AGV safety control method and AGV vehicle

Abstract

The invention discloses an AGV safety control method and an AGV vehicle. The method comprises the steps that a first control system sends a control instruction to an actuator; the actuator controls an execution mechanism to execute the control instruction; the position sensor collects position data of operation of the execution mechanism and sends the position data to the second control system; the second control system calculates motion data based on the position data and judges the motion data; the motion data comprises at least one of a driving distance, a motion speed, a speed deviation, a position deviation and a distance deviation; and when the second control system judges that one of the motion data exceeds the AGV safety limit, the actuator is controlled to stop execution. Based on the position sensor, the driving safety after the personnel detection device is closed is guaranteed through safety closed-loop control, the lifting safety is guaranteed through the safety closed-loop control, the control safety level can reach the PLd level, and the safety of personnel and goods is greatly guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial vehicles, and particularly to an AGV safety control method and an AGV vehicle. Background Art

[0002] During the operation of an AGV, CE certification is required. Among them, in ISO 3691-4 4.2, it is required that the vehicle should be equipped with a braking system and operate under power interruption; this braking system can cut off the power supply and be automatically activated when the speed or cornering gets out of control to prevent the danger of hitting people, and the safety level requirement is PLd, that is, the AGV should have a braking safety function during driving or lifting and reach the corresponding safety level. In addition, in ISO 3691-4 4.8.2.3, it is required that when the vehicle needs to temporarily turn off the personnel detection function (in some special application scenarios, due to the limitations of the on-site AGV operating environment and working conditions, the AGV needs to briefly turn off the personnel detection to ensure the normal operation of the AGV), the vehicle speed should be controlled within the specified vehicle speed, and the personnel detection function should be turned off as late as possible to ensure the safety of personnel detection and prevent the danger of hitting people, and the safety level requirement is PLd.

[0003] The Chinese patent application "A method for detecting the driving safety of a parking robot, CN202010011620.0" only mentions how to detect safety during driving and does not mention the safety detection method after the safety detection device is turned off.

[0004] The Chinese patent application "An AGV lifting high-precision stop position device and its control method, CN202210090888.7" uses a single height measurement device to confirm the height of the forklift, and only has a simple height closed-loop control without a safety closed-loop detection. Summary of the Invention

[0005] The main purpose of the present invention is to overcome the above-mentioned defects in the prior art, and propose an AGV safety control method and an AGV vehicle. Based on a position sensor, the driving safety after the personnel detection device is turned off is ensured through safety closed-loop control, and the lifting safety is ensured through safety closed-loop control, so that the control safety level can reach the PLd level, greatly ensuring the safety of personnel and goods.

[0006] The present invention adopts the following technical solutions:

[0007] On the one hand, an AGV safety control method includes:

[0008] The first control system sends a control instruction to the actuator;

[0009] The actuator controls the execution mechanism to execute the control instruction;

[0010] The position sensor collects the position data of the operation of the actuator and sends it to the second control system;

[0011] The second control system calculates and judges the motion data based on the position data; the motion data includes at least one of travel distance, motion speed, speed deviation, position deviation, and distance deviation;

[0012] When the second control system determines that one of the motion data exceeds the AGV safety limit, it controls the actuator to stop execution.

[0013] Preferably, the actuator is a travel actuator; the actuator mechanism is a travel actuator mechanism; the position sensor is a travel position sensor; the control instruction includes a travel control instruction;

[0014] Before the actuator controls the actuator mechanism to execute the control instruction, it further includes:

[0015] The first control system sends a personnel detection shutdown instruction to the second control system; after receiving the personnel detection shutdown instruction, the second control system starts to monitor the position data sent by the position sensor.

[0016] Preferably, the position sensor includes one; the motion data includes travel distance and / or motion speed; the travel distance is equal to the difference between the current position collected by the position sensor and the position when the travel control instruction is received; the motion speed is equal to the quotient of the difference between the position at the current moment and the previous moment collected by the position sensor and the time difference.

[0017] Preferably, the position sensor includes two, namely the first travel position sensor and the second travel position sensor; the motion data includes at least one of travel distance, motion speed, and speed deviation; the travel distance is equal to the difference between the current position collected by the first travel position sensor / second travel position sensor and the position when the travel control instruction is received; the motion speed is equal to the quotient of the difference between the position at the current moment and the previous moment collected by the first travel position sensor / second travel position sensor and the time difference; the speed deviation is equal to the absolute value of the difference between the motion speed of the first travel position sensor and the motion speed of the second travel position sensor.

