Drilling machine overturn-preventing early warning method, system and equipment and storage medium
By installing sensors on the drilling rig and establishing a three-dimensional coordinate system, the gravity matrix of the boom and the vehicle body can be calculated in real time, and the overturning risk factor can be quantified. This solves the problem of overturning risk when the drilling rig is operating on steep terrain and achieves real-time early warning and safety assurance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUNAN CHUANGYUAN HIGH TECH MACHINERY CO LTD
- Filing Date
- 2025-12-01
- Publication Date
- 2026-04-24
AI Technical Summary
When drilling rigs operate on steep slopes, relying on the operator's experience to prevent overturning can easily lead to operational errors. The inability to quantify and analyze overturning risks results in frequent overturning accidents.
By installing sensors on the drilling rig, a three-dimensional coordinate system is established to obtain the attitude and center of gravity information of the vehicle body and joints in real time, calculate the gravity matrix of the boom and vehicle body, quantify the overturning risk factor, and provide real-time early warning.
It enables real-time early warning of drilling rig overturning risks, reduces the occurrence of overturning accidents, and ensures the safety of equipment and personnel.
Smart Images
Figure CN121921916A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of mechanical control technology, specifically to a method, system, equipment, and storage medium for preventing overturning of drilling rigs. Background Technology
[0002] Drilling rigs are mechanical devices used for drilling holes in rocks before engineering blasting. They are widely used in complex operation scenarios such as mining and infrastructure construction, and their operating environments often involve terrain with large slopes. When moving or working in sloping areas, the center of gravity of the drilling rig will shift due to the terrain tilt. The multi-joint movements of the drill arm (such as swinging, pitching, and compensation) will further change the position of the overall center of gravity, significantly increasing the risk of the center of gravity exceeding the stable support range and easily causing overturning accidents.
[0003] Currently, preventing drilling rigs from overturning mainly relies on operators. In operation scenarios with steep slopes, overturning is prevented by retracting the drill arm onto the rig body and controlling the vehicle's speed. However, relying on operators to ensure the rig's safety is prone to errors due to varying operator skill levels or understanding. Furthermore, it's difficult to quantify and analyze overturning risks, and it's hard to provide early warnings of critical dangerous situations, resulting in a high risk of rig overturning. Summary of the Invention
[0004] In view of this, the present invention provides a drilling rig anti-overturning early warning method, system, equipment and storage medium to solve the problem of high risk of overturning of drilling rigs when operating on terrain with large slopes.
[0005] In a first aspect, the present invention provides a method for preventing overturning of a drilling rig, the drilling rig comprising: a fixed body, a boom cascaded via multiple movable joints, a first sensor mounted on the body; and second sensors mounted on each joint, the method comprising: A three-dimensional coordinate system is established based on the three-dimensional model of the target drilling rig, and the coordinates of the vehicle's center of gravity and the transformation matrix of the center of gravity of each joint relative to that joint are obtained in the three-dimensional coordinate system. The vehicle attitude is acquired using the first sensor, and the vehicle gravity matrix is determined based on the vehicle attitude, the coordinates of the vehicle's center of gravity, and the vehicle's gravity. The pose of each joint is acquired using the second sensor, and the pose transformation matrix of each joint relative to the previous joint is determined based on the pose of each joint and the vehicle body pose. Obtain the gravity of each joint, and calculate the boom gravity matrix based on the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix; The risk factor is calculated based on the boom gravity matrix and the vehicle gravity matrix, and an overturning warning is issued for the target drilling rig based on the risk factor.
[0006] The drilling rig anti-tipping early warning method provided by this invention uses sensors to acquire the vehicle body attitude and the attitude of each joint in real time, and calculates the boom gravity matrix and vehicle gravity matrix in real time. Based on the boom gravity matrix and vehicle gravity matrix, the overturning risk coefficient of the target drilling rig is calculated in real time. This avoids the risk of overturning when the drilling rig is operating on a steep slope and the operator's experience is the only factor that can cause the overturning. This method provides real-time early warning of overturning risk and reduces the occurrence of overturning accidents.
[0007] In one optional implementation, one axis of the three-dimensional coordinate system is the rotation axis of the vehicle body tilt. Obtaining the coordinates of the vehicle's center of gravity and the joint center of gravity transformation matrix of each joint relative to that joint in the three-dimensional coordinate system includes: Based on the three-dimensional coordinate system, obtain the coordinates of the vehicle's center of gravity, the coordinates of each joint, and the coordinates of the center of gravity of each joint in the three-dimensional coordinate system. Based on the coordinates of each joint and the corresponding coordinates of the joint centroid, determine the centroid transformation matrix of each joint.
[0008] The drilling rig anti-tipping early warning method provided by this invention establishes a three-dimensional coordinate system to accurately describe the spatial positional relationship between the vehicle's center of gravity and the center of gravity of each joint when the vehicle is tilted. Based on accurate coordinates and transformation matrices, it scientifically and rationally analyzes the force and center of gravity distribution of the drilling rig under tilting conditions, thereby improving the accuracy of judging the risk of drilling rig overturning.
[0009] In one optional implementation, the first sensor is a dual-axis tilt sensor, and the vehicle attitude includes: the vehicle tilt direction, a first tilt angle and a second tilt angle in the vehicle tilt direction; The vehicle gravity matrix is determined based on the vehicle's attitude, center of gravity coordinates, and gravity forces, including: The rotation matrix for vehicle tilt is determined based on the first and second tilt angles in the vehicle tilt direction; The homogeneous transformation matrix of the vehicle body is determined based on the rotation matrix, and the lever arm vector of the vehicle's center of gravity coordinates relative to the preset rotation axis is determined based on the homogeneous transformation matrix. The gravitational torque of the vehicle body is determined based on the coordinates of the vehicle's center of gravity and its lever arm vector relative to the preset rotation axis.
