Safety protection method and system in AGV operation

Abstract

The invention discloses a safety protection method and system in AGV operation, and relates to the technical field of AGV protection, and the method comprises the steps: obtaining an AGV speed interval; acquiring a deceleration detection area and a parking detection area of each speed by using a detection range analysis method; acquiring a detection deceleration multiplying power corresponding to each speed; when the AGV works, safety protection is carried out on the AGV; the method is used for solving the problems that in an existing safety protection method in AGV operation, an area scanning mode in the aspect of obstacle avoidance is conventional, the obstacle avoidance range of the AGV cannot be analyzed in combination with the real-time speed of the AGV, the scanning range and an analysis area cannot be adjusted according to the real-time state of the AGV during area scanning, the acceleration during deceleration cannot be effectively controlled, and the obstacle avoidance effect is affected. Therefore, the problem that the AGV cannot avoid obstacles in time or the scanning range is too large to cause resource waste is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of AGV protection, and specifically to a safety protection method and system for AGV operation. Background Art

[0002] An AGV (Automated Guided Vehicle) is an unmanned vehicle equipped with an automatic guidance device such as electromagnetic or optical; it can travel along a specified guidance path, has safety protection and various transfer functions, and is widely used in the fields of industrial logistics and manufacturing; the safety protection measures in AGV operation mainly include: basic safety protection, such as deviation from path protection, positioning anomaly protection, component failure protection, and communication failure protection, and also include protection measures such as obstacle avoidance and protection systems, and system docking and coordination.

[0003] The existing methods for safety protection in AGV operation usually scan the area where the AGV is located, obtain the positions where the AGV can safely stop and emergency stop during driving, and adjust the scanning range by identifying fixed obstacles in the area, so as to issue instructions in a timely manner in the face of emergencies. Although this improved method can enable the AGV to effectively avoid obstacles in different driving paths, the area scanning method is relatively conventional and cannot analyze the obstacle avoidance range of the AGV in combination with the real-time speed of the AGV, which will cause the scanning range and analysis area during area scanning to be unable to be adjusted according to the real-time state of the AGV, and the acceleration during deceleration cannot be effectively controlled, resulting in the problem that the AGV cannot avoid obstacles in time or the scanning range is too large, causing resource waste. For example, in the patent application with the publication number CN108388243A, a safety protection method and safety protection structure for an AGV robot are disclosed. This solution judges the situation of the driving path, and according to the judgment of the path, switches the corresponding safety scanning plane domain in real time and adjusts the size of the safety scanning plane to avoid the influence of fixed obstacles during driving. Other improvements in the safety protection of AGV operation are usually improvements in the anti-collision device, and still cannot solve the problem that the area scanning method in obstacle avoidance is relatively conventional, cannot analyze the obstacle avoidance range of the AGV in combination with the real-time speed of the AGV, which will cause the scanning range and analysis area during area scanning to be unable to be adjusted according to the real-time state of the AGV, and the acceleration during deceleration cannot be effectively controlled, resulting in the problem that the AGV cannot avoid obstacles in time or the scanning range is too large, causing resource waste. In view of this, it is necessary to improve the existing safety protection method for AGV operation. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems in the prior art to some extent. By providing a safety protection method and system for AGV operations, it is used to solve the problem in the existing safety protection methods for AGV operations that in terms of obstacle avoidance, the area scanning method is relatively conventional and cannot analyze the obstacle avoidance range of the AGV in combination with the real-time speed of the AGV. This will result in the scanning range and analysis area during area scanning being unable to be adjusted according to the real-time state of the AGV, and being unable to effectively control the acceleration during deceleration, thus causing the problem that the AGV cannot avoid obstacles in time or the scanning range is too large, leading to waste of resources.

[0005] To achieve the above object, in the first aspect, the present application provides a safety protection method for AGV operations, including the following steps:

[0006] Obtain the AGV speed range based on the running speed during AGV operations; use the detection range analysis method to obtain the laser detection type when the speed of the AGV is at each speed within the AGV speed range, and obtain the deceleration detection area and stop detection area corresponding to each laser detection type;

[0007] Obtain the historical detection records of the laser in the AGV and the historical deceleration records of the AGV at each speed within the AGV speed range, and obtain the detection deceleration ratio corresponding to each speed within the AGV speed range based on the historical detection records and historical deceleration records;

[0008] Based on the stop detection area, deceleration detection area, and the detection deceleration ratio corresponding to each speed within the AGV speed range, perform safety protection on the AGV during AGV operations.

[0009] Further, obtain the range that the running speed during AGV operations can reach, and denote it as the AGV speed range. The detection range analysis method includes:

[0010] Respectively obtain the deceleration acceleration during emergency braking of the AGV, the deceleration acceleration during normal braking of the AGV, and the minimum deceleration acceleration, and denote them as V1, V2, and V3 respectively;

[0011] For any speed α within the AGV speed range, start the AGV and adjust the speed of the AGV to speed α, and respectively obtain the distances traveled by the AGV when decelerated to a standstill by V1, V2, and V3, and denote them as the emergency braking distance, normal braking distance, and minimum deceleration distance respectively; establish a plane rectangular coordinate system, and denote it as the deceleration analysis coordinate system, where the unit of the X-axis of the deceleration analysis coordinate system is m, and the unit of the Y-axis is m; respectively mark the points (XX1, 0), (XX2, 0), and (XX3, 0) on the positive half-axis of the deceleration analysis coordinate system, where XX1 is the emergency braking distance, XX2 is the normal braking distance, and XX3 is the minimum deceleration distance.

