Initial setting method for unmanned forklift

Abstract

The present application provides an initial setting method of unmanned forklift capable of inhibiting the decrease of action accuracy of unmanned forklift and making initial work efficient. The initial setting method of unmanned forklift has: a step of acquiring a measurement value of ground inclination of a stop position at which the unmanned forklift stops when performing unloading on a goods shelf; a step of setting a stop position detecting a predetermined inclination mode as a fine adjustment position according to the acquired measurement value; a step of making the unmanned forklift perform unloading according to an action program at the fine adjustment position and measuring the offset amount of a pallet unloaded by the unmanned forklift; and a step of correcting the instruction value of the unmanned forklift at the stop position based on the measured offset amount.

Description

Technical Field

[0001] This invention relates to an initial setup method for unmanned forklifts. Background Technology

[0002] Unmanned forklifts, for example, use laser sensors to measure the distance to surrounding objects, determine the location of the machine and the location of the goods (pallets), and automatically perform unloading and retrieval operations on the racks (e.g., see Patent Document 1).

[0003] To ensure that automated forklifts can correctly perform unloading and picking operations, it is necessary to improve the accuracy of their position determination. Therefore, when introducing them into work areas such as warehouses, it is necessary to perform an initial setting process (calibrating the forklifts' offset from the actual environment by having them actually move according to pre-programmed motions) to determine this offset.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2016-210586 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] In the operating area of ​​an automated forklift, multiple racks are connected in the left-right direction. The area containing one pallet in the left-right direction of the rack is called a "link," and the area containing one pallet in the vertical direction is called a "layer." Additionally, when multiple racks are arranged in the front-back direction, the area containing one pallet in that direction is called a "column." In previous initial setup operations, for all locations (stop positions) where the automated forklift performs unloading and picking, i.e., each column of the rack, the offset was measured by actually unloading at each link and each level. However, this operation was cumbersome and required a significant amount of time.

[0009] Furthermore, to improve operational efficiency, it is considered to eliminate intervals in the initially set offset measurement locations. For example, for each row of shelves, a method is considered to measure the offset only by connecting three locations: the two ends in the left-right direction and the center. However, in this method, if there are discontinuous sections of the ground in the left-right direction (e.g., a U-shaped or V-shaped ground) or in the front-back direction (e.g., a ground that causes the automated forklift to tilt forward), the offset cannot be measured. Therefore, when the automated forklift unloads goods on such sloping ground, there is a risk of pallets coming into contact with each other or with the shelves.

[0010] The present invention was made in view of the following problem: to provide an initial setup method for an unmanned forklift that can suppress the decrease in the motion accuracy of the unmanned forklift and make the initial operation more efficient.

[0011] means for solving problems

[0012] According to one technical solution of the present invention, the initial setting method of an unmanned forklift includes the following steps: obtaining a measurement value of the ground tilt at the stopping position where the unmanned forklift stops unloading from a rack; setting the stopping position where a predetermined tilt pattern is detected as a precision adjustment position based on the obtained measurement value; causing the unmanned forklift to unload according to an action program at the precision adjustment position, and measuring the offset of the pallet unloaded by the unmanned forklift; and correcting the command value of the unmanned forklift at the stopping position based on the measured offset.

[0013] Invention Effects

[0014] The initial setup method for the unmanned forklift according to the present invention can suppress the reduction of the motion accuracy of the unmanned forklift and make the initial operation more efficient. Attached Figure Description

[0015] Figure 1 This is a diagram showing the operating area of ​​an unmanned forklift according to one embodiment of the present invention.

[0016] Figure 2 This is a diagram illustrating the structure of a fixture for initial setup operations and an unmanned forklift according to one embodiment of the present invention.

[0017] Figure 3 This is a first flowchart illustrating an example of an initial setting method according to an embodiment of the present invention.

[0018] Figure 4 This is a second flowchart illustrating an example of an initial setting method according to an embodiment of the present invention.

[0019] Figure 5 The first figure is an example of a tilting pattern according to an embodiment of the present invention.

[0020] Figure 6 The second figure is an example of a tilting pattern according to one embodiment of the present invention.

[0021] Figure 7 The third figure shows an example of a tilting pattern according to an embodiment of the present invention.

[0022] Figure 8The first figure shows an example of a precise adjustment position setting according to an embodiment of the present invention.

[0023] Figure 9 This is a third flowchart illustrating an example of an initial setting method according to an embodiment of the present invention.

[0024] Figure 10 The fourth figure is an example of a tilting pattern according to an embodiment of the present invention.

[0025] Figure 11 The second figure shows an example of a precise adjustment position setting according to an embodiment of the present invention.

[0026] Figure 12 This is a diagram illustrating an example of offset measurement according to one embodiment of the present invention. Detailed Implementation

[0027] The following is for reference Figures 1-12 An initial setup method for an unmanned forklift according to one embodiment of the present invention will be described.

[0028] (Regarding the operating area of ​​the unmanned forklift)

[0029] Figure 1 This is a diagram showing the operating area of ​​an unmanned forklift according to one embodiment of the present invention.