[0010] The drilling rig anti-tipping early warning method provided by this invention uses a dual-axis tilt sensor to obtain the first and second tilt angles of the vehicle body in the tilt direction, thereby determining the vehicle body tilt rotation matrix, and then obtaining the homogeneous transformation matrix of the vehicle body and the distance between the vehicle body's center of gravity and the rotation axis. Combined with the vehicle body's gravity, the vehicle body gravity matrix is determined, and the gravity moment under the vehicle body tilt state is accurately quantified, providing reliable vehicle body-end data support for subsequent comparison with the boom gravity moment and assessment of the drilling rig's overturning risk.
[0011] In one optional implementation, the second sensor is an angle or length sensor, and the joint posture includes: joint angle or joint length; Based on the posture of each joint and the vehicle body posture, determine the pose transformation matrix of each joint relative to the previous joint, including: The vehicle body posture is determined based on the vehicle body posture, and the pose transformation matrix of the first joint relative to the vehicle body is determined based on the vehicle body posture and the joint posture of the first joint connected to the vehicle body. By combining the DH model of the boom and the posture of each joint, the pose transformation matrix of the remaining joints (excluding the first joint) relative to the previous joint is determined.
[0012] In one optional implementation, the boom gravity matrix is calculated based on the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix, including: Based on the vehicle's center of gravity coordinates, the center of gravity transformation matrix of each joint, and the corresponding pose transformation matrix, the center of gravity pose of each joint is determined sequentially. The center of gravity position vector of each joint is determined based on the center of gravity pose of each joint, and the gravity matrix of each joint is determined by combining the gravity of each joint. The gravity matrices of each joint are added together to obtain the gravity matrix of the boom.
[0013] The drilling rig anti-tipping early warning method provided by this invention uses angle or length sensors to obtain joint postures such as joint angles or lengths. Combined with the vehicle body posture, the pose transformation matrix of each joint relative to the previous joint is determined. Based on the vehicle's center of gravity coordinates, the center of gravity transformation matrix of each joint, and the pose transformation matrix, the center of gravity posture of each joint is determined. Then, combined with the gravity of each joint, the gravity matrix of each joint is obtained. This accurately obtains the relevant data of the pose and gravitational moment of each joint of the boom, providing accurate boom-end data for subsequent assessment of drilling rig overturning risk and improving the accuracy of hazard judgment.
[0014] In one optional implementation, a risk factor is calculated based on the boom gravity matrix and the vehicle gravity matrix, and an overturning warning is issued for the target drilling rig based on the risk factor, including: Divide the boom gravity matrix by the vehicle gravity matrix to obtain the risk factor, which ranges from (-1, 1). Based on the risk factor and its range, an early warning strategy is determined. The smaller the difference between the risk factor and -1, the greater the likelihood that the target drilling rig will overturn.
[0015] The drilling rig anti-overturning early warning method provided by this invention obtains a risk coefficient by dividing the boom gravity matrix by the vehicle gravity matrix, and then issues an early warning based on the risk coefficient. This accurately quantifies the degree of overturning risk of the drilling rig, allowing operators to clearly understand the risk status of the equipment and take timely countermeasures. This effectively reduces the probability of overturning accidents during drilling operations, ensures equipment safety and the personal safety of operators, and reduces losses such as equipment damage and project delays caused by overturning.
[0016] In one alternative implementation, the method further includes: If the target drilling rig is in motion, the speed sensor is used to obtain the vehicle speed and / or boom speed, and the influencing factor is determined based on the vehicle speed and / or boom speed. Based on the influencing factors, the boom gravity matrix is calculated according to the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix.
[0017] The drilling rig anti-tipping early warning method provided by this invention analyzes the vehicle speed and / or boom speed under motion, and fully considers the influence of speed on boom gravity moment under motion, so that the calculation of boom gravity matrix is more in line with actual working conditions, making the calculation of risk factor and overturning early warning more accurate in subsequent motion, effectively improving the accuracy of overturning risk assessment of drilling rig during dynamic operation, and better protecting equipment and personnel safety.
[0018] Secondly, the present invention provides a drilling rig anti-tipping early warning system, the drilling rig including: a fixed vehicle body, a boom cascaded through multiple movable joints, a first sensor mounted on the vehicle body; and second sensors mounted on each joint, the system including: The coordinate system establishment module is used to establish a three-dimensional coordinate system based on the three-dimensional model of the target drilling rig, and to obtain the coordinates of the vehicle's center of gravity and the joint center of gravity transformation matrix of each joint relative to that joint in the three-dimensional coordinate system. The vehicle gravity matrix determination module is used to acquire the vehicle attitude using the first sensor, and determine the vehicle gravity matrix based on the vehicle attitude, the vehicle center of gravity coordinates, and the vehicle gravity. The joint pose determination module is used to acquire the pose of each joint using the second sensor, and to determine the pose transformation matrix of each joint relative to the previous joint based on the pose of each joint and the vehicle body pose. The boom gravity matrix determination module is used to obtain the gravity of each joint and calculate the boom gravity matrix based on the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix. The hazard warning module is used to calculate the hazard coefficient based on the boom gravity matrix and the vehicle gravity matrix, and to provide an overturning warning for the target drilling rig based on the hazard coefficient.
[0019] Thirdly, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the method described in the first aspect or any corresponding embodiment thereof.