[0012] Furthermore, the detection range analysis method further includes:

[0013] Denote the maximum length occupied in the horizontal direction in the front view of the AGV as the front detection width; use the line formed by the coordinate origin and the point (XX1, 0) as the length, and the line formed by the points (0, YY1) and (0, -YY1) as the width to form a rectangle, and denote it as the emergency braking rectangle, where YY1 is half of the front detection width.

[0014] Keep the side of the emergency braking rectangle that coincides with the Y-axis stationary, and expand the emergency braking rectangle proportionally until the length of the emergency braking rectangle is XX2, and denote the emergency braking rectangle at this time as the normal braking rectangle; keep the side of the emergency braking rectangle that coincides with the Y-axis stationary, and expand the emergency braking rectangle proportionally until the length of the emergency braking rectangle is XX3, and denote the emergency braking rectangle at this time as the maximum braking rectangle.

[0015] Furthermore, the detection range analysis method further includes:

[0016] When the area of the region in the normal braking rectangle that does not coincide with the emergency braking rectangle is denoted as the normal braking region, and the area of the region in the maximum range rectangle that does not coincide with the normal braking rectangle is denoted as the maximum braking region; denote the ratio of the area of the normal braking region to the area of the emergency braking rectangle as the deceleration judgment ratio, and denote the ratio of the area of the maximum braking region to the area of the normal braking region as the deceleration discrimination ratio.

[0017] When both the deceleration judgment ratio and the deceleration discrimination ratio are less than 1, denote the laser detection type of speed α as emergency braking detection, set the parking detection region of speed α as the minimum parking region, and set the deceleration detection region of speed α as the region in the maximum braking rectangle except the minimum parking region, where the minimum parking region is the region corresponding to the rectangle obtained by keeping the side of the emergency braking rectangle that coincides with the Y-axis stationary and shrinking the emergency braking rectangle proportionally until the length of the emergency braking rectangle is 2 / XX1.

[0018] When both the deceleration judgment ratio and the deceleration discrimination ratio are greater than or equal to 1, denote the laser detection type of speed α as double deceleration braking detection, set the parking detection region of speed α as the region where the emergency braking rectangle is located, and set the deceleration detection region of speed α as the region where the normal braking region and the maximum braking region are located.

[0019] Furthermore, the detection range analysis method further includes:

[0020] When only one of the deceleration judgment ratio and the deceleration discrimination ratio is greater than or equal to 1, the laser detection type of speed α is recorded as single deceleration braking detection, the parking detection area of speed α is set as the area where the emergency braking rectangle and the normal braking area are located, and the deceleration detection area of speed α is set as the area where the maximum braking area is located;

[0021] Obtain the parking detection area and the deceleration detection area corresponding to all speeds within the AGV speed range.

[0022] Furthermore, obtaining the detection deceleration magnification corresponding to each speed in the AGV speed range based on the historical detection record and the historical deceleration record includes:

[0023] For any speed α in any AGV speed range, obtain the historical detection record of the laser in the AGV and the historical deceleration record of the AGV when the AGV runs at speed α, and record them as the running detection record α and the running deceleration record α; when any object β is detected in the deceleration detection area of speed α in the running detection record α, record the time when the object β is detected in the running detection record α as the object detection time β, and record the time when the AGV starts to decelerate triggered by detecting the object β in the running deceleration record α as the object deceleration time β;

[0024] Based on the running detection record α, obtain the straight-line distance between the object β and the AGV at the object deceleration time β and the object detection time β respectively, and record them as the deceleration response distance and the detection response distance; record the acceleration of the AGV at the object deceleration time β in the historical running data of the AGV as the normal acceleration.

[0025] Furthermore, obtaining the detection deceleration magnification corresponding to each speed in the AGV speed range based on the historical detection record and the historical deceleration record also includes:

[0026] Obtain the normal acceleration, deceleration response distance, and detection response distance when all objects in the deceleration detection area of speed α are detected in the running detection record α; use the detection magnification algorithm to obtain the detection deceleration magnification corresponding to speed α, and the detection magnification algorithm includes: Where F is the detection deceleration magnification, q is the number of objects in the deceleration detection area of speed α detected in the running detection record α, and Li and Di are the deceleration response distance and the detection response distance of the i-th object in the deceleration detection area of speed α detected in the running detection record α respectively;

[0027] Obtain the detection deceleration magnification corresponding to all speeds within the AGV speed range.

[0028] Further, based on the parking detection area, the deceleration detection area, and the detection deceleration magnification corresponding to each speed within the AGV speed range, the safety protection of the AGV during operation includes:

[0029] When the AGV is running, align the real-time position and the operating direction of the AGV with the coordinate origin and the positive half-axis of the X-axis in the deceleration analysis coordinate system respectively; record the real-time speed of the AGV as speed γ, and use laser detection to perform real-time detection within the area corresponding to the maximum braking rectangle of speed γ.

