Multi-sensor fusion high-precision positioning four-way shuttle vehicle

Abstract

The application relates to the technical field of intelligent warehouse equipment positioning, and discloses a high-precision positioning four-way shuttle vehicle with multi-sensor fusion. The high-precision positioning four-way shuttle vehicle with multi-sensor fusion comprises a vehicle body, a control system and a positioning system. The positioning system comprises a positioning mark group composed of a two-dimensional code or one-dimensional code mark matched with a color mark, a code reader and a color mark sensor installed at the bottom of the vehicle body, a motor encoder installed on a driving motor, an inertial measurement unit installed on the vehicle body, and a controller electrically connected with the above components. The positioning mark group comprises a correction group, a position group and a protection group. The controller comprises a coordinate establishing module, a mobile positioning module, a deviation correction module, an end positioning module, an abnormal self-recovery module and a safety protection module. The application has the functions of automatic correction of skidding, encoder failure protection, self-recovery capability and track safety protection through multi-sensor fusion positioning, and is suitable for an automatic stereoscopic warehouse system.

Description

Technical Field

[0001] This invention relates to the field of intelligent warehousing equipment positioning technology, specifically a high-precision positioning four-way shuttle vehicle with multi-sensor fusion. Background Technology

[0002] Four-way shuttles are intelligent warehousing devices capable of moving flexibly in four directions (front, back, left, and right) along rack tracks, and are widely used in automated storage and retrieval systems (AS / RS). With the rapid development of intelligent logistics and intelligent manufacturing, the requirements for the automation level, operational efficiency, and safety of warehousing systems are becoming increasingly stringent. As the core handling equipment in a warehousing system, the positioning accuracy of the four-way shuttle directly affects the accuracy of goods storage and retrieval and the overall operational efficiency of the warehousing system.

[0003] Currently, the positioning technology of four-way shuttles mainly faces the following challenges: traditional positioning methods have limited accuracy, making it difficult to meet the demand for precise positioning in high-density storage scenarios; the positioning process is easily affected by environmental interference, leading to the accumulation of positioning errors; abnormal situations such as wheel slippage can cause positioning failure, and there is a lack of effective correction mechanisms; there is a lack of effective self-recovery mechanisms, requiring manual intervention when positioning is abnormal; and there are insufficient safety protection measures, posing a risk of derailment.

[0004] In existing technologies, four-way shuttle positioning technology is mainly implemented in the following ways: 1) Positioning method based on a single encoder: The travel distance is recorded by the servo motor encoder, and the current position is calculated by combining the initial position. The drawback of this method is that the encoder error accumulates with the travel distance, and the positioning accuracy drops significantly after long-term operation; wheel slippage or mechanical backlash can cause positioning failure, and it cannot be automatically corrected.

[0005] 2) RFID tag-based positioning method: RFID tags are deployed at key locations on the track, and the shuttle obtains its location information by reading the tags. The drawbacks of this method are: it requires a large number of RFID tags, resulting in high costs; there are blind spots in tag reading, and positioning accuracy is limited by tag density; it has weak anti-interference capabilities, and metallic environments can affect reading performance.

[0006] 3) Laser-based positioning method: This method uses a laser sensor to measure the distance to a fixed reference object for positioning. The drawbacks of this method are: it is highly sensitive to environmental conditions; dust and smoke can affect measurement accuracy; the equipment is expensive and maintenance is complex.

[0007] 4) Visual recognition-based localization method: This method locates objects by recognizing preset markers using a camera. The drawbacks of this method are: it is sensitive to lighting conditions, and environmental changes can affect the recognition results; it also involves high computational demands, making real-time performance difficult to guarantee.

