A control method and control system for attachment translation and lifting

Abstract

An embodiment of the present invention provides a control method and a control system for the translation and lifting of an attachment. The control method for the translation and lifting of the attachment includes: obtaining a first target rotation angle of a rocker arm corresponding to the rotation angle of a boom according to the data of a low calibration point sensor, and obtaining a second target rotation angle of the rocker arm corresponding to the rotation angle of the boom according to the data of a high calibration point sensor; correcting the first target rotation angle according to the data of the high calibration point sensor to obtain a first corrected target rotation angle, and correcting the second target rotation angle according to the data of the low calibration point sensor to obtain a second corrected target rotation angle; obtaining a translation and lifting target rotation angle of the rocker arm according to the rotation angle of the boom, the first corrected target rotation angle, and the second corrected target rotation angle. An embodiment of the present invention provides a control method and a control system for the translation and lifting of an attachment to achieve the purpose of the translation and lifting of a loader attachment and reduce calculation and control deviations.

Description

Technical Field

[0001] The present invention relates to mechanical control technology, and in particular, to a control method and control system for attachment translation and lifting. Background Art

[0002] A wheel loader is an important construction machinery equipment, which is widely used in infrastructure construction, mining, wood handling and other fields, and has good working condition adaptability. However, for the continuously emerging new application working conditions, it is still necessary to continuously improve the adaptability of the wheel loader to different working conditions.

[0003] Under certain operating conditions, the boom needs to be lifted while the attachment remains translated, that is, as the boom is lifted or lowered, the angle of the attachment relative to the ground remains unchanged. One way to achieve attachment translation during lifting is to achieve it through a special design of the working device mechanism. This way is complex in design and will also reduce the adaptability of the wheel loader to other operating conditions.

[0004] Another way is to adjust the extension or shortening of the bucket cylinder during the boom lifting process to achieve nearly translational movement of the attachment, that is, electric control translation and lifting. This way can achieve the translational lifting of the attachment and does not affect the adaptability of the whole machine to other working conditions, but has high requirements for calculation methods, calculation accuracy and control algorithms. In the existing methods, the rotation angles of the boom and the rocker arm are detected by sensors, and then the target change angle of the rocker arm is calculated based on the angle change of the boom. The controller controls the rocker arm to approach the target angle in real time to dynamically achieve the translational lifting of the attachment. In this implementation method, the sensor data needs to be calibrated, and the calibration method of the sensor data, the calculation method of the target angle of the rocker arm, and the control algorithm of the rocker arm will all affect the control accuracy and control effect of the entire system. Summary of the Invention

[0005] Embodiments of the present invention provide a control method and control system for attachment translation and lifting to achieve the purpose of translational lifting of the wheel loader attachment and reduce calculation and control deviations.

[0006] In a first aspect, embodiments of the present invention provide a control method for attachment translation and lifting, including:

[0007] Obtaining a first target rotation angle of the rocker arm corresponding to the rotation angle of the boom according to the low calibration point sensor data, and obtaining a second target rotation angle of the rocker arm corresponding to the rotation angle of the boom according to the high calibration point sensor data;

[0008] Correcting the first target rotation angle according to the high calibration point sensor data to obtain a first corrected target rotation angle, and correcting the second target rotation angle according to the low calibration point sensor data to obtain a second corrected target rotation angle;

[0009] Obtain the translation and lifting target rotation angle of the rocker arm according to the rotation angle of the boom, the first corrected target rotation angle, and the second corrected target rotation angle.

[0010] Optionally, obtaining the translation and lifting target rotation angle of the rocker arm according to the rotation angle of the boom, the first corrected target rotation angle, and the second corrected target rotation angle includes:

[0011] According to the rotation angle of the boom, weight and add the first corrected target rotation angle and the second corrected target rotation angle as the translation and lifting target rotation angle.

[0012] Optionally, after obtaining the translation and lifting target rotation angle of the rocker arm according to the rotation angle of the boom, the first corrected target rotation angle, and the second corrected target rotation angle, it further includes:

[0013] According to the relationship between the translation and lifting target rotation angle of the rocker arm and the rotation angle of the boom, obtain the corresponding relationship between the change in the rotation angle of the rocker arm and the change in the rotation angle of the boom;

[0014] According to the corresponding relationship between the change in the rotation angle of the rocker arm and the change in the rotation angle of the boom, obtain the corresponding relationship between the action current of the rocker arm cylinder and the action current of the boom cylinder.

[0015] Optionally, after obtaining the corresponding relationship between the action current of the rocker arm cylinder and the action current of the boom cylinder according to the corresponding relationship between the change in the rotation angle of the rocker arm and the change in the rotation angle of the boom, it further includes:

[0016] During the translation and lifting process, obtain the action current of the boom cylinder in real time; according to the corresponding relationship between the current action current of the boom cylinder and the calculated value of the action current of the rocker arm cylinder, obtain the action current of the rocker arm cylinder.

[0017] Optionally, after obtaining the action current of the rocker arm cylinder according to the corresponding relationship between the current action current of the boom cylinder and the calculated value of the action current of the rocker arm cylinder, it further includes:

[0018] Control the action current of the rocker arm cylinder so that the difference between the rotation angle of the rocker arm and the translation and lifting target rotation angle is less than a preset value.