[0030] Further, based on the parking detection area, the deceleration detection area, and the detection deceleration magnification corresponding to each speed within the AGV speed range, the safety protection of the AGV during operation further includes:

[0031] When there is an object in the parking detection area corresponding to speed γ, decelerate the AGV at V1 and perform a steering process, where the steering process includes: when the object in the parking detection area is in the first quadrant of the deceleration analysis coordinate, control the AGV to turn to the right; when the object in the parking detection area is in the fourth quadrant of the deceleration analysis coordinate, control the AGV to turn to the left; when the object in the parking detection area is on the positive half-axis of the X-axis of the deceleration analysis coordinate, control the AGV to turn to the direction of the quadrant with the least number of objects in the first quadrant and the fourth quadrant of the deceleration analysis coordinate;

[0032] When there is an object in the deceleration detection area corresponding to speed γ, decelerate the AGV with an acceleration δ when the object is detected by the laser, where δ is the product of the normal acceleration of speed γ and the detection deceleration magnification of speed γ.

[0033] In a second aspect, the present application further provides a safety protection system in AGV operation, including a laser detection module, a deceleration area analysis module, and a safety protection module;

[0034] The laser detection module is used to obtain multiple speed ranges based on the running speed during AGV operation; use the detection range analysis method to obtain the laser detection type when the speed of the AGV is in each speed range, and obtain the deceleration detection area and the parking detection area corresponding to each laser detection type;

[0035] The deceleration area analysis module is used to, when there is an object in the deceleration detection area, analyze the deceleration detection area using the deceleration judgment method based on laser detection, obtain the real-time position of the object in the deceleration detection area based on laser detection, and obtain multiple deceleration judgment criteria;

[0036] The safety protection module is used to perform safety protection on the AGV during AGV operation based on the parking detection area, the deceleration detection area, and the deceleration judgment criteria of each deceleration detection area.

[0037] Advantages of the present invention: First, based on the running speed of the AGV during operation, the AGV speed range is obtained; the detection range analysis method is used to obtain the laser detection types when the speed of the AGV is at each speed within the AGV speed range, and the deceleration detection area and the stop detection area corresponding to each laser detection type are obtained. The advantage of this is that by obtaining the AGV speed range and the deceleration detection area and the stop detection area corresponding to each speed, it is possible to obtain the area where the AGV is allowed to decelerate to avoid obstacles and the area where the AGV needs to stop to avoid obstacles when the AGV operates at different speeds, so as to effectively divide the obstacle avoidance methods when the AGV encounters obstacles during operation, preventing collisions when the distance between the obstacle and the AGV is relatively close, or wasting resources due to premature deceleration when the AGV is far from the obstacle; at the same time, by obtaining the deceleration detection area, it helps to clearly divide the area where the AGV decelerates to avoid obstacles in subsequent analysis, making the analysis result more in line with the actual operation situation;

[0038] The present application also obtains the historical detection records of the laser in the AGV and the historical deceleration records of the AGV at each speed in the AGV speed range, and obtains the detection deceleration magnification corresponding to each speed in the AGV speed range based on the historical detection records and the historical deceleration records; finally, based on the stop detection area, the deceleration detection area, and the detection deceleration magnification corresponding to each speed within the AGV speed range, safety protection is provided for the AGV during operation. The advantage of this is that by obtaining the detection deceleration magnification based on the historical detection records and the historical deceleration records, it is possible to obtain the magnification corresponding to the acceleration during deceleration at different speeds within the AGV speed range based on the positional relationship between the obstacle and the AGV during the process from when the laser used by the AGV scans an object to when the AGV executes deceleration, which helps to effectively control the acceleration during deceleration when the AGV decelerates to avoid obstacles, ensuring that the AGV can avoid obstacles in time at different operating speeds. Description of the Drawings

[0039] Figure 1 is the principle block diagram of the system of the present invention;

[0040] Figure 2 is the step flow chart of the method of the present invention;

[0041] Figure 3 is the schematic diagram of the deceleration analysis coordinate system of the present invention;

[0042] Figure 4 is the structural schematic diagram of the electronic device of the present invention. Detailed Embodiments

[0043] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0044] Example 1, please refer to Figure 1 As shown, the present application provides a safety protection system in AGV operation, including a laser detection module, a deceleration area analysis module, and a safety protection module;

[0045] The laser detection module is used to obtain multiple speed intervals based on the running speed during AGV operation; the detection range analysis method is used to obtain the laser detection type when the speed of the AGV is in each speed interval, and obtain the deceleration detection area and the stop detection area corresponding to each laser detection type;

[0046] Obtain the interval that the running speed of the AGV can reach during operation, and record it as the AGV speed interval. The detection range analysis method includes:

[0047] Respectively obtain the deceleration acceleration during emergency braking of the AGV, the deceleration acceleration during normal braking, and the minimum deceleration acceleration, and record them as V1, V2, and V3 respectively;

[0048] In the specific implementation process, by obtaining V1, V2, and V3, the different braking states of the AGV can be analyzed, which helps to obtain the area where the AGV can avoid obstacles by deceleration and the area where it needs to avoid obstacles by stopping at different running speeds, making the obstacle avoidance of the AGV during operation more accurate and efficient;

[0049] For any speed α within the AGV speed interval, start the AGV and adjust the speed of the AGV to speed α, and respectively obtain the distances traveled by the AGV when decelerated to a standstill by V1, V2, and V3, and record them as the emergency braking distance, the normal braking distance, and the minimum deceleration distance respectively; establish a plane rectangular coordinate system, and record it as the deceleration analysis coordinate system. Among them, the unit of the X-axis of the deceleration analysis coordinate system is m, and the unit of the Y-axis is m; respectively mark the points (XX1, 0), (XX2, 0), and (XX3, 0) on the positive half-axis of the deceleration analysis coordinate system, where XX1 is the emergency braking distance, XX2 is the normal braking distance, and XX3 is the minimum deceleration distance;