[0030] like Figure 1 As shown, multiple racks R are installed in the operating area of ​​the unmanned forklift 90. Figure 1 In the example, multiple shelves R (R1, R2, ...) are connected in the left-right direction (Y direction, also referred to as the width direction). In addition, each shelf R (R1, R10) is arranged back-to-back in the front-back direction (X direction, also referred to as the depth direction).

[0031] For example, shelf R1 has two links (links A1 and A2) in the horizontal direction (Y direction) representing areas for placing pallets P. Additionally, shelf R1 has three layers (layers B1, B2, and B3) in the vertical direction (Z direction) representing areas for placing pallets P. Furthermore, shelf R1 has one column (column C1) in the depth direction (X direction) representing an area for placing pallets P. That is, shelf R1 has a total of six pallet P placement locations. Other shelves R have the same structure. It should be noted that the number of links, layers, and columns of shelf R is just one example; in other embodiments, the number of links, layers, and columns of shelf R can be increased or decreased.

[0032] The unmanned forklift 90 includes a main body 900, a lifting device 901, and forks 902. When unloading, the unmanned forklift 90 aligns its left-right (Fy direction) position with the predetermined left-right (Y direction) position of the link being unloaded, and stops with the side equipped with the forks 902 (-Fx side) facing the rack R. That is, the front of each link of the rack R becomes the stopping position of the unmanned forklift 90. Furthermore, in the following description, the same reference numerals are sometimes used to describe the link and the stopping position. For example, the stopping position corresponding to link A1 of rack R1 is also described as stopping position A1.

[0033] In addition, the unmanned forklift 90 moves the forks 902 in the vertical direction (Fz direction) and the front-back direction (Fx direction) via the lifting device 901 to perform unloading by placing the pallet P at the predetermined position on each layer of each link.

[0034] As described above, in the prior art initial setup method of the unmanned forklift 90, the unmanned forklift 90 actually unloads pallet P for all layers of all connections of the rack R, thereby measuring the offset between the target placement position and the actual placement position of pallet P. However, since multiple racks R are provided in the work area, the initial setup in the prior art is very time-consuming. Therefore, in the initial setup method of this embodiment, the ground inclination at each stop position of the unmanned forklift 90 is measured using a fixture for initial setup, and the parts where the offset of the unmanned forklift 90 is measured are periodically eliminated, thereby achieving efficiency. The details of the initial setup method of this embodiment will be described below.

[0035] (Regarding the clamps used for initial setup)

[0036] Figure 2 This is a diagram illustrating the structure of a fixture for initial setup operations and an unmanned forklift according to one embodiment of the present invention.

[0037] First, the fixture 10 used for initial setup in this embodiment will be described. The fixture 10 simulates an unmanned forklift 90 actually used in the work area. The fixture 10 is used by the operator to measure the inclination of the ground at each stopping position of the unmanned forklift 90.

[0038] like Figure 2 As shown, the clamp 10 includes a main body 101, a rear wheel simulation part 102, a front wheel simulation part 103, a first inclinometer 104, a second inclinometer 105, a positioning tool 106, and a handle 107.

[0039] The main body 101 is composed of a first part 101a and a second part 101b, and is T-shaped when viewed from above. The first part 101a is the head of the T, which is a frame extending along the left-right direction (Y direction) of the clamp 10. The second part 101b is the leg of the T, which is a frame extending from the first part 101a along the front-back direction (X direction) of the clamp 10.

[0040] The rear wheel simulation unit 102 is a pair of tires (casters) mounted on the lower part of the first part 101a of the main body 101. The rear wheel simulation unit 102 is configured such that the distance between the tires in the left and right direction (tread TR1) is consistent with the tread TR9 of the rear wheel RW of the unmanned forklift 90.

[0041] The front wheel simulation unit 103 is mounted below the second part 101b of the main body 101. The front wheel simulation unit 103 is, for example, a leg made of rubber or the like. The distance between the front wheel simulation unit 103 and the rear wheel simulation unit 102 (wheelbase WB1) is the same as the wheelbase WB9 of the front wheel FW and the rear wheel RW of the unmanned forklift.

[0042] The first inclinometer 104 is mounted on the first part 101a of the main body 101 to measure the tilt of the fixture 10 in the left-right direction (Y direction).

[0043] The second inclinometer 105 is mounted on the second part 101b of the main body 101 to measure the tilt of the fixture 10 in the front-back direction (X direction).

[0044] Positioning tool 106 is a marker used to determine the position of each link of clamp 10 relative to shelf R. For example... Figure 2 As shown, the positioning tools 106 are located in the center and on the left and right sides. The left and right positioning tools 106 are configured to correspond to the positions of the rear wheel simulation unit 102.

[0045] Handle 107 is provided for the operator to hold and pull, thereby moving clamp 10. For example... Figure 2 As shown, the handle 107 can be a rope-like structure or a frame extending upward from the second part 101b of the main body 101.