[0018] Preferably, the actuator is a lifting actuator; the actuator mechanism is a lifting actuator mechanism; the position sensor is a lifting mechanism position sensor; the control instruction includes a lifting control instruction;

[0019] Before the actuator controls the actuator mechanism to execute the control instruction, it further includes:

[0020] The first control system sends a control instruction to the second control system; after receiving the control instruction, the second control system starts the position data sent by the monitoring position sensor.

[0021] Preferably, the position sensor includes one; the motion data includes a position deviation and / or a motion speed; the position deviation is equal to the difference between the target position and the current position collected by the position sensor; the motion speed is equal to the quotient of the difference between the current position and the previous position collected by the position sensor and the time difference.

[0022] Preferably, the position sensor includes two, namely the first lifting mechanism position sensor and the second lifting mechanism position sensor; the motion data includes at least one of a position deviation, a motion speed, and a distance deviation; the position deviation is equal to the difference between the target position and the current position collected by the first lifting mechanism position sensor / second lifting mechanism position sensor; the motion speed is equal to the quotient of the difference between the current position and the previous position collected by the first lifting mechanism position sensor / second lifting mechanism position sensor and the time difference, or the motion speed is equal to the average value of the motion speed of the first lifting mechanism position sensor and the motion speed of the second lifting mechanism position sensor; the distance deviation is equal to the difference between the current position collected by the first lifting mechanism position sensor and the current position collected by the second lifting mechanism position sensor.

[0023] Preferably, the AGV safety control method further includes:

[0024] The position sensor collects the position data of the operation of the actuator and sends it to the first control system;

[0025] The first control system calculates the motion data based on the position data and makes a judgment;

[0026] When the first control system determines that one of the motion data exceeds the AGV safety limit, it stops sending the control instruction, the actuator controls the actuator to stop operating, and reports a fault. After the second controller detects the fault, it controls the actuator to stop executing.

[0027] On the other hand, an AGV vehicle includes: a first control system, a second control system, an actuator, an actuator mechanism, and a position sensor;

[0028] The first control system is configured to send a control instruction to the actuator;

[0029] The actuator is configured to control the actuator mechanism to execute the control instruction;

[0030] The position sensor is configured to collect the position data of the operation of the actuator mechanism and send it to the second control system;

[0031] The second control system is configured to calculate motion data based on the position data and make a judgment; the motion data includes at least one of a traveling distance, a motion speed, a speed deviation, a position deviation, and a distance deviation; when the second control system determines that one of the motion data exceeds the AGV safety limit, it controls the actuator to stop executing.

[0032] Preferably, the position sensor is further configured to collect the position data of the operation of the actuator and send it to the first control system; the first control system is further configured to calculate motion data based on the position data and make a judgment; when the first control system determines that one of the motion data exceeds the AGV safety limit, it stops sending control instructions, the actuator controls the actuator to stop operating, and reports a fault, and after the second controller detects the fault, it controls the actuator to stop executing.

[0033] As can be seen from the above description of the present invention, compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The present invention uses two safety closed-loop controls, namely a traveling speed safety detection closed loop and a traveling distance safety detection closed loop, to control the traveling safety after the personnel detection device is turned off, so that the safety level of this control can reach the PLd level, greatly ensuring the safety of personnel and goods;

[0035] (2) The present invention uses two safety closed-loop controls, namely a lifting position safety detection closed loop and a lifting speed safety detection closed loop, to detect the control of the lifting system, so that the safety level of the control of the lifting system can reach the PLd level, greatly ensuring the safety of personnel and goods;

[0036] (3) The present invention uses two traveling position sensors to detect the position of the traveling actuator mechanism, and the redundant detection method makes the traveling detection safer and more reliable;

[0037] (4) The present invention uses two lifting mechanism position sensors to detect the position of the lifting actuator mechanism, and the redundant detection method makes the traveling detection system safer and more reliable. Description of the Drawings

[0038] Figure 1 It is the basic flowchart of the AGV safety control method of the first embodiment;

[0039] Figure 2 It is the preferred flowchart of the AGV safety control method of the first embodiment;

[0040] Figure 3 It is the control flowchart block diagram including two traveling position sensors of the first embodiment;

