Control method and system of multi-connecting-rod mechanism, electronic equipment and storage medium

Abstract

The invention discloses a control method and system of a multi-connecting-rod mechanism, electronic equipment and a storage medium, and the multi-connecting-rod mechanism comprises a plurality of connecting rods which are connected with one another and a linear execution mechanism which is used for driving the connecting rods to move. The method comprises the steps of obtaining an initial change trend of an angular velocity of a target connecting rod according to a corresponding relation between a determined moving stroke of the linear actuator and a pitch angle of the target connecting rod when the linear actuator moves at a constant speed; and the moving speed of the linear execution mechanism is adjusted according to the initial change trend of the angular speed, so that the adjusted real-time change trend of the angular speed of the target connecting rod is more stable than the initial change trend. The moving speed of the linear executing mechanism is adjusted according to the initial change trend of the angular speed of the target connecting rod when the linear executing mechanism moves at the constant speed, so that the real-time change trend of the adjusted angular speed is more stable than the initial change trend, the control efficiency of the multi-connecting-rod mechanism is improved, and the control cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-link mechanisms, and in particular to a control method, system, electronic equipment and storage medium for a multi-link mechanism. Background Art

[0002] If you want to achieve the transmission effect of flipping, pitching or rotating within a certain angle at the load end, a multi-link form is generally used. However, due to the multi-link form, different link lengths and fulcrum positions, the angular velocity fluctuation range of the load end is very large when the motor moves at a constant speed. In order to reduce the angular velocity fluctuation at the load end, it is generally considered to add a speed sensor at the load end, but this will increase the hardware cost. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of high cost and complicated operation in the prior art method of reducing the angular velocity change rate of the load end of a multi-link mechanism, and to provide a control method, system, electronic device and storage medium for a multi-link mechanism.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] A first aspect of the present invention provides a control method for a multi-link mechanism, wherein the multi-link mechanism comprises a plurality of interconnected links and a linear actuator for driving the links to move, the control method comprising:

[0006] Determining the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target connecting rod;

[0007] According to the corresponding relationship, an initial change trend of the angular velocity of the target connecting rod when the linear actuator moves at a constant speed is obtained;

[0008] The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0009] Preferably, the control method further includes:

[0010] The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than a preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

[0011] Preferably, the angular velocity of the target link is obtained based on a derivative operation of a pitch angle of the target link.

[0012] Preferably, the step of adjusting the moving speed of the linear actuator according to the initial change trend of the angular velocity so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend comprises:

[0013] Dividing the moving stroke of the linear actuator into a plurality of sub-strokes;

[0014] Obtaining each initial change trend of the angular velocity of the target connecting rod in each sub-stroke;

[0015] The moving speed of the linear actuator in each sub-stroke is adjusted according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0016] Preferably, the control method further includes:

[0017] Obtaining the maximum angular velocity and the root mean square angular velocity of the target connecting rod;

[0018] The angular velocity change rate of the target connecting rod is calculated according to the maximum angular velocity and the root mean square of the angular velocity.

[0019] Preferably, the multi-link mechanism is a four-link mechanism, which includes a first link, a second link, a third link and a fourth link, the second link is the target link, and the first link, the second link, the third link, the fourth link and the linear actuator are connected to each other in sequence.

[0020] Preferably, both end points of the second connecting rod are not fixed, and the first connecting rod, the third connecting rod and the fourth connecting rod all have one end point fixed and the other end point not fixed.

[0021] A second aspect of the present invention provides a control system for a multi-link mechanism, wherein the multi-link mechanism comprises a plurality of interconnected links and a linear actuator for driving the links to move, and the control system comprises:

[0022] A first determination module is used to determine the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target connecting rod;

[0023] A second determination module is used to obtain, according to the corresponding relationship, an initial change trend of the angular velocity of the target connecting rod when the linear actuator moves at a constant speed;

[0024] The first adjustment module is used to adjust the moving speed of the linear actuator according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0025] Preferably, the control system further comprises:

[0026] The second adjustment module is used to adjust the moving speed of the linear actuator according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than a preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

[0027] Preferably, the angular velocity of the target link is obtained based on a derivative operation of a pitch angle of the target link.