[0050] In the specific implementation process, for example, the deceleration analysis coordinate system obtained during a data processing is as Figure 3 shown. Among them, through data acquisition, the front detection width of the AGV is obtained as 1 meter, then the value of YY1 is 0.5; Figure 3Among them, rectangle JX1 is the emergency braking rectangle, rectangle JX2 is the normal braking rectangle, and rectangle JX3 is the maximum braking rectangle. Through analysis, it can be obtained that area QY1 is the normal braking area, area QY2 is the maximum braking area, and the deceleration division ratio is the ratio of the area of area QY2 to the area of area QY1;

[0051] In the front view of the AGV, the maximum length in the horizontal direction is denoted as the front detection width; the straight line formed by the coordinate origin and the point (XX1, 0) is taken as the length, and the straight line formed by the points (0, YY1) and (0, -YY1) is taken as the width to make a rectangle, which is denoted as the emergency braking rectangle, where YY1 is half of the front detection width;

[0052] Keep the side of the emergency braking rectangle that coincides with the Y-axis unchanged, and expand the emergency braking rectangle proportionally until the length of the emergency braking rectangle is XX2, and denote the emergency braking rectangle at this time as the normal braking rectangle; keep the side of the emergency braking rectangle that coincides with the Y-axis unchanged, and expand the emergency braking rectangle proportionally until the length of the emergency braking rectangle is XX3, and denote the emergency braking rectangle at this time as the maximum braking rectangle;

[0053] When the area of the region in the normal braking rectangle that does not coincide with the emergency braking rectangle is denoted as the normal braking area, and the area of the region in the maximum range rectangle that does not coincide with the normal braking rectangle is denoted as the maximum braking area; the ratio of the area of the normal braking area to the area of the emergency braking rectangle is denoted as the deceleration judgment ratio, and the ratio of the area of the maximum braking area to the area of the normal braking area is denoted as the deceleration division ratio;

[0054] In the specific implementation process, by obtaining the deceleration judgment ratio and the deceleration division ratio, the relationship between the three braking accelerations at speed α can be obtained. When both the deceleration division ratio and the deceleration division ratio are less than 1, it indicates that the deceleration path differences caused by the three brakings at speed α are relatively small; when both the deceleration division ratio and the deceleration division ratio are greater than or equal to 1, it indicates that the deceleration path differences caused by the three brakings at speed α are relatively large; when only one of the deceleration judgment ratio and the deceleration division ratio is greater than or equal to 1, it indicates that the deceleration path differences caused by the three brakings at speed α are relatively conventional. Therefore, the parking detection area and the deceleration detection area can be set according to the path differences caused by the three brakings of the AGV at speed α. In this embodiment, the parking detection area is the area where the AGV needs to stop and avoid, and the deceleration detection area is the area where the AGV needs to decelerate and avoid. At the same time, in this embodiment, the acceleration of the AGV during deceleration and avoidance in the deceleration detection area is analyzed later to ensure more accurate and efficient deceleration and avoidance;

[0055] When both the deceleration judgment ratio and the deceleration discrimination ratio are less than 1, the laser detection type of speed α is recorded as emergency braking detection, the parking detection area of speed α is set as the minimum parking area, and the deceleration detection area of speed α is set as the area in the maximum braking rectangle except the minimum parking area. Among them, the minimum parking area is obtained by keeping the side coinciding with the Y-axis of the emergency braking rectangle unchanged and reducing the emergency braking rectangle proportionally until the length of the emergency braking rectangle is 2 / XX1, and the corresponding rectangle area is obtained;

[0056] When both the deceleration judgment ratio and the deceleration discrimination ratio are greater than or equal to 1, the laser detection type of speed α is recorded as double deceleration braking detection, the parking detection area of speed α is set as the area where the emergency braking rectangle is located, and the deceleration detection area of speed α is set as the area where the normal braking area and the maximum braking area are located;

[0057] When only one of the deceleration judgment ratio and the deceleration discrimination ratio is greater than or equal to 1, the laser detection type of speed α is recorded as single deceleration braking detection, the parking detection area of speed α is set as the area where the emergency braking rectangle and the normal braking area are located, and the deceleration detection area of speed α is set as the area where the maximum braking area is located;

[0058] Obtain the parking detection area and the deceleration detection area corresponding to all speeds within the AGV speed range.

[0059] The deceleration area analysis module is used to, when there is an object in the deceleration detection area, analyze the deceleration detection area based on the deceleration judgment method using laser detection, obtain the real-time position of the object in the deceleration detection area based on laser detection, and obtain multiple deceleration judgment criteria;

[0060] The deceleration area analysis module includes a deceleration judgment unit, and the deceleration judgment unit is configured with a deceleration judgment strategy. The deceleration judgment strategy includes: for any speed α in any AGV speed range, obtain the historical detection record of the laser in the AGV and the historical deceleration record of the AGV when the AGV runs at speed α, and record them as the running detection record α and the running deceleration record α; when any object β is detected in the deceleration detection area of speed α in the running detection record α, record the time when the object β is detected in the running detection record α as the object detection time β, and record the time when the AGV starts to decelerate triggered by detecting the object β in the running deceleration record α as the object deceleration time β;