[0019] Optionally, correcting the first target rotation angle according to the high-position calibration point sensor data to obtain the first corrected target rotation angle includes:

[0020] According to the low-position calibration point, obtain the first target angle of the rocker arm corresponding to the angle of the attachment at the extreme lifting limit of the boom being 0°;

[0021] Based on the rocker arm angle sensor data calibrated at the high calibration point, the theoretical angle of the attachment at the high calibration point, and the resolution of the rocker arm angle sensor, obtain the target angle two of the rocker arm corresponding to the attachment angle of 0° at the high calibration point, and obtain the difference between the target angle two and the target angle one;

[0022] Based on the rotation angle of the boom, the difference between the target angle two and the target angle one, and the first target rotation angle, obtain the first corrected target rotation angle.

[0023] Optionally, correcting the second target rotation angle according to the low calibration point sensor data to obtain a second corrected target rotation angle includes:

[0024] Based on the high calibration point, obtain the target angle three of the rocker arm corresponding to the attachment angle of 0° when the attachment is flat on the ground;

[0025] Based on the rocker arm angle sensor data calibrated at the low calibration point, the theoretical angle of the attachment at the low calibration point, and the resolution of the rocker arm angle sensor, obtain the target angle four of the rocker arm corresponding to the attachment angle of 0° at the low calibration point, and obtain the difference between the target angle four and the target angle three;

[0026] Based on the rotation angle of the boom, the difference between the target angle four and the target angle three, and the second target rotation angle, obtain the second corrected target rotation angle.

[0027] Optionally, when obtaining the first target rotation angle of the rocker arm corresponding to the rotation angle of the boom according to the low calibration point sensor data and the second target rotation angle of the rocker arm corresponding to the rotation angle of the boom according to the high calibration point sensor data, it further includes:

[0028] Select several boom angle points at equal angles within the rotation angle range of the boom to calculate the target angle of the rocker arm, and calculate the target angle of the rocker arm between two boom angle points by linear interpolation.

[0029] Optionally, obtaining the operating current of the rocker arm cylinder according to the corresponding relationship between the current operating current of the boom cylinder and the calculated value of the operating current of the rocker arm cylinder includes:

[0030] If the current operating current of the rocker arm cylinder is greater than the calculated value of the operating current of the rocker arm cylinder corresponding to the boom angle point, the operating current of the rocker arm cylinder maintains the current current;

[0031] If the current operating current of the rocker arm cylinder is less than the calculated value of the operating current of the rocker arm cylinder corresponding to the boom angle point, the operating current of the rocker arm cylinder is equal to the calculated value of the operating current of the rocker arm cylinder.

[0032] Second aspect, an embodiment of the present invention provides a control system for the translation and lifting of an attachment, including a rocker arm angle sensor, a boom angle sensor, and a controller. The rocker arm angle sensor is configured to detect the rotation angle of the rocker arm, the boom angle sensor is configured to detect the rotation angle of the boom, and both the rocker arm angle sensor and the boom angle sensor are electrically connected to the controller. The controller includes:

[0033] One or more processors;

[0034] A memory for storing one or more programs;

[0035] When the one or more programs are executed by the one or more processors, the one or more processors implement the control method as described in the first aspect.

[0036] Compared with the prior art where only a single reference point is used to obtain the target rotation angle of the rocker arm, a control method for the translation and lifting of an attachment provided by an embodiment of the present invention calculates the target rotation angle of the rocker arm at different boom heights based on multiple reference points, corrects the target rotation angle of the rocker arm according to the calibration data of the angle sensor, and then obtains the target rotation angle for the translation and lifting of the rocker arm based on the first corrected target rotation angle, the second corrected target rotation angle, and the rotation angle of the boom obtained after correction. The purpose of the translation and lifting of the loader attachment is achieved, and the calculation and control deviation are reduced. It is simple and convenient to implement, which is beneficial to improving the operation efficiency and ensuring the control effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of the low-point calibration position of the loader;

[0038] Figure 2 Schematic diagram of the high-point calibration position of the loader;

[0039] Figure 3 Flowchart of a control method for the translation and lifting of an attachment provided by an embodiment of the present invention;

[0040] Figure 4 Flowchart of another control method for the translation and lifting of an attachment provided by an embodiment of the present invention;

[0041] Figure 5 For Figure 3 Flowchart of the detailed steps for obtaining the first corrected target rotation angle in step S102 in

[0042] Figure 6 For Figure 3 Flowchart of the detailed steps for obtaining the second corrected target rotation angle in step S102 in

[0043] Figure 7 Schematic diagram of a relationship between the bucket angle and the rocker arm angle;

[0044] Figure 8 It is another schematic diagram of the relationship between the bucket angle and the rocker arm angle;

[0045] Figure 9 It is a schematic diagram of the geometric relationship for calculating the follow-up angle of the rocker arm;

[0046] Figure 10 It is a schematic diagram of a geometric relationship for calculating the change in the lengths of the boom cylinder and the rocker arm cylinder;

[0047] Figure 11 It is another schematic diagram of the geometric relationship for calculating the change in the lengths of the boom cylinder and the rocker arm cylinder;

[0048] Figure 12 It is a schematic diagram of the current adjustment of the rocker arm cylinder;

[0049] Figure 13 It is a schematic diagram of the structure of a controller provided by an embodiment of the present invention. Detailed implementation manners

[0050] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the sake of description, only parts related to the present invention are shown in the drawings, rather than all the structures.

[0051] Optionally, before introducing the embodiments of the present invention, the deployment of the control system for the attachment translation and lifting will be introduced first. The control system for the attachment translation and lifting can be deployed in a loader.