[0028] Preferably, the first adjustment module includes:

[0029] A dividing unit, used for dividing the moving stroke of the linear actuator into a plurality of sub-strokes;

[0030] An acquisition unit, used for acquiring each initial change trend of the angular velocity of the target connecting rod in each sub-stroke;

[0031] The adjustment unit is used to adjust the moving speed of the linear actuator in each sub-stroke according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0032] Preferably, the control system further comprises:

[0033] A first acquisition module, used to acquire the maximum angular velocity and the root mean square angular velocity of the target connecting rod;

[0034] The second acquisition module is used to calculate the angular velocity change rate of the target connecting rod according to the maximum angular velocity and the root mean square of the angular velocity.

[0035] Preferably, the multi-link mechanism is a four-link mechanism, which includes a first link, a second link, a third link and a fourth link, the second link is the target link, and the first link, the second link, the third link, the fourth link and the linear actuator are connected to each other in sequence.

[0036] Preferably, both end points of the second connecting rod are not fixed, and the first connecting rod, the third connecting rod and the fourth connecting rod all have one end point fixed and the other end point not fixed.

[0037] A third aspect of the present invention provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and used to run on the processor, wherein the processor implements the control method of the multi-link mechanism as described in the first aspect when executing the computer program.

[0038] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the control method of the multi-link mechanism as described in the first aspect is implemented.

[0039] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0040] The positive and progressive effects of the present invention are:

[0041] The present invention can reduce the angular velocity change rate of the target link of the multi-link mechanism without adding a speed sensor to the target link. Specifically, the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link is determined; the initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed is obtained according to the corresponding relationship; the moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend, thereby improving the control efficiency of the multi-link mechanism and reducing the control cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 Flow chart of the control method of the multi-link mechanism according to embodiment 1 of the present invention.

[0043] Figure 2 This is a flow chart of step 103 of the method for controlling a multi-link mechanism according to embodiment 1 of the present invention.

[0044] Figure 3 It is a first structural schematic diagram of the multi-link mechanism of embodiments 1 and 2 of the present invention.

[0045] Figure 4 It is a second structural schematic diagram of the multi-link mechanism of embodiments 1 and 2 of the present invention.

[0046] Figure 5 Schematic diagram of the initial change trend of the angular velocity of the target link of the multi-link mechanism of Examples 1 and 2 of the present invention.

[0047] Figure 6 Schematic diagram of the real-time change trend of the angular velocity of the target link of the multi-link mechanism of Examples 1 and 2 of the present invention.

[0048] Figure 7 This is a module schematic diagram of a control system of a multi-link mechanism according to Example 2 of the present invention.

[0049] Figure 8 This is a schematic diagram of the structure of an electronic device for implementing a control method for a multi-link mechanism according to Embodiment 3 of the present invention. DETAILED DESCRIPTION

[0050] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples.

[0051] Example 1

[0052] This embodiment provides a control method for a multi-link mechanism, wherein the multi-link mechanism includes a plurality of interconnected links and a linear actuator for driving the links to move. Figure 1 As shown, the control method includes:

[0053] Step 101, determining the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target connecting rod;

[0054] In this embodiment, when the movement stroke of the linear actuator changes uniformly, the change of the pitch angle of the target link is non-uniform.

[0055] It should be noted that the pitch angle of the target link refers to the angle between the target link and the horizontal plane.

[0056] Step 102: obtaining, according to the corresponding relationship, an initial change trend of the angular velocity of the target connecting rod when the linear actuator moves at a constant speed;

[0057] In an optional embodiment, the angular velocity of the target link is obtained based on a derivative operation of the pitch angle of the target link.

[0058] Step 103: adjusting the moving speed of the linear actuator according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0059] In an optional embodiment, the control method further includes:

[0060] The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than the preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

[0061] In this embodiment, the preset angular velocity change rate is set according to actual conditions and is not specifically limited here.

[0062] In an optional embodiment, if Figure 2 As shown, step 103 includes:

[0063] Step 1031, dividing the moving stroke of the linear actuator into a plurality of sub-strokes;

[0064] Step 1032, obtaining each initial change trend of the angular velocity of the target connecting rod in each sub-stroke;

[0065] Step 1033: adjusting the moving speed of the linear actuator in each sub-stroke according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0066] In this embodiment, in order to perform more precise and accurate control on the multi-link mechanism, specifically, by dividing the moving stroke of the linear actuator into multiple sub-strokes, the moving speed of the linear actuator in each sub-stroke is adjusted according to each initial change trend of the angular velocity of the target link in each sub-stroke, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend.