[0046] (Regarding the initial setup method)

[0047] Figure 3 This is a first flowchart illustrating an example of an initial setting method according to an embodiment of the present invention.

[0048] The following is for reference Figure 3 The initial setup steps for the unmanned forklift 90 are explained in detail.

[0049] First, the operator performing the initial setup sets up the clamp 10 at the stop position of the unmanned forklift 90 and measures the inclination of the ground at each stop position (step S10).

[0050] For example, performing shelf R1 ( Figure 1 The first connection A1 (stop position A1) is measured. The operator sets the clamp 10 at the stop position A1. At this time, the operator uses the positioning tool 106 of the clamp 10 as a marker to adjust the position of the clamp 10 so that the positions of the rear wheel simulation part 102 and the front wheel simulation part 103 of the clamp 10 are consistent with the positions of the front wheel FW and the rear wheel RW when the unmanned forklift 90 unloads goods to connection A1.

[0051] When the operator sets the clamp 10 to the stop position A1, the first inclinometer 104 is used to obtain the left and right directions of the stop position A1. Figure 1 The operator obtains the measured value (θX) of the ground tilt in the Y direction. Additionally, the operator uses a second inclinometer 105 to obtain the forward and backward direction (θX) of the stop position A1. Figure 1 The measured value of the tilt of the ground in the X direction (θY).

[0052] The operator also uses clamp 10 to measure the inclination of the ground in the left-right and front-back directions at other stopping positions.

[0053] In this embodiment, the clamp 10 is configured such that the rear wheel simulation unit 102 and the front wheel simulation unit 103 are identical to the tire tread TR9 and wheelbase WB9 of the unmanned forklift 90. Therefore, the clamp 10 can simulate the degree of tilt of the unmanned forklift 90 when it is stopped at each stop position.

[0054] Next, the operator sets the precise adjustment position (step S20) for each stop position, which requires measuring the offset to actually move the unmanned forklift 90. For details on the steps for setting the precise adjustment position, please refer to... Figures 4 to 11 Please provide an explanation.

[0055] Figure 4 This is a second flowchart illustrating an example of an initial setting method according to one embodiment of the present invention.

[0056] Figure 4 The flowchart shows the left and right directions with an eye toward the ground. Figure 1 The steps for setting the precise tilt position in the Y direction. Figure 3 In step S10, when the tilt measurements of all stop positions are obtained, the operator follows... Figure 4 The steps involve precisely adjusting the position settings.

[0057] The operator targets the left and right directions ( Figure 1The operator checks the stopping positions of multiple shelves R connected along the Y direction to identify any points where the tilt pattern is discontinuous (step S201). If the measured value (θX) of the first inclinometer 104 is a positive value above the upper limit (e.g., θX ≥ +0.1 degrees), the operator determines that the ground is tilted to the lower right; if it is a negative value below the lower limit (e.g., θX ≤ -0.1 degrees), the operator determines that the ground is tilted to the lower left. Furthermore, if the measured value (θX) of the first inclinometer 104 is within the range of the lower limit to the upper limit (e.g., -0.1 degrees < θX < +0.1 degrees), the operator determines that the ground is level.

[0058] Figure 5 The first figure is an example of a tilt pattern representing one embodiment of the present invention.

[0059] like Figure 5 As shown in the example, the stop position A1 of the shelf R1 is tilted to the lower right, and the stop position A2 is tilted to the lower left. Therefore, the Z-axis of stop position A1 is tilted to the right (+Y side). Furthermore, the Z-axis of stop position A2 is tilted to the left (-Y side), in the opposite direction to stop position A1. That is, at stop positions A1 and A2, the Z-axis is tilted in a convex (or convex) pattern towards the center of the shelf R1.

[0060] If an automated forklift 90 is used in a rack R1 with this tilt pattern, the Fz axis of the automated forklift 90 tilts to the right (+Fy side) at stop position A1 and to the left (-Fy side) at stop position A2. Therefore, when unloading, the automated forklift 90 tends to place pallets P closer to the center of rack R1 than the target placement position. This tendency is particularly strong towards the upper layers, thus creating a risk of pallets P contacting each other near the center of rack R1 in the topmost layer B3. For stop positions A1 and A2 where there is a risk of contact, the offset of the automated forklift 90 needs to be precisely measured, and its operation corrected accordingly to reduce the risk of contact.

[0061] Therefore, when the operator detects that the tilt pattern becomes discontinuous (in the opposite direction) in the continuous left and right stop positions A1 and A2 (step S201: Yes), these stop positions A1 and A2 are set as precision adjustment positions (step S202).

[0062] Figure 6 The second figure is an example of a tilting pattern representing one embodiment of the present invention.

[0063] like Figure 6As shown in the example, the stop position A3 of shelf R2 is tilted to the lower left, and the stop position A4 is tilted to the lower right. Therefore, the Z-axis of stop position A3 is tilted to the left (-Y side). Conversely, the Z-axis of stop position A4 is tilted to the right (+Y side), in the opposite direction to stop position A3. That is, at stop positions A3 and A4, the Z-axis is tilted in a concave (V-shaped) pattern towards the outside of shelf R2.

