Excavator mechanical arm motion calibration method, device, electronic equipment and storage medium

Abstract

The present application provides a method, device, electronic device, and storage medium for calibrating the motion of an excavator manipulator arm. The method comprises: obtaining corresponding joint angle information and first arm displacement information of an initial excavator in at least three different postures; determining a calibration angle conversion equation based on the joint angle information; determining a manipulator arm calibration equation based on the first arm displacement information and the calibration angle conversion equation; determining a universal calibration model based on the calibration angle conversion equation and the manipulator arm calibration equation; determining corresponding joint angle information and first arm displacement information of a target excavator in at least three different postures, and calibrating the target excavator using the universal calibration model based on the joint angle information and first arm displacement information of the target excavator; wherein the calibration angle conversion equation and the manipulator arm calibration model are calibrated and calculated according to a preset optimization function.

Description

Technical Field

[0001] The present application relates to the field of excavator control technology, and in particular to an excavator mechanical arm motion calibration method, device, electronic equipment and storage medium. Background Art

[0002] Nowadays, the automation or semi-automatic transformation of excavators has become a hot research and development topic in the engineering machinery industry. In order to realize tasks such as automated excavation, remote operation of excavators, or visual auxiliary operation of excavator manipulator arms, the kinematic modeling of excavator manipulator arms is the primary prerequisite for automated intelligent control of excavator manipulator arms. Usually, the modeling of excavator manipulator arms requires accurate three-dimensional structural models of the large and small arms. The acquisition of these three-dimensional models requires close cooperation with excavator manufacturers. However, data errors may be introduced during the processing and equipment of excavators due to the assembly of parts. Therefore, the three-dimensional structural model provided by the manufacturer may not be completely consistent with the actual excavator structure. Among them, the large arm of the excavator is usually curved (such as Figure 1 This makes measuring the 3D model cumbersome and prone to modeling errors. Furthermore, due to the wide variety of excavators, each with its own unique robotic arm, a single calibration model cannot be applied to all. Developing separate calibration models for different excavator types increases R&D costs and leads to incompatibility during application. Summary of the Invention

[0003] In view of this, the purpose of this application is to propose an excavator mechanical arm motion calibration method, device, electronic equipment and storage medium.

[0004] Based on the above objectives, the present application provides a method for calibrating motion of an excavator mechanical arm, comprising:

[0005] Obtaining corresponding joint angle information, first arm displacement information, and second arm displacement information of the initial excavator in at least three different postures;

[0006] Determining a calibration angle conversion equation according to the joint angle information;

[0007] Determining a robotic arm calibration equation based on the first arm displacement information, the second arm displacement information, and the calibration angle conversion equation;

[0008] Determine the corresponding joint angle information and first arm displacement information of the target excavator in at least three different postures, and calibrate the target excavator through the manipulator calibration model based on the joint angle information and first arm displacement information of the target excavator; wherein the calibration angle conversion equation and the manipulator calibration model are calibrated and calculated according to a preset optimization function.

[0009] Based on the same concept, the present application also provides an excavator mechanical arm motion calibration device, comprising:

[0010] an acquisition module configured to acquire corresponding joint angle information and first arm displacement information of the initial excavator in at least three different postures;

[0011] a first determining module, configured to determine a calibration angle conversion equation according to the joint angle information;

[0012] a second determining module, configured to determine a robotic arm calibration equation based on the first arm displacement information and the calibration angle conversion equation;

[0013] The calibration module is configured to determine the corresponding joint angle information and first arm displacement information of the target excavator in at least three different postures, and calibrate the target excavator through the manipulator calibration model based on the joint angle information and first arm displacement information of the target excavator; wherein the manipulator calibration model performs calibration calculation according to a preset optimization function.

[0014] Based on the same concept, the present application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and runnable on the processor. When the processor executes the program, the excavator mechanical arm motion calibration method as described in any one of the above items is implemented.

[0015] Based on the same concept, the present application also provides a non-transitory computer-readable storage medium, which stores computer instructions, and the computer instructions are used to enable the computer to implement the excavator mechanical arm motion calibration method as described in any one of the above items.

[0016] From the above, it can be seen that the excavator manipulator arm motion calibration scheme provided by the present application first determines the excavator cabin of the excavator, the connection points of the excavator's main arm and forearm, and the connection points of the forearm and the bucket, and measures through the inclination sensors set on different joints to determine the joint angle information of each part of the excavator, and converts the equation according to the joint angle information and the calibration angle of the excavator; further, the displacement information of the end of the first arm is obtained, and further, the manipulator arm calibration equation is determined according to the displacement information of the first arm and the calibration angle conversion equation; then, when calibrating any excavator through the manipulator arm calibration equation, the excavator can be calibrated by only obtaining the joint angle information of the excavator (that is, the measurement angle of the inclination sensor) and the displacement information of the first arm, thereby determining the conversion parameters of the excavator and the length of the excavator's main arm and the excavator's main arm. The present application determines a calibration model by determining the relationship between the excavator's mechanical arm and the angle, so that the calibration model is applicable to different models of excavators. When using the calibration model to calibrate the relevant parameters of the excavator, there is no need to obtain the precise three-dimensional structure of the excavator arm, and the accuracy of the calibration results can also be guaranteed. Therefore, the present application effectively solves the problem in the prior art that the calibration model relies on a three-dimensional model and has low practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in this application or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are merely embodiments of this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 This is a schematic diagram of an excavator model according to an embodiment of the present application.

[0019] Figure 2 This is a flow chart of the excavator arm motion calibration method according to an embodiment of the present application.