[0008] The above methods all lack effective slippage correction mechanisms and self-recovery capabilities, and have insufficient safety protection measures. Therefore, a high-precision positioning four-way shuttle vehicle with multi-sensor fusion is proposed to solve the above problems. Summary of the Invention

[0009] Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a high-precision positioning four-way shuttle vehicle with multi-sensor fusion, which has advantages such as high positioning accuracy, fast positioning, automatic slip correction, high stability, encoder failure protection, self-recovery capability, high safety and no error accumulation. It solves the problems of low accuracy, error accumulation, lack of slip correction mechanism and insufficient safety protection in existing four-way shuttle vehicle positioning technologies.

[0010] (II) Technical Solution The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A high-precision positioning four-way shuttle vehicle with multi-sensor fusion, comprising a vehicle body and a control system mounted on the vehicle body, wherein the four-way shuttle vehicle is further provided with a positioning system, the positioning system comprising: The positioning mark set consists of a pair of QR code or barcode labels and color code labels set on the shelf rails. Each storage location is equipped with two single rails. The QR code or barcode label is affixed to the inside of the left rail, and the color code label corresponding to the QR code or barcode label is affixed to the inside of the right rail, forming a paired positioning mark set. The barcode reader and color mark sensor are installed at the bottom of the vehicle body, including two pairs of barcode readers and color mark sensors corresponding to the front and rear driving directions respectively. The barcode reader is used to read the information of the QR code or one-dimensional barcode mark, and the color mark sensor is used to detect the position of the color mark mark. Motor encoders are installed on the drive motor of the vehicle body to record the driving distance and speed in real time; An inertial measurement unit, mounted on the vehicle body, is used to measure the acceleration and angular velocity of the four-way shuttle in real time. The controller is electrically connected to the barcode reader, color mark sensor, motor encoder, and inertial measurement unit, respectively, and is used to perform fusion positioning based on the reading results of the barcode reader and color mark sensor, the travel distance and speed recorded by the motor encoder, and the acceleration and angular velocity measured by the inertial measurement unit; The positioning marker group includes a correction group, a position group, and a protection group. The correction group is used to correct the physical position deviation between the current four-way shuttle and the target endpoint. The QR code or one-dimensional code of the correction group contains a positive correction code or a negative correction code. The position group is used to provide the absolute coordinates of the current four-way shuttle in the warehouse. The protection group is set at the track endpoints and key positions to prevent the four-way shuttle from running off the track. The controller includes a coordinate establishment module, a motion positioning module, a deviation correction module, a destination positioning module, an anomaly self-recovery module, and a safety protection module. The coordinate establishment module is used to establish a physical coordinate system with any corner point in the warehouse as the three-dimensional coordinate origin. The motion positioning module is used to calculate the absolute coordinates of the four-way shuttle in the warehouse based on the coordinate information read by the barcode reader and the distance calculated by the motor encoder during the movement of the four-way shuttle. The deviation correction module is used to perform smooth correction by calculating the difference between the correction group and the position group when both the correction group and the position group are valid. The destination positioning module is used to obtain the distance to the destination from the data of the correction group and perform final correction during destination positioning, and to perform final positioning in conjunction with the position group. The anomaly self-recovery module is used to control the four-way shuttle to automatically search for the positioning marker and reset the position when a positioning anomaly is detected. The safety protection module is used to control the braking of the four-way shuttle based on the signal from the protection group. The barcode reader is a 60-frame barcode reader with a motion tolerance of 3.5 m / s. The color mark sensor has a detection distance of 250 mm and uses NPN output. The motor encoder is a 13-bit incremental magnetic encoder. The inertial measurement unit is a three-axis 180-degree angle and acceleration detection unit. The positioning system has a positioning accuracy of less than ±2mm and a repeatability of less than ±1mm. The barcode reader is a Newland NLS-FM430EX barcode reader, and the color mark sensor (500) is a SICK KTM-LN55182P color mark sensor.

