Self-learning positioning structure of storage transfer robot and self-learning positioning method thereof

Abstract

The application provides a self-learning positioning structure and method of a storage and carrying robot, which are high in positioning efficiency and safety. The self-learning positioning structure comprises a control module for controlling the movement of the storage and carrying robot body, a positioning sheet arranged on a main track and corresponding to the position of each track, a first sensor arranged at the bottom of the storage and carrying robot body and used for detecting the positioning sheet, positioning baffles arranged on both sides of each track, a second sensor and a third sensor used for detecting the positioning baffles, and an encoder used for counting. When the first sensor detects the positioning sheet, the control module controls the encoder to start counting. When neither the second sensor nor the third sensor detects the positioning baffles, the control module records the current counting value of the encoder as an offset value. The self-learning positioning method comprises the steps of forward uniform motion, starting forward counting, recording forward offset value, counting zero, continuous forward recording and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of logistics storage and transportation, and particularly to a self-learning positioning structure of a storage and transportation robot and a self-learning positioning method thereof. BACKGROUND

[0002] A logistics storage and transportation robot project is generally composed of a rack, a storage and transportation robot body (four-way vehicle / trolley), a warehouse control system software (WCS), an elevator, a conveying line, a pallet unstacking / stacking machine, etc. The rack includes a pallet storage rack and guide rails (referred to as tracks) required for the storage and transportation robot body to travel. The tracks are divided into X and Y directions, the X direction is referred to as a main track, and the storage and transportation robot body runs at high speed on the main track; the Y direction is referred to as a secondary track, or a rack lane. The secondary track is provided with a pallet support frame for storing pallets. On the main track, an RFID chip and a positioning sheet are installed at the entrance of each secondary track. The storage and transportation robot body is a carrier that travels in the rack to transport pallets from one location to another, thereby completing the pallet moving operation, including: warehousing, de-warehousing, shifting, etc. All points (positions where the secondary track intersects with the main track) that allow the storage and transportation robot body to stop have corresponding coordinate values (X, Y, Z) corresponding thereto. The WCS is a control software that commands all actions of the storage and transportation robot, including traveling, lifting, lowering, etc., according to the requirements of the task. The WCS sends coordinate values (X, Y) to the trolley PLC (or single-chip microcomputer) to make the trolley run to the specified position. A series of actions of the trolley are combined into a pallet transportation task.

[0003] When warehousing, after the storage and transportation robot body obtains a pallet from the entrance (the beginning end of the main track) (the pallet is placed on the top of the storage and transportation robot body), the storage and transportation robot body moves to the entrance of the secondary track (the specified X coordinate) in the X direction of the main track, and then changes direction to run in the Y direction of the secondary track to transport the pallet to the target storage position (the specified Y coordinate). When de-warehousing, after the storage and transportation robot body moves to the entrance of the secondary track (the specified X coordinate) in the X direction of the main track, the storage and transportation robot body changes direction to run in the Y direction, reaches the storage position of the de-warehoused pallet (the specified Y coordinate), lifts the pallet, and then transports the pallet to the specified exit position. When the storage and transportation robot body changes direction from the main track (X direction) to enter the secondary track (Y direction), the storage and transportation robot body needs to be exactly opposite to the Y direction guide rail when the trolley stops in the X direction, and the accuracy of the stopping point is required to be within ±2mm. Therefore, the key and main point of the implementation of the storage and transportation robot project is to ensure the accuracy of the stopping point of the storage and transportation robot body.

[0004] The current positioning method is to install RFID chips or bar codes on the shelves, and the storage handling robot identifies the current coordinate position of the storage handling robot body through an RFID card reader or a bar code scanner for positioning when the trolley is running at high speed. When the storage handling robot body reaches the target position, the storage handling robot body starts to slow down, and when it reaches the target coordinate, it is precisely positioned by sensing the positioning sheet installed on the main track.