[0020] Figure 3 This is a schematic diagram of the straight-rod excavator mechanical arm according to an embodiment of the present application.

[0021] Figure 4 Schematic diagram of the excavator arm motion calibration device according to an embodiment of the present application.

[0022] Figure 5 This is a schematic diagram of the installation position of the laser rangefinder according to an embodiment of the present application.

[0023] Figure 6 This is a schematic diagram of the structure of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of this application more clear, this application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0025] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should have the usual meanings understood by people with ordinary skills in the field to which this application belongs. The "first", "second" and similar words used in the embodiments of the present application do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0026] As mentioned in the background technology section, the kinematic modeling of the excavator arm is the primary prerequisite for the automated intelligent control of the excavator arm. Usually, the kinematic modeling of the excavator arm requires an accurate three-dimensional structural model of the excavator arm. However, the three-dimensional structural model of the excavator arm is generally mastered by the excavator manufacturer and is usually difficult to obtain. In addition, the excavator's general arm is curved (refer to Figure 1 Excavator models), measuring 3D models is cumbersome and prone to modeling errors. Furthermore, due to the diversity of excavators, different excavator arms have different mechanical arms. This means that a single calibration model cannot be applied to all excavators. Different calibration models must be developed for different excavator arms. The development of multiple calibration models can lead to increased R&D costs and incompatibility during application.

[0027] In view of the above actual situation, the embodiment of the present application proposes a motion calibration scheme for an excavator mechanical arm. First (eg Figure 2 As shown in the figure, the excavator cabin, the connection points of the excavator's boom and arm, and the connection points of the arm and bucket are determined. According to the above connection points, a straight rod model of the excavator is constructed, that is, the boom and arm of the excavator are regarded as straight lines, that is, the boom and arm are as follows: Figure 3As shown in the figure, OA and AB are measured by inclination sensors arranged on different joints under the straight rod model to determine the joint angle information of each part of the excavator, and the calibration angle conversion equation of the angle to be calibrated (the angle between the parts of the excavator) is determined according to the triangular relationship between the joint angle information and the excavator's main arm and forearm; further, the displacement information of the first arm and the second arm is obtained, and further, the mechanical arm calibration equation is determined according to the displacement information of the first arm and the second arm and the calibration angle conversion equation; and then, a universal calibration model is determined according to the calibration angle conversion equation and the mechanical arm calibration equation. After the universal calibration model is determined, when calibrating any excavator through the universal calibration model, the excavator can be calibrated by only obtaining the joint angle information of the excavator (i.e., the measurement angle of the inclination sensor), the displacement information of the first arm and the displacement information of the second arm, thereby determining the conversion parameters of the excavator and the length of the excavator's large and small arms. This application determines the calibration model by straightening the excavator's mechanical arm, so that the calibration model is applicable to different models of excavators. When using the calibration model to calibrate the relevant parameters of the excavator, there is no need to obtain the precise three-dimensional structure of the excavator arm, and the accuracy of the calibration results can also be guaranteed. Therefore, this application effectively solves the problem in the existing technology that the calibration model relies on the three-dimensional model and has low practicality.

[0028] In view of this, embodiments of the present application provide a method, device, electronic device, and storage medium for calibrating the motion of an excavator mechanical arm.

[0029] like Figure 3 FIG. 1 is a flow chart of a method for calibrating the motion of an excavator mechanical arm proposed in this application, which specifically includes:

[0030] Step 302: Obtain corresponding joint angle information and first arm displacement information of the initial excavator in at least three different postures;

[0031] Step 304: determining a calibration angle conversion equation based on the joint angle information;

[0032] Step 306: Determine a robotic arm calibration equation based on the first arm displacement information and the calibration angle conversion equation;

[0033] Step 308: Determine the corresponding joint angle information and first arm displacement information of the target excavator in at least three different postures, and calibrate the target excavator through the manipulator calibration model based on the joint angle information and first arm displacement information of the target excavator; wherein the calibration angle conversion equation and the manipulator calibration model are calibrated and calculated according to a preset optimization function.

[0034] Figure 2A straight-rod schematic diagram of determining a universal calibration model according to an embodiment of the present application is shown.

[0035] Regarding step 302, the excavator includes a first arm, a second arm, a bucket, and a cabin. Before obtaining the joint angle information, the first arm displacement information, and the second arm displacement information of the excavator, the excavator is firstly Figure 2 As shown in the straight rod, the arm and forearm of the initial excavator are regarded as straight lines, that is, the arm and forearm are as follows Figure 2 OA and AB shown, the initial excavator bucket and arm are as follows Figure 2 Furthermore, the "initial excavator" in this step refers to the excavator used to construct the universal calibration model. The "initial" is only used to distinguish it from the "target" in the "target excavator" in step 310 and has no practical meaning. It does not represent any state change of the excavator. Moreover, the initial excavator can be any excavator and does not refer to any specific excavator.

[0036] In step 302, the joint angle information is the angle information measured by the inclination sensors installed at different positions of the excavator, wherein each inclination sensor is used to measure the inclination angle of the part where the inclination sensor is installed relative to the horizontal plane, and accurate measurement can be achieved. Furthermore, the "three different postures" in this step can be understood as different states of the excavator's mechanical arm or the inclination angle of the excavator's main body relative to the horizontal plane. Of course, the different states can also be different states of the excavator's cabin or different states of the excavator's bucket, all of which can be considered as different postures. Furthermore, the first arm displacement information is related information about the displacement of the excavator's forearm, and the second arm displacement information is related information about the displacement of the excavator's boom. Of course, in some embodiments, the first arm can be a boom, and the second arm can also be a forearm. The first arm and the second arm in this application are only used to distinguish between the boom and the forearm, and do not mean that the forearm must be the first arm, the boom must be the second arm, or the boom must be the first arm, and the forearm must be the second arm.