[0020] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to perform the method described in the first aspect or any corresponding embodiment thereof. Attached Figure Description
[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0022] Figure 1 This is a schematic flowchart of a drilling rig anti-overturning early warning method according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the target drilling rig in the drilling rig anti-overturning early warning method according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure for establishing a three-dimensional coordinate system in the drilling rig anti-overturning early warning method according to an embodiment of the present invention; Figure 4 This is a structural schematic diagram of the center of gravity and joint position of each joint in the drilling rig anti-overturning early warning method according to an embodiment of the present invention; Figure 5 This is a flowchart illustrating another drilling rig anti-overturning early warning method according to an embodiment of the present invention; Figure 6 This is a structural schematic diagram of the vehicle weight and the weight of each joint in the drilling rig anti-overturning early warning method according to an embodiment of the present invention; Figure 7 This is a structural block diagram of a drilling rig anti-overturning early warning system according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. Detailed Implementation
[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0024] For example, an embodiment of the present invention provides a drilling rig anti-overturning early warning method, which obtains a risk coefficient by calculating the vehicle gravity matrix and the boom gravity matrix, and performs early warning based on the risk coefficient, so as to achieve the effect of accurately predicting overturning danger and providing early warning.
[0025] According to an embodiment of the present invention, a drilling rig anti-overturning early warning method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.
[0026] This embodiment provides a drilling rig anti-tipping early warning method, which can be used in the aforementioned computer system. The drilling rig includes: a fixed body, a boom connected by multiple movable joints, a first sensor mounted on the body, and second sensors mounted on each joint. Figure 1 This is a flowchart of a drilling rig anti-overturning early warning method according to an embodiment of the present invention, such as... Figure 1 As shown, the process includes the following steps: Step S101: Establish a three-dimensional coordinate system based on the three-dimensional model of the target drilling rig, and obtain the coordinates of the vehicle's center of gravity and the joint center of gravity transformation matrix of each joint relative to that joint in the three-dimensional coordinate system.
[0027] Specifically, a three-dimensional model of the target drilling rig can be created using Solidworks software, such as... Figure 2 The diagram shown is a structural schematic of a drilling rig and its installed sensors, including: a fixed vehicle body 1, a first joint 2 (drill arm swing joint), a second joint 3 (drill arm pitch joint), a third joint 4 (drill frame pitch joint), a fourth joint 5 (drill frame swing joint), a fifth joint 6 (drill frame compensation joint), a vehicle tilt sensor 7, a vehicle speed sensor 8, a drill arm swing angle sensor 9, a drill arm pitch angle sensor 10, a drill frame pitch angle sensor 11, a drill frame swing angle sensor 12, a drill frame compensation length sensor 13, and a forward tilting shaft 14 (vertical view). The boom of this drilling rig includes five joints, which is only an example and is not a limitation.
[0028] Establish a suitable 3D coordinate system based on the 3D model, such as Figure 3The diagram shows a 3D coordinate system established when the drilling rig tilts forward. Solidworks software can directly obtain the vehicle's center of gravity coordinates, joint coordinates, and joint center of gravity coordinates within the coordinate system. The determination of these coordinates is a built-in function of Solidworks software and will not be elaborated here. Then, based on the joint coordinates and their corresponding center of gravity coordinates, the joint center of gravity transformation matrix for each joint is determined, as shown below. Figure 4 The diagram shown is a schematic of the joint-related matrix, where... Let represent the centroid transformation matrix of the i-th joint.
[0029] Step S102: Use the first sensor to acquire the vehicle body attitude, and determine the vehicle gravity matrix based on the vehicle body attitude, the vehicle center of gravity coordinates, and the vehicle gravity.
[0030] Specifically, the first sensor is Figure 2 The dual-axis tilt sensor installed on the vehicle is used to obtain the vehicle tilt state. The vehicle attitude will affect the vehicle gravity matrix. Therefore, the first sensor is used to obtain the vehicle attitude, and the rotation matrix of the vehicle tilt is determined based on the vehicle attitude. Then, the vehicle gravity matrix is calculated by combining the vehicle center coordinates and the vehicle gravity.
[0031] Step S103: Use the second sensor to acquire the posture of each joint, and determine the pose transformation matrix of each joint relative to the previous joint based on the posture of each joint and the posture of the vehicle body.
[0032] Specifically, the type and number of the second sensors are related to the type of boom and joint, such as... Figure 2 As shown, the angle sensor corresponding to the drill arm swing joint and the length sensor corresponding to the drill frame compensation joint are only examples and are not limited thereto. The second sensor includes: the drill arm swing angle sensor corresponding to the first joint, the drill arm pitch angle sensor corresponding to the second joint, the drill frame pitch angle sensor corresponding to the third joint, the drill frame swing angle sensor corresponding to the fourth joint, and the drill frame compensation length sensor corresponding to the fifth joint.
[0033] The pose of each joint is acquired using the second sensor and combined with the vehicle body pose. The pose transformation matrix of each joint relative to the previous joint is determined. The previous joint of the first joint is the vehicle body. The pose transformation matrix of the first joint relative to the vehicle body can be determined based on the vehicle body pose and the first joint pose. Similarly, the pose transformation matrix of each joint relative to the previous joint can be obtained. When the pose of a certain joint or the vehicle body is determined, the pose of the remaining joints can be calculated using the pose transformation matrix.
[0034] Step S104: Obtain the gravity of each joint, and calculate the boom gravity matrix based on the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix.
[0035] Specifically, the gravity of each joint is obtained using mature existing technology. The joint center of gravity transformation matrix is used to describe the positional relationship between the joint center of gravity and the corresponding joint in the three-dimensional coordinate system. It can be obtained through Solidworks software, and the method of obtaining it is a mature existing technology, which will not be elaborated here.
[0036] By using the pose transformation matrix of each joint relative to the previous joint, combined with the joint center of gravity transformation matrix, the center of gravity position of each joint can be obtained. Combined with the gravity of each joint, the gravity matrix of each joint can be obtained, and then the gravity matrix of the entire boom can be obtained.