[0005] The positioning principle of the current positioning sheet is as follows: the positioning sheet is installed on the main track and located at the center position corresponding to the entrance of the secondary track. On the storage handling robot body, two photoelectric sensors (referred to as positioning photoelectric) are installed, which are located symmetrically on the center line of the trolley and irradiate downward. The distance between the two photoelectric sensors is 96mm, which is just less than the length of the positioning sheet by 4mm (the length of the positioning sheet is 100mm), which means that when the center is aligned, a left-right error of 2mm is allowed. When the two positioning photoelectric sensors of the storage handling robot body sense the positioning sheet, it is considered that the trolley is located at the center position of the secondary track; otherwise, the trolley moves slowly left and right to adjust the position until it is aligned. The current positioning method is to adjust the position of the positioning sheet to ensure the stopping position accuracy of the storage handling robot body, but due to the errors in shelf manufacturing accuracy, installation accuracy and other aspects, the position of each positioning sheet needs to be accurately adjusted. The specific steps are as follows: the trolley slowly enters the secondary track entrance, and the computer program checks whether the two positioning photoelectric sensors sense the positioning sheet, and checks whether the trolley is located on the center line of the secondary track. If it is not on the center line, record the deviation value and move the storage handling robot body away (because the positioning sheet is below the storage handling robot body, the storage handling robot body must be moved away to adjust the position of the positioning sheet), then adjust the position of the positioning sheet left and right, and repeat until the storage handling robot body stops at the center line position of the secondary track.

[0006] Therefore, the traditional positioning method needs to adjust the positioning of each secondary track positioning sheet according to the following steps: measurement → moving away the trolley → adjustment → re-measurement → moving away the trolley again → re-adjustment → …, and the process is repeated until the storage handling robot body stops at the center position of the secondary track. This method takes about 10 minutes on average for each secondary track, which is very tedious and inefficient, and also requires the operator to perform high-altitude operation for a long time (moving away the trolley and adjusting the position of the positioning sheet), which has certain safety hazards. SUMMARY

[0007] The technical problem to be solved by the present application is to provide a self-learning positioning structure and method of a storage handling robot with high positioning efficiency and high safety.

[0008] The purpose of the present application is achieved as follows:

[0009] A self-learning positioning structure of a storage handling robot, comprising a control module for controlling the movement of the storage handling robot body, a positioning sheet arranged on the main track and corresponding to the position of each track, a first sensor arranged on the bottom of the storage handling robot body and used for detecting the positioning sheet, a positioning baffle arranged on both sides of each track, a second sensor and a third sensor arranged on the center-symmetrical position of the storage handling robot body and used for detecting the positioning baffles on both sides of the secondary track respectively, and an encoder electrically connected with the control module and used for counting, wherein the control module is electrically connected with the first sensor and controls the encoder to start counting when the first sensor detects the positioning sheet and controls the encoder to clear the counting when the first sensor leaves the positioning sheet, and the control module is also electrically connected with the second sensor and the third sensor and records the current counting value of the encoder as an offset value when neither the second sensor nor the third sensor detects the positioning baffles.

[0010] The interval distance between the second sensor and the third sensor is equal to the interval distance on both sides of each track.

[0011] Further comprising a label arranged on the main track and recording coordinate values and corresponding to the position of each track, and a card reader arranged on the storage handling robot body and electrically connected with the control module and used for reading the coordinate values of the label.

[0012] The self-learning positioning structure of the storage handling robot as described above, wherein the second sensor and the third sensor are detachably arranged on the top of the storage handling robot body.

[0013] The self-learning positioning structure of the storage handling robot as described above, wherein a magnet is arranged on each of the second sensor and the third sensor.

[0014] The self-learning positioning structure of the storage handling robot as described above, wherein the first sensor, the second sensor and the third sensor are all photoelectric sensors, the label is an RFID chip, and the card reader is an RFID card reader.

[0015] A self-learning positioning method of a storage handling robot using the self-learning positioning structure of the storage handling robot according to any one of the above, comprising the following steps:

[0016] A: forward uniform motion, the control module controls the movement of the storage handling robot body from the beginning end of the main track to the end;

[0017] B: start forward counting, the control module controls the encoder to start counting when the first sensor detects the positioning sheet;

[0018] C: record the positive offset value, when the second sensor and the third sensor do not detect the positioning baffle, the control module records the current count value of the encoder as the positive offset value;

[0019] D: clear the count, when the first sensor leaves the current positioning sheet, the control module controls the encoder to clear the count;

[0020] E: continuously record the positive offset value, repeat steps B to D until the storage handling robot body moves to the end of the main track, so that all the positive offset values corresponding to the secondary tracks are recorded;

[0021] F: reverse uniform motion, the control module controls the storage handling robot body to move from the end of the main track to the beginning of the main track;

[0022] G: start the reverse count, when the first sensor detects the positioning sheet, the control module controls the encoder to start counting;