[0067] In an optional embodiment, the control method further includes:

[0068] Obtain the maximum angular velocity and the root mean square angular velocity of the target link;

[0069] The angular velocity change rate of the target link is calculated based on the maximum angular velocity and the root mean square of the angular velocity.

[0070] In an optional embodiment, the expression for the angular velocity change rate of the target link is calculated based on the maximum angular velocity and the root mean square of the angular velocity as shown in formula (1):

[0071]

[0072] Wherein, M represents the rate of change of the angular velocity of the target link; F represents the maximum angular velocity of the target link; and N represents the root mean square of the angular velocity of the target link.

[0073] In an optional embodiment, if Figure 3 As shown, the multi-link mechanism is a four-link mechanism, which includes a first link L1, a second link L2, a third link L3 and a fourth link L4, the second link L2 is a target link, the first link L1, the second link L2, the third link L3, the fourth link L4 and the linear actuator L5 are connected to each other in sequence, the two end points of the second link L2 are not fixed, the first link L1, the third link L3 and the fourth link L4 are all fixed at one end point and the other end point is not fixed; one end point of the linear actuator L5 is fixed, and the other end point is connected to the fourth link L4. In a specific real-time process, when the moving distance S1 corresponding to the moving stroke of the linear actuator L5 changes, the first link L1 and the third link L3 rotate around their respective fixed points, as shown in FIG. Figure 3 As shown by the dotted circle in the middle, the second link L2 will also rotate, and the motion trajectories of the two end points of the second link L2 are Figure 3 The expression for determining the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link is shown in formula (2):

[0074]

[0075] Wherein, α represents the pitch angle of the target link, S1 represents the moving distance corresponding to the moving stroke of the linear actuator, L1 represents the length of the first link, L2 represents the length of the second link, L3 represents the length of the third link, L4 represents the length of the fourth link, L5 represents the length of the linear actuator, L6 represents the length between the fixed end point of the first link and the intersection of the second link and the third link, L7 represents the length between the fixed end point of the first link and the intersection of the third link and the fourth link, L8 represents the length between the fixed end point of the linear actuator and the intersection of the third link and the fourth link, ∠B1 represents the angle between the line connecting the fixed end point of the first link and the intersection of the third link and the fourth link and the straight line where the third link is located, ∠B2 represents the angle between the straight line where the third link is located and the straight line where the fourth link is located, and ∠B3 represents the angle between the line connecting the fixed end point of the linear actuator and the intersection of the third link and the fourth link and the vertical line with the intersection of the third link and the fourth link as the starting point and the horizontal plane.

[0076] Specifically, for example, Figure 4 As shown, A represents the intersection of the first link L1 and the second link L2, B represents the intersection of the second link L2 and the third link L3, C represents the intersection of the third link L3 and the fourth link L4, and C is also the fixed end point of the third link L3 and the fourth link L4, F represents the intersection of the fourth link L4 and the moving distance S1 corresponding to the moving stroke of the linear actuator, I represents the fixed end point of the first link L1, and G represents the fixed end point of the linear actuator. Figure 4 As shown, CE is the extension of BC, CH is perpendicular to GH, CD is parallel to GH, and the pitch angle α of the target link can be expressed as:

[0077]

[0078] like Figure 4 As shown, since the positions of the fixed end points I, C, and G are known, the angles of ∠ICD and ∠HCG are known. In addition, since the third link L3, the fourth link L4, and ∠BCF are known, and CE is the extension line of BC, ∠BCF is known. When the moving distance S1 corresponding to the moving stroke of the linear actuator changes, ∠FCG also changes. It can be known from the cosine law that:

[0079]

[0080] From the above formula, we can know that:

[0081]

[0082] From the law of cosines we know that:

[0083]

[0084]

[0085]

[0086] From the above formula, we can know that:

[0087]

[0088] Since the moving distance S1 and α corresponding to the moving stroke of the linear actuator in the above formula are variable, and other parameters are known, the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link can be determined by the above formula.

[0089] In the specific implementation process, Figure 3 As shown in FIG. 1 , since the rotation center of the second link L2 is fixed, when the moving distance S1 corresponding to the moving stroke of the linear actuator L5 changes uniformly (i.e., the moving speed dS1 / dt of the linear actuator is a constant), the change of the pitch angle α of the target link is non-uniform (i.e., the angular velocity dα / dt of the target link is a constant). Through kinematics, it can be obtained that when the linear actuator moves at a constant speed, the initial change trend of the angular velocity of the target link is as follows: Figure 5 As shown;

[0090] Depend on Figure 5 It can be seen that when the linear actuator moves at a constant speed, the angular velocity of the target link presents an initial U-shaped change trend with large ends and small in the middle. This indicates that when the moving speed of the linear actuator is constant, the angular velocity of the target link presents an initial change trend of large-small-large.