[0052] Figure 1 It is a schematic diagram of the low-point positioning of the loader, Figure 2 It is a schematic diagram of the high-point positioning of the loader, referring to Figure 1 and Figure 2 , the loader includes a rocker arm angle sensor, a boom angle sensor, a boom operation handle, a controller, a bucket closing solenoid valve, a bucket opening solenoid valve, a lifting solenoid valve, and a lowering solenoid valve. The working device of the loader includes a boom 2 with its rear end A connected to the front frame 1, and a boom cylinder ( Figure 1 not shown in

[0053] The rocker arm angle sensor is installed at the connection between the rocker arm 5 and the boom 2, and is used to detect the angle of the rocker arm relative to the boom. The boom angular displacement sensor is installed at the connection between the boom 2 and the front frame 1, and is used to detect the angle change of the boom 2 relative to the front frame 1.

[0054] The boom operation handle is electrically connected to the controller, and the controller detects the electrical signal of the boom operation handle to control the actions of the boom 2 and the attachment 5. When the boom operation handle is pulled backward, the controller controls the lifting solenoid valve to actuate to lift the boom 2. When the boom operation handle is pushed forward, the controller controls the lowering solenoid valve to actuate to lower the boom 2.

[0055] When the controller controls the bucket closing solenoid valve to actuate, the attachment 4 rotates along the bucket closing direction, and when the controller controls the bucket opening solenoid valve to actuate, the attachment 4 rotates along the bucket opening direction. During the lifting and lowering process of the boom 2, the controller automatically controls the bucket closing solenoid valve and the bucket opening solenoid valve to actuate to maintain the relative angle between the attachment 4 and the ground unchanged, and realize the translational lifting of the attachment 4.

[0056] Figure 3 It is a flowchart of a control method for attachment translational lifting provided by an embodiment of the present invention. Refer to Figures 1 - 3 , the control method for attachment translational lifting includes:

[0057] S101. Obtain the first target rotation angle of the rocker arm corresponding to the boom rotation angle according to the low calibration point sensor data, and obtain the second target rotation angle of the rocker arm corresponding to the boom rotation angle according to the high calibration point sensor data.

[0058] Refer to Figure 1 , the low calibration point is the position where the attachment 4 is laid flat on the ground. Refer to Figure 2 , the high calibration point is the boom lifting limit and the bucket closing limit position.

[0059] In this step, the values of the rocker arm angle sensor and the boom angle sensor at the low calibration point and the high calibration point are respectively calibrated, and the first target rotation angle and the second target rotation angle of the rocker arm are formed and stored. It should be noted that both the first target rotation angle and the second target rotation angle are the target rotation angles of the rocker arm. The first target rotation angle represents the target rotation angle of the rocker arm calibrated according to the low calibration point sensor data, and the second target rotation angle represents the target rotation angle of the rocker arm calibrated according to the high calibration point sensor data.

[0060] The low calibration point sensor data includes the calibration data of the angle sensor at the low calibration point position, and the high calibration point sensor data includes the calibration data of the angle sensor at the high calibration point position. The calibration data of the angle sensor includes the calibration data of the rocker arm angle sensor and the calibration data of the boom angle sensor.

[0061] S102. Correct the first target rotation angle based on the high-position calibration point sensor data to obtain the first corrected target rotation angle, and correct the second target rotation angle based on the low-position calibration point sensor data to obtain the second corrected target rotation angle.

[0062] In this step, obtain the first corrected target rotation angle after correcting the first target rotation angle, and the second corrected target rotation angle after correcting the second target rotation angle.

[0063] S103. Based on the rotation angle of the boom, the first corrected target rotation angle, and the second corrected target rotation angle, obtain the translational lifting target rotation angle of the rocker arm.

[0064] In this step, the translational lifting target rotation angle of the rocker arm is the target rotation angle of the rocker arm, and the translational lifting target rotation angle represents the finally formed target rotation angle of the rocker arm.

[0065] Compared with the prior art in which the target rotation angle of the rocker arm is obtained only based on a single reference point. A control method for the translational lifting of an attachment provided by an embodiment of the present invention calculates the target rotation angle of the rocker arm at different boom heights based on multiple reference points, corrects the target rotation angle of the rocker arm according to the calibration data of the angle sensor, and then obtains the translational lifting target rotation angle of the rocker arm based on the first corrected target rotation angle, the second corrected target rotation angle, and the rotation angle of the boom obtained after correction. The purpose of the translational lifting of the loader attachment is achieved, and the calculation and control deviation are reduced. The implementation is simple and convenient, which is beneficial to improving the operation efficiency and ensuring the control effect.

[0066] Figure 4 This is a flowchart of another control method for the translational lifting of an attachment provided by an embodiment of the present invention. Refer to Figure 4 , the control method for the translational lifting of the attachment includes:

[0067] S201. Obtain the first target rotation angle of the rocker arm corresponding to the rotation angle of the boom according to the low-position calibration point sensor data, and obtain the second target rotation angle of the rocker arm corresponding to the rotation angle of the boom according to the high-position calibration point sensor data.

[0068] S202. Correct the first target rotation angle based on the high-position calibration point sensor data to obtain the first corrected target rotation angle, and correct the second target rotation angle based on the low-position calibration point sensor data to obtain the second corrected target rotation angle.

[0069] S203. Weighted sum the first corrected target rotation angle and the second corrected target rotation angle according to the rotation angle of the boom as the translational lifting target rotation angle.

[0070] S204. Obtain the corresponding relationship between the change in the rotation angle of the rocker arm and the change in the rotation angle of the boom according to the relationship between the translation and lifting target rotation angle of the rocker arm and the rotation angle of the boom.

[0071] S205. Obtain the corresponding relationship between the operating current of the rocker arm cylinder and the operating current of the boom cylinder according to the corresponding relationship between the change in the rotation angle of the rocker arm and the change in the rotation angle of the boom.