[0023] H: record the reverse offset value, when the second sensor and the third sensor do not detect the positioning baffle, the control module records the current count value of the encoder as the reverse offset value;

[0024] I: clear the count, when the first sensor leaves the current positioning sheet, the control module controls the encoder to clear the count;

[0025] K: continuously record the reverse offset value, repeat steps G to I until the storage handling robot body moves to the beginning of the main track, so that all the reverse offset values corresponding to the secondary tracks are recorded;

[0026] After the self-learning positioning is completed, the control module records all the coordinate values, positive offset values and reverse offset values corresponding to the secondary tracks; during normal operation, the control module sends a motion instruction to the storage handling robot body and transmits the coordinate values and the positive offset values / reverse offset values to the storage handling robot body, when the storage handling robot body moves to the entrance of the corresponding secondary track, the first sensor detects the corresponding positioning sheet, at this time the encoder starts counting, the storage handling robot body continues to move forward to the position, when the encoder count value is equal to the offset value received by the storage handling robot body, the storage handling robot body stops moving forward, at this time the storage handling robot body is just stopped at the center position of the secondary track, and then the storage handling robot body changes direction from the main track to enter the secondary track.

[0027] The self-learning positioning method of the storage handling robot as described above, when performing the step C and the step H, the card reader reads the coordinate value of the current label, so that the control module records the coordinate value corresponding to the current secondary track.

[0028] The self-learning positioning method of the storage handling robot as described above, when performing the step A and the step F, the control module controls the speed of the uniform motion of the storage handling robot body to be 1 m / s.

[0029] Compared with the prior art, the present application has the following technical features:

[0030] 1. The present application uses the second inductor and the third inductor to determine whether the storage handling robot body is located at the center position of the sub-track, and uses the encoder to calculate the motion offset value of the first inductor relative to the positioning sheet when the storage handling robot body enters the corresponding sub-track entrance and moves to the center position of the sub-track, and the control module records the offset value data of each sub-track, thereby realizing self-learning positioning without human intervention. In normal operation, the offset data recorded by the control module can be directly called to realize rapid positioning of the storage handling robot body.

[0031] 2. The present application is self-learning positioned in the forward direction, and the average positioning learning time consumption of each sub-track is about 6 seconds, which greatly saves the time for adjusting the positioning sheet, thereby improving the efficiency of positioning.

[0032] 3. The present application does not require human intervention, which avoids the safety hazards of high-altitude operation of operators, thereby improving the safety of production.

[0033] 4. If the shelf has changed, the self-learning positioning method of the present application can also easily re-learn positioning. BRIEF DESCRIPTION OF DRAWINGS

[0034] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings, in which:

[0035] Figure 1 is a reference drawing of the use state of the present application (the storage handling robot body enters the entrance of one of the sub-tracks);

[0036] Figure 2 is a front view of Figure 1 ;

[0037] Figure 3 is a reference drawing of the use state of the present application (the storage handling robot body moves to the center position of the corresponding sub-track);

[0038] Figure 4 is a front view of Figure 3 ;

[0039] Figure 5 is a plan view of the shelf;

[0040] Figure 6 is a front view of the shelf;

[0041] Figure 7 is a side view of the shelf. DETAILED DESCRIPTION

[0042] The self-learning positioning structure of the storage and carrying robot comprises a control module (not shown in the figure, which can be a combination of WCS and PLC or a single-chip microcomputer) for controlling the movement of the storage and carrying robot body 10, a positioning sheet 2 arranged on the main track 20 and corresponding to the position of each sub-track 30, a first sensor 3 arranged at the bottom of the storage and carrying robot body 10 and used for detecting the positioning sheet 2, positioning baffles 4 (tray support frames) arranged on both sides of each sub-track 30, a second sensor 5 and a third sensor 6 arranged at the center-symmetrical position of the storage and carrying robot body 10 and used for detecting the positioning baffles 4 on both sides of the sub-track 30 respectively, an encoder electrically connected with the control module and used for counting, the control module is electrically connected with the first sensor 3 and controls the encoder to start counting when the first sensor 3 detects the positioning sheet 2 and controls the encoder to clear the counting when the first sensor 3 leaves the positioning sheet 2, and the control module is also electrically connected with the second sensor 5 and the third sensor 6 and records the current counting value of the encoder as an offset value when neither the second sensor 5 nor the third sensor 6 detects the positioning baffles 4.