[0064] If an automated forklift 90 is used on rack R2 with this tilt pattern, the Fz axis of the automated forklift 90 tilts to the left (-Fy side) at stop position A3 and to the right (+Fy side) at stop position A4. Therefore, when unloading, the automated forklift 90 tends to place the pallet P on the outside of rack R2, closer to the target placement position than intended. This tendency is particularly strong towards the upper shelves, thus creating a risk of contact between the pallet P and rack R2 near both ends in the top shelf B3. For stop positions A3 and A4 where contact risk exists, the offset of the automated forklift 90 needs to be precisely measured, and its operation corrected accordingly to reduce the contact risk.

[0065] Therefore, if the operator detects that the tilt pattern becomes a discontinuous (opposite direction) "V-shape" at the continuous left and right stop positions A3 and A4 (step S201: Yes), then these stop positions A3 and A4 are set as precision adjustment positions (step S202).

[0066] Figure 7 The third figure is an example of a tilting mode representing one embodiment of the present invention.

[0067] like Figure 7 As shown in the example, at stop positions A7 and A8 of shelf R4, the ground slopes in the same direction (both downward to the left). If the operator detects the same continuous (certain tilting) tilt pattern at consecutive stop positions A5 and A6 (step S201: No), then these stop positions A5 and A6 will not be set as precision adjustment positions. The same applies when multiple stop positions are consecutively horizontal.

[0068] In addition, for continuous racks formed by connecting multiple racks R, the operator further adjusts the left and right directions ( Figure 1 The two ends and the center of the stop position in the X direction are set as the precision adjustment position (step S203).

[0069] Figure 8 The first figure shows an example of a precise adjustment position setting according to one embodiment of the present invention.

[0070] like Figure 8As shown, two continuous racks, A and B, are set up in the work area. Continuous rack A consists of racks located in the left and right directions (…). Figure 1 The continuous shelving B consists of shelves R1 to R5 connected in the Y direction. Figure 1 The racks (R6 to R10) are connected in the Y direction. Continuous racks A and B are not connected.

[0071] For example, the operator sets the stop positions A1 and A10 at both ends and the stop position A6 in the middle of continuous rack A as precision adjustment positions. Similarly, the operator sets the stop positions A11 and A20 at both ends and the stop position A16 in the middle of continuous rack B as precision adjustment positions. Figure 4 Step S203). Additionally, as... Figure 8 As shown in the example, when there are an even number of stop positions A1 to A10, one of the stop positions A5 or A6 of the central shelf R3 is selected and set as the precision adjustment position. Which one is selected can be arbitrarily decided by the operator.

[0072] In addition, Figure 8 The diagram shows examples of the Z-axis tilt at various stopping positions of continuous racks A and B. For continuous rack A, the stopping positions A1 and A2 of rack R1 have a discontinuous tilt pattern (H-shape). Figure 5 ()( Figure 4 Step S201: Yes). The stopping positions A3 and A4 of shelf R2 are discontinuous V-shaped tilt patterns. Figure 6 ()( Figure 4 Step S201: Yes). Therefore, the operator sets these stop positions A1 to A4 as precision adjustment positions ( Figure 4 Step S202).

[0073] Regarding continuous shelving B, the tilting patterns of stop positions A12 of shelving R6 and A13 of shelving R7 are discontinuous (ha-shaped). Thus, regarding the continuous stop positions A12 and A13 spanning the shelving, the tilting patterns are discontinuous (…). Figure 4 Step S201: Yes), these stop positions A12 and A13 can also be set as precision adjustment positions ( Figure 4 Step S202).

[0074] For continuous rack A, the stopping positions A5 to A10 of racks R3 to R5 are in a certain inclined pattern for continuous operation. Figure 4Step S201: No). Therefore, the stop positions A5, A7, A8, and A9 of these stop positions A5 to A10 that do not belong to the ends and center of continuous rack A are not set as precision adjustment positions and are excluded at intervals. Similarly, for continuous rack B, the stop positions A14 to A20 of racks R7 to R10 are continuously operated in a certain inclined tilting pattern ( Figure 4 Step S201: No). Among these stop positions A14 to A20, the stop positions A14, A15, A17, A18, and A19 that do not belong to the end and center of the continuous shelf B are not set as precision adjustment positions and are excluded at intervals. Therefore, for stop positions where the tilt pattern does not change, the measurement of the offset can be omitted.

[0075] Figure 9 This is a third flowchart illustrating an example of an initial setting method according to an embodiment of the present invention.

[0076] Figure 9 The flowchart shows the forward and backward directions with an eye toward the ground. Figure 1 The steps involve precisely adjusting the tilt position in the X direction. The operator then... Figure 4 Follow the steps Figure 9 The next step involves further precise adjustment of the position setting. Additionally, in other embodiments, the operator can also... Figure 4 Before the steps Figure 9 The steps.