[0072] S206. During the translation and lifting process, obtain the operating current of the boom cylinder in real time; obtain the operating current of the rocker arm cylinder according to the corresponding relationship between the current operating current of the boom cylinder and the calculated value of the operating current of the rocker arm cylinder.

[0073] S207. Control the operating current of the rocker arm cylinder so that the difference between the rotation angle of the rocker arm and the translation and lifting target rotation angle is less than a preset value.

[0074] In this step, the controller controls the operating current of the rocker arm cylinder so that the rotation angle of the rocker arm approaches or is equal to the target angle of the rocker arm. That is, the preset value is a small value close to 0. That is to say, when driving the rocker arm to move according to the operating current of the rocker arm cylinder, real-time fine adjustment is performed on the basis of the operating current of the rocker arm cylinder to reduce the control deviation.

[0075] In the embodiment of the present invention, the target rotation angle of the rocker arm at different boom heights is calculated based on multiple reference points, and the target rotation angle of the rocker arm is corrected according to the calibration data of the angle sensor. The corresponding change in the rocker arm angle is calculated based on the target rotation angle of the rocker arm corresponding to different boom rotation angles, and the relationship between the rocker arm operating current and the boom operating current is determined based on the relationship between the change in the rocker arm angle and the boom rotation angle. During the lifting and lowering of the boom, the rocker arm is controlled based on the calculated value of the rocker arm operating current and the target rotation angle of the rocker arm, achieving the purpose of translational lifting of the loader attachment, reducing calculation and control deviations. It is simple and convenient to implement, beneficial to improving the operation efficiency, and ensuring the control effect.

[0076] Optionally, when performing the above step S101, the control method for attachment translation and lifting further includes: selecting a number of boom angle points at equal angles within the rotation angle range of the boom to calculate the target angle of the rocker arm, and calculating the target angle of the rocker arm between two boom angle points by linear interpolation.

[0077] Figure 5 For Figure 3 the detailed flowchart of the refinement steps for obtaining the first corrected target rotation angle in step S102, refer to Figure 3 and Figure 5 , the steps of correcting the first target rotation angle according to the data of the high-position calibration point sensor to obtain the first corrected target rotation angle in step S102 include:

[0078] S301. Obtain the first target angle of the rocker arm corresponding to the angle of the attachment being 0° at the lower calibration point.

[0079] S302. According to the rocker arm angle sensor data calibrated at the upper calibration point, the theoretical angle of the attachment at the upper calibration point, and the resolution of the rocker arm angle sensor, obtain the second target angle of the rocker arm corresponding to the angle of the attachment being 0° at the upper calibration point, and obtain the difference between the second target angle and the first target angle.

[0080] S303. According to the rotation angle of the boom, the difference between the second target angle and the first target angle, and the first target rotation angle, obtain the first corrected target rotation angle.

[0081] In this step, after taking a certain coefficient for the difference between the second target angle and the first target angle according to the rotation angle of the boom, add it to the calculated value of the target angle of the rocker arm. It should be noted that both the first target angle and the second target angle are the target rotation angles of the rocker arm, and for clarity, they are respectively used to represent the target rotation angles of the rocker arm corresponding to each different step.

[0082] Figure 6 For Figure 3 the detailed flowchart of the steps to obtain the second corrected target rotation angle in step S102, refer to Figure 3 and Figure 6 , the steps in step S102 to correct the second target rotation angle according to the lower calibration point sensor data to obtain the second corrected target rotation angle include:

[0083] S401. Obtain the third target angle of the rocker arm corresponding to the angle of the attachment being 0° when the attachment is lying flat on the ground at the upper calibration point.

[0084] S402. According to the rocker arm angle sensor data calibrated at the lower calibration point, the theoretical angle of the attachment at the lower calibration point, and the resolution of the rocker arm angle sensor, obtain the fourth target angle of the rocker arm corresponding to the angle of the attachment being 0° at the lower calibration point, and obtain the difference between the fourth target angle and the third target angle.

[0085] S403. According to the rotation angle of the boom, the difference between the fourth target angle and the third target angle, and the second target rotation angle, obtain the second corrected target rotation angle.

[0086] In this step, after taking a certain coefficient for the difference between the fourth target angle and the third target angle according to the rotation angle of the boom, add it to the calculated value of the target angle of the rocker arm. It should be noted that both the third target angle and the fourth target angle are the target rotation angles of the rocker arm, and for clarity, they are respectively used to represent the target rotation angles of the rocker arm corresponding to each different step.

[0087] Optionally, the above step S205 may include: within the rotation angle range of the boom, select a boom angle point that is the same as the calculated target angle of the rocker arm, and calculate the operating current of the rocker arm cylinder.

[0088] Optionally, the above step S207 may include: if the operating current of the current rocker arm cylinder is greater than the calculated value of the operating current of the rocker arm cylinder corresponding to the boom angle point, the operating current of the rocker arm cylinder maintains the current current. If the operating current of the current rocker arm cylinder is less than the calculated value of the operating current of the rocker arm cylinder corresponding to the boom angle point, the operating current of the rocker arm cylinder is equal to the calculated value of the operating current of the rocker arm cylinder. During the process of the boom moving from the current angle point to the next angle point, the controller real-time collects the data of the rocker arm angle sensor, and according to the deviation between the actual value and the target value of the rocker arm sensor, adjusts the operating current of the rocker arm cylinder through an incremental PID controller to adjust the angle of the attachment to approach or equal the target.