[0043] The self-learning positioning structure of the storage and carrying robot described above further comprises a label 8 arranged on the main track 20 and recording coordinate values and corresponding to the position of each sub-track 30, and a card reader 9 arranged on the storage and carrying robot body 10 and electrically connected with the control module and used for reading the coordinate values of the label 8.

[0044] In order to accurately determine whether the storage and carrying robot body 10 is exactly at the center position of the corresponding sub-track 30, the interval distance between the second sensor 5 and the third sensor 6 is equal to the interval distance on both sides of each sub-track 30.

[0045] In order to improve the flexibility of detecting the positioning baffles 4, the second sensor 5 and the third sensor 6 are detachably arranged on the top of the storage and carrying robot body 10. Since the top of the storage and carrying robot body 10 cannot be installed with any device (a tray is needed to be placed to carry goods) during normal operation, the second sensor 5 and the third sensor 6 need to be detached after the self-learning positioning is completed.

[0046] In order to facilitate disassembly and assembly, a magnet is arranged on each of the second sensor 5 and the third sensor 6. During the self-learning positioning, the adsorption of the magnet can ensure that the second sensor 5 and the third sensor 6 are firmly fixed on the top of the storage and carrying robot body 10, and after the self-learning positioning is completed, the second sensor 5 and the third sensor 6 can be easily detached.

[0047] Preferably, the first sensor 3, the second sensor 5 and the third sensor 6 are photoelectric sensors, the tag 8 is an RFID chip, and the card reader 9 is an RFID card reader.

[0048] The self-learning positioning method of the storage handling robot comprises the following steps: A: forward uniform motion, the control module controls the storage handling robot body 10 to move from the beginning of the main track 20 to the end; B: start forward counting, when the first sensor 3 detects the positioning sheet 2, the control module controls the encoder to start counting; C: record the forward offset value, when the second sensor 5 and the third sensor 6 do not detect the positioning baffle 4, the control module records the current counting value of the encoder as the forward offset value; D: count zero, when the first sensor 3 leaves the current positioning sheet 2, the control module controls the encoder to count zero; E: continue forward recording, repeat steps B to D until the storage handling robot body 10 moves to the end of the main track 20, so that all the forward offset values corresponding to the secondary track 30 are recorded.

[0049] The self-learning positioning method of the storage handling robot described above further comprises the following steps: F: reverse uniform motion, the control module controls the storage handling robot body 10 to move from the end of the main track 20 to the beginning; G: start reverse counting, when the first sensor 3 detects the positioning sheet 2, the control module controls the encoder to start counting; H: record the reverse offset value, when the second sensor 5 and the third sensor 6 do not detect the positioning baffle 4, the control module records the current counting value of the encoder as the reverse offset value; I: count zero, when the first sensor 3 leaves the current positioning sheet 2, the control module controls the encoder to count zero; K: continue reverse recording, repeat steps G to I until the storage handling robot body 10 moves to the beginning of the main track 20, so that all the reverse offset values corresponding to the secondary track 30 are recorded.

[0050] Preferably, when steps C and H are performed, the card reader 9 reads the coordinate value of the current tag 8, so that the control module records the coordinate value corresponding to the current secondary track 30.

[0051] Preferably, when steps A and F are performed, the control module controls the storage handling robot body 10 to move at a speed of 1 m / s.

[0052] After the self-learning positioning is completed, the control module records all the coordinate values, positive offset values and negative offset values corresponding to the sub-track 20. During normal operation, the control module sends a movement instruction to the storage handling robot body 10 and transmits the coordinate values and positive offset values / negative offset values to the storage handling robot body 10. When the storage handling robot body 10 moves to the entrance of the corresponding sub-track 30, the first sensor 3 detects the corresponding positioning sheet 2. At this time, the encoder starts counting, and the storage handling robot body 10 continues to move forward to search for the position. When the encoder count value is equal to the offset value received by the storage handling robot body 10, the storage handling robot body 10 stops moving forward. At this time, the storage handling robot body 10 is just stopped at the center position of the sub-track 30, and then the storage handling robot body 10 can change direction from the main track 20 (X direction) to the sub-track 30 (Y direction).