[0037] In this step, the calibration angle information includes: a first calibration angle, a second calibration angle, and a third calibration angle. Specifically, the first calibration angle is the angle between the initial excavator's boom and the cabin, that is, Figure 2 The angle AOC shown in FIG; The second calibration angle is the angle between the initial excavator arm and the arm, that is, Figure 2 The third calibration angle is the angle between the initial excavator arm and the bucket, that is, Figure 2 The angle ABH shown in .

[0038] Furthermore, in step 302, the first arm displacement information may be the displacement information of the coordinates of the connection point between the forearm and the initial excavator bucket, and the second arm displacement information may be the displacement information of the coordinates of the connection point between the upper arm and the forearm. Any change of the upper and lower arms will produce displacement. By using displacement information instead of position information, the measuring device does not need to know the conversion relationship between the global coordinate system of the measuring device and the cockpit coordinate system. It only needs to determine the measured position difference along the x-axis and z-axis (i.e., the horizontal plane and the vertical plane) of the cockpit coordinate system. Specifically, as Figure 2 The dotted line from point B to point E shown in the figure may be the displacement information of the end of the initial excavator arm. When the end of the arm is displaced, the connection point between the boom and the arm, that is, point A, is also relatively displaced.

[0039] In some optional embodiments, in step 302, corresponding joint angle information, first arm displacement information, and second arm displacement information of the initial excavator in at least three different postures are obtained. The excavator's boom, arm, bucket, and cabin are all equipped with tilt sensors, and the tilt sensors of the boom, arm, and cabin are denoted as T1, T2, T3, and T4, respectively.

[0040] In some optional embodiments, the joint angle information is represented as measurement information of T1, T2, T3, and T4, including: a first measurement angle, a second measurement angle, a third measurement angle, and a fourth measurement angle. For ease of calculation, the first measurement angle, the second measurement angle, the third measurement angle, and the fourth measurement angle are respectively recorded as θ1, θ2, θ3, and θ4. Specifically, the first measurement angle, the second measurement angle, the third measurement angle, and the fourth measurement angle are respectively the measurement values ​​of the inclination sensor installed on the boom of the excavator, the measurement values ​​of the inclination sensor installed on the arm of the initial excavator, the measurement values ​​of the inclination sensor installed on the bucket of the initial excavator, and the measurement values ​​of the inclination sensor installed on the cabin of the initial excavator. Specifically, the above four inclination sensors are respectively installed in parallel on the surfaces of the boom, arm, bucket, and cabin of the initial excavator. Of course, they can also be installed in any other suitable place, such as the top of the excavator cabin.

[0041] In some alternative embodiments, the inclinometer is rigidly mounted to the surface of the excavator's boom, arm, bucket, and cabin. Of course, in some alternative embodiments, the inclinometer can be fixed to the excavator's measured location using other fixing methods to achieve measurement of that location. For example, it can be fixed using removable bolts, nuts, or other means.

[0042] In some optional embodiments, the first arm displacement information can be determined by the following steps: first, obtaining the height of the forearm, the horizontal position difference of the forearm, the height displacement difference of the forearm, and the horizontal displacement difference of the forearm of the initial excavator in at least three different postures; and determining the displacement information of the forearm based on the height of the forearm, the horizontal position difference of the forearm, the height displacement difference of the forearm, and the horizontal displacement difference of the forearm.

[0043] In some optional embodiments, the second arm displacement information can be determined by the following steps: obtaining the height of the boom of the initial excavator, the horizontal position difference of the boom, the height displacement difference of the boom, and the horizontal displacement difference of the boom in at least three different postures of the initial excavator; and determining the displacement information of the boom based on the height of the boom, the horizontal position difference of the boom, the height displacement difference of the boom, and the horizontal displacement difference of the boom.

[0044] Furthermore, the calibration angle conversion equation includes: a first calibration angle, a second calibration angle and a third calibration angle; determining the calibration angle information according to the joint angle information specifically includes: (1) determining a first conversion parameter, determining the first calibration angle according to the measurement angle of the inclination sensor set on the excavator boom, the measurement angle of the inclination sensor set on the excavator cabin and the first conversion parameter; (2) determining a second conversion parameter, determining the second calibration angle according to the measurement angle of the inclination sensor set on the excavator boom, the measurement angle of the inclination sensor set on the excavator arm and the second conversion parameter; (3) determining a third conversion parameter, determining the third calibration angle according to the measurement angle of the inclination sensor set on the excavator arm, the measurement angle of the inclination sensor set on the excavator bucket and the third conversion parameter; determining the calibration angle conversion equation according to the first calibration angle, the second calibration angle and the third calibration angle.