[0089] Exemplarily, the above step S207 may include: equally dividing the swing angles of pushing the boom operation handle forward or pulling it backward into several intervals respectively, and each interval corresponds to an operating current of the boom lifting or lowering solenoid valve. As the swing angle of the boom operation handle increases, the corresponding operating current value increases. Since the swing angles of pushing the boom operation handle forward or pulling it backward are equally divided into several intervals respectively, each "gear" is set, and the upper and lower limits of each "gear" are defined, further reducing the calculation and control deviation.

[0090] For clarity, the present invention is combined with specific application scenarios and various formulas to further illustrate the above control method for attachment translation and lifting.

[0091] It is known that the resolution of the rocker arm angle sensor is f c , and the resolution of the boom angle sensor is f a . During the lifting process of the boom 2, the value of the boom sensor increases. During the rotation process of the attachment 4 in the bucket closing direction, the value of the rocker arm sensor increases.

[0092] As Figure 1 shown, the low calibration point is the position where the bucket (taking the attachment 4 as an example of the bucket) is placed flat on the ground, and the rocker arm sensor value recorded at the low calibration point is c0, and the boom sensor value is a0. As Figure 7 shown, the theoretical value of ∠BDC (i.e., ) recorded at the low calibration point is , the theoretical value of ∠DBE (i.e., θ) is θ0, the length of CD is d, the length of BD is b, the length of CE is e, and the length of BE is c.

[0093] First, calculate the angle of the attachment before lifting based on the low calibration point, and the steps are as follows:

[0094] Step 1, find the relative rotation angles of the boom 2 and the rocker arm 5:

[0095] Record that the value of the rocker arm sensor is θ1′ and the value of the boom sensor is α1′. Then the relative rotation angle of the rocker arm is: θ1 = (θ1′ - c0) / f c , and the relative rotation angle of the boom is: α1 = (α1′ - a0) / f a .

[0096] Step 2: Calculate the change in the attachment angle based on the change in the rocker arm angle:

[0097] Let θ = θ0 + θ1.

[0098] According to the trigonometric function relationship:

[0099]

[0100]

[0101] Then

[0102] Step 3: Calculate the attachment angle:

[0103] The angle of the attachment relative to the ground is: If φ1 > 0, the attachment tilts upward along the horizontal plane. If φ1 < 0, the attachment flips downward along the horizontal plane.

[0104] After calculating the angle of the attachment before lifting, calculate the target angle of the rocker arm based on the low - level calibration point. The method is as follows: When the boom 2 is in a certain position, record the value of the boom sensor as α′ x , then the rotation angle of the boom relative to the initial position is: α x =(α′ x - α1′) / f a . To maintain the angle of the bucket relative to the ground unchanged during the boom lifting process, the target rotation angle of the attachment is:

[0105] As Figure 8 shown, calculate the target rotation angle of the rocker arm 5. Let θ = θ0 + θ1 + θ 1x , according to the trigonometric function relationship:

[0106]

[0107]

[0108] Then, θ = ω - δ.

[0109] The target rotation angle of the rocker arm is: θ 1x = θ - θ0 - θ1.

[0110] The rocker arm target voltage value is: θ 1-x = θ 1x * f c + θ1'.

[0111] If θ 1x > 0, the attachment rotates in the bucket - lowering direction; if θ 1x < 0, the attachment rotates in the bucket - retracting direction.

[0112] Correct the rocker arm target angle calculated based on the low - position calibration point. When the boom is at the lifting limit position calculated based on the low - position calibration point and the attachment angle is 0°, the corresponding rocker arm target voltage value is denoted as: θ 01 .

[0113] According to the bucket sensor value and the corresponding theoretical angle recorded at the boom lifting limit position, calculate the lifting limit position. When the attachment angle is 0°, the corresponding rocker arm target voltage value: θ 02 = c2 - φ0 * f c .

[0114] Correct the rocker arm target voltage value according to the following formula:

[0115] θ 1-x = θ 1-x + Δ * (a' x - a0) / (b0 - a0), θ 01 < θ 02

[0116] θ 1-x = θ 1-x - Δ * (a' x - a0) / (b0 - a0), θ 01 > θ 02

[0117] As Figure 2 shown, the high - position calibration point is the boom lifting limit and the attachment bucket - retracting limit. At the high - position calibration point, the attachment angle is denoted as φ1 = φ0, and the boom angle is α1 = 0. Record the rocker arm sensor value as c0 and the boom sensor value as a0. As Figure 7 shown, the theoretical value of ∠BDC at the low - position calibration point is The theoretical value of ∠DBE is θ0. It is known that the length of CD is d, the length of BD is b, the length of CE is e, and the length of BE is c.

[0118] Calculate the initial angle of the attachment before lifting based on the high - position calibration point, and the steps are as follows:

[0119] Step 1, find the relative rotation angle of the boom 2 and the rocker arm 5:

[0120] If the value of the rocker arm sensor is θ1′ and the value of the boom sensor is α1′, then the relative rotation angle of the rocker arm θ1 = (θ1′ - c0) / f c , and the relative rotation angle of the boom α1 = (α1′ - a0) / f a .

[0121] Step 2: Calculate the attachment angle change based on the angle change of the rocker arm relative to the high reference point:

[0122] Let θ = θ0 + θ1.

[0123] According to the trigonometric function relationship:

[0124]

[0125]

[0126] Then

[0127] Step 3: Calculate the angle of the attachment before lifting:

[0128] The angle of the attachment relative to the ground is

[0129] If φ1 > 0, the attachment tilts upward along the horizontal plane; if φ1 < 0, the attachment flips downward along the horizontal plane.