[0061] Based on the running detection record α, respectively obtain the straight-line distance between the object β and the AGV at the object deceleration time β and the object detection time β, and record them as the deceleration response distance and the detection response distance respectively; record the acceleration of the AGV at the object deceleration time β in the historical running data of the AGV as the normal acceleration;

[0062] Obtain the normal acceleration, deceleration response distance, and detection response distance when detecting all objects in the deceleration detection area with speed α in the running detection record α; use the detection magnification algorithm to obtain the detection deceleration magnification corresponding to speed α, and the detection magnification algorithm includes: where F is the detection deceleration magnification, q is the number of objects in the deceleration detection area with speed α detected in the running detection record α, and L i and D i are respectively the deceleration response distance and the detection response distance of the i-th object in the deceleration detection area with speed α detected in the running detection record α;

[0063] In a specific implementation process, for example, in a data processing, the number of objects in the deceleration detection area with speed α detected in the obtained running detection record α is 3, and the deceleration response distances and the detection response distances are 7 and 10, 5 and 8, and 6 and 9 respectively. Then, through calculation, the detection deceleration magnification is 1.51; by obtaining the detection deceleration magnification, the magnification by which the acceleration should be increased when the AGV decelerates and avoids collision at speed α can be obtained, so as to prevent the inability to avoid in time due to small acceleration during actual avoidance, resulting in a collision accident;

[0064] Obtain the detection deceleration magnification corresponding to all speeds in the AGV speed range.

[0065] The safety protection module is used to perform safety protection on the AGV during AGV operation based on the parking detection area, the deceleration detection area, and the deceleration judgment criteria for each deceleration detection area; the safety protection module includes an AGV protection unit, and the AGV protection unit is configured with an AGV protection strategy, and the AGV protection strategy includes:

[0066] When the AGV is running, coincide the real-time position and the operation direction of the AGV with the coordinate origin and the positive half-axis of the X-axis in the deceleration analysis coordinate system respectively; record the real-time speed of the AGV as speed γ, and use laser detection to perform real-time detection within the area corresponding to the maximum braking rectangle of speed γ;

[0067] When there is an object in the parking detection area corresponding to speed γ, decelerate the AGV at V1 and perform steering processing, where the steering processing includes: when the object in the parking detection area is in the first quadrant of the deceleration analysis coordinate, control the AGV to turn to the right; when the object in the parking detection area is in the fourth quadrant of the deceleration analysis coordinate, control the AGV to turn to the left; when the object in the parking detection area is on the positive half-axis of the X-axis of the deceleration analysis coordinate, control the AGV to turn to the direction of the quadrant with the least number of objects in the first quadrant and the fourth quadrant of the deceleration analysis coordinate;

[0068] When there is an object in the deceleration detection area corresponding to the speed γ, when the object is detected by the laser, the AGV is decelerated with an acceleration δ, where δ is the product of the normal acceleration of the speed γ and the detection deceleration magnification of the speed γ;

[0069] In the specific implementation process, for example, during a data analysis, the normal acceleration of the speed γ is 2 m / s 2 , and the detection deceleration magnification of the speed γ is 1.5. Then, through calculation, it can be obtained that when the object is detected by the laser at the speed γ, the AGV should decelerate with an acceleration of 3 m / s 2 .

[0070] Embodiment 2, please refer to Figure 2 As shown, the present application also provides a safety protection method in AGV operation, including the following steps:

[0071] Step S1, obtain the AGV speed interval based on the running speed during AGV operation; use the detection range analysis method to obtain the laser detection type when the speed of the AGV is each speed within the AGV speed interval, and obtain the deceleration detection area and the stop detection area corresponding to each laser detection type;

[0072] Obtain the interval that the running speed during AGV operation can reach, and denote it as the AGV speed interval. The detection range analysis method includes:

[0073] Step S101, respectively obtain the deceleration acceleration during AGV emergency braking, the deceleration acceleration during normal braking, and the minimum deceleration acceleration, and denote them as V1, V2, and V3 respectively;

[0074] Step S102, for any speed α within the AGV speed interval, start the AGV and adjust the speed of the AGV to the speed α, and respectively obtain the distances traveled by the AGV when it is decelerated to a standstill by V1, V2, and V3, and denote them as the emergency braking distance, the normal braking distance, and the minimum deceleration distance respectively; establish a plane rectangular coordinate system, and denote it as the deceleration analysis coordinate system, where the unit of the X-axis of the deceleration analysis coordinate system is m, and the unit of the Y-axis is m; respectively mark the points (XX1, 0), (XX2, 0), and (XX3, 0) on the positive half-axis of the deceleration analysis coordinate system, where XX1 is the emergency braking distance, XX2 is the normal braking distance, and XX3 is the minimum deceleration distance;

[0075] Step S103, denote the maximum length occupied by the horizontal direction in the front view of the AGV as the front detection width; make a rectangle with the line connecting the coordinate origin and the point (XX1, 0) as the length and the line connecting the points (0, YY1) and (0, -YY1) as the width, and denote it as the emergency braking rectangle, where YY1 is half of the front detection width;

[0076] Step S104, keep the side of the emergency braking rectangle that coincides with the Y-axis stationary, and proportionally expand the emergency braking rectangle until the length of the emergency braking rectangle is XX2, and record the emergency braking rectangle at this time as the normal braking rectangle; keep the side of the emergency braking rectangle that coincides with the Y-axis stationary, and proportionally expand the emergency braking rectangle until the length of the emergency braking rectangle is XX3, and record the emergency braking rectangle at this time as the maximum braking rectangle;