[0037] Step S105: Calculate the risk factor based on the boom gravity matrix and the vehicle gravity matrix, and issue an overturning warning for the target drilling rig based on the risk factor.
[0038] Specifically, the vehicle gravity matrix reflects the torque generated by the vehicle's own weight, providing basic support for the vehicle's stability. The boom gravity matrix, on the other hand, reflects the torque generated by the boom's weight, which can interfere with the vehicle's balance. When the two have opposite signs, it means that the boom gravity torque and the vehicle gravity torque act in opposite directions and will counteract each other; when they have the same sign, the boom gravity torque and the vehicle gravity torque act in the same direction and can jointly contribute to the vehicle's stability. Therefore, the boom gravity matrix and the vehicle gravity matrix can be used to calculate the risk factor of the target drilling rig overturning and to provide overturning warnings based on the risk factor.
[0039] The drilling rig anti-tipping early warning method provided in this embodiment uses sensors to acquire the vehicle body attitude and the attitude of each joint in real time, and calculates the boom gravity matrix and vehicle gravity matrix in real time. Based on the boom gravity matrix and vehicle gravity matrix, the overturning risk coefficient of the target drilling rig is calculated in real time. This avoids the risk of overturning when the drilling rig is operating on a steep slope and the operator's experience is the only factor that can cause the overturning. This method provides real-time early warning of overturning risk and reduces the occurrence of overturning accidents.
[0040] This embodiment provides a drilling rig anti-overturning early warning method, which can be used in the aforementioned computer system. Figure 5 This is a flowchart of a drilling rig anti-overturning early warning method according to an embodiment of the present invention, such as... Figure 5 As shown, the process includes the following steps: Step S201: Establish a three-dimensional coordinate system based on the three-dimensional model of the target drilling rig, and obtain the coordinates of the vehicle's center of gravity and the joint center of gravity transformation matrix of each joint relative to that joint in the three-dimensional coordinate system.
[0041] Specifically, one coordinate axis of the three-dimensional coordinate system is the rotation axis of the vehicle body tilt. Step S201 above, which obtains the coordinates of the vehicle's center of gravity in the three-dimensional coordinate system and the joint center of gravity transformation matrix of each joint relative to that joint, includes: Step S2011: Based on the three-dimensional coordinate system, obtain the coordinates of the vehicle's center of gravity, the coordinates of each joint, and the coordinates of the center of gravity of each joint in the three-dimensional coordinate system.
[0042] Specifically, taking forward tilting as an example, a three-dimensional coordinate system is established with the forward tilting axis as the y-axis and the direction perpendicular to the image inward as the negative y-axis. This is just an example and is not a limitation. The coordinates of the vehicle's center of gravity p(x) are obtained. p y p , z p ), the coordinates of each joint qi (x) qi y qi , z qi ), the centroid coordinates pi (x) of each joint pi y pi , z pi ), where i represents the i-th joint cascaded starting from the vehicle body.
[0043] Step S2012: Determine the joint centroid transformation matrix for each joint based on the joint coordinates and the corresponding joint centroid coordinates.
[0044] Specifically, based on the coordinates qi (x) of each joint qi y qi , z qi ) and the corresponding joint centroid coordinates pi (x pi y pi , z pi Determine the joint centroid transformation matrix for each joint. The attitude matrix is an identity matrix. In this embodiment, the coordinates of each joint are the coordinates of the connection between each joint and the previous joint, and the coordinates of the center of gravity of each joint are the coordinates of the center of gravity of the boom connecting rod to which each joint is located.
[0045] The drilling rig anti-tipping early warning method provided in this embodiment establishes a three-dimensional coordinate system to accurately describe the spatial positional relationship between the vehicle's center of gravity and the center of gravity of each joint when the vehicle is tilted. Based on accurate coordinates and transformation matrices, it scientifically and rationally analyzes the force and center of gravity distribution of the drilling rig under tilting conditions, thereby improving the accuracy of judging the risk of drilling rig overturning.
[0046] Step S202: Use the first sensor to acquire the vehicle's attitude, and determine the vehicle's gravity matrix based on the vehicle's attitude, the coordinates of the vehicle's center of gravity, and the vehicle's gravity.
[0047] Specifically, the first sensor is a dual-axis tilt sensor, and the vehicle attitude includes: the vehicle tilt direction, a first tilt angle and a second tilt angle in the vehicle tilt direction. Step S202 above includes: Step S2021: Determine the rotation matrix of the vehicle body tilt based on the first tilt angle and the second tilt angle of the vehicle body tilt direction.
[0048] Specifically, taking the forward tilting of the vehicle as an example, the tilt direction is forward. A dual-axis tilt sensor is used to obtain the tilt angles in the forward and backward directions as the first tilt angle α, and the tilt angles in the left and right directions as the second tilt angle β. The rotation matrix of the vehicle tilt is then calculated using the first tilt angle α and the second tilt angle β. .
[0049] Step S2022: Determine the homogeneous transformation matrix of the vehicle body based on the rotation matrix, and determine the lever arm vector of the vehicle's center of gravity coordinates relative to the preset rotation axis based on the homogeneous transformation matrix.
[0050] Specifically, the homogeneous transformation matrix of the vehicle body is determined based on the rotation matrix. (R is the attitude matrix), calculate the vehicle's center of gravity pose matrix at the first and second tilt angles based on the vehicle's center of gravity coordinates and homogeneous transformation matrix. Given the coordinates of the center of gravity as [x, y, z], the lever arm vector of the vehicle's center of gravity G relative to the preset rotation axis (y-axis) can be obtained. The preset rotation axis is the direction with the highest probability of overturning, which is the rotation axis when the vehicle body overturns.
[0051] Step S2023: Determine the gravitational torque of the vehicle body based on the coordinates of the vehicle's center of gravity and its lever arm vector with respect to the preset rotation axis.