[0011] The beneficial effects of this invention are: 1) This high-precision positioning four-way shuttle vehicle with multi-sensor fusion uses a positioning mark group composed of QR code or one-dimensional barcode mark and color mark mark, combined with multi-sensor fusion positioning of barcode reader, color mark sensor, motor encoder and inertial measurement unit. The positioning accuracy is less than ±2mm and the repeatability is less than ±1mm. It has the advantage of high positioning accuracy and solves the problem of low positioning accuracy in the existing technology. 2) This high-precision positioning four-way shuttle vehicle with multi-sensor fusion uses a 60-frame barcode reader in conjunction with a motor encoder for continuous positioning. The QR code or 1D barcode recognition speed is fast, which improves the positioning speed and system operating efficiency, and has the advantage of rapid positioning. 3) This high-precision positioning four-way shuttle with multi-sensor fusion, through the cooperation of the correction group and the position group, when the four-way shuttle slips and causes position deviation, the deviation correction module performs smooth correction by calculating the difference between the correction group and the position group when both the correction group and the position group are valid. This achieves automatic correction of slip deviation and has the advantage of automatic slip correction. 4) This high-precision positioning four-way shuttle vehicle with multi-sensor fusion achieves its function through different code groups of correction group, position group and protection group, which greatly reduces the stability drop caused by false triggering and other reasons, and has the advantage of high stability. 5) This high-precision positioning four-way shuttle, which integrates multiple sensors, can still determine and process the relative position of the four-way shuttle to the destination even when the motor encoder data fails abnormally, thanks to the position group and correction group working together. It has the advantage of encoder failure protection. 6) This high-precision positioning four-way shuttle vehicle, which integrates multiple sensors, can automatically search for positioning markers and reset its position when an abnormality is detected by the abnormality self-recovery module, thus restoring normal operation without manual intervention and possessing the advantage of self-recovery capability. 7) This high-precision positioning four-way shuttle car with multi-sensor fusion has protection groups set at the track endpoints and key positions. The safety protection module controls the braking of the four-way shuttle car according to the signals of the protection groups, ensuring that the shuttle car will not run off the track when it is interfered with or the positioning fails, thus having the advantage of high safety. 8) This high-precision positioning four-way shuttle car, which integrates multiple sensors, provides the absolute coordinates of the current four-way shuttle car in the warehouse through the position group. The absolute position is calibrated regularly to eliminate the cumulative error of the motor encoder, and has the advantage of not accumulating errors.

[0012] Based on the above technical solution, the present invention can be further improved as follows.

[0013] Furthermore, a high-precision positioning method for a four-way shuttle vehicle using multi-sensor fusion is proposed, comprising the following steps: S1: Coordinate system establishment steps: Specify any corner point in the warehouse as the origin of the three-dimensional coordinate system to establish a physical coordinate system; S2: Mobile positioning steps: During the movement of the four-way shuttle, the coordinate information obtained by reading the QR code or one-dimensional barcode mark by the barcode reader and the distance calculated by the motor encoder are used to calculate the absolute coordinates of the four-way shuttle in the warehouse. S3: Slippage Deviation Correction Step: When the four-way shuttle causes a positional deviation due to slippage, if both the correction group and the position group are valid, the difference between the correction group and the position group is calculated for smoothing correction. S4: Final Destination Precision Positioning Steps: During endpoint positioning, the distance to the endpoint is obtained again using data from the correction group for final correction, and deceleration is used in conjunction with the position group for final positioning; and S5: Abnormal self-recovery steps: When a positioning abnormality is detected, the system automatically searches for positioning markers to reset the location and restore normal operation.

[0014] S3 slippage deviation correction step smoothing correction is performed when both the correction group and the position group are valid; Safety protection steps: When the four-way shuttle approaches the end point of the track, the safety protection mechanism is triggered by the protection group to control the four-way shuttle to brake and stop. In the S3 slippage correction step, the smoothing correction adopts a progressive correction method, so that the four-way shuttle gradually returns to the target path.