[0077] Step S105, when the area of the region in the normal braking rectangle that does not coincide with the emergency braking rectangle is recorded as the normal braking area, and the area of the region in the maximum range rectangle that does not coincide with the normal braking rectangle is recorded as the maximum braking area; record the ratio of the area of the normal braking area to the area of the emergency braking rectangle as the deceleration judgment ratio, and record the ratio of the area of the maximum braking area to the area of the normal braking area as the deceleration discrimination ratio;

[0078] Step S106, when both the deceleration judgment ratio and the deceleration discrimination ratio are less than 1, record the laser detection type of speed α as emergency braking detection, set the parking detection area of speed α as the minimum parking area, and set the deceleration detection area of speed α as the area in the maximum braking rectangle except for the minimum parking area, where the minimum parking area is the area where the rectangle is located when keeping the side of the emergency braking rectangle that coincides with the Y-axis stationary and proportionally reducing the emergency braking rectangle until the length of the emergency braking rectangle is 2 / XX1;

[0079] Step S107, when both the deceleration judgment ratio and the deceleration discrimination ratio are greater than or equal to 1, record the laser detection type of speed α as double deceleration braking detection, set the parking detection area of speed α as the area where the emergency braking rectangle is located, and set the deceleration detection area of speed α as the area where the normal braking area and the maximum braking area are located;

[0080] Step S108, when only one of the deceleration judgment ratio and the deceleration discrimination ratio is greater than or equal to 1, record the laser detection type of speed α as single deceleration braking detection, set the parking detection area of speed α as the area where the emergency braking rectangle and the normal braking area are located, and set the deceleration detection area of speed α as the area where the maximum braking area is located;

[0081] Step S109, obtain the parking detection area and the deceleration detection area corresponding to all speeds within the AGV speed range.

[0082] Step S2, obtain the historical detection records of the laser in the AGV and the historical deceleration records of the AGV at each speed within the AGV speed range, and obtain the detection deceleration magnification corresponding to each speed within the AGV speed range based on the historical detection records and the historical deceleration records;

[0083] Step S2 includes: Step S201, for any speed α in any AGV speed range, obtain the historical detection record of the laser in the AGV and the historical deceleration record of the AGV when the AGV runs at speed α, and denote them as the running detection record α and the running deceleration record α; when an object β is detected in the deceleration detection area of speed α in the running detection record α, record the time when the object β is detected in the running detection record α as the object detection time β, and record the time when the AGV starts to decelerate triggered by detecting the object β in the running deceleration record α as the object deceleration time β;

[0084] Step S202, respectively obtain the straight-line distance between the object β and the AGV at the object deceleration time β and the object detection time β based on the running detection record α, and denote them as the deceleration response distance and the detection response distance respectively; denote the acceleration of the AGV at the object deceleration time β in the historical running data of the AGV as the normal acceleration;

[0085] Step S203, obtain the normal acceleration, deceleration response distance, and detection response distance when all objects in the deceleration detection area of speed α are detected in the running detection record α; use the detection magnification algorithm to obtain the detection deceleration magnification corresponding to speed α, and the detection magnification algorithm includes: where F is the detection deceleration magnification, q is the number of objects in the deceleration detection area of speed α detected in the running detection record α, and Li and Di are the deceleration response distance and the detection response distance of the i-th object in the deceleration detection area of speed α detected in the running detection record α respectively;

[0086] Step S204, obtain the detection deceleration magnification corresponding to all speeds in the AGV speed range.

[0087] Step S3, based on the parking detection area, deceleration detection area, and the detection deceleration magnification corresponding to each speed in the AGV speed range, perform safety protection on the AGV during AGV operation.

[0088] Step S3 includes: Step S301, when the AGV runs, coincide the real-time position and the operation direction of the AGV with the coordinate origin and the positive half-axis of the X-axis in the deceleration analysis coordinate system respectively; denote the real-time speed of the AGV as speed γ, and perform real-time detection on the area corresponding to the maximum braking rectangle of speed γ using laser detection;

[0089] Step S302, when there is an object in the parking detection area corresponding to the speed γ, decelerate the AGV at V1 and perform a steering process. The steering process includes: when the object in the parking detection area is in the first quadrant of the deceleration analysis coordinate, control the AGV to turn to the right; when the object in the parking detection area is in the fourth quadrant of the deceleration analysis coordinate, control the AGV to turn to the left; when the object in the parking detection area is on the positive x-axis of the deceleration analysis coordinate, control the AGV to turn to the direction of the quadrant with the least number of objects in the first and fourth quadrants of the deceleration analysis coordinate.

[0090] Step S303, when there is an object in the deceleration detection area corresponding to the speed γ, decelerate the AGV at an acceleration δ when the object is detected by the laser, where δ is the product of the normal acceleration of the speed γ and the detection deceleration magnification of the speed γ.