[0041] Figure 4 This is the detailed control flowchart of the first embodiment including two travel position sensors;

[0042] Figure 5 This is the schematic diagram of the safety level calculation result of the second control system (AGV safety control system) in the first embodiment;

[0043] Figure 6 This is the basic flowchart of the AGV safety control method in the second embodiment;

[0044] Figure 7 This is the preferred flowchart of the AGV safety control method in the second embodiment;

[0045] Figure 8 This is the control flowchart block diagram of the second embodiment including two travel position sensors;

[0046] Figure 9 This is the detailed control flowchart of the second embodiment including two travel position sensors;

[0047] Figure 10 This is the schematic diagram of the safety level calculation result of the second control system (AGV safety control system) in the second embodiment. Specific embodiments

[0048] The present invention will be further described below through specific embodiments.

[0049] Embodiment 1

[0050] The AGV safety control method of this embodiment is applied to the scenario of safety control during the AGV driving process after the personnel detection function is turned off.

[0051] See Figure 1 As shown, an AGV safety control method in this embodiment includes:

[0052] S101, the first control system sends a driving control instruction to the driving actuator and sends a personnel detection off instruction to the second control system;

[0053] S102, the driving actuator controls the driving execution mechanism to execute the driving control instruction;

[0054] S103, the travel position sensor collects the position data of the operation of the driving execution mechanism and sends it to the second control system;

[0055] S104, the second control system calculates the motion data based on the position data and makes a judgment; the motion data includes at least one of the travel distance, motion speed, and speed deviation;

[0056] S105. When the second control system determines that one of the motion data exceeds the AGV safety limit, it controls the driving actuator to stop execution.

[0057] See Figure 2 As shown, in this embodiment, in order to achieve redundant control and ensure control safety, the position data collected by the position sensor can also be sent to the first control system, and the first control system also performs detection and control, specifically including:

[0058] The driving position sensor collects the position data of the operation of the driving actuator mechanism and sends it to the first control system;

[0059] The first control system calculates the motion data based on the position data and makes a judgment;

[0060] When the first control system determines that one of the motion data exceeds the AGV safety limit, it stops sending the driving control instruction, the driving actuator controls the driving actuator mechanism to stop operating, and reports a fault. After the second controller detects the fault, it controls the driving actuator to stop execution.

[0061] In this embodiment, the first control system is the AGV driving control system; the second control system is the AGV safety control system.

[0062] Specifically, the driving position sensor includes one or two.

[0063] When the driving position sensor is one, the motion data includes the driving distance and / or the motion speed; the driving distance is equal to the difference between the current position collected by the position sensor and the position when the driving control instruction is received; the motion speed is equal to the quotient of the difference between the position at the current moment and the position at the previous moment collected by the position sensor and the time difference.

[0064] See Figure 3 As shown, in this embodiment, two driving position sensors are used to detect the position of the driving actuator mechanism. The redundant detection method makes the driving detection safer and more reliable. The two driving position sensors are the first driving position sensor and the second driving position sensor respectively, and can be installed on the bearing of the driving actuator mechanism such as a motor. The motion data includes at least one of the driving distance, the motion speed, and the speed deviation; the driving distance is equal to the difference between the current position collected by the first driving position sensor / second driving position sensor and the position when the driving control instruction is received; the motion speed is equal to the quotient of the difference between the position at the current moment and the position at the previous moment collected by the first driving position sensor / second driving position sensor and the time difference; the speed deviation is equal to the absolute value of the difference between the motion speed of the first driving position sensor and the motion speed of the second driving position sensor.

[0065] See Figure 4 as shown below. The specific control process is as follows.

[0066] 1. When the AGV enters the special operation condition, the AGV driving control system will turn off the personnel detection device and issue a driving control instruction (the driving speed is carried in the driving control instruction) to the driving actuator. At this time, the AGV driving control system and the AGV safety control system will monitor the speed and driving distance of the current driving mechanism according to the feedback data of the first driving position sensor and the second driving position sensor, and perform the control of the driving speed safety detection closed-loop and the driving safety detection safety closed-loop.

[0067] 2. When the AGV enters the special operation condition, the AGV driving control system will turn off the personnel detection device and issue a driving control instruction to the driving actuator. The AGV safety control system and the AGV driving control system will simultaneously start the safety function detection.