[0052] Specifically, such as Figure 6 As shown, the vehicle's gravity torque is determined based on the vehicle's center of gravity position G and its lever arm vector relative to a preset rotation axis. The direction is along the negative y-axis, which is the preset rotation axis, i.e., the position where the leading edge of the track contacts the ground.
[0053] The drilling rig anti-tipping early warning method provided in this embodiment uses a dual-axis tilt sensor to obtain the first and second tilt angles of the vehicle body in the tilt direction, thereby determining the vehicle body tilt rotation matrix, and then obtaining the homogeneous transformation matrix of the vehicle body and the direction vector from the center of gravity of the vehicle body to the rotation axis (i.e., the gravity lever vector). Combined with the vehicle body gravity, the vehicle body gravity matrix is determined, and the gravity moment under the tilt state of the vehicle body is accurately quantified, providing reliable vehicle body-end data support for subsequent comparison with the boom gravity moment and assessment of the drilling rig overturning risk.
[0054] Step S203: Use the second sensor to acquire the posture of each joint, and determine the pose transformation matrix of each joint relative to the previous joint based on the posture of each joint and the posture of the vehicle body.
[0055] Specifically, the second sensor is an angle or length sensor, and the posture of each joint includes: joint angle or joint length. Step S203 above includes: Step S2031: Determine the vehicle's center of gravity posture based on the vehicle's body posture, and determine the pose transformation matrix of the first joint relative to the vehicle body based on the vehicle's center of gravity posture and the joint posture of the first joint connected to the vehicle body.
[0056] Specifically, each joint is equipped with an angle or length sensor, which can acquire the angle or length of each joint. Figure 2 Taking five joints as an example, the sensor values detected by each joint are a1, a2, a3, a4, and a5, respectively. For the first joint connected to the vehicle body, the preceding joint is the vehicle body. According to step S2022, the pose matrix of the vehicle body's center of gravity under the first and second tilt angles is... The coordinates of its center of gravity are [x, y, z]. Therefore, the pose transformation matrix of the first joint position relative to the vehicle's center of gravity is: Let the matrix at the connection point between the vehicle's center of gravity and the first joint be... This matrix is a fixed matrix. The matrix at the connection point of the first joint relative to the vehicle body can be used to obtain the DH parameters based on the DH model. ,in, Indicates the length of the connecting rod, Indicates the torsion angle of the connecting rod, Indicates joint offset, The joint angle of the first joint can be represented by the matrix obtained from the DH parameters. The pose transformation matrix of the first joint position relative to the vehicle's center of gravity .
[0057] Step S2032: Based on the DH model of the boom and the posture of each joint, determine the pose transformation matrix of the remaining joints (excluding the first joint) relative to the previous joint.
[0058] Specifically, the Denavit-Hartenberg (DH) model is a classic method in robotics used to describe the relative positional relationships between joints and links, defining the pose of each joint using four parameters. Combining the DH model of the boom and the poses of each joint a1, a2, a3, a4, and a5, the pose transformation matrices of the remaining joints (excluding the first joint) relative to the previous joint are determined: , , , The specific determination process is based on mature existing technology and will not be elaborated here.
[0059] Step S204: Obtain the gravity of each joint, and calculate the boom gravity matrix based on the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix.
[0060] Specifically, step S204 includes: Step S2041: Based on the vehicle's center of gravity coordinates, the center of gravity transformation matrix of each joint, and the corresponding pose transformation matrix, determine the center of gravity pose of each joint in sequence.
[0061] Specifically, using the 3D model created with Solidworks software, the position of each joint (the connection point to the end of the link of the previous joint) can be determined as (x1, y1, z1), and the position of the center of gravity of the link can be denoted as (x2, y2, z2). The center of gravity of the link is consistent with the attitude matrix of the end of the link, so the positional relationship of the center of gravity transformation matrix is [x2-x1, y2-y1, z2-z1]. The attitude matrix does not change. Based on this process, the center of gravity transformation matrix of each joint can be determined: , , , , Based on the vehicle's center of gravity coordinates The centroid transformation matrix of each joint and the corresponding pose transformation matrix ( , , , , The process of determining the center of gravity position of each joint in sequence includes: The center of gravity position of the first joint: ; The center of gravity position of the second joint: ; The center of gravity position of the third joint: ; The center of gravity position of the fourth joint: ; The center of gravity position of the fifth joint: .
[0062] Step S2042: Determine the center of gravity position vector of each joint based on the center of gravity pose of each joint, and determine the gravity matrix of each joint in combination with the gravity of each joint.
[0063] Specifically, the center of gravity pose of each joint is represented as follows: It contains the position matrix of the centroids of each joint. Given the pose matrix R, the center-of-gravity position vector of each joint is selected based on the center-of-gravity pose of each joint: , , , , ,like Figure 6 As shown, the gravity matrix of each joint is obtained by combining the gravity of each joint: the gravity matrix of the first joint is... The gravity matrix of the second joint is Gravity matrix of the third joint The gravity matrix of the fourth joint Gravity matrix of the fifth joint .
[0064] like Figure 6 In this diagram, the first tilt angle is the vehicle's forward and backward tilt angle, and the second tilt angle is the vehicle's left and right tilt angle, used to determine the vehicle's attitude. The vehicle's attitude relative to the ground can be represented as (α, β, 0). The attitude can be represented by three angles: RPY. Each tilt angle is α, the second tilt angle is β, and the third tilt angle is the heading angle, which is 0 here (because the coordinate system always points x in the direction of vehicle movement, hence 0).
[0065] Step S2043: Add the gravity matrices of each joint to obtain the boom gravity matrix.