[0015] The beneficial effects of adopting the above-mentioned further solutions are: 1) The high-precision positioning method of the four-way shuttle car using multi-sensor fusion establishes a physical coordinate system by taking any corner point of the warehouse as the origin of the three-dimensional coordinate system through the S1 coordinate system establishment step, which provides a unified absolute coordinate reference for the four-way shuttle car, facilitating subsequent positioning calculations. 2) The high-precision positioning method of the four-way shuttle car using multi-sensor fusion obtains coordinate information by reading the QR code or 1D barcode mark through the S2 mobile positioning step, and determines the absolute coordinates of the four-way shuttle car by combining the distance calculated by the motor encoder. This achieves fast and continuous positioning and has the advantage of high positioning efficiency. 3) The positioning method of the high-precision positioning four-way shuttle car by multi-sensor fusion, through the S3 slip deviation correction step, when both the correction group and the position group are valid, adopts a progressive correction method to make the four-way shuttle car gradually return to the target path, realizes the smooth correction of slip deviation, avoids sudden positioning, and ensures the stability of shuttle car operation and positioning accuracy. 4) The positioning method of this high-precision positioning four-way shuttle car using multi-sensor fusion, through the S4 endpoint precise positioning step, uses the correction group to obtain the distance to the endpoint again for final correction, and decelerates in coordination with the position group to perform final positioning, thus achieving high-precision positioning of the endpoint and ensuring the accuracy of goods storage and retrieval. 5) The positioning method of this high-precision positioning four-way shuttle car using multi-sensor fusion automatically searches for positioning markers to reset the position and restore normal operation when a positioning anomaly is detected through the S5 anomaly self-recovery step, without the need for manual intervention, reducing equipment downtime and improving the automation level and operating efficiency of the warehousing system. 6) The high-precision positioning method of the four-way shuttle car using multi-sensor fusion has a safety protection step. When the four-way shuttle car approaches the end of the track, the protection group triggers the safety protection mechanism to control the braking and stop, which effectively prevents the shuttle car from running off the track and ensures the safety of equipment and goods. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the code group layout method of the present invention; Figure 2 This is a layout diagram of the internal sensors of the four-way vehicle according to the present invention; Figure 3 This is a schematic diagram illustrating the establishment of the coordinate system in this invention; Figure 4 This is a flowchart illustrating the positioning and correction process of the present invention.

[0017] In the diagram: 100, QR code or 1D barcode mark; 200, color mark mark; 300, positioning mark group; 310, correction group; 320, position group; 330, protection group; 400, code reader; 500, color mark sensor; 600, motor encoder; 700, inertial measurement unit; 800, controller; 810, coordinate establishment module; 820, motion positioning module; 830, deviation correction module; 840, endpoint positioning module; 850, anomaly self-recovery module; 860, safety protection module. Detailed Implementation

[0018] 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.