[0130] After calculating the angle of the attachment before lifting, calculate the target angle of the rocker arm based on the high reference point. The method is as follows: When the boom is in a certain position, the value of the boom sensor is α′ x , and the rotation angle of the boom relative to the position before lifting: α x = (α′ x - α1′) / f a . To keep the angle of the bucket relative to the ground unchanged during the lifting process of the boom, the target rotation angle of the attachment:

[0131] As Figure 8 shown, calculate the target rotation angle of the rocker arm. Let θ = θ0 + θ1 + θ 2x , and according to the trigonometric function relationship:

[0132]

[0133]

[0134] Then, θ = ω - δ.

[0135] The target rotation angle of the rocker arm is: θ 2x = θ - θ0 - θ1.

[0136] The target voltage value of the rocker arm is: θ 2-x = θ 2x *f c + θ1'.

[0137] If θ 2x > 0, the attachment rotates in the bucket-lowering direction; if θ 2x < 0, the attachment rotates in the bucket-raising direction.

[0138] After calculating the target angle of the rocker arm based on the high calibration points, the calculated value needs to be corrected. The specific method is as follows:

[0139] First, calculate the target voltage value of the rocker arm corresponding to the attachment in the ground-flat position with the attachment angle being 0 based on the high calibration points, denoted as: θ 03 .

[0140] Then, correct the target voltage value of the rocker arm calculated based on the high calibration points according to the following formula:

[0141] Δ = |θ 03 - c0|

[0142] θ 2-x = θ 2-x + Δ * (a' x - a0) / (b0 - a0), θ 03 < c0

[0143] θ 2-x = θ 2-x - Δ * (a' x - a0) / (b0 - a0), θ 03 > c0

[0144] Furthermore, after calculating the target voltage values of the rocker arm based on the low calibration points and the high calibration points respectively, determine the final target voltage value of the rocker arm according to the boom height. The calculation formula is as follows:

[0145] θ x = θ 1-x * a + θ 2-x * (1 - a)

[0146] a = 2 / 3, a' x < a0 + (b0 - a0) * 2 / 5

[0147] a = 1 / 2, a0 + (b0 - a0) * 2 / 5 <= a' x <= a0 + (b0 - a0) * 3 / 5

[0148] a = 2 / 3, a' x > a0 + (b0 - a0) * 3 / 5

[0149] As described above, the target angle of the rocker arm is determined based on the low calibration point and the high calibration point respectively, and then the final target angle of the rocker arm is jointly determined by the calculated value of the low calibration point and the calculated value of the high calibration point according to the boom angle. This calculation method can effectively reduce the calculation errors caused by the calibration error of the sensor data and the increase of the measurement angle.

[0150] Furthermore, after calculating the target angles of the rocker arm corresponding to different boom angles, it is necessary to calculate the follow-up target values of the rocker arm sensor with the change of the boom angle. That is, according to the relationship between the translational lifting target rotation angle of the rocker arm and the boom rotation angle, the corresponding relationship between the change amount of the rocker arm rotation angle and the change amount of the boom rotation angle is obtained.

[0151] First, select the boom sensor values corresponding to several boom angles at equal intervals, denoted as {x10, x11, x12, ……, x1 n}. Then, according to the angle before the attachment is lifted, calculate the boom sensor values {x10, x11, x12, ……, x1 n}, the corresponding translational lifting target values of the rocker arm sensor {y30, y31, y32, ……, y3 n}, and calculate the follow-up target values of the rocker arm sensor {y40, y41, y42, ……, y4 n-1} when the boom moves from the current sensor value to the next sensor value.

[0152] The calculation method of the follow-up target value of the rocker arm sensor is as follows:

[0153] Denote the position of the low calibration point, ∠GAB = ɑ0, ∠FBA = θ0. When the boom moves to the x1 k-1 position, the relative rotation angle of the boom: Δα = (x1 k-1 - x10) / f a , the relative rotation angle of the rocker arm: Δθ = (y3 k-1 - c0) / f c .

[0154] As Figure 9 shown, according to the trigonometric function relationship:

[0155]

[0156]

[0157]

[0158]

[0159] When the boom moves from the x1 k-1 position to x1k Position, the length of FG remains unchanged. According to the above calculation formula, ∠FBG(x1 k ), ∠GBA(x1 k ) can be calculated.

[0160] Then, the follow-up target value of the rocker arm sensor is:

[0161] y4 k =(∠FBG(x1 k ) + ∠GBA(x1 k ) - θ0) * f c + c0.

[0162] Furthermore, determine the relationship between the operating current of the rocker arm cylinder and the operating current of the boom cylinder according to the change amount of the boom angle and the change amount of the rocker arm angle. The specific method is as follows:

[0163] When the boom sensor value is x1 k-1 , the angle change amount of boom 2: α1 = (x1 k-1 - x10) / f a . At this time, the length of the boom cylinder is denoted as L a . When the rocker arm sensor value is y3 k-1 , the angle change amount of the boom θ1 = (y3 k-1 - y10) / f c . At this time, the length of the rocker arm cylinder is denoted as L b . Assume that boom 2 moves from the sensor value x1 k-1 position to x1 k position, then the angle change amount of boom 2 Δα = (x1 k - x1 k-1 ) / f a , and the corresponding change amount of the boom cylinder length is denoted as L ax . The angle change amount of the rocker arm sensor from the follow-up target value to the translation and lifting target value: Δθ = (y3 k - y4 k ) / f c . The corresponding change amount of the rocker arm cylinder length is denoted as L bx .

[0164] As Figure 10 and Figure 11 shown, denote the low position calibration point ∠GBF = θ0, ∠HAI = α0. Then according to the trigonometric function relationship, there are:

[0165]

[0166]

[0167]

[0168]

[0169] Denote the areas of the small chamber and the large chamber of the rocker arm cylinder as s1 and s2 respectively; denote the areas of the small chamber and the large chamber of the boom cylinder as s3 and s4 respectively. The characteristics of the solenoid valves controlling the boom cylinder and the rocker arm cylinder are the same.