[0068] 1) Driving distance safety detection closed-loop. After the personnel detection device is turned off, the maximum allowable driving distance value is Dsmax. When the driving actuator receives the driving control instruction, the AGV driving control system reads the data of the first driving position sensor to obtain the current position Dc1, and the AGV safety control system reads the data of the second driving position sensor to obtain the current position Dc2. The driving actuator enables the driving mechanism to start moving. The AGV driving control system reads the data of the first driving position sensor in real time to obtain the current position Ds1, and the AGV safety control system reads the data of the second driving position sensor in real time to obtain the current position Ds2, so as to obtain the vehicle's traveled distance values Da1 and Da2:

[0069] Da1 = Ds1 – Dc1;

[0070] Da2 = Ds2 – Dc2;

[0071] a. Safety control channel 1: The AGV driving control system monitors the driving distance Da1 of the vehicle after the personnel detection device is turned off in real time. Once it is found that Da1 is greater than or equal to Dsmax, the AGV driving control system stops sending the driving control instruction, the driving actuator immediately locks, the AGV reports a fault, and the AGV safety control system detects the fault of the AGV driving control system and immediately cuts off the power supply of the driving actuator to prevent continued movement from causing harm to personnel or goods;

[0072] b. Safety control channel 2: The AGV safety control system monitors the driving distance Da2 of the vehicle after the personnel detection device is turned off in real time. Once it is found that Da2 is greater than Dsmax, the AGV safety control system immediately cuts off the power supply of the driving actuator, and the AGV reports a fault to prevent continued movement from causing harm to personnel or goods.

[0073] 2) Closed-loop safety detection of driving speed. The maximum allowable driving speed value is Vsmax after the personnel detection device is closed, and the safety speed deviation value is Vv. When the driving actuator receives the driving control instruction and enables the driving actuator to start moving, the AGV safety control system starts to read the data of the first driving position sensor and the second driving position sensor in real time; the position data Dcp1 of the driving mechanism position sensor 1 at the previous moment, the time is Tp; the current position data Dc1, the time is T; the position data Dcp2 of the driving mechanism position sensor 2 at the previous moment, the time is Tp; the current position data Dc2, the time is T; thus, the actual movement speeds Va1 and Va2 of the driving mechanism can be obtained.

[0074] Va1 = (Dc1 - Dcp1) / (T - Tp)

[0075] Va2 = (Dc2 - Dcp2) / (T - Tp)

[0076] a. The AGV safety control system compares Va1 and Va2 in real time. If the absolute value of Va1 - Va2 (meeting the requirements of AGV forward and backward movement) is greater than the preset deviation Vv, the AGV safety control system determines that the difference between the two speed data is too large, immediately cuts off the power supply of the driving actuator, and stops the movement of the driving actuator to prevent continued movement from causing harm to personnel or goods;

[0077] b. The AGV safety control system compares Va1 with Vsmax and Va2 with Vsmax in real time. Once it is found that Va1 or Va2 is greater than or equal to Vsmax, the AGV safety system determines that the vehicle driving speed exceeds the safety setting value, immediately cuts off the power supply of the driving actuator, and stops the movement of the driving actuator to prevent continued movement from causing harm to personnel or goods.

[0078] See Figure 5 As shown, in this embodiment, based on the safety closed-loop control function of the driving safety control system, calculations are performed on the platform, and the safety level can reach PLd.

[0079] The following will take specific detection data as an example to illustrate safety control.

[0080] In this embodiment, the AGV driving control system is the AGV host computer, the AGV safety control system is the safety PLC controller, the driving position sensor can be an incremental encoder or a Hall speed sensor, the driving actuator is the driving servo controller, and the driving actuator is the driving motor and wheels. When the AGV drives into a special operation condition, the AGV driving control system will close the personnel detection device and issue a driving control instruction to the driving actuator, and the AGV safety control system and the AGV driving control system will simultaneously start the safety function detection.

[0081] 1) Travel distance safety detection closed-loop: The maximum allowable travel distance value after the personnel detection device is turned off is 1800 mm. When the travel servo motor receives a travel control command, the AGV host computer reads Dc1 = 100 mm and Dc2 = 101 mm. The travel servo motor enables the travel motor and the wheels to start moving. The AGV host computer obtains Ds1 = 1895 mm and Ds2 = 1906 mm. Then, it can be calculated that:

[0082] Da1: 1795 = 1895 – 100;

[0083] Da2: 1805 = 1906 – 101;

[0084] a. Safety control channel 1: Since Da1 is less than Dsmax, the AGV travel control system continues to maintain detection;

[0085] b. Safety control channel 2: Since Da2 is greater than Dsmax, the AGV safety control system immediately cuts off the power supply of the travel actuator, and the AGV reports a fault to prevent continued movement from causing harm to personnel or goods.