[0066] Specifically, the gravity matrices of each joint are added together to obtain the boom gravity matrix: ,in, , , , , These represent the weights of the first joint (drill arm swing joint), the second joint (drill arm pitch joint), the third joint (drill frame pitch joint), the fourth joint (drill frame swing joint), and the fifth joint (drill frame compensation joint, including the power head on it). In this embodiment, it is assumed that the weights of each joint are known.
[0067] The drilling rig anti-tipping early warning method provided in this embodiment uses angle or length sensors to obtain joint postures such as joint angles or lengths. Combined with the vehicle body posture, the pose transformation matrix of each joint relative to the previous joint is determined. Based on the vehicle's center of gravity coordinates, the center of gravity transformation matrix of each joint, and the pose transformation matrix, the center of gravity posture of each joint is determined. Then, combined with the gravity of each joint, the gravity matrix of each joint is obtained. This accurately obtains the relevant data of the pose and gravitational moment of each joint of the boom, providing accurate boom-end data for subsequent assessment of drilling rig overturning risk and improving the accuracy of hazard judgment.
[0068] Step S205: Calculate the risk factor based on the boom gravity matrix and the vehicle gravity matrix, and issue an overturning warning for the target drilling rig based on the risk factor.
[0069] Specifically, step S205 includes: Step S2051: Divide the boom gravity matrix by the vehicle gravity matrix to obtain the hazard factor. The hazard factor is approximately in the range of (-1, 1), because when the overturning moment equals the gravitational moment, the overturning risk at a specific height of the vehicle body is determined. Specifically, since the vehicle gravity matrix provides basic support for the stability of the drilling rig, while the boom gravity matrix interferes with the balance and stability of the drilling rig, their effects on vehicle body stability are essentially opposite. Therefore, the hazard factor can be calculated by dividing the boom gravity matrix by the vehicle gravity matrix. .
[0070] Step S2052: Based on the risk factor and its range, determine the early warning strategy. The smaller the difference between the risk factor and -1, the greater the possibility of the target drilling rig overturning.
[0071] Specifically, if the risk factor is negative, it means the boom gravity matrix and the vehicle gravity matrix are in opposite directions. The boom gravity matrix has the effect of causing the vehicle to rotate. When the risk factor is close to -1, it indicates that the target drilling rig has a high risk of overturning, and an alarm should be issued to remind the operators. In practical applications, a risk factor threshold can be set based on experience. When the risk factor reaches this threshold, an alarm is issued. Different risk levels can also be divided according to the magnitude of the risk factor, and different alarm levels can be set accordingly. This is just an example, but not a limitation. If the risk factor is positive, it means the boom gravity matrix and the vehicle gravity matrix are in the same direction. The boom gravity matrix has no side effect on the stability of the vehicle, and the boom can be in a folded state. It should be noted that the risk factor threshold can be determined not only based on experience but also through calibration or simulation testing. For example, on a 5-degree slope, what state of the five-joint boom is considered dangerous? The overturning value corresponding to this value can be used as the alarm value. If it continues to increase, the danger increases, and this value can be set as the danger value. This is just an example, but not a limitation.
[0072] In practical applications, in addition to calculating the risk factor of forward overturning, the torque of the drilling rig boom to both sides (left or right) can be calculated according to the method described in this embodiment, and it can be determined whether there is a risk of overturning to the left or right. A comprehensive judgment and early warning can be made in combination with the risk of forward overturning.
[0073] The drilling rig anti-tipping early warning method provided in this embodiment obtains the risk coefficient by dividing the boom gravity matrix by the vehicle gravity matrix, and then issues an early warning based on the risk coefficient. This accurately quantifies the degree of overturning risk of the drilling rig, allowing operators to clearly understand the risk status of the equipment and take timely countermeasures. This effectively reduces the probability of overturning accidents during drilling operations, ensures equipment safety and the personal safety of operators, and reduces losses such as equipment damage and project delays caused by overturning.
[0074] In some alternative implementations, the method further includes: Step S206: If the target drilling rig is in motion, the speed sensor is used to obtain the vehicle speed and / or boom speed, and the influencing factor is determined based on the vehicle speed and / or boom speed.
[0075] Specifically, the aforementioned analysis is a torque analysis of the vehicle body and boom in a stationary or quasi-stationary state. If the target drilling rig is in motion, an approximate influencing factor can be obtained based on the vehicle body speed and / or boom speed. The influence of uphill and downhill slopes has already been incorporated into the vehicle's attitude. The front and rear tilt angles and left and right tilt angles measured by the dual-axis tilt sensors of the vehicle body take into account the uphill and downhill slopes. η is a correction factor for the influence of vehicle speed and boom speed, which needs to be determined based on actual calibration. This calibration process is a mature existing technology and will not be elaborated here.
[0076] Step S207: Based on the influence factor, calculate the boom gravity matrix according to the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix.
[0077] Specifically, the boom gravity matrix is calculated using approximate simulation based on approximate influence factors: After obtaining the boom gravity matrix, the risk factor is calculated based on the boom gravity matrix and the vehicle gravity matrix. This process has been described in detail in step S205 and will not be repeated here.
[0078] The drilling rig anti-tipping early warning method provided in this embodiment analyzes the vehicle speed and / or boom speed under motion, fully considering the influence of speed on boom gravity torque under motion, making the calculation of boom gravity matrix more consistent with actual working conditions, making the calculation of risk factors and overturning early warning more accurate in subsequent motion, effectively improving the accuracy of overturning risk assessment of drilling rigs during dynamic operation, and better protecting equipment and personnel safety.
[0079] This embodiment also provides a drilling rig anti-overturning early warning system, which is used to implement the above embodiments and preferred embodiments, and will not be repeated as already described. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the system described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.