[0091] Example 3, please refer to Figure 4 as shown in Figure 4 illustrates a schematic structural diagram of an electronic device. The electronic device may include: a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete mutual communication through the communication bus. The memory stores computer-readable instructions. The processor can call the instructions in the memory. When the computer-readable instructions are executed by the processor, the steps in a safety protection method in an AGV operation are run to implement the following functions: First, obtain the AGV speed range based on the running speed during AGV operation; use the detection range analysis method to obtain the laser detection type when the speed of the AGV is at each speed within the AGV speed range, and obtain the deceleration detection area and the parking detection area corresponding to each laser detection type; then obtain the historical detection record of the laser in the AGV and the historical deceleration record of the AGV at each speed in the AGV speed range, and obtain the detection deceleration magnification corresponding to each speed in the AGV speed range based on the historical detection record and the historical deceleration record; finally, based on the parking detection area, the deceleration detection area, and the detection deceleration magnification corresponding to each speed within the AGV speed range, perform safety protection on the AGV during AGV operation.

[0092] In addition, when the logical instructions in the above-mentioned memory are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0093] Embodiment 4, this application also provides a computer-readable storage medium. This application provides a storage medium on which a computer program is stored. When the computer program is executed by a processor, it runs the steps in a safety protection method in an AGV operation as described above to achieve the following functions: First, obtain the AGV speed range based on the running speed during AGV operation; use the detection range analysis method to obtain the laser detection types when the AGV speed is at each speed within the AGV speed range, and obtain the deceleration detection area and the stop detection area corresponding to each laser detection type; then obtain the historical detection records of the laser in the AGV and the historical deceleration records of the AGV at each speed in the AGV speed range, and obtain the detection deceleration ratio corresponding to each speed in the AGV speed range based on the historical detection records and the historical deceleration records; finally, based on the stop detection area, the deceleration detection area, and the detection deceleration ratio corresponding to each speed within the AGV speed range, perform safety protection on the AGV during AGV operation.

[0094] Through the description of the above embodiments, the embodiments of the present invention can be provided as a method, a system, or a computer program product. Based on such an understanding, the above technical solution, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disks, optical discs, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments.

[0095] In the embodiments provided in the present application, it should be understood that the disclosed system or method can be implemented in other ways. The embodiments described above are merely illustrative. For example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation. For another example, multiple modules or units can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection between each other can be through some communication interfaces. The indirect coupling or communication connection of systems, modules, and units can be electrical, mechanical, or other forms.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A safety protection method in AGV operation, characterized in that, The method includes the following steps: Obtain the AGV speed range based on the running speed of the AGV during operation; use the detection range analysis method to obtain the laser detection type when the speed of the AGV is at each speed within the AGV speed range, and obtain the deceleration detection area and the stop detection area corresponding to each laser detection type; Obtain the historical detection records of the laser in the AGV and the historical deceleration records of the AGV at each speed within the AGV speed range, and obtain the detection deceleration magnification corresponding to each speed within the AGV speed range based on the historical detection records and the historical deceleration records; Based on the stop detection area, the deceleration detection area, and the detection deceleration magnification corresponding to each speed within the AGV speed range, perform safety protection on the AGV during operation.

2. The safety protection method in an AGV operation according to claim 1, wherein, Obtain the range that the running speed of the AGV can reach during operation, and denote it as the AGV speed range. The detection range analysis method includes: Respectively obtain the deceleration acceleration during emergency braking of the AGV, the deceleration acceleration during normal braking of the AGV, and the minimum deceleration acceleration, and denote them as V1, V2, and V3 respectively; For any speed α within the AGV speed range, start the AGV and adjust the speed of the AGV to speed α, and respectively obtain the distances traveled by the AGV when it is decelerated to a standstill by V1, V2, and V3, and denote them as the emergency braking distance, the normal braking distance, and the minimum deceleration distance respectively; establish a plane rectangular coordinate system, and denote it as the deceleration analysis coordinate system, where the unit of the X-axis of the deceleration analysis coordinate system is m, and the unit of the Y-axis is m; respectively mark the points (XX1, 0), (XX2, 0), and (XX3, 0) on the positive half-axis of the deceleration analysis coordinate system, where XX1 is the emergency braking distance, XX2 is the normal braking distance, and XX3 is the minimum deceleration distance.

3. The safety protection method in AGV operation according to claim 2, wherein The detection range analysis method further includes: Denote the maximum length occupied by the horizontal direction in the front view of the AGV as the front detection width; make a rectangle with the straight line formed by the coordinate origin and the point (XX1, 0) as the length and the straight line formed by the points (0, YY1) and (0, -YY1) as the width, and denote it as the emergency braking rectangle, where YY1 is half of the front detection width; Keep the side of the emergency braking rectangle that coincides with the Y-axis unchanged, and expand the emergency braking rectangle proportionally until the length of the emergency braking rectangle is XX2, and denote the emergency braking rectangle at this time as the normal braking rectangle; keep the side of the emergency braking rectangle that coincides with the Y-axis unchanged, and expand the emergency braking rectangle proportionally until the length of the emergency braking rectangle is XX3, and denote the emergency braking rectangle at this time as the maximum braking rectangle.