[0086] 2) Travel speed safety detection closed-loop: Vsmax is 300 mm / s, Vv = 30 mm / s. The data of the previous moment is Dcp1 = 100 mm, Dcp2 = 101 mm, and the time Tp = 30 s; the current position data is Dc1 = 890 mm, Dcp2 = 1001 mm, and the time T = 33 s. Then, it can be calculated that:

[0087] Va1: 263.3 ≈ (890 - 100) / (33 - 30)

[0088] Va2: 310 = (1031 - 101) / (33 - 30)

[0089] Va2 – Va1 = 46.7

[0090] a. When the absolute value of Va1 - Va2, which is 46.7 mm / s, is greater than Vv, the safety PLC controller determines that the difference between the two speed data is too large and immediately cuts off the power supply of the travel actuator to stop the movement of the travel execution mechanism, preventing continued movement from causing harm to personnel or goods;

[0091] b. Since Va2 is greater than Vsmax, the safety PLC controller determines that the vehicle travel speed exceeds the safety set value and immediately cuts off the power supply of the travel actuator to stop the movement of the travel execution mechanism, preventing continued movement from causing harm to personnel or goods.

[0092] Embodiment 2

[0093] The AGV safety control method of this embodiment is applied to the scenario of safety control during the AGV lifting process.

[0094] See Figure 6 As shown, a method for AGV safety control in this embodiment includes:

[0095] S501, the first control system sends a lifting control instruction to the lifting actuator and the second control system;

[0096] S502, the lifting actuator controls the lifting execution mechanism to execute the control instruction;

[0097] S503, the position sensor of the lifting mechanism collects the position data of the operation of the lifting execution mechanism and sends it to the second control system;

[0098] S504, the second control system calculates motion data based on the position data and makes a judgment; the motion data includes at least one of motion speed, position deviation, and distance deviation;

[0099] S505, when the second control system determines that one of the motion data exceeds the AGV safety limit, it controls the lifting actuator to stop executing.

[0100] See Figure 7 As shown, in this embodiment, in order to achieve redundant control and ensure control safety, the position data collected by the position sensor can also be sent to the first control system, and the first control system also performs detection and control, specifically including:

[0101] The position sensor of the lifting mechanism collects the position data of the operation of the lifting execution mechanism and sends it to the first control system;

[0102] The first control system calculates motion data based on the position data and makes a judgment;

[0103] When the first control system determines that one of the motion data exceeds the AGV safety limit, it stops sending the lifting control instruction, the lifting actuator controls the lifting execution mechanism to stop acting, and reports a fault. After the second controller detects the fault, it controls the lifting actuator to stop executing.

[0104] In this embodiment, the first control system is an AGV lifting control system; the second control system is an AGV safety control system.

[0105] Specifically, the position sensor of the lifting mechanism includes one or two.

[0106] When the position sensor of the lifting mechanism is one, the motion data includes position deviation and / or motion speed; the position deviation is equal to the difference between the target position and the current position collected by the position sensor; the motion speed is equal to the quotient of the difference between the position at the current moment and the position at the previous moment collected by the position sensor and the time difference.

[0107] See Figure 8 As shown, in this embodiment, two lifting mechanism position sensors are used to detect the position of the lifting actuator mechanism. The redundant detection method makes the lifting detection safer and more reliable. The two lifting mechanism position sensors are respectively the first lifting mechanism position sensor and the second lifting mechanism position sensor, which can be installed on the AGV chassis. The motion data includes at least one of position deviation, motion speed, and distance deviation; the position deviation is equal to the difference between the target position and the current position collected by the first lifting mechanism position sensor / second lifting mechanism position sensor; the motion speed is equal to the quotient of the difference between the position at the current moment and the previous moment collected by the first lifting mechanism position sensor / second lifting mechanism position sensor and the time difference, or the motion speed is equal to the average value of the motion speed of the first lifting mechanism position sensor and the motion speed of the second lifting mechanism position sensor; the distance deviation is equal to the difference between the current position collected by the first lifting mechanism position sensor and the current position collected by the second lifting mechanism position sensor.