[0045] Specifically, the first conversion parameter and the second conversion parameter in step 304 can be determined by the following steps: obtaining the first measurement angle, the second measurement angle, the fourth measurement angle, and the horizontal axis coordinate and the vertical axis coordinate corresponding to the joint point of the first arm of the initial excavator in the first posture, and determining the first residual term based on the first measurement angle, the second measurement angle, the fourth measurement angle, and the horizontal axis coordinate and the vertical axis coordinate corresponding to the joint point of the first arm of the initial excavator; obtaining the first measurement angle, the second measurement angle, the fourth measurement angle, and the horizontal axis coordinate and the vertical axis coordinate corresponding to the joint point of the second arm of the initial excavator in the second posture, and determining the second residual term based on the first calibration angle, the second calibration angle, the fourth measurement angle, and the horizontal axis coordinate and the vertical axis coordinate corresponding to the joint point of the second arm of the initial excavator; determining the optimization objective function based on the first residual term and the second residual term; and determining the first conversion parameter and the second conversion parameter based on the optimization objective function. In some embodiments, the first measurement angle, the second measurement angle, the third measurement angle and the fourth measurement angle may not be the measurement values ​​of the inclination sensors installed on the second arm, the first arm, the bucket and the cabin, but may be the measurement values ​​of the inclination sensors installed on the bucket, the cabin, the first arm and the second arm respectively. The first and second are only used to distinguish between the upper arm and the lower arm and have no practical meaning.

[0046] In some optional embodiments, according to the above method and Figure 2 As shown, the first calibration angle, the second calibration angle and the third calibration angle can be determined by the following trigonometric function conversion relationship. Figure 2 As shown, the connection point between the excavator arm and the excavator cabin is o, the connection point between the excavator arm and the excavator arm is A, and the connection point between the excavator arm and the excavator bucket is B. Based on the displacement information that can be determined by moving the initial excavator arm and the excavator arm, the following is constructed: Figure 2 The straight arm model shown in the figure is used to determine the angle between the excavator arm and the excavator cabin. That is the first calibration angle. In order to facilitate calculation, the included angle can also be Denoted as α; the angle between the excavator arm and the excavator arm is That is the second calibration angle. In order to facilitate calculation, the included angle can also be Denoted as β; the angle between the excavator arm and the excavator bucket is That is the third calibration angle. In order to facilitate calculation, the included angle can also be Denoted as γ.

[0047] Furthermore, the first calibration angle α, the second calibration angle β and the third calibration angle γ can be determined by the following method, and the following equations can be made based on the triangular relationship between the first calibration angle α, the second calibration angle β and the third calibration angle γ and the arm and the forearm of the excavator: Figure 2The auxiliary line shown by the dotted line can be obtained according to the trigonometric function relationship: the first calibration angle Since T1 is rigidly mounted on the boom, the angle Is a fixed value. The second calibration angle Since T2 is rigidly mounted on the forearm, the angle The third calibration angle Since the T3 is rigidly mounted on the bucket of the original excavator, the angle By combining the constant terms in the above formula, we can obtain the following conversion equation between joint angle information and tilt sensor readings, and thus determine the calibration angle information according to the following conversion equation:

[0048]

[0049] Among them, k, m, and n are the parameters of the angle conversion equation that need to be established; α, β, and γ are the first calibration angle, the second calibration angle, and the third calibration angle, respectively; θ1, θ2, θ3, and θ4 are the first measurement angle, the second measurement angle, the third measurement angle, and the fourth measurement angle, respectively.

[0050] In some optional embodiments, after the first calibration angle, the second calibration angle, and the third calibration angle are determined, the first calibration angle, the second calibration angle, the third calibration angle, and the end of the forearm can be used to determine the calibration angle. Figure 3 The displacement of point B in the figure determines the calibrated length of the boom and arm. The calibrated length is the length of the boom and arm determined by the calibration model. The displacement of point B can be determined by Figure 5 As shown, the displacement of point B can be determined by installing a laser rangefinder on a certain part of the excavator. Of course, the displacement of point B can also be determined by other instruments that can measure displacement, not necessarily a laser rangefinder, but also RTK (Real-time kinematic, real-time dynamic carrier phase difference technology); the distance measuring instrument can also be installed anywhere needed, not necessarily Figure 5 On the bucket shown. In some optional embodiments, the horizontal axis coordinate is x, and the vertical axis coordinate is z. According to the horizontal axis coordinate and the vertical axis coordinate, the first arm calibration length and the second arm calibration length are determined by the following formula. During the calculation process, the first calibration angle can be set as α, and the second calibration angle can be set as β. According to the trigonometric function relationship between the angle and other angles or sides, the robot arm calibration equation related to the end position as shown below is determined. The relationship between the horizontal axis coordinate x and other related sides is: The relationship between the vertical axis coordinate z and other related sides is: According to the horizontal coordinate x and the vertical coordinate z, and

[0051] The functional relationship between the first calibration angle and the second calibration angle is constructed as follows:

[0052]

[0053] Among them, a is the calibration length of the second arm, that is, the calibration length of the forearm, b is the calibration length of the first arm, that is, the calibration length of the upper arm, α is the first calibration angle, β is the second calibration angle; x is the horizontal axis coordinate, and z is the vertical axis coordinate. In some optional embodiments, after determining the calibration angle conversion equation and the manipulator calibration equation, the first measurement angle, the second measurement angle, the fourth measurement angle, the horizontal axis coordinate and the vertical axis coordinate under at least two postures are determined, and the following calculations are performed based on the first measurement angle, the second measurement angle, the fourth measurement angle, the horizontal axis coordinate, the vertical axis coordinate and the calibration angle conversion equation and the manipulator calibration equation to determine the first residual term and the second residual term. Then, according to the first residual term R x and the second residual term R z Determine the optimization objective function; further determine the first conversion parameter and the second conversion parameter based on the optimization objective function. The specific calculation is as follows:

[0054] α1=θ1-θ4-k,

[0055] α2=θ′1-θ′4-k,

[0056] β1=-θ1+θ2+m,

[0057] β2=-θ′1+θ′2+m,

[0058] Δx=b*cosα1-a*cos(β1+α1)-b*cosα2+a*cos(β2+α2),

[0059] Δz=b*sinα1-a*sin(β1+α1)-b*sinα2+a*sin(β2+α2),

[0060] R x =‖Δx′-Δx‖ 2

[0061] R z =‖Δz′-Δz‖ 2

[0062]

[0063] Wherein, a is the calibration length of the second arm, i.e., the calibration length of the forearm; b is the calibration length of the first arm, i.e., the calibration length of the upper arm; α1 is the first calibration angle in the first posture, i.e., the angle between the upper arm and the horizontal plane; β1 is the second calibration angle in the first posture, i.e., the angle between the forearm and the horizontal plane; α2 is the first calibration angle in the second posture, i.e., the angle between the upper arm and the horizontal plane; β2 is the second calibration angle in the second posture, i.e., the angle between the forearm and the horizontal plane; x1 is the x-axis displacement in the first posture; z1 is the z-axis displacement in the first posture; x2 is the x-axis displacement in the first posture; z2 is the z-axis displacement in the first posture; Δx′ is the horizontal axis displacement of the forearm between the first posture and the second posture; Δz′ is the vertical axis displacement of the forearm between the first posture and the second posture; R x is the residual term of the horizontal axis displacement of the forearm between the first posture and the second posture; R z is the residual term of the longitudinal displacement of the forearm between the first and second postures; i is the posture, R x is the residual term of the horizontal axis displacement of the forearm between the first and second postures, R z is the residual term of the longitudinal displacement of the forearm between the first and second postures.

[0064] In some optional embodiments, It is used to perform optimization calculations to reduce errors in the calculation process. Furthermore, after determining the residual terms under any two different postures, that is, the residual term under the first posture and the residual term under the second posture (of course, it can also be the residual terms under multiple postures, that is, multiple groups of residual terms, where multiple groups here refer to more than two groups), optimization is performed through the nonlinear optimization function shown below, so that the values ​​of the first arm calibration length, the second arm calibration length, the first conversion parameter, and the second conversion parameter of the determined target excavator are more accurate.

[0065] In some optional embodiments, through the calibration method of the present application, after the calibration angle conversion equation and the robotic arm calibration equation are determined, the joint angle and the arm and forearm lengths of any excavator to be calibrated (i.e., the target excavator in the present application) can be determined based on the first measurement angle, second measurement angle, third measurement angle, fourth measurement angle, and the calibration angle conversion equation and the robotic arm calibration equation read out.

[0066] In some optional embodiments, to verify the accuracy of the calibration method of the present application, the applicant also conducted verification tests using two types of excavators, A and B. The calibrated length of the boom of excavator A, determined by the calibration method of the present application, was 5.746m, while its actual size was 5.7m. The difference between the calibrated length and the actual size was 0.046m, or 4.6cm. The calibrated length of the arm of excavator A was 2.938m, while its actual size was 2.925m. The difference between the calibrated length and the actual size was 0.013m, or 1.3cm. The calibrated length of the boom of excavator B, determined by the calibration method of the present application, differed from its actual size by 0.02m, or 2cm. The calibrated length of the arm of excavator B differed from its actual size by 0.002m, or 0.2cm, and the joint angle difference was less than 1 degree.

[0067] From the above, it can be seen that the excavator arm motion calibration solution provided by this application first (such as Figure 2 As shown in the figure, the excavator cabin, the connection points of the excavator's boom and arm, and the connection points of the arm and bucket are determined. According to the above connection points, a straight rod model of the excavator is constructed, that is, the boom and arm of the excavator are regarded as straight lines, that is, the boom and arm are as follows: Figure 2 As shown in the figure, OA and AB are measured by inclination sensors arranged on different joints under the straight rod model to determine the joint angle information of each part of the excavator, and the calibration angle conversion equation of the angle to be calibrated (the angle between the parts of the excavator) is determined according to the triangular relationship between the joint angle information and the excavator's main arm and forearm; further, the displacement information of the first arm and the second arm is obtained, and further, the mechanical arm calibration equation is determined according to the displacement information of the first arm and the second arm and the calibration angle conversion equation; and then, a universal calibration model is determined according to the calibration angle conversion equation and the mechanical arm calibration equation. After the universal calibration model is determined, when calibrating any excavator through the universal calibration model, the excavator can be calibrated by only obtaining the joint angle information of the excavator (i.e., the measurement angle of the inclination sensor), the displacement information of the first arm and the displacement information of the second arm, thereby determining the conversion parameters of the excavator and the length of the excavator's large and small arms. This application determines the calibration model by straightening the excavator's mechanical arm, so that the calibration model is applicable to different models of excavators. When using the calibration model to calibrate the relevant parameters of the excavator, there is no need to obtain the precise three-dimensional structure of the excavator arm, and the accuracy of the calibration results can also be guaranteed. Therefore, this application effectively solves the problem in the existing technology that the calibration model relies on the three-dimensional model and has low practicality.

[0068] It should be noted that the method of the embodiment of the present application can be performed by a single device, such as a computer or server. The method of this embodiment can also be applied in a distributed scenario and performed by multiple devices working together. In such a distributed scenario, one of the multiple devices may only perform one or more steps of the method of the embodiment of the present application, and the multiple devices will interact with each other to complete the method.

[0069] It should be noted that the above description is limited to some embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in an order different from that described in the above embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0070] Based on the same inventive concept, corresponding to any of the above-mentioned embodiment methods, the present application also provides an excavator mechanical arm motion calibration device.