[0019] Example 1, by Figure 1-4 This invention provides a high-precision positioning four-way shuttle vehicle using multi-sensor fusion. The invention includes a vehicle body and a control system mounted on the vehicle body. The four-way shuttle vehicle also includes a positioning system, which comprises: The positioning mark group 300 consists of a pair of QR code or one-dimensional barcode mark 100 and color mark mark 200 set on the shelf track. Each storage location is equipped with two single tracks. The QR code or one-dimensional barcode mark 100 is affixed to the inside of the left track, and the color mark mark 200 corresponding to the QR code or one-dimensional barcode mark 100 is affixed to the inside of the right track, forming a paired positioning mark group 300. The barcode reader 400 and the color mark sensor 500 are installed on the bottom of the vehicle body. The barcode reader 400 and the color mark sensor 500 are respectively corresponding to the front and rear driving directions. The barcode reader 400 is used to read the information of the QR code or one-dimensional barcode mark 100, and the color mark sensor 500 is used to detect the position of the color mark mark 200. The 600 motor encoder is installed on the drive motor of the vehicle body to record the driving distance and speed in real time. The inertial measurement unit 700 is mounted on the vehicle body and is used to measure the acceleration and angular velocity of the four-way shuttle in real time. The controller 800 is electrically connected to the barcode reader 400, the color mark sensor 500, the motor encoder 600, and the inertial measurement unit 700, respectively, and is used to perform fusion positioning based on the reading results of the barcode reader 400 and the color mark sensor 500, the driving distance and speed recorded by the motor encoder 600, and the acceleration and angular velocity measured by the inertial measurement unit 700. The positioning marker group 300 includes a correction group 310, a position group 320, and a protection group 330. The correction group 310 is used to correct the physical position deviation between the current four-way shuttle and the target endpoint. The QR code or one-dimensional code marker 100 of the correction group 310 contains a positive correction code or a negative correction code. The position group 320 is used to provide the absolute coordinates of the current four-way shuttle in the warehouse. The protection group 330 is set at the track endpoints and key positions to prevent the four-way shuttle from running off the track. The controller 800 includes a coordinate establishment module 810, a motion positioning module 820, a deviation correction module 830, a destination positioning module 840, an anomaly self-recovery module 850, and a safety protection module 860. The coordinate establishment module 810 is used to establish a physical coordinate system with any corner point in the warehouse as the origin of the three-dimensional coordinate system. The motion positioning module 820 is used to calculate the absolute coordinates of the four-way shuttle in the warehouse based on the coordinate information read by the code reader 400 and the distance calculated by the motor encoder 600 during the movement of the four-way shuttle. The deviation correction module 830 is used for… When both correction group 310 and position group 320 are valid, smooth correction is performed by calculating the difference between correction group 310 and position group 320. The endpoint positioning module 840 is used to obtain the distance to the endpoint from the data of correction group 310 and perform final correction when positioning the endpoint, and cooperate with position group 320 to perform final positioning. The abnormal self-recovery module 850 is used to control the four-way shuttle to automatically search for positioning markers and reset the position when a positioning abnormality is detected. The safety protection module 860 is used to control the braking of the four-way shuttle according to the signal of protection group 330. The code reader 400 is a 60-frame code reader with a motion tolerance of 3.5m / s. The color mark sensor 500 has a detection distance of 250mm and adopts NPN output. The motor encoder 600 is a 13-bit incremental magnetic encoder. The inertial measurement unit 700 is a three-axis 180-degree angle and acceleration detection unit. The positioning system has a positioning accuracy of less than ±2mm and a repeatability of less than ±1mm. The barcode reader 400 uses the Newland NLS-FM430EX barcode reader, and the color mark sensor 500 uses the SICK KTM-LN55182P color mark sensor.

[0020] Example 2, based on Example 1, proposes a high-precision positioning method for a four-way shuttle vehicle using multi-sensor fusion, comprising the following steps: S1: Coordinate system establishment steps: Specify any corner point in the warehouse as the origin of the three-dimensional coordinate system to establish a physical coordinate system; S2: Mobile positioning steps: During the movement of the four-way shuttle, the coordinate information obtained by reading the QR code or one-dimensional code mark by the code reader 400 and the distance calculated by the motor encoder 600 are used to calculate the absolute coordinates of the four-way shuttle in the warehouse. S3: Slippage deviation correction step: When the four-way shuttle causes a positional deviation due to slippage, if both the correction group 310 and the position group 320 are valid, the difference is calculated by the correction group 310 and the position group 320 for smooth correction. S4: Final destination positioning steps: During final destination positioning, the distance to the destination is obtained again using data from correction group 310 for final correction, and deceleration is used in conjunction with position group 320 for final positioning; and S5: Abnormal self-recovery steps: When a positioning abnormality is detected, the system automatically searches for positioning markers to reset the location and restore normal operation.

[0021] S3 slippage deviation correction step smoothing correction is performed when both correction group 310 and position group 320 are valid; Safety protection steps: When the four-way shuttle approaches the end point of the track, the safety protection mechanism is triggered by the protection group 330 to control the four-way shuttle to brake and stop. In the S3 slippage correction step, the smoothing correction adopts a progressive correction method, so that the four-way shuttle gradually returns to the target path.