[0108] See Figure 9 As shown, the specific control process is as follows.

[0109] 1. After the AGV lifting function starts to run, the safety control system of the AGV will start to work and control the power supply of the lifting actuator. Then the lifting control system of the AGV will start to control the lifting actuator, and the lifting actuator will control the lifting actuator mechanism to move. During the movement of the lifting actuator mechanism, the first lifting mechanism position sensor and the second lifting mechanism position sensor will measure the position of the lifting actuator mechanism in real time and feedback the data to the AGV lifting control system and the lifting safety control system respectively for control closed-loop and safety closed-loop.

[0110] 2. When the AGV issues a lifting control command (the lifting control command carries the target position Ds and the lifting speed command Vs), both the safety control system and the lifting actuator will receive the lifting control command;

[0111] 1) Lifting system control closed-loop: The lifting actuator receives the lifting control command, enables the lifting mechanism to start moving, and the AGV lifting system reads the data Dc1 of the lifting mechanism position sensor 1 in real time.

[0112] a. When the lifting mechanism moves to the target position Ds and the AGV lifting system determines that Ds is not equal to Dc1, the AGV lifting system calculates the deviation value between the two data and issues a command to the lifting actuator again until the lifting mechanism is adjusted to the target position Ds;

[0113] b. When the lifting mechanism moves to the target position Ds and the AGV lifting system determines that Ds is equal to Dc1, the AGV lifting system turns off the enabling of the lifting actuator, and the lifting mechanism stops, completing the control of this lifting action.

[0114] 2) Safety closed-loop of the lifting system: When the safety control system receives the lifting control instruction, it starts to read the data Dc1 of the first lifting mechanism position sensor and the data Dc2 of the second lifting mechanism position sensor in real time:

[0115] a. The safety control system compares Dc1 and Dc2 in real time. If the absolute value of Dc1 minus Dc2 exceeds the safety distance deviation value Dv, the safety control system determines that the position data feedback fails, immediately cuts off the power supply of the lifting actuator, and stops the movement of the lifting actuator mechanism to prevent continued movement from causing harm to personnel or goods;

[0116] b. The safety control system calculates the movement speed of the forklift according to the position change data of Dc1 and Dc2. The calculation method is as follows:

[0117] The position data Dcp1 of the lifting mechanism position sensor 1 at the previous moment, the time is Tp; the current position data Dc1, the time is T;

[0118] The position data Dcp2 of the lifting mechanism position sensor 2 at the previous moment, the time is Tp; the current position data Dc2, the time is T;

[0119] The calculation method of the actual movement speed V of the lifting mechanism is as follows:

[0120] Vc = ((Dc1 - Dcp1) / (T - Tp) + (Dc2 - Dcp2) / (T - Tp)) / 2

[0121] When the safety controller determines that the absolute value of Vc - Vs exceeds the safety speed deviation value Vv, the safety system determines that the lifting actuator or the lifting actuator mechanism responds abnormally, immediately cuts off the power supply of the lifting actuator, and stops the movement of the lifting actuator mechanism to prevent continued movement from causing harm to personnel or goods.

[0122] See Figure 10 As shown, based on the safety closed-loop control function of the lifting safety control system, calculations are made in sistema, and the safety level can reach PLd.

[0123] The following will take specific detection data as an example to illustrate the safety control.

[0124] When applied to an AGV with a fork, the lifting actuator is the servo controller of the lifting motor, the lifting actuator mechanism is the lifting motor, the push rod, and the fork. The lifting mechanism position sensor can use 2 absolute value wire rope encoders or 2 laser sensors or a combination of the two sensors to obtain the height of the fork during movement. The AGV lifting control system is the upper computer of the AGV, and the safety control system of the AGV is the safety PLC controller. The upper computer of the AGV sends the target speed of 300 mm / s for lifting control and the target position of 1000 mm for lifting to the lifting servo controller and the safety PLC controller. The servo controller enables the lifting motor to rotate, and the push rod drives the fork to move.

[0125] 1) Lifting system control closed-loop: If Dc1 = 900 mm, the AGV calculates the height deviation value as: 1000 mm - 900 mm = 100 mm; continue to send a lifting command to the servo controller to adjust the position of the fork until Dc1 = 1000 m, then stop sending the control command.