[0091] like Figure 6 As shown, in order to perform more precise and accurate control on the multi-link mechanism, the present embodiment divides the moving stroke of the linear actuator into multiple sub-strokes, and monitors the length of each sub-stroke and the time required for the linear actuator to move in each sub-stroke by a sensor arranged on the linear actuator, so as to obtain the moving speed of the linear actuator in each sub-stroke; it should be noted that the moving speed of the linear actuator in each sub-stroke may be the same or different, so that in the entire moving stroke, the moving speed of the linear actuator presents an inverted U shape, so that the angular velocity of the target link tends to be constant, and furthermore, the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend. Specifically, by Figure 5 to Figure 6 The change of can intuitively show that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend. Figure 5 and Figure 6 The ordinate in represents the angular velocity of the target link, and the abscissa represents the moving data points. Further, Figure 5 and Figure 6 The waveform in the figure is obtained by measuring the displacement data of three fixed points on the connecting rod in space with a three-dimensional motion measurement system, and then processing the data. Therefore, the horizontal axis has no unit and can be understood as a moving data point. For example, the moving data point measured by the three-dimensional motion measurement system at the beginning is 0, and the moving data point when it stops measuring is 4000. 0 or 4000 is just a scale. Assuming that the three-dimensional motion measurement system collects one data in 0.01 seconds, 4000 means that 4000 data are collected, and the total time is 40s.

[0092] It should be noted that this embodiment does not need to use a velocity sensor or an inclination sensor to measure the angular velocity or angle of the target link of the multi-link mechanism, and thus does not need to perform closed-loop velocity control, thereby reducing the selection requirements for the linear actuator.

[0093] In addition, the more segments the linear actuator's moving stroke is divided into, the smaller the angular velocity change rate of the target link is, and the more constant the angular velocity of the target link is, that is, the angular velocity change rate of the target link is negatively correlated with the number of the several stroke segments.

[0094] This embodiment can reduce the angular velocity change rate of the target link of the multi-link mechanism without adding a speed sensor to the target link. Specifically, the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link is determined; the initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed is obtained according to the corresponding relationship; the moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend, thereby improving the control efficiency of the multi-link mechanism and reducing the control cost.

[0095] Example 2

[0096] This embodiment provides a control system for a multi-link mechanism, which includes a plurality of interconnected links and a linear actuator for driving the links to move. Figure 7 As shown, the control system includes: a first determination module 21, a second determination module 22, and a first adjustment module 23;

[0097] A first determination module 21 is used to determine the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target connecting rod;

[0098] In this embodiment, when the movement stroke of the linear actuator changes uniformly, the change of the pitch angle of the target link is non-uniform.

[0099] It should be noted that the pitch angle of the target link refers to the angle between the target link and the horizontal plane.

[0100] A second determination module 22 is used to obtain, according to the corresponding relationship, an initial change trend of the angular velocity of the target connecting rod when the linear actuator moves at a constant speed;

[0101] In an optional embodiment, the angular velocity of the target link is obtained based on a derivative operation of the pitch angle of the target link.

[0102] The first adjustment module 23 is used to adjust the moving speed of the linear actuator according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0103] In an optional embodiment, if Figure 7 As shown, the control system further includes: a second adjustment module 24;

[0104] The second adjustment module 24 is used to adjust the moving speed of the linear actuator according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than the preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

[0105] In this embodiment, the preset angular velocity change rate is set according to actual conditions and is not specifically limited here.

[0106] In an optional embodiment, if Figure 7 As shown, the first adjustment module 23 includes: a division unit 231, an acquisition unit 232, and an adjustment unit 233;

[0107] A dividing unit 231, used for dividing the moving stroke of the linear actuator into a plurality of sub-strokes;

[0108] An acquisition unit 232 is used to acquire each initial change trend of the angular velocity of the target connecting rod in each sub-stroke;

[0109] The adjustment unit 233 is used to adjust the moving speed of the linear actuator in each sub-stroke according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0110] In this embodiment, in order to perform more precise and accurate control on the multi-link mechanism, specifically, by dividing the moving stroke of the linear actuator into multiple sub-strokes, the moving speed of the linear actuator in each sub-stroke is adjusted according to each initial change trend of the angular velocity of the target link in each sub-stroke, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend.