[0071] refer to Figure 4 , the excavator mechanical arm motion calibration device comprises:

[0072] An acquisition module 402 is configured to acquire corresponding joint angle information and first arm displacement information of the initial excavator in at least three different postures;

[0073] A first determination module 404 is configured to determine a calibration angle conversion equation according to the joint angle information;

[0074] A second determination module 406 is configured to determine a robotic arm calibration equation based on the first arm displacement information and the calibration angle conversion equation;

[0075] The calibration module 408 is configured to determine the corresponding joint angle information and first arm displacement information of the target excavator in at least three different postures, and calibrate the target excavator through the manipulator calibration model based on the joint angle information and first arm displacement information of the target excavator; wherein the manipulator calibration model performs calibration calculation according to a preset optimization function.

[0076] In some optional implementations, the joint angle information in the acquisition module 402 includes: a first measurement angle, a second measurement angle, a third measurement angle, and a fourth measurement angle;

[0077] The obtaining of corresponding joint angle information of the initial excavator in at least three different postures includes:

[0078] The joint angle information is obtained according to the inclination sensors provided at the joints of the initial excavator; wherein the joint angle information is the angle between the joint where the inclination sensor is provided and the horizontal plane.

[0079] In some optional embodiments, the acquisition module 402 includes: a first arm, a second arm, a bucket, and a cabin;

[0080] The method comprises:

[0081] The first measurement angle is determined by the inclination sensor provided on the first arm of the excavator;

[0082] The second measurement angle is determined by the inclination sensor provided on the second arm of the excavator;

[0083] The third measurement angle is determined by the inclination sensor provided on the bucket of the excavator;

[0084] The fourth measurement angle is determined by the inclination sensor provided on the cabin of the excavator.

[0085] In some optional embodiments, in the acquisition module 402 , the first arm is a forearm of the excavator, and the second arm is a boom of the excavator.

[0086] In some optional implementations, in the acquisition module 402 , the first arm displacement information includes: displacement information of the end of the forearm of the initial excavator.

[0087] In some optional implementations, the calibration angle conversion equation of the first determining module 404 includes: a first calibration angle equation, a second calibration angle equation, and a third calibration angle equation;

[0088] Determining a calibration angle conversion equation according to the joint angle information includes:

[0089] Determine a first conversion parameter, and determine the first calibration angle equation according to the first measurement angle, the fourth measurement angle, and the first conversion parameter;

[0090] Determine a second conversion parameter, and determine the second calibration angle equation according to the first measurement angle, the second measurement angle, and the second conversion parameter;

[0091] Determining a third conversion parameter, and determining the third calibration angle equation according to the second measurement angle, the third measurement angle, and the third conversion parameter;

[0092] The calibration angle conversion equation is determined according to the first calibration angle equation, the second calibration angle equation and the third calibration angle equation; wherein the first calibration angle, the second calibration angle and the third calibration angle are determined according to the first calibration angle equation, the second calibration angle equation and the third calibration angle equation.

[0093] In some optional implementations, the first determining module 404 determines the robotic arm calibration equation based on the first arm displacement information and the calibration angle conversion equation, including:

[0094] determining a position conversion equation according to the first arm displacement information, the first calibration angle, and the second calibration angle;

[0095] The robotic arm calibration equation is determined according to the position conversion equation and the calibration angle conversion equation.

[0096] In some optional embodiments, the second determining module 406 includes determining the mechanical arm calibration equation shown below based on the first arm displacement information of the initial excavator at any posture and the calibration angle conversion equation;

[0097] α1=θ1-θ4-k,

[0098] α2=θ′1-θ′4-k,

[0099] β1=-θ1+θ2+m,

[0100] β2=-θ′1+θ′2+m,

[0101] Δx=b*cosα1-a*cos(β1+α1)-b*cosα2+a*cos(β2+α2),

[0102] Δz=b*sinα1-a*sin(β1+α1)-b*sinα2+a*sin(β2+α2),

[0103] R x =‖Δx′-Δx‖ 2

[0104] R z =‖Δz′-Δz‖ 2

[0105]

[0106] Wherein, a is the calibration length of the second arm, i.e., the calibration length of the forearm; b is the calibration length of the first arm, i.e., the calibration length of the upper arm; α1 is the first calibration angle in the first posture, i.e., the angle between the upper arm and the horizontal plane; β1 is the second calibration angle in the first posture, i.e., the angle between the forearm and the horizontal plane; α2 is the first calibration angle in the second posture, i.e., the angle between the upper arm and the horizontal plane; β2 is the second calibration angle in the second posture, i.e., the angle between the forearm and the horizontal plane; x1 is the x-axis displacement in the first posture; z1 is the z-axis displacement in the first posture; x2 is the x-axis displacement in the first posture; z2 is the z-axis displacement in the first posture; Δx′ is the horizontal axis displacement of the forearm between the first posture and the second posture; Δz′ is the vertical axis displacement of the forearm between the first posture and the second posture; R x is the residual term of the horizontal axis displacement of the forearm between the first posture and the second posture; R z is the residual term of the longitudinal displacement of the forearm between the first and second postures; i is the posture, R x is the residual term of the horizontal axis displacement of the forearm between the first and second postures, R z is the residual term of the longitudinal displacement of the forearm between the first and second postures.

[0107] In some optional implementations, the calibration module 408 includes:

[0108] Determining the calibration angle of the target excavator according to the joint angle information and the first arm displacement information of the target excavator through the calibration angle conversion equation;

[0109] According to the calibration angle and first arm displacement information of the target excavator, the first arm calibration length and the second arm calibration length, the first conversion parameter and the second conversion parameter of the target excavator are determined through the mechanical arm calibration equation.