[0077] For each stopping position of multiple racks R, the operator confirms the side of the forks 902 of the unmanned forklift 90 (the side facing the rack R to be unloaded) Figure 1 The -Fx side) is 900 times larger than the main body side ( Figure 1 The presence or absence of a tilting mode (step S211) where the +Fx side is lower (i.e., when the R side (-X side) of the rack at the stop position is set as the front side, the unmanned forklift 90 is in a forward tilting state towards the front side of the stop position). If the operator's measured value (θY) of the second inclinometer 105 is a positive value above the upper limit (e.g., θY ≥ +0.15 degrees), it is determined that the forklift 90 is tilted in a way that makes the fork 902 side of the unmanned forklift 90 higher than the main body 900 side (the unmanned forklift 90 is in a backward tilting posture towards the rear side (+X side) of the stop position). If the measured value is a negative value below the lower limit (e.g., θY ≤ -0.15 degrees), it is determined that the forklift 90 is tilted in a way that makes the main body 900 side of the unmanned forklift 90 higher than the fork 902 side (the unmanned forklift 90 is in a forward tilting posture towards the front side (-X side) of the stop position). In addition, if the measurement value of the second inclinometer 105 is within the range of the lower limit to the upper limit (e.g., -0.15 degrees < θY < +0.15 degrees), the operator judges the ground to be level.

[0078] Figure 10 The fourth figure is an example of a tilting mode representing one embodiment of the present invention.

[0079] like Figure 10 As in the example, the unmanned forklift 90 unloads goods from rack R2. The side of rack R2 (-X side) at the stopping positions A3 and A4 is the front side, and the side furthest from rack R2 (+X side) is the rear side. Additionally, in... Figure 10 In the example, the ground at the stopping positions A3 and A4 of shelf R2 is tilted in such a way that the front side (-X side) is lower than the rear side (+X side).

[0080] If an automated forklift 90 is used on rack R2 with this tilting pattern, the Fz axis of the automated forklift 90 will be tilted forward (towards the -Fx side) at the stop positions A3 and A4. Therefore, when unloading, the automated forklift 90 will be positioned further inwards from the target loading position on rack R2. Figure 10 The forklift 90 tends to place pallet P on the X-side. This tendency is particularly strong towards the upper layers, thus creating a risk of contact between pallet P and a rack R (e.g., rack R6) located behind rack R2 when unloading pallet P onto the uppermost layer B3. For the stop positions A3 and A4 where contact risk exists, precise measurement of the forklift 90's offset is required to correct its movement and reduce the risk of contact.

[0081] Therefore, if the operator detects that the unmanned forklift 90 has entered a tilting mode that forms a forward tilt (step S211: Yes), then the stop position A3, A4 is set as a precision adjustment position (step S212).

[0082] In addition, the operator further sets the stop positions at both ends and the center of the continuous racks A and B as precision adjustment positions (step S213). This process is related to... Figure 4 The steps are the same as in step S203. Additionally, in the preliminary execution... Figure 4 If the two ends and the center of the continuous shelves A and B have already been set to the precision adjustment position, step S213 can be omitted.

[0083] Figure 11 The second figure shows an example of a precise adjustment position setting according to one embodiment of the present invention. Figure 11 Examples of Z-axis tilt and precision adjustment settings for continuous rack A (racks R1 to R5) and continuous rack B (racks R6 to R10) are shown. Figure 11 Continuous racks A, B and Figure 8 The continuous shelving units A and B are the same.

[0084] For example, the operator sets the stop positions A1 and A10 at both ends and the stop position A6 in the middle of continuous rack A as precision adjustment positions. Similarly, the operator sets the stop positions A11 and A20 at both ends and the stop position A16 in the middle of continuous rack B as precision adjustment positions. Figure 4 Step S213).

[0085] For continuous rack A, the tilt pattern of the stopping positions A3 and A4 of rack R2 is forward tilt ( Figure 10 ()( Figure 9 Step S211: Yes). Therefore, the operator sets these stop positions A3 and A4 as precision adjustment positions ( Figure 9 Step S212).

[0086] In addition, the tilting pattern of other stop positions A1-A2, A5-A10 of continuous rack A and stop positions A11-A20 of continuous rack B is not forward tilting. Figure 9 Step S211: No). Therefore, stop positions A1-A2, A5-A10, and A11-A20 that are not at the end or center are not set as precision adjustment positions and are periodically eliminated. Thus, for stop positions that are not forward-leaning, the measurement of offset can be omitted.

[0087] In addition, Figure 4 as well as Figure 9 In the steps shown for setting the precision adjustment position, the operator can also input the tilt measurement values ​​of each stop position into the computer (not shown), so that the computer can automatically perform the tilt mode calculation and the setting of the precision adjustment position.

[0088] Once the precise adjustment position setting is complete, the operator returns. Figure 3 The steps involve measuring the offset at each precision adjustment position (step S30). Specifically, for each layer B1 to B3 of the connection that becomes a precision adjustment position, the operator causes the unmanned forklift 90 to actually unload the pallet P according to a predetermined action procedure, and measures the offset between the target placement position and the actual placement position of the pallet P.

