data packet. The third data packet has the same sequence number as the first data packet. The location information processing entity delivers the third data packet to the first logical entity.

[0060] After a specific segment from a TB containing a specific segment is delivered to the second logical entity, the TB at the location information processing entity is missing a segment of information. Since the location information processing entity also needs to return the TB to the first logical entity, the first logical entity can reorder all TBs that do not include the specific segment according to the existing standard and deliver them upwards. This ensures that the size of the TB returned by the location information processing entity is consistent with the original TB size. Otherwise, it may cause a logical error in the first logical entity.

[0061] Of course, in other embodiments, the location information processing entity may also be a sub-entity of the MAC entity, a sub-entity of the RLC entity, or an independent entity.

[0062] Example 2

[0063] Embodiment 2 provides a control system for an intelligent logistics vehicle, including a control terminal configured to execute the control method of Embodiment 1. The control terminal includes at least a first logical entity, a second logical entity, and a location information processing entity.

[0064] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A control method for an intelligent logistics vehicle, characterized in that, Includes the following steps: S1 receives the first data packet sent by the intelligent logistics vehicle; S2, the first data packet is cached in the first receiving window of the first logical entity, wherein the first data packet has a first packet sequence number; S3, the first logical entity determines whether the first data packet includes a specific segment, wherein the specific segment includes the location information of the intelligent logistics vehicle; S4, if the first logical entity determines that the first data packet includes the specific segment, then the first logical entity delivers the first data packet only to the location information processing entity. When delivering the first data packet to the location information processing entity, the first receiving window has not yet buffered the second data packet sent by the intelligent logistics vehicle, and the first logical entity does not need to reorder the already received data packets. The second data packet has a second packet sequence number, and the value of the second packet sequence number is less than the value of the first packet sequence number. The first logical entity is a MAC entity, and the second logical entity is an RLC entity. In S4, the location information processing entity splits the first data packet into multiple segments; the location information processing entity identifies a specific segment among the multiple segments, wherein the specific segment has a special segment number; the location information processing entity delivers only the specific segment to the second logical entity. After the location information processing entity delivers the specific segment to the second logical entity, the location information processing entity generates a padding segment, wherein the padding segment has the same size as the specific segment; the location information processing entity reassembles the padding segment with the non-specific segments from the plurality of segments into a third data packet; the third data packet has the same sequence number as the first data packet; the location information processing entity delivers the third data packet to the first logical entity, so that the first logical entity reorders all data packets that do not include the specific segment and delivers them upwards; When the first logical entity delivers the first data packet to the location information processing entity, the first logical entity does not deliver other data packets in the first receiving window to the location information processing entity; when the location information processing entity delivers the specific segment to the second logical entity, the location information processing entity does not deliver the non-specific segments among the plurality of segments to the second logical entity. The specific segment is cached in the second receiving window of the second logical entity, wherein the specific segment is cached in a special position in the second receiving window, the special position corresponding to the specific segment sequence number; in response to the specific segment being cached in the special position of the second receiving window, the second logical entity delivers the specific segment to a higher-level logical entity.

2. The control method for an intelligent logistics vehicle according to claim 1, characterized in that: In S3, the header of the first data packet includes a first indicator; the first logical entity determines whether the first data packet includes the specific segment; the first logical entity determines whether the header of the first data packet contains the first indicator. If the first logical entity determines that the first indicator exists in the header of the first data packet, then the first logical entity determines that the first data packet includes the specific segment.

3. The control method for intelligent logistics vehicles according to claim 1, characterized in that: The header of the specific segment includes a second indicator; the location information processing entity sequentially reads the header of each of the plurality of segments; the location information processing entity identifies the segment with the second indicator in the header as the specific segment.

4. A control system for an intelligent logistics vehicle, characterized in that: The control terminal is configured to execute the control method according to any one of claims 1-3; the control terminal includes at least a first logical entity, a second logical entity, and a location information processing entity.

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