[0110] In some optional implementations, the calibration module 408 further includes a third conversion parameter;

[0111] The third conversion parameter is determined by the following method, including:

[0112] Obtaining a bucket joint angle corresponding to the bucket of the target excavator reaching a specified posture;

[0113] The third conversion parameter is determined according to the bucket joint angle.

[0114] For the convenience of description, the above devices are described as being divided into various modules according to their functions. Of course, when implementing this application, the functions of each module can be implemented in the same or multiple software and / or hardware.

[0115] The device of the above embodiment is used to implement the corresponding excavator mechanical arm motion calibration method in any of the above embodiments, and has the beneficial effects of the corresponding method embodiment, which will not be repeated here.

[0116] Based on the same inventive concept, corresponding to any of the above-mentioned embodiments and methods, the present application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and runnable on the processor, wherein when the processor executes the program, the excavator mechanical arm motion calibration method described in any of the above embodiments is implemented.

[0117] Figure 6 10 is a schematic diagram showing a more specific hardware structure of an electronic device provided in this embodiment. The device may include: a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, the memory 1020, the input / output interface 1030, and the communication interface 1040 are communicatively connected to each other within the device via the bus 1050.

[0118] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0119] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage devices, dynamic storage devices, etc. The memory 1020 can store an operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0120] The input / output interface 1030 is used to connect input / output modules to implement information input and output. The input / output modules can be configured as components within the device (not shown in the figure) or can be externally connected to the device to provide corresponding functions. Input devices may include a keyboard, mouse, touch screen, microphone, various sensors, etc., and output devices may include a display, speaker, vibrator, indicator light, etc.

[0121] The communication interface 1040 is used to connect to a communication module (not shown) to enable communication between the device and other devices. The communication module can communicate via a wired method (such as USB, network cable, etc.) or a wireless method (such as mobile network, WiFi, Bluetooth, etc.).

[0122] The bus 1050 comprises a path for transmitting information between the various components of the device (eg, the processor 1010 , the memory 1020 , the input / output interface 1030 , and the communication interface 1040 ).

[0123] It should be noted that although the above device only shows the processor 1010, the memory 1020, the input / output interface 1030, the communication interface 1040, and the bus 1050, in a specific implementation, the device may also include other components necessary for normal operation. In addition, it will be understood by those skilled in the art that the above device may only include the components necessary to implement the embodiments of this specification, and does not necessarily include all the components shown in the figure.

[0124] The electronic device of the above embodiment is used to implement the corresponding excavator mechanical arm motion calibration method in any of the above embodiments, and has the beneficial effects of the corresponding method embodiment, which will not be repeated here.

[0125] Based on the same inventive concept, corresponding to any of the above-mentioned embodiment methods, the present application also provides a non-transitory computer-readable storage medium, wherein the non-transitory computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the excavator mechanical arm motion calibration method as described in any of the above embodiments.

[0126] The computer-readable media of this embodiment include permanent and non-permanent, removable and non-removable media that can be used to store information by any method or technology. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, read-only compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device.

[0127] The computer instructions stored in the storage medium of the above embodiment are used to enable the computer to execute the excavator mechanical arm motion calibration method as described in any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0128] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present application (including the claims) is limited to these examples. Within the scope of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0129] In addition, for simplicity of description and discussion, and in order not to make the embodiment of the application difficult to understand, the known power supply / ground connection with integrated circuit (IC) chip and other components may or may not be shown in the accompanying drawings provided. In addition, the device can be shown in the form of a block diagram to avoid making the embodiment of the application difficult to understand, and this also takes into account the following fact, that is, the details of the embodiment of these block diagram devices are highly dependent on the platform to be implemented in the embodiment of the application (that is, these details should be fully within the scope of understanding of those skilled in the art). When specific details (for example, circuit) are set forth to describe exemplary embodiments of the application, it will be apparent to those skilled in the art that the embodiment of the application can be implemented without these specific details or when these specific details are changed. Therefore, these descriptions should be considered to be illustrative rather than restrictive.

[0130] Although the present invention has been described in conjunction with specific embodiments thereof, many alternatives, modifications, and variations of these embodiments will be apparent to those skilled in the art based on the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may utilize the embodiments discussed.

[0131] The embodiments of the present application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of this application.

Claims

1. A method for calibrating the motion of an excavator manipulator arm, characterized in that: include: Obtaining corresponding joint angle information and first arm displacement information of the initial excavator in at least three different postures; The joint angle information includes: a first measurement angle, a second measurement angle, a third measurement angle, and a fourth measurement angle; The obtaining of corresponding joint angle information of the initial excavator in at least three different postures includes: The joint angle information is obtained according to the inclination sensors provided at the joints of the initial excavator; wherein the joint angle information is the angle between the joints provided with the inclination sensors and the horizontal plane; the excavator includes: a first arm, a second arm, a bucket, and a cabin; The first measurement angle is determined by the inclination sensor provided on the first arm of the excavator; The second measurement angle is determined by the inclination sensor provided on the second arm of the excavator; The third measurement angle is determined by the inclination sensor provided on the bucket of the excavator; The fourth measurement angle is determined by the inclination sensor provided in the cabin of the excavator; Determining a calibration angle conversion equation according to the joint angle information; Determining a robotic arm calibration equation based on the first arm displacement information and the calibration angle conversion equation; Determine the corresponding joint angle information and first arm displacement information of the target excavator in at least three different postures, and calibrate the target excavator through the manipulator calibration equation based on the joint angle information and first arm displacement information of the target excavator; wherein the calibration angle conversion equation and the manipulator calibration equation are calibrated and calculated according to a preset optimization function.