[0170] During horizontal lifting, if the boom performs a lifting operation and the boom lifting current is Cu boom , and if the rocker arm needs to dump when moving to the target position during the boom lifting process, the action current of the rocker arm cylinder is:

[0171] Cr buck =(L bx / L ax )*(s1 / s4)*Cu boom

[0172] If the rocker arm needs to gather when moving to the target position during the boom lifting process, the action current of the rocker arm cylinder is:

[0173] Cr buck =(L bx / L ax )*(s2 / s4)*Cu boom

[0174] During horizontal lifting, if the boom performs a lowering operation and the boom lowering current is Cd boom , and if the rocker arm needs to dump when moving to the target position during the boom lowering process, the action current of the rocker arm cylinder is:

[0175] Cr buck =(L bx / L ax )*(s1 / s3)*Cd boom

[0176] If the rocker arm needs to gather when moving to the target position during the boom lowering process, the action current of the rocker arm cylinder is:

[0177] Cr buck =(L bx / L ax )*(s2 / s3)*Cd boom

[0178] Furthermore, during the horizontal lifting process, the action current of the rocker arm cylinder is further adjusted by the PID algorithm. As Figure 12 shown, the boom 2 moves from the sensor value x1 k-1 position to x1 kDuring the process of the position, according to the deviation between the actual value and the target value of the rocker arm sensor, the current of the rocker arm oil cylinder is adjusted by an incremental PI controller or an incremental PID controller to adjust the angle of the attachment. The calculation formula of the rocker arm oil cylinder current is as follows:

[0179] i e (k)=i e (k - 1)+kp*(Δθ(k)-Δθ(k - 1))+Ki*Δθ(k)

[0180] Where, i e (k) is the operating current of the rocker arm oil cylinder in the current sampling period; i e (k - 1) is the operating current of the rocker arm oil cylinder in the previous sampling period; Δθ(k) is the deviation of the rocker arm sensor value in the current sampling period; Δθ(k - 1) is the deviation of the rocker arm sensor value in the current sampling period; kp is the proportional link; Ki is the integral link.

[0181] Furthermore, when the boom moves to the x1 k position, if the operating current of the current rocker arm oil cylinder is greater than the calculated value Cr buck , then the operating current of the rocker arm oil cylinder maintains the current current. If the operating current of the current rocker arm oil cylinder is less than the calculated value Cr buck , then the rocker arm oil cylinder current is equal to Cr buck .

[0182] Figure 13 FIG. is a schematic structural diagram of a controller provided by an embodiment of the present invention. Figure 13 The controller 60 shown is merely an example and should not impose any limitation on the functions and usage scope of the embodiments of the present invention. With reference to Figure 1 , Figure 2 and Figure 13 , the control system for the translation and lifting of the attachment includes a rocker arm angle sensor, a boom angle sensor, and a controller 60. The rocker arm angle sensor is configured to detect the rotation angle of the rocker arm, the boom angle sensor is configured to detect the rotation angle of the boom, and both the rocker arm angle sensor and the boom angle sensor are electrically connected to the controller 60. The controller 60 is presented in the form of a general computing device. The components of this controller 60 may include, but are not limited to: one or more processors 601, a system memory 602, and a bus 603 connecting different system components (including the system memory 602 and the processor 601).

[0183] The bus 603 represents one or more of several types of bus architectures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processor, or a local bus using any of the various bus architectures. By way of example, these architectures include, but are not limited to, Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MAC) bus, Enhanced ISA bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnect (PCI) bus.

[0184] The controller 60 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by the controller 60, including both volatile and nonvolatile media, removable and non-removable media.

[0185] The system memory 602 can include computer system readable media in the form of volatile memory, such as random access memory (RAM) 604 and / or cache memory 605. The controller 60 can further include other removable / non-removable, volatile / nonvolatile computer system storage media. By way of example only, a storage system 606 can be used for reading from and writing to a non-removable, nonvolatile magnetic medium (commonly referred to as a "hard disk drive"). Although Figure 5 not shown in the figures, a disk drive for reading from and writing to a removable nonvolatile disk (such as a "floppy disk"), and an optical disk drive for reading from and writing to a removable nonvolatile optical disk (such as a CD-ROM, DVD-ROM, or other optical medium) can be provided. In these instances, each drive can be connected to the bus 603 by one or more data media interfaces. The system memory 602 can include at least one program product having a set (e.g., at least one) of program modules that are configured to carry out the functions of the embodiments of the present invention.

[0186] A program / utility 608 having a set (at least one) of program modules 607 can be stored, for example, in the system memory 602, and such program modules 607 include, but are not limited to, an operating system, one or more application programs, other program modules, and program data, each of which examples or some combination thereof may include an implementation of a network environment. The program modules 607 generally carry out the functions and / or methods of the embodiments described herein.

[0187] The controller 60 can also communicate with one or more external devices 609 (such as a keyboard, a pointing device, a display 613, etc.), and can also communicate with one or more devices that enable a user to interact with the device, and / or communicate with any device that enables the controller 60 to communicate with one or more other computing devices (such as a network card, a modem, etc.). Such communication can be carried out through the input / output (I / O) interface 611. Moreover, the controller 60 can also communicate with one or more networks (such as a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) through the network adapter 612. As Figure 13 shown, the network adapter 612 communicates with other modules of the controller 60 through the bus 603. It should be understood that although not shown in the figure, other hardware and / or software modules can be used in combination with the controller 60, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems, etc.