4. A safety protection method in AGV operation according to claim 3, characterized in that, The detection range analysis method further includes: When the area of the region in the normal braking rectangle that does not coincide with the emergency braking rectangle is denoted as the normal braking area, and the area of the region in the maximum range rectangle that does not coincide with the normal braking rectangle is denoted as the maximum braking area; denote the ratio of the area of the normal braking area to the area of the emergency braking rectangle as the deceleration judgment ratio, and denote the ratio of the area of the maximum braking area to the area of the normal braking area as the deceleration discrimination ratio; When both the deceleration judgment ratio and the deceleration discrimination ratio are less than 1, the laser detection type of speed α is recorded as emergency braking detection, the parking detection area of speed α is set as the minimum parking area, and the deceleration detection area of speed α is set as the area other than the minimum parking area in the maximum braking rectangle. Among them, the minimum parking area is the area where the side of the emergency braking rectangle that coincides with the Y-axis remains unchanged, and the emergency braking rectangle is proportionally reduced until the length of the emergency braking rectangle is 2 / XX1. When both the deceleration judgment ratio and the deceleration discrimination ratio are greater than or equal to 1, the laser detection type of speed α is recorded as double deceleration braking detection, the parking detection area of speed α is set as the area where the emergency braking rectangle is located, and the deceleration detection area of speed α is set as the area where the normal braking area and the maximum braking area are located.

5. The safety protection method in an AGV operation according to claim 4, characterized in that, The detection range analysis method also includes: When only one of the deceleration judgment ratio and the deceleration discrimination ratio is greater than or equal to 1, the laser detection type of speed α is recorded as single deceleration braking detection, the parking detection area of speed α is set as the area where the emergency braking rectangle and the normal braking area are located, and the deceleration detection area of speed α is set as the area where the maximum braking area is located. Obtain the parking detection area and the deceleration detection area corresponding to all speeds within the AGV speed range.

6. The safety protection method in the AGV operation according to claim 1, characterized in that, Obtaining the detection deceleration ratio corresponding to each speed in the AGV speed range based on the historical detection record and the historical deceleration record includes: For any speed α in any AGV speed range, obtain the historical detection record of the laser in the AGV and the historical deceleration record of the AGV when the AGV runs at speed α, and record them as the running detection record α and the running deceleration record α; when any object β is detected in the deceleration detection area of speed α in the running detection record α, record the time when the object β is detected in the running detection record α as the object detection time β, and record the time when the AGV starts to decelerate triggered by detecting the object β in the running deceleration record α as the object deceleration time β. Based on the running detection record α, obtain the straight-line distance between the object β and the AGV at the object deceleration time β and the object detection time β respectively, and record them as the deceleration response distance and the detection response distance; record the acceleration of the AGV at the object deceleration time β in the historical running data of the AGV as the normal acceleration.

7. The safety protection method in an AGV operation according to claim 6, wherein Obtaining the detection deceleration ratio corresponding to each speed in the AGV speed range based on the historical detection record and the historical deceleration record also includes: Obtain the normal acceleration, deceleration response distance, and detection response distance when detecting all objects in the deceleration detection area with speed α in the running detection record α; use the detection magnification algorithm to obtain the detection deceleration magnification corresponding to speed α, and the detection magnification algorithm includes: where F is the detection deceleration magnification, q is the number of objects in the deceleration detection area with speed α detected in the running detection record α, and Li and Di are the deceleration response distance and detection response distance of the i-th object in the deceleration detection area with speed α detected in the running detection record α, respectively; Obtain the detection deceleration ratio corresponding to all speeds in the AGV speed range.

8. A safety protection method in AGV operation according to claim 1, characterized in that, Based on the parking detection area, the deceleration detection area, and the detection deceleration ratio corresponding to each speed within the AGV speed range, perform safety protection on the AGV during AGV operation, including: When the AGV is running, align the real-time position and the operation direction of the AGV with the coordinate origin and the positive half-axis of the X-axis in the deceleration analysis coordinate system respectively; record the real-time speed of the AGV as speed γ, and use laser detection to perform real-time detection on the area corresponding to the maximum braking rectangle of speed γ.

9. A safety protection method in an AGV operation according to claim 1, characterized in that Based on the parking detection area, the deceleration detection area, and the detection deceleration magnification corresponding to each speed within the AGV speed range, the safety protection of the AGV during operation also includes: When there is an object in the parking detection area corresponding to speed γ, the AGV is decelerated at V1 and steering processing is performed. The steering processing includes: when the object in the parking detection area is in the first quadrant of the deceleration analysis coordinate, controlling the AGV to turn to the right; when the object in the parking detection area is in the fourth quadrant of the deceleration analysis coordinate, controlling the AGV to turn to the left; when the object in the parking detection area is on the positive X-axis of the deceleration analysis coordinate, controlling the AGV to turn in the direction of the quadrant with the least number of objects in the first and fourth quadrants of the deceleration analysis coordinate; When there is an object in the deceleration detection area corresponding to speed γ, the AGV is decelerated at an acceleration δ when the object is detected by the laser, where δ is the product of the normal acceleration of speed γ and the detection deceleration magnification of speed γ.

10. A safety protection system in AGV operation, which is used to implement the safety protection method in AGV operation described in any one of claims 1-9, and is characterized in that, It includes a laser detection module, a deceleration area analysis module, and a safety protection module; The laser detection module is used to obtain multiple speed ranges based on the running speed during AGV operation; use the detection range analysis method to obtain the laser detection type when the AGV speed is in each speed range, and obtain the deceleration detection area and the parking detection area corresponding to each laser detection type; The deceleration area analysis module is used to, when there is an object in the deceleration detection area, analyze the deceleration detection area using the deceleration judgment method based on laser detection, obtain the real-time position of the object in the deceleration detection area based on laser detection, and obtain multiple deceleration judgment criteria; The safety protection module is used to perform safety protection on the AGV during AGV operation based on the parking detection area, the deceleration detection area, and the deceleration judgment criteria for each deceleration detection area.

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