2. The method according to claim 1, characterized in that The first arm is the forearm of the excavator, and the second arm is the boom of the excavator.

3. The method according to claim 2, characterized in that The first arm displacement information includes: displacement information of the end of the forearm of the initial excavator.

4. The method according to claim 2, characterized in that The calibration angle conversion equation includes: a first calibration angle equation, a second calibration angle equation, and a third calibration angle equation; Determining a calibration angle conversion equation according to the joint angle information includes: Determine a first conversion parameter, and determine the first calibration angle equation according to the first measurement angle, the fourth measurement angle, and the first conversion parameter; Determine a second conversion parameter, and determine the second calibration angle equation according to the first measurement angle, the second measurement angle, and the second conversion parameter; Determining a third conversion parameter, and determining the third calibration angle equation according to the second measurement angle, the third measurement angle, and the third conversion parameter; The calibration angle conversion equation is determined according to the first calibration angle equation, the second calibration angle equation and the third calibration angle equation; wherein the first calibration angle, the second calibration angle and the third calibration angle are determined according to the first calibration angle equation, the second calibration angle equation and the third calibration angle equation.

5. The method according to claim 4, characterized in that Determining a robotic arm calibration equation based on the first arm displacement information and the calibration angle conversion equation includes: determining a position conversion equation according to the first arm displacement information, the first calibration angle, and the second calibration angle; The robotic arm calibration equation is determined according to the position conversion equation and the calibration angle conversion equation.

6. The method according to claim 5, characterized in that Determining the robotic arm calibration equation according to the first arm displacement information and the calibration angle conversion equation includes: Determine the mechanical arm calibration equation shown below based on the first arm displacement information of the initial excavator in any posture and the calibration angle conversion equation; Wherein, a is the second arm calibration length, that is, the forearm calibration length, b is the first arm calibration length, that is, the upper arm calibration length, α1 is the first calibration angle in the first posture, that is, the angle between the upper arm and the horizontal plane, β1 is the second calibration angle in the first posture, that is, the angle between the forearm and the horizontal plane, α2 is the first calibration angle in the second posture, that is, the angle between the upper arm and the horizontal plane, β2 is the second calibration angle in the second posture, that is, the angle between the forearm and the horizontal plane, x1 is the x-axis displacement in the first posture, z1 is the z-axis displacement in the first posture, x2 is the x-axis displacement in the first posture, and z2 is the z-axis displacement in the first posture; is the horizontal axis displacement of the forearm between the first and second postures; is the longitudinal displacement of the forearm between the first and second postures; is the residual term of the horizontal axis displacement of the forearm between the first posture and the second posture; is the residual term of the longitudinal displacement of the forearm between the first and second postures; i is the posture, is the residual term of the horizontal axis displacement of the forearm between the first posture and the second posture, is the residual term of the longitudinal displacement of the forearm between the first and second postures.

7. The method according to claim 1, characterized in that The determining of corresponding joint angle information and first arm displacement information of the target excavator in at least three different postures, and calibrating the target excavator using the manipulator calibration equation according to the joint angle information and the first arm displacement information of the target excavator, includes: Determining the calibration angle of the target excavator according to the joint angle information and the first arm displacement information of the target excavator through the calibration angle conversion equation; According to the calibration angle and first arm displacement information of the target excavator, the first arm calibration length, the second arm calibration length, the first conversion parameter and the second conversion parameter of the target excavator are determined through the mechanical arm calibration equation.

8. The method according to claim 7, characterized in that Also included is a third conversion parameter; The third conversion parameter is determined by the following method, including: Obtaining a bucket joint angle corresponding to the bucket of the target excavator reaching a specified posture; The third conversion parameter is determined according to the bucket joint angle.

9. A motion calibration device for an excavator mechanical arm, characterized in that: include: an acquisition module configured to acquire corresponding joint angle information and first arm displacement information of the initial excavator in at least three different postures; a first determining module, configured to determine a calibration angle conversion equation according to the joint angle information; The joint angle information includes: a first measurement angle, a second measurement angle, a third measurement angle, and a fourth measurement angle; The obtaining of corresponding joint angle information of the initial excavator in at least three different postures includes: The joint angle information is obtained according to the inclination sensors provided at the joints of the initial excavator; wherein the joint angle information is the angle between the joints provided with the inclination sensors and the horizontal plane; the excavator includes: a first arm, a second arm, a bucket, and a cabin; The first measurement angle is determined by the inclination sensor provided on the first arm of the excavator; The second measurement angle is determined by the inclination sensor provided on the second arm of the excavator; The third measurement angle is determined by the inclination sensor provided on the bucket of the excavator; The fourth measurement angle is determined by the inclination sensor provided in the cabin of the excavator; a second determining module, configured to determine a robotic arm calibration equation based on the first arm displacement information and the calibration angle conversion equation; The calibration module is configured to determine the corresponding joint angle information and first arm displacement information of the target excavator in at least three different postures, and calibrate the target excavator through the manipulator calibration equation based on the joint angle information and first arm displacement information of the target excavator; wherein the calibration angle conversion equation and the manipulator calibration equation are calibrated and calculated according to a preset optimization function.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable by the processor, wherein the processor implements the method according to any one of claims 1 to 8 when executing the computer program. 11 . A non-transitory computer-readable storage medium storing computer instructions for causing a computer to execute the method according to claim 1 .

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