[0188] The processor 601 executes various functional applications and data processing by running the programs stored in the system memory 602, such as implementing the control method provided by the embodiments of the present invention.

[0189] Note that the above is only the preferred embodiment of the present invention and the applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments, combinations with each other, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A control method for the translation and lifting of attachments, characterized in that, Including: Obtaining a first target rotation angle of the swing arm corresponding to the boom rotation angle according to the low calibration point sensor data, and obtaining a second target rotation angle of the swing arm corresponding to the boom rotation angle according to the high calibration point sensor data; Correcting the first target rotation angle according to the high calibration point sensor data to obtain a first corrected target rotation angle, and correcting the second target rotation angle according to the low calibration point sensor data to obtain a second corrected target rotation angle; Obtaining a translational lifting target rotation angle of the swing arm according to the rotation angle of the boom, the first corrected target rotation angle, and the second corrected target rotation angle; Wherein, correcting the second target rotation angle according to the low calibration point sensor data to obtain a second corrected target rotation angle includes: Obtaining a target angle three of the swing arm corresponding to the attachment angle of 0° when the attachment is on the ground and leveled according to the high calibration point; Obtaining a target angle four of the swing arm corresponding to the attachment angle of 0° according to the swing arm angle sensor data calibrated by the low calibration point, the theoretical angle of the low calibration point attachment, and the resolution of the swing arm angle sensor, and obtaining the difference between the target angle four and the target angle three; Obtaining the second corrected target rotation angle according to the rotation angle of the boom, the difference between the target angle four and the target angle three, and the second target rotation angle.

2. The control method according to claim 1, wherein Obtaining a translational lifting target rotation angle of the swing arm according to the rotation angle of the boom, the first corrected target rotation angle, and the second corrected target rotation angle includes: Weightedly adding the first corrected target rotation angle and the second corrected target rotation angle according to the rotation angle of the boom as the translational lifting target rotation angle.

3. The control method according to claim 1, wherein After obtaining the translational lifting target rotation angle of the swing arm according to the rotation angle of the boom, the first corrected target rotation angle, and the second corrected target rotation angle, it further includes: Obtaining the corresponding relationship between the change in the rotation angle of the swing arm and the change in the rotation angle of the boom according to the relationship between the translational lifting target rotation angle of the swing arm and the rotation angle of the boom; Obtaining the corresponding relationship between the operating current of the swing arm cylinder and the operating current of the boom cylinder according to the corresponding relationship between the change in the rotation angle of the swing arm and the change in the rotation angle of the boom.

4. The control method according to claim 3, characterized in that, After obtaining the corresponding relationship between the operating current of the swing arm cylinder and the operating current of the boom cylinder according to the corresponding relationship between the change in the rotation angle of the swing arm and the change in the rotation angle of the boom, it further includes: During the translational lifting process, the operating current of the boom cylinder is obtained in real time; the operating current of the swing arm cylinder is obtained according to the corresponding relationship between the current operating current of the boom cylinder and the calculated value of the operating current of the swing arm cylinder.

5. The control method according to claim 4, characterized in that, After obtaining the operating current of the swing arm cylinder according to the corresponding relationship between the current operating current of the boom cylinder and the calculated value of the operating current of the swing arm cylinder, it further includes: Controlling the operating current of the swing arm cylinder so that the difference between the rotation angle of the swing arm and the translational lifting target rotation angle is less than a preset value.

6. The control method according to claim 1, wherein Correcting the first target rotation angle according to the high calibration point sensor data to obtain a first corrected target rotation angle includes: Obtain the first target angle of the rocker arm corresponding to the angle of the attachment being 0° according to the low calibration point; According to the rocker arm angle sensor data calibrated by the high calibration point, the theoretical angle of the attachment at the high calibration point, and the resolution of the rocker arm angle sensor, obtain the second target angle of the rocker arm corresponding to the angle of the attachment being 0° at the high calibration point, and obtain the difference between the second target angle and the first target angle; According to the rotation angle of the boom, the difference between the second target angle and the first target angle, and the first target rotation angle, obtain the first corrected target rotation angle.

7. The control method according to claim 1, wherein When obtaining the first target rotation angle of the rocker arm corresponding to the rotation angle of the boom according to the low calibration point sensor data and the second target rotation angle of the rocker arm corresponding to the rotation angle of the boom according to the high calibration point sensor data, it further includes: Select a number of boom angle points at equal angles within the rotation angle range of the boom for calculating the target angle of the rocker arm, and calculate the target angle of the rocker arm between two boom angle points by linear interpolation.

8. The control method according to claim 4, characterized in that Obtain the operating current of the rocker arm cylinder according to the corresponding relationship between the current operating current of the boom cylinder and the calculated value of the operating current of the rocker arm cylinder, including: If the current operating current of the rocker arm cylinder is greater than the calculated value of the operating current of the rocker arm cylinder corresponding to the boom angle point, the operating current of the rocker arm cylinder maintains the current current; If the current operating current of the rocker arm cylinder is less than the calculated value of the operating current of the rocker arm cylinder corresponding to the boom angle point, the operating current of the rocker arm cylinder is equal to the calculated value of the operating current of the rocker arm cylinder.

9. A control system for the translation and lifting of attachments, characterized in that, It includes a rocker arm angle sensor, a boom angle sensor, and a controller. The rocker arm angle sensor is configured to detect the rotation angle of the rocker arm, the boom angle sensor is configured to detect the rotation angle of the boom, both the rocker arm angle sensor and the boom angle sensor are electrically connected to the controller, and the controller includes: One or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the control method as described in any one of claims 1-8.

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