[0089] Figure 12 This is a diagram illustrating an example of offset measurement in one embodiment of the present invention.

[0090] like Figure 12As shown, the operator marks each layer of the connection, which is set to a precise adjustment position, with guide section G1a indicating the central reference position, guide section G1b indicating the left reference position, and guide section G1c indicating the right reference position. Additionally, the operator marks the tray P with guide section G2a indicating the central reference position, guide section G2b indicating the left reference position, and guide section G2c indicating the right reference position. The guide sections G2a to G2c of the tray P are configured such that, when the tray P is correctly placed in the target placement position, their positions in the left-right and front-back directions coincide with those of guide sections G1a to G1c (the front end of the arrow of guide section G1a to G1c coincides with the lower end of guide sections G2a to G2c).

[0091] In addition, "left" and "right" refer to the left (+Fy side) and right (-Fy side) as viewed from the direction the unmanned forklift is traveling in the +Fx direction.

[0092] Here, as an example, we will explain the situation where the operator measures the offset in link A1 and layer B3 of rack R1. First, the operator uses an unmanned forklift 90 to unload pallets P with guides G2a to G2c from link A1 and layer B3 of rack R1.

[0093] When pallet P is loaded, the operator first measures the central offset (D1). The operator then measures the left-right offset (Fy direction) ΔFy of the guide section G1a at the target loading position and the guide section G2a of pallet P. Figure 12 In the example, the left-right offset ΔFy in layer B3 of A1 is "-3mm".

[0094] Next, the operator measures the left-side offset (D2) and right-side offset (D3) of the unmanned forklift 90. The operator also measures the front-rear offset (Fx direction) ΔFx of the guide section G1b at the target loading position and the guide section G2b of the pallet P. Similarly, the operator measures the front-rear offset (Fx direction) ΔFx of the guide section G1c at the target loading position and the guide section G2c of the pallet P. Figure 12 In the example, the left-side forward / backward offset ΔFx in layer B3 of A1 is "30mm", and the right-side forward / backward offset ΔFx is "36mm". Furthermore, the operator calculates the rotation angle θFz of the unmanned forklift around the Z-axis based on the left-side forward / backward offset ΔFx (D2), the right-side forward / backward offset ΔFx (D3), the distance between the guide section G2b and guide section G2c of pallet P.

[0095] Next, the operator corrects the command values ​​of the unmanned forklift 90 based on the measured offsets (left-right offset ΔFy, front-back offset ΔFx, and Fz axis offset ΔθFz) (step S40). The following will use... Figures 5-7 and Figure 10 For example, let's illustrate one instance of the content to be corrected.

[0096] like Figure 5 As shown, assume that the stop positions A1 and A2 of the rack R1 are tilted in a "ハ" shape. In this case, the operator corrects the command value of the travel center of the automated forklift 90 (the amount of movement of the rack R in the left-right direction) based on the measured offset. For example, the operator corrects the command value by shifting the travel center of the automated forklift 90 5mm to the right (-Fy side) of the automated forklift 90 at the stop position A1 of the rack R1. Additionally, the operator corrects the command value by shifting the travel center of the automated forklift 90 5mm to the left (+Fy side) of the automated forklift 90 at the stop position A2 of the rack R1.

[0097] like Figure 6 As shown, the stop positions A3 and A4 of rack R2 are tilted in a V-shape. In this case, the operator corrects the command value of the travel center (the amount of movement of rack R in the left and right directions) of the automated forklift 90 based on the measured offset. For example, at the stop position A3 of rack R2, the operator corrects the command value by shifting the travel center of the automated forklift 90 5mm to the left (+Fy side). Similarly, at the stop position A4 of rack R2, the operator corrects the command value by shifting the travel center of the automated forklift 90 5mm to the right (-Fy side).

[0098] like Figure 7 As shown, the stop positions A7 and A8 of shelf R4 are tilted at a certain angle and are not set as precision adjustment positions (offset not measured). Therefore, the operator estimates the offset for these stop positions where the offset was not measured, based on the offset of the adjacent stop positions that are set as precision adjustment positions. Figure 8 In the example, the offset is not measured for the stop positions A7-A9 of the continuous rack A. In this case, the operator calculates the offset (estimated offset) of the intermediate stop positions A7-A9 based on the offsets of stop positions A6 and A10. Then, the operator corrects the command value of the unmanned forklift 90 based on the calculated estimated offset. For example, as... Figure 7As shown, the operator corrects the command value by shifting the travel center of the automated forklift 90 10mm to the left (+Fy side) of the automated forklift 90 at the stop position A7 of rack R4. Additionally, the operator corrects the command value by shifting the travel center of the automated forklift 90 5mm to the left (+Fy side) of the automated forklift 90 at the stop position A8 of rack R2.

[0099] like Figure 10 As shown, the stop positions A3 and A4 of rack R2 have the unmanned forklift 90 tilted forward. In this case, the operator, for example, corrects the command value of the distance between the unmanned forklift 90 and rack R2 (the amount of movement in the depth direction of rack R) based on the measured offset.