[0022] Working principle: Implementation steps for the first innovation point: Step 1: As the four-way shuttle travels along the shelf track, the barcode reader 400 and color mark sensor 500 installed at the bottom of the vehicle body read the positioning mark group 300 on the inner side of the track in real time. Specifically, the barcode reader 400 reads the QR code or one-dimensional barcode mark 100 on the inner side of the left track and obtains the encoded information stored therein. The color mark sensor 500 simultaneously detects the color mark mark 200 on the inner side of the right track and obtains the color mark position signal. The two pairs of barcode readers 400 and color mark sensors 500, which correspond to the front and rear travel directions respectively, ensure that the shuttle can effectively read the positioning marks when traveling in both directions. Step 2: The controller 800 receives the reading results from the code reader 400 and the color mark sensor 500, and simultaneously acquires the real-time travel distance and speed data recorded by the motor encoder 600 and the real-time acceleration and angular velocity data measured by the inertial measurement unit 700. The controller 800 fuses the above multi-source sensor data. When the code reader 400 reads the position group 320, it directly acquires the absolute coordinates of the four-way shuttle in the warehouse. In the interval where the position group 320 is not read, the most recently read absolute coordinates are used as the reference, and dead reckoning is performed by combining the travel distance data from the motor encoder 600 and the acceleration and angular velocity data from the inertial measurement unit 700 to achieve continuous positioning. Step 3: The controller 800 uses the above multi-sensor fusion positioning algorithm to make the positioning accuracy of the positioning system less than ±2mm and the repeatability less than ±1mm. It then outputs the calculated real-time location information of the four-way shuttle to the control system for navigation control and cargo storage and retrieval operations.

[0023] Implementation steps for the second innovation point: Step 1: First, the coordinate establishment module 810 establishes a physical coordinate system (WCS) with any corner point in the warehouse as the three-dimensional coordinate origin. After the four-way shuttle is started, the mobile positioning module 820 calculates the absolute coordinates of the four-way shuttle in the warehouse based on the coordinate information obtained by the barcode reader 400 reading the QR code or one-dimensional barcode mark 100 and the distance calculated by the motor encoder 600, so as to realize real-time positioning and tracking during the movement process. Step 2: When the four-way shuttle causes a positional deviation due to wheel slippage, the deviation correction module 830 monitors the reading status of the correction group 310 and the position group 320 in real time. When both the correction group 310 and the position group 320 are valid, the deviation correction module 830 calculates the current positional deviation amount through the difference between the correction group 310 and the position group 320. It adopts a progressive correction method to make the four-way shuttle gradually return to the target path, realize the smooth correction of slippage deviation, and avoid sudden positioning changes. Step 3: When the four-way shuttle approaches the target endpoint, the endpoint positioning module 840 obtains the distance to the endpoint again through the data of the correction group 310, performs final correction, and controls the shuttle to decelerate in coordination with the position group 320 to perform final positioning, achieving high-precision positioning of the endpoint. Throughout the operation, the safety protection module 860 monitors the signal of the protection group 330 in real time. When the four-way shuttle approaches the track endpoint, the protection group 330 triggers the safety protection mechanism, and the safety protection module 860 controls the four-way shuttle to brake and stop to prevent it from running off the track. When the abnormal self-recovery module 850 detects a positioning abnormality, it automatically controls the four-way shuttle to search for positioning markers to reset its position and restore normal operation.