[0126] 2) Lifting system safety closed-loop:

[0127] a. The safety control system compares Dc1 and Dc2 in real time. If Dc1 = 900 mm and Dc2 = 850 mm, the deviation value of the safety distance is 10 mm, Dc1 - Dc2 = 50 mm, which is greater than the deviation value of the safety distance of 10 mm. The safety control system determines that the position data feedback fails, immediately cuts off the power supply of the servo motor, and stops the movement of the fork to prevent continued movement from causing harm to personnel or goods;

[0128] b. Dcp1 = 100 mm, Dcp2 = 101 mm, the time is Tp = 30 s; the current position data Dc1 = 1300 mm, the current position data Dc2 = 1301, the time is T = 33 s; at time T, the deviation value of the safety speed is 30 mm / s;

[0129] The calculation method of the actual movement speed V of the lifting mechanism is as follows:

[0130] 400 mm / s = ((1300 mm - 100 mm) / (33 s - 30 s) + (1301 mm - 101 mm) / (33 s - 30 s)) / 2

[0131] V - Vs = 100 mm / s, which is greater than the deviation value of the safety speed of 30 mm / s. The safety PLC controller determines that the lifting actuator or the lifting actuator mechanism responds abnormally, immediately cuts off the power supply of the lifting actuator, and stops the movement of the lifting actuator mechanism to prevent continued movement from causing harm to personnel or goods.

[0132] Embodiment III

[0133] This embodiment discloses an AGV vehicle, including: a first control system, a second control system, an actuator, an actuator mechanism, and a position sensor;

[0134] The first control system is configured to send control instructions to the actuator;

[0135] The actuator is configured to control the actuator mechanism to execute the control instructions;

[0136] The position sensor is configured to collect the position data of the operation of the actuator mechanism and send it to the second control system;

[0137] The second control system is configured to calculate motion data based on the position data and make a judgment; the motion data includes at least one of travel distance, motion speed, speed deviation, position deviation, and distance deviation; when the second control system determines that one of the motion data exceeds the AGV safety limit, it controls the actuator to stop execution.

[0138] Furthermore, the position sensor is also configured to collect the position data of the operation of the actuator mechanism and send it to the first control system; the first control system is also configured to calculate motion data based on the position data and make a judgment; when the first control system determines that one of the motion data exceeds the AGV safety limit, it stops sending control instructions, the actuator controls the actuator mechanism to stop acting, and reports a fault, and after the second controller detects the fault, it controls the actuator to stop execution.

[0139] When the AGV vehicle of this embodiment is only used in the scenario of Embodiment 1, the first control system is the AGV travel control system, the second control system is the AGV safety control system, the actuator is the travel actuator, the actuator mechanism is the travel actuator mechanism, and the position sensor is the travel position sensor.

[0140] When the AGV vehicle of this embodiment is only used in the scenario of Embodiment 2, the first control system is the AGV lifting control system, the second control system is the AGV safety control system, the actuator is the lifting actuator, the actuator mechanism is the lifting actuator mechanism, and the position sensor is the lifting mechanism position sensor.

[0141] When the AGV vehicle in this embodiment can be used in the scenarios of Embodiment 1 and Embodiment 2 at the same time, that is, when the functions of Embodiment 1 are activated during driving and the functions of Embodiment 2 are activated during lifting, the AGV vehicle needs to include an AGV driving control system, an AGV lifting control system, an AGV safety control system, a driving actuator, a driving actuator mechanism, a driving position sensor, a lifting actuator, a lifting actuator mechanism, and a lifting mechanism position sensor. The AGV driving control system and the AGV lifting control system can be integrated into one system, and the AGV safety control system can also be integrated or independently deployed, which is specifically set according to needs and is not limited in this embodiment.

[0142] The above are only specific embodiments of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantive modification made to the present invention using this concept shall fall within the scope of infringement of the protection of the present invention.

Claims

1. An AGV safety control method, characterized in that, it includes: The first control system sends a control instruction to the actuator; The actuator controls the actuator mechanism to execute the control instruction; The position sensor collects the position data of the operation of the actuator mechanism and sends it to the second control system; The second control system calculates and judges the motion data based on the position data; the motion data includes at least one of the travel distance, motion speed, speed deviation, position deviation, and distance deviation; When the second control system determines that one of the motion data exceeds the AGV safety limit, it controls the actuator to stop execution.