[0100] In addition, the operator can also input the measured value of the offset into the computer (not shown), so that the computer can automatically perform calculations of the inferred offset at the stop position that is not set as a precision adjustment position, calculations of the correction amount of the command value, etc.

[0101] (Effects)

[0102] As described above, the initial setting method for the unmanned forklift 90 according to this embodiment includes: a step of acquiring a measurement value of the ground tilt at the stop position (S10); a step of setting the stop position where a predetermined tilt pattern is detected as a precision adjustment position based on the acquired measurement value (S20); a step of causing the unmanned forklift 90 to perform unloading according to the operation program at the precision adjustment position and measuring the offset of the pallet P unloaded by the unmanned forklift 90 (S30); and a step of correcting the command value of the unmanned forklift 90 at the stop position based on the measured offset (S40).

[0103] Therefore, by precisely measuring the offset and correcting the command value at the stop position of the predetermined tilting pattern, the reduction in the motion accuracy of the unmanned forklift 90 can be suppressed. On the other hand, the measurement of the offset at other stop positions can be omitted, making the initial setting of the unmanned forklift 90 more efficient.

[0104] In addition, in the step of setting the precision adjustment position (S20), the stop positions corresponding to the two ends and the center of the continuous shelf in the left and right directions are further set as precision adjustment positions.

[0105] This allows the minimum stopping position of the continuous rack to be set as a precise adjustment position. Therefore, based on the offsets at the two ends and the center of the continuous rack, the offsets at other stopping positions can be estimated and supplemented.

[0106] In addition, in the step of setting the precision adjustment position (S20), if a tilting pattern is detected in which the ground at consecutive stop positions in the left and right directions tilts in the opposite direction (becoming a 'ha' or 'V' shape), these stop positions are set as precision adjustment positions.

[0107] In this way, the offset can be precisely measured at the stopping position where the tilt tendency changes, and the command values ​​related to the actions of the unmanned forklift 90 can be appropriately corrected. This helps to suppress the reduction in the action accuracy of the unmanned forklift 90.

[0108] In addition, in the step of setting the precision adjustment position (S20), if it is detected that the ground at the stop position is in a tilt mode (forward tilt) where the front side of the unmanned forklift 90 is lower than the rear side, the stop position is set as the precision adjustment position.

[0109] In this way, in situations where the unmanned forklift 90 tilts forward, the offset can be precisely measured, and the command values ​​related to the unmanned forklift 90's movements can be appropriately corrected. This helps to suppress any decrease in the movement accuracy of the unmanned forklift 90.

[0110] In addition, in the step of acquiring the measurement value (S10), the wheel positions of the unmanned forklift 90 in the left and right directions and the front and back directions are simulated. The clamp 10, which is equipped with a first inclinometer 104 for measuring the tilt in the left and right directions and a second inclinometer 105 for measuring the tilt in the front and back directions, is placed at the stop position to acquire the measurement value of the tilt of the ground at the stop position.

[0111] In this way, without actually moving the unmanned forklift 90, it is possible to easily simulate the degree of tilt of the unmanned forklift 90 at each stopping position.

[0112] In addition, in the step of correcting the command value (S40), for a stop position that is not set as a precision adjustment position, the command value is corrected based on an estimated offset estimated based on the offset measured at the stop position set as a precision adjustment position to the left or right.

[0113] In this way, even for stop positions where offset measurement is omitted, the degree of offset can be estimated based on the offset of other stop positions. Therefore, even without omitting offset measurement, the reduction in the motion accuracy of the unmanned forklift 90 can be suppressed.

[0114] As described above, embodiments of the present invention have been illustrated, but these embodiments are merely examples and are not intended to limit the scope of the invention. The embodiments described above can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention, and are also included within the scope of the claims and their equivalents.

[0115] <Postscript>

[0116] The initial setup method for the unmanned forklift described in the above embodiments can be mastered as follows.

[0117] (1) According to a first aspect of the present invention, the initial setting method of the unmanned forklift (90) includes: a step (S10) of acquiring a measurement value of the ground tilt at the stop position where the unmanned forklift (90) stops unloading from the rack; a step (S20) of setting the stop position where a predetermined tilt pattern is detected as a precision adjustment position based on the acquired measurement value; a step (S30) of causing the unmanned forklift (90) to perform unloading according to an action program at the precision adjustment position, and measuring the offset of the pallet unloaded by the unmanned forklift (90); and a step of correcting the command value of the unmanned forklift at the stop position based on the measured offset.

[0118] In this way, for the stop position of the predetermined tilting pattern, the offset is precisely measured and the command value is corrected, thereby suppressing the reduction of the motion accuracy of the unmanned forklift. On the other hand, the measurement of offset at other stop positions can be omitted, making the initial setting of the unmanned forklift more efficient.

[0119] (2) According to the second aspect of the present invention, in the step of storing the precision adjustment position (S20), the two ends and the corresponding stop positions in the left and right directions of the continuous shelf formed by connecting multiple shelves are further set as precision adjustment positions.