[0024] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0025] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-precision positioning four-way shuttle vehicle with multi-sensor fusion, comprising a vehicle body and a control system mounted on the vehicle body, characterized in that, The four-way shuttle is also equipped with a positioning system, which includes: The positioning mark group (300) consists of a pair of QR code or one-dimensional barcode mark (100) and color mark mark (200) set on the shelf track. Each storage location is equipped with two single tracks. The QR code or one-dimensional barcode mark (100) is affixed to the inside of the left track, and the color mark mark (200) corresponding to the QR code or one-dimensional barcode mark (100) is affixed to the inside of the right track, forming a paired positioning mark group (300). The barcode reader (400) and color mark sensor (500) are installed on the bottom of the vehicle body, including two pairs of barcode readers (400) and color mark sensors (500) corresponding to the front and rear driving directions respectively. The barcode reader (400) is used to read the information of the QR code or one-dimensional barcode mark (100), and the color mark sensor (500) is used to detect the position of the color mark mark (200). The motor encoder (600) is installed on the drive motor of the vehicle body to record the driving distance and speed in real time; An inertial measurement unit (700) is mounted on the vehicle body and is used to measure the acceleration and angular velocity of the four-way shuttle in real time. The controller (800) is electrically connected to the barcode reader (400), color mark sensor (500), motor encoder (600) and inertial measurement unit (700) respectively, and is used to perform fusion positioning based on the reading results of the barcode reader (400) and color mark sensor (500), the driving distance and speed recorded by the motor encoder (600) and the acceleration and angular velocity measured by the inertial measurement unit (700).

2. The high-precision positioning four-way shuttle vehicle with multi-sensor fusion according to claim 1, characterized in that: The positioning marker group (300) includes a correction group (310), a position group (320), and a protection group (330). The correction group (310) is used to correct the physical position deviation between the current four-way shuttle and the target endpoint. The QR code or one-dimensional barcode marker (100) of the correction group (310) contains a positive correction code or a negative correction code. The position group (320) is used to provide the absolute coordinates of the current four-way shuttle in the warehouse. The protection group (330) is set at the track endpoints and key positions to prevent the four-way shuttle from running off the track.

3. The high-precision positioning four-way shuttle vehicle with multi-sensor fusion according to claim 2, characterized in that: The controller (800) includes a coordinate establishment module (810), a motion positioning module (820), a deviation correction module (830), a destination positioning module (840), an anomaly self-recovery module (850), and a safety protection module (860). The coordinate establishment module (810) is used to establish a physical coordinate system with any corner point in the warehouse as the origin of the three-dimensional coordinate system. The motion positioning module (820) is used to calculate the absolute coordinates of the four-way shuttle in the warehouse based on the coordinate information read by the barcode reader (400) and the distance calculated by the motor encoder (600) during the movement of the four-way shuttle. The deviation correction module (830) is used to calculate the absolute coordinates of the four-way shuttle in the warehouse based on the coordinate information read by the barcode reader (400) and the distance calculated by the motor encoder (600). The system is used to perform smooth correction by calculating the difference between the correction group (310) and the position group (320) when both the correction group (310) and the position group (320) are valid. The endpoint positioning module (840) is used to obtain the distance to the endpoint by the data of the correction group (310) and perform final correction when positioning the endpoint, and cooperate with the position group (320) to perform final positioning. The abnormal self-recovery module (850) is used to control the four-way shuttle to automatically search for positioning markers and reset the position when a positioning abnormality is detected. The safety protection module (860) is used to control the braking of the four-way shuttle according to the signal of the protection group (330).

4. The high-precision positioning four-way shuttle vehicle with multi-sensor fusion according to claim 1, characterized in that: The barcode reader (400) is a 60-frame barcode reader with a motion tolerance of 3.5 m / s. The color mark sensor (500) has a detection distance of 250 mm and adopts NPN output. The motor encoder (600) is a 13-bit incremental magnetic encoder. The inertial measurement unit (700) is a three-axis 180-degree angle and acceleration detection unit.

5. A high-precision positioning four-way shuttle vehicle with multi-sensor fusion according to claim 1, characterized in that: The positioning system has a positioning accuracy of less than ±2mm and a repeatability of less than ±1mm.

6. The four-way shuttle according to any one of claims 1 to 5, characterized in that, The barcode reader (400) is a Newland NLS-FM430EX barcode reader, and the color mark sensor (500) is a SICK KTM-LN55182P color mark sensor.

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