[0080] The drilling rig anti-tipping early warning system provided in this embodiment includes a fixed vehicle body and a boom connected by multiple movable joints. A first sensor is installed on the vehicle body; second sensors are installed on each joint, such as... Figure 7 As shown, the system includes: The coordinate system establishment module 701 is used to establish a three-dimensional coordinate system based on the three-dimensional model of the target drilling rig, and to obtain the coordinates of the vehicle's center of gravity and the joint center of gravity transformation matrix of each joint relative to that joint in the three-dimensional coordinate system.
[0081] The vehicle gravity matrix determination module 702 is used to acquire the vehicle attitude using the first sensor and determine the vehicle gravity matrix based on the vehicle attitude, the vehicle center of gravity coordinates, and the vehicle gravity.
[0082] The joint posture determination module 703 is used to acquire the posture of each joint using the second sensor, and to determine the pose transformation matrix of each joint relative to the previous joint based on the posture of each joint and the posture of the vehicle body.
[0083] The boom gravity matrix determination module 704 is used to obtain the gravity of each joint and calculate the boom gravity matrix based on the gravity of each joint, the joint center of gravity transformation matrix and the pose transformation matrix.
[0084] The hazard warning module 705 is used to calculate the hazard coefficient based on the boom gravity matrix and the vehicle gravity matrix, and to provide an overturning warning for the target drilling rig based on the hazard coefficient.
[0085] In some alternative implementations, the coordinate system establishment module 701 includes: The coordinate acquisition unit is used to acquire the coordinates of the vehicle's center of gravity, the coordinates of each joint, and the coordinates of the center of gravity of each joint in the three-dimensional coordinate system.
[0086] The coordinate transformation unit is used to determine the joint centroid transformation matrix of each joint based on the joint coordinates and the corresponding joint centroid coordinates.
[0087] In some alternative implementations, the vehicle gravity matrix determination module 702 includes: The vehicle body rotation matrix calculation unit is used to determine the rotation matrix of the vehicle body tilt based on the first tilt angle and the second tilt angle of the vehicle body tilt direction.
[0088] The vehicle center of gravity position determination unit is used to determine the homogeneous transformation matrix of the vehicle body according to the rotation matrix, and to determine the lever arm vector of the vehicle center of gravity coordinates relative to a preset rotation axis based on the homogeneous transformation matrix.
[0089] The vehicle gravity matrix calculation unit is used to determine the gravity torque of the vehicle body based on the coordinates of the vehicle's center of gravity and its lever arm vector with respect to a preset rotation axis.
[0090] In some alternative implementations, the joint pose determination module 703 includes: The first transformation matrix determination unit is used to determine the vehicle body center of gravity posture based on the vehicle body posture, and to determine the pose transformation matrix of the first joint relative to the vehicle body based on the vehicle body center of gravity posture and the joint posture of the first joint connected to the vehicle body.
[0091] The first transformation matrix determination unit is used to determine the pose transformation matrix of the remaining joints (excluding the first joint) relative to the previous joint by combining the DH model of the boom and the posture of each joint.
[0092] In some alternative implementations, the boom gravity matrix determination module 704 includes: The joint center of gravity pose determination unit is used to determine the center of gravity pose of each joint sequentially based on the vehicle's center of gravity coordinates, the center of gravity transformation matrix of each joint, and the corresponding pose transformation matrix.
[0093] The joint torque calculation unit is used to determine the center of gravity position vector of each joint based on the center of gravity pose of each joint, and to determine the gravity matrix of each joint in combination with the gravity of each joint.
[0094] The joint torque summation unit is used to add up the gravity matrices of each joint to obtain the boom gravity matrix.
[0095] In some alternative implementations, the hazard warning module 705 includes: The hazard factor calculation unit is used to divide the boom gravity matrix by the vehicle gravity matrix to obtain the hazard factor, which ranges from (-1, 1).
[0096] The overturning early warning unit is used to determine the early warning strategy based on the risk factor and its range. The smaller the difference between the risk factor and -1, the greater the possibility of the target drilling rig overturning.
[0097] In some alternative implementations, the system further includes: The influence factor determination module 706 is used to obtain the vehicle speed and / or boom speed using speed sensors if the target drilling rig is in motion, and to determine the influence factor based on the vehicle speed and / or boom speed.
[0098] The boom gravity matrix dynamic calculation module 707 is used to calculate the boom gravity matrix based on the influence factors, the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix.
[0099] Further functional descriptions of the above modules and units are the same as those in the corresponding embodiments described above, and will not be repeated here.
[0100] In this embodiment, the drilling rig anti-overturning early warning system is presented in the form of functional units. Here, a unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.
[0101] This invention also provides a computer device having the above-described features. Figure 7 The drilling rig anti-overturning early warning system shown.
[0102] Please see Figure 8 , Figure 8This is a schematic diagram of the structure of a computer device provided in an optional embodiment of the present invention, such as... Figure 8 As shown, the computer device includes one or more processors 10, memory 20, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components communicate with each other via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processors can process instructions executed within the computer device, including instructions stored in or on memory to display graphical information of a GUI on external input / output devices (such as display devices coupled to the interfaces). In some alternative implementations, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 8 Take a processor 10 as an example.
[0103] Processor 10 may be a central processing unit, a network processor, or a combination thereof. Processor 10 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GPA), or any combination thereof.
[0104] The memory 20 stores instructions executable by at least one processor 10 to cause the at least one processor 10 to perform the method shown in the above embodiments.
[0105] The memory 20 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computer device. Furthermore, the memory 20 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory 20 may optionally include memory remotely located relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.
[0106] The memory 20 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 20 may also include a combination of the above types of memory.
[0107] The computer device also includes a communication interface 30 for communicating with other devices or communication networks.
[0108] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.
[0109] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and all such modifications and variations fall within the scope defined by the appended claims.