2. The AGV safety control method according to claim 1, characterized in that, The actuator is a travel actuator; the actuator mechanism is a travel actuator mechanism; the position sensor is a travel position sensor; the control instruction includes a travel control instruction; Before the actuator controls the actuator mechanism to execute the control instruction, it further includes: The first control system sends a personnel detection shutdown instruction to the second control system; after receiving the personnel detection shutdown instruction, the second control system starts to monitor the position data sent by the position sensor.

3. The AGV safety control method according to claim 2, characterized in that, The position sensor includes one; the motion data includes the travel distance and / or the motion speed; the travel distance is equal to the difference between the current position collected by the position sensor and the position when the travel control instruction is received; the motion speed is equal to the quotient of the difference between the position at the current moment and the previous moment collected by the position sensor and the time difference.

4. The AGV safety control method according to claim 2, characterized in that, The position sensor includes two, namely the first travel position sensor and the second travel position sensor; the motion data includes at least one of the travel distance, motion speed, and speed deviation; the travel distance is equal to the difference between the current position collected by the first travel position sensor / second travel position sensor and the position when the travel control instruction is received; the motion speed is equal to the quotient of the difference between the position at the current moment and the previous moment collected by the first travel position sensor / second travel position sensor and the time difference; the speed deviation is equal to the absolute value of the difference between the motion speed of the first travel position sensor and the motion speed of the second travel position sensor.

5. The AGV safety control method according to claim 1, characterized in that, The actuator is a lifting actuator; the actuator mechanism is a lifting actuator mechanism; the position sensor is a lifting mechanism position sensor; the control instruction includes a lifting control instruction; Before the actuator controls the actuator mechanism to execute the control instruction, it further includes: The first control system sends a control instruction to the second control system; After receiving the control instruction, the second control system starts to monitor the position data sent by the position sensor.

6. The AGV safety control method according to claim 5, characterized in that, The position sensor includes one; the motion data includes a position deviation and / or a motion speed; the position deviation is equal to the difference between the target position and the current position collected by the position sensor; the motion speed is equal to the quotient of the difference between the position at the current moment and the position at the previous moment collected by the position sensor and the time difference.

7. The AGV safety control method according to claim 5, wherein, the position sensor includes two, namely a first lifting mechanism position sensor and a second lifting mechanism position sensor; the motion data includes at least one of a position deviation, a motion speed, and a distance deviation; the position deviation is equal to the difference between the target position and the current position collected by the first lifting mechanism position sensor / second lifting mechanism position sensor; the motion speed is equal to the quotient of the difference between the position at the current moment and the position at the previous moment collected by the first lifting mechanism position sensor / second lifting mechanism position sensor and the time difference, or the motion speed is equal to the average value of the motion speed of the first lifting mechanism position sensor and the motion speed of the second lifting mechanism position sensor; the distance deviation is equal to the difference between the current position collected by the first lifting mechanism position sensor and the current position collected by the second lifting mechanism position sensor.

8. The AGV safety control method according to claim 1, wherein, further comprising: The position sensor collects the position data of the operation of the actuator and sends it to the first control system; The first control system calculates the motion data based on the position data and makes a judgment; When the first control system determines that one of the motion data exceeds the AGV safety limit, it stops sending control commands, the actuator controls the actuator to stop operating, and reports a fault. After the second controller detects the fault, it controls the actuator to stop execution.

9. An AGV vehicle, wherein, comprising: A first control system, a second control system, an actuator, an actuator mechanism, and a position sensor; The first control system is configured to send control commands to the actuator; The actuator is configured to control the actuator mechanism to execute the control commands; The position sensor is configured to collect the position data of the operation of the actuator mechanism and send it to the second control system; The second control system is configured to calculate the motion data based on the position data and make a judgment; the motion data includes at least one of a travel distance, a motion speed, a speed deviation, a position deviation, and a distance deviation; when the second control system determines that one of the motion data exceeds the AGV safety limit, it controls the actuator to stop execution.

10. The AGV safety control system according to claim 9, wherein, The position sensor is further configured to collect position data of the operation of the actuator and send it to the first control system; the first control system is further configured to calculate motion data based on the position data and make a judgment; when the first control system determines that one of the motion data exceeds the AGV safety limit, it stops sending control commands, the actuator controls the actuator to stop operating, and reports a fault, and after the second controller detects the fault, it controls the actuator to stop execution.

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