[0120] This allows the minimum stopping position of the continuous rack to be set as a precise adjustment position. Therefore, based on the offsets at the two ends and the center of the continuous rack, the offsets at other stopping positions can be estimated and supplemented.

[0121] (3) According to the third aspect of the present invention, in the step of setting the precision adjustment position (S20), if a tilting pattern is detected in which the ground at the first stop position and the second stop position in the left and right directions tilts in opposite directions respectively, the first stop position and the second stop position are set as precision adjustment positions.

[0122] In this way, the offset can be precisely measured at the stopping position where the tilt tendency changes, and the command values ​​related to the unmanned forklift's movements can be appropriately corrected. This helps to suppress the reduction in the operational accuracy of the unmanned forklift.

[0123] (4) According to the fourth technical solution of the present invention, in the step of setting the precision adjustment position (S20), when it is detected that the ground at the stop position is in an inclined mode where the front side of the unmanned forklift (90) is lower than the rear side, the stop position is set as the precision adjustment position.

[0124] In this way, in situations where the automated forklift tilts forward, the offset can be precisely measured, and the command values ​​related to the automated forklift's movements can be appropriately corrected. This helps to suppress any decrease in the automated forklift's operational accuracy.

[0125] (5) According to the fifth aspect of the present invention, in the step (S10) of acquiring the measurement value, the wheel positions of the unmanned forklift (90) in the left-right direction and the front-back direction are simulated, and the clamp (10) equipped with a first inclinometer (104) for measuring the tilt in the left-right direction and a second inclinometer (105) for measuring the tilt in the front-back direction is placed at the stop position to acquire the measurement value of the tilt of the ground at the stop position.

[0126] In this way, without actually moving the unmanned forklift, it is possible to easily simulate the degree to which the unmanned forklift tilts at each stopping position.

[0127] (6) According to the sixth aspect of the present invention, in the step (S40) of correcting the command value, for a stop position that is not set as a precision adjustment position, the command value is corrected based on an estimated offset calculated from the offset measured at the stop position where the precision adjustment position is set to be located to the left or right.

[0128] In this way, even for stop positions where offset measurement is omitted, the degree of offset can be estimated based on the offset of other stop positions. Therefore, even without omitting offset measurement, the reduction in the motion accuracy of the unmanned forklift can be suppressed.

[0129] [Symbol Explanation]

[0130] 10: Fixtures;

[0131] 101: Main body;

[0132] 101a: Part One;

[0133] 101b: Part Two;

[0134] 102: Rear wheel simulation unit;

[0135] 103: Front wheel simulation unit;

[0136] 104: First Inclinometer;

[0137] 105: Second Inclinometer;

[0138] 106: Location tools;

[0139] 107: Handle;

[0140] 90: Unmanned forklift;

[0141] 900: Main body;

[0142] 901: Lifting device;

[0143] 902: Forklift;

[0144] P: tray;

[0145] R: Shelf.

Claims

1. An initial setting method of a fork truck, wherein the initial setting method of the fork truck has: a step of acquiring a measurement value of a ground inclination of a stop position at which the fork truck stops when performing unloading of a shelf; a step of setting a stop position in which a predetermined inclination pattern is detected as a fine adjustment position, based on the acquired measurement value; a step of causing the fork truck to perform unloading in accordance with a movement program at the fine adjustment position, and measuring a shift amount of a pallet unloaded by the fork truck; and a step of correcting an instruction value of the fork truck at the stop position based on the measured shift amount.

2. The initial setting method of the fork truck according to claim 1, wherein in the step of storing the fine adjustment position, stop positions corresponding to both ends in a left-right direction and a center of a continuous shelf linked with a plurality of the shelves are also set as the fine adjustment position.

3. The initial setting method of the fork truck according to claim 1 or 2, wherein in the step of setting the fine adjustment position, in a case where it is detected that a first stop position and a second stop position which are continuous in the left-right direction have an inclination pattern in which the ground respectively inclines in a direction opposite to the left-right direction, the first stop position and the second stop position are set as the fine adjustment position.

4. The initial setting method of the fork truck according to claim 1 or 2, wherein in the step of setting the fine adjustment position, in a case where it is detected that the ground of the stop position is lower at a front side of the fork truck than at a rear side, the stop position is set as the fine adjustment position.

5. The initial setting method of the fork truck according to claim 1 or 2, wherein in the step of acquiring the measurement value, a wheel position in a left-right direction and a front-rear direction of the fork truck is simulated, a jig in which a first inclinometer which measures an inclination in the left-right direction and a second inclinometer which measures an inclination in the front-rear direction are mounted is disposed at the stop position, and a measurement value of an inclination of the ground of the stop position is acquired.

6. The initial setting method of the fork truck according to claim 1 or 2, wherein in the step of correcting the instruction value, for a stop position which is not set as the fine adjustment position, the instruction value is corrected based on an estimated shift amount calculated from the shift amount measured at a stop position which is set as the fine adjustment position located left and right. ​

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