Claims
1. A method for preventing overturning of a drilling rig, the drilling rig comprising: A fixed vehicle body and a boom cascaded through multiple movable joints, characterized in that a first sensor is mounted on the vehicle body; and a second sensor is mounted on each joint, the method comprising: A three-dimensional coordinate system is established based on the three-dimensional model of the target drilling rig, and the coordinates of the vehicle's center of gravity and the transformation matrix of the center of gravity of each joint relative to that joint are obtained in the three-dimensional coordinate system. The vehicle body attitude is acquired using the first sensor, and the vehicle gravity matrix is determined based on the vehicle body attitude, the vehicle center of gravity coordinates, and the vehicle gravity. The second sensor is used to acquire the posture of each joint, and the pose transformation matrix of each joint relative to the previous joint is determined based on the posture of each joint and the posture of the vehicle body. Obtain the gravity of each joint, and calculate the boom gravity matrix based on the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix; The risk factor is calculated based on the boom gravity matrix and the vehicle gravity matrix, and an overturning warning is issued for the target drilling rig based on the risk factor.
2. The method according to claim 1, characterized in that, One axis of the three-dimensional coordinate system is the rotation axis for vehicle body tilt. Obtaining the coordinates of the vehicle's center of gravity and the joint center of gravity transformation matrix of each joint relative to that joint in the three-dimensional coordinate system includes: Based on the three-dimensional coordinate system, obtain the coordinates of the vehicle's center of gravity, the coordinates of each joint, and the coordinates of the center of gravity of each joint in the three-dimensional coordinate system. Based on the coordinates of each joint and the corresponding coordinates of the joint centroid, determine the centroid transformation matrix of each joint.
3. The method according to claim 1, characterized in that, The first sensor is a dual-axis tilt sensor, and the vehicle attitude includes: the vehicle tilt direction, a first tilt angle and a second tilt angle in the vehicle tilt direction; The vehicle gravity matrix is determined based on the vehicle attitude, vehicle center of gravity coordinates, and vehicle gravity, including: The rotation matrix for vehicle tilt is determined based on the first and second tilt angles in the vehicle tilt direction; The homogeneous transformation matrix of the vehicle body is determined based on the rotation matrix, and the lever arm vector of the vehicle's center of gravity coordinates relative to the preset rotation axis is determined based on the homogeneous transformation matrix. The gravitational torque of the vehicle body is determined based on the coordinates of the vehicle's center of gravity and its lever arm vector relative to the preset rotation axis.
4. The method according to claim 3, characterized in that, The second sensor is an angle or length sensor, and the postures of each joint include: joint angle or joint length; Based on the posture of each joint and the vehicle body posture, determine the pose transformation matrix of each joint relative to the previous joint, including: The vehicle body posture is determined based on the vehicle body posture, and the pose transformation matrix of the first joint relative to the vehicle body is determined based on the vehicle body posture and the joint posture of the first joint connected to the vehicle body. By combining the DH model of the boom and the posture of each joint, the pose transformation matrix of the remaining joints (excluding the first joint) relative to the previous joint is determined.
5. The method according to claim 1, characterized in that, The boom gravity matrix is calculated based on the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix, including: Based on the vehicle's center of gravity coordinates, the center of gravity transformation matrix of each joint, and the corresponding pose transformation matrix, the center of gravity pose of each joint is determined sequentially. The center of gravity position vector of each joint is determined based on the center of gravity pose of each joint, and the gravity matrix of each joint is determined by combining the gravity of each joint. The gravity matrices of each joint are added together to obtain the gravity matrix of the boom.
6. The method according to claim 1, characterized in that, The risk factor is calculated based on the boom gravity matrix and the vehicle gravity matrix, and an overturning warning is issued for the target drilling rig based on the risk factor, including: Divide the boom gravity matrix by the vehicle gravity matrix to obtain the risk coefficient, which is in the range of (-1, 1). Based on the risk coefficient and its range, an early warning strategy is determined. The smaller the difference between the risk coefficient and -1, the greater the likelihood that the target drilling rig will overturn.
7. The method according to any one of claims 1 to 6, characterized in that, The method further includes: If the target drilling rig is in motion, the speed sensor is used to obtain the vehicle speed and / or boom speed, and the influencing factor is determined based on the vehicle speed and / or boom speed. Based on the aforementioned influencing factors, the boom gravity matrix is calculated according to the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix.
8. A drilling rig anti-tipping early warning system, the drilling rig comprising: A fixed vehicle body and a boom cascaded through multiple movable joints, characterized in that a first sensor is mounted on the vehicle body; and a second sensor is mounted on each joint, the system comprising: The coordinate system establishment module is used to establish a three-dimensional coordinate system based on the three-dimensional model of the target drilling rig, and to obtain the coordinates of the vehicle's center of gravity and the joint center of gravity transformation matrix of each joint relative to that joint in the three-dimensional coordinate system. The vehicle gravity matrix determination module is used to acquire the vehicle attitude using the first sensor, and determine the vehicle gravity matrix based on the vehicle attitude, the vehicle center of gravity coordinates, and the vehicle gravity. The joint posture determination module is used to acquire the posture of each joint using the second sensor, and to determine the pose transformation matrix of each joint relative to the previous joint based on the posture of each joint and the posture of the vehicle body. The boom gravity matrix determination module is used to obtain the gravity of each joint and calculate the boom gravity matrix based on the gravity of each joint, the joint center of gravity transformation matrix, and the pose transformation matrix. The hazard warning module is used to calculate the hazard coefficient based on the boom gravity matrix and the vehicle gravity matrix, and to provide an overturning warning for the target drilling rig based on the hazard coefficient.
9. A computer device, characterized in that, include: A memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, the processor executing the computer instructions to perform the method of any one of claims 1 to 7.
10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the method of any one of claims 1 to 7.