Claims

1. A self-learning positioning structure of a storage handling robot, characterized in that The control module controls the action of the storage handling robot body (10), the positioning sheet (2) is arranged on the main track (20) and corresponds to the position of each sub-track (30), the first sensor (3) is arranged on the bottom of the storage handling robot body (10) and is used for detecting the positioning sheet (2), the positioning baffle (4) is arranged on both sides of each sub-track (30), the second sensor (5) and the third sensor (6) are arranged on the center-symmetric position of the storage handling robot body (10) and are used for detecting the positioning baffle (4) on both sides of the sub-track (30) respectively, the encoder is electrically connected with the control module and is used for counting, the control module is electrically connected with the first sensor (3) and controls the encoder to start counting when the first sensor (3) detects the positioning sheet (2) and controls the encoder to clear the count when the first sensor (3) leaves the positioning sheet (2), the control module is also electrically connected with the second sensor (5) and the third sensor (6) and records the current count value of the encoder as an offset value when the second sensor (5) and the third sensor (6) do not detect the positioning baffle (4) at the same time. The interval distance between the second sensor (5) and the third sensor (6) is equal to the interval distance on both sides of each sub-track (30). The label (8) is arranged on the main track (20) and records the coordinate value and the position corresponds to the position of each sub-track (30), and the card reader (9) is arranged on the storage handling robot body (10) and is electrically connected with the control module and is used for reading the coordinate value of the label (8).

2. The self-teaching positioning structure of a storage and transfer robot according to claim 1, characterized in that The second sensor (5) and the third sensor (6) are detachably arranged on the top of the storage handling robot body (10).

3. The self-teaching positioning structure of a storage handling robot according to claim 1, characterized in that Magnets are arranged on the second sensor (5) and the third sensor (6).

4. The self-teaching positioning structure of a storage handling robot according to claim 1, characterized in that The first sensor (3), the second sensor (5) and the third sensor (6) are all photoelectric sensors, the label (8) is an RFID chip, and the card reader (9) is an RFID card reader.

5. A self-localization method of a storage handling robot employing a self-localization structure of a storage handling robot according to any one of claims 1-4, characterized by The method comprises the following steps: A: forward uniform motion, the control module controls the storage handling robot body (10) to move from the beginning end of the main track (20) to the end; B: start counting forward, when the first sensor (3) detects the positioning sheet (2), the control module controls the encoder to start counting; C: record the forward offset value, when the second sensor (5) and the third sensor (6) do not detect the positioning baffle (4) at the same time, the control module records the current count value of the encoder as the forward offset value; D: clear the count, when the first sensor (3) leaves the current positioning sheet (2), the control module controls the encoder to clear the count; E: continue to record forward, repeat steps B to D until the storage handling robot body (10) moves to the end of the main track (20), so that all the corresponding forward offset values of the sub-track (30) are recorded. F: Reverse uniform motion, the control module controls the storage handling robot body (10) to move from the end of the main track (20) to the beginning; G: Start reverse counting, when the first sensor (3) detects the positioning sheet (2), the control module controls the encoder to start counting; H: Record the reverse offset value, when the second sensor (5) and the third sensor (6) do not detect the positioning baffle (4), the control module records the current counting value of the encoder as the reverse offset value; I: Counting zero, when the first sensor (3) leaves the current positioning sheet (2), the control module controls the encoder to count zero; K: Continue reverse recording, repeat steps G to I until the storage handling robot body (10) moves to the beginning of the main track (20), so that all reverse offset values corresponding to the secondary track (30) are recorded; After the self-learning positioning is completed, the control module records all coordinate values, forward offset values and reverse offset values corresponding to the secondary track; during normal operation, the control module sends a motion instruction to the storage handling robot body and transmits the coordinate values and forward offset values / reverse offset values to the storage handling robot body, when the storage handling robot body moves to the entrance of the corresponding secondary track, the first sensor detects the corresponding positioning sheet, at this time the encoder starts counting, the storage handling robot body continues to move forward, when the encoder counting value is equal to the offset value received by the storage handling robot body, the storage handling robot body stops moving forward, at this time the storage handling robot body is just stopped at the center position of the secondary track, and then the storage handling robot body changes direction from the main track to enter the secondary track.

6. The self-learning positioning method of a storage handling robot according to claim 5, characterized in that When performing the step C and the step H, the card reader (9) reads the coordinate value of the current label (8), so that the control module records the coordinate value corresponding to the current secondary track (30).

7. A self-learning positioning method of a storage handling robot according to claim 5 or 6, characterized in that When performing the step A and the step F, the control module controls the speed of the uniform motion of the storage handling robot body (10) to be 1 m / s.

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