[0111] In an optional embodiment, if Figure 7 As shown, the control system further includes: a first acquisition module 25 and a second acquisition module 26;

[0112] A first acquisition module 25, used to acquire the maximum angular velocity and the root mean square angular velocity of the target connecting rod;

[0113] The second acquisition module 26 is used to calculate the angular velocity change rate of the target link according to the maximum angular velocity and the root mean square of the angular velocity.

[0114] In an optional embodiment, the expression for the angular velocity change rate of the target link is calculated based on the maximum angular velocity and the root mean square of the angular velocity as shown in formula (1) in Example 1.

[0115] In an optional embodiment, if Figure 3 As shown, the multi-link mechanism is a four-link mechanism, which includes a first link L1, a second link L2, a third link L3 and a fourth link L4, the second link L2 is a target link, the first link L1, the second link L2, the third link L3, the fourth link L4 and the linear actuator L5 are connected to each other in sequence, the two end points of the second link L2 are not fixed, the first link L1, the third link L3 and the fourth link L4 are all fixed at one end point and the other end point is not fixed; one end point of the linear actuator L5 is fixed, and the other end point is connected to the fourth link L4. In a specific real-time process, when the moving distance S1 corresponding to the moving stroke of the linear actuator L5 changes, the first link L1 and the third link L3 rotate around their respective fixed points, as shown in FIG. Figure 3 As shown by the dotted circle in the middle, the second link L2 will also rotate, and the motion trajectories of the two end points of the second link L2 are Figure 3 The expression for determining the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target connecting rod is shown in formula (2) in Example 1:

[0116] Specifically, for example, Figure 4 As shown, A represents the intersection of the first link L1 and the second link L2, B represents the intersection of the second link L2 and the third link L3, C represents the intersection of the third link L3 and the fourth link L4, and C is also the fixed end point of the third link L3 and the fourth link L4, F represents the intersection of the fourth link L4 and the moving distance S1 corresponding to the moving stroke of the linear actuator, I represents the fixed end point of the first link L1, and G represents the fixed end point of the linear actuator. Figure 4As shown, CE is the extension line of BC, CH is perpendicular to GH, CD is parallel to GH, and the expression of the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target connecting rod can be deduced from formulas (1.1)-(1.7) in Example 1.

[0117] In the specific implementation process, Figure 3 As shown in FIG. 1 , since the rotation center of the second link L2 is fixed, when the moving distance S1 corresponding to the moving stroke of the linear actuator L5 changes uniformly (i.e., the moving speed dS1 / dt of the linear actuator is a constant), the change of the pitch angle α of the target link is non-uniform (i.e., the angular velocity dα / dt of the target link is a constant). Through kinematics, it can be obtained that when the linear actuator moves at a constant speed, the initial change trend of the angular velocity of the target link is as follows: Figure 5 As shown;

[0118] Depend on Figure 5 It can be seen that when the linear actuator moves at a constant speed, the angular velocity of the target link presents an initial U-shaped change trend with large ends and small in the middle. This indicates that when the moving speed of the linear actuator is constant, the angular velocity of the target link presents an initial change trend of large-small-large.

[0119] like Figure 6 As shown, in order to perform more precise and accurate control on the multi-link mechanism, the present embodiment divides the moving stroke of the linear actuator into multiple sub-strokes, and monitors the length of each sub-stroke and the time required for the linear actuator to move in each sub-stroke by a sensor arranged on the linear actuator, so as to obtain the moving speed of the linear actuator in each sub-stroke; it should be noted that the moving speed of the linear actuator in each sub-stroke may be the same or different, so that in the entire moving stroke, the moving speed of the linear actuator presents an inverted U shape, so that the angular velocity of the target link tends to be constant, and furthermore, the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend. Specifically, by Figure 5 to Figure 6 The change of can intuitively show that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend. Figure 5 and Figure 6 The ordinate in represents the angular velocity of the target link, and the abscissa represents the moving data points. Further, Figure 5 and Figure 6The waveform in the figure is obtained by measuring the displacement data of three fixed points on the connecting rod in space with a three-dimensional motion measurement system, and then processing the data. Therefore, the horizontal axis has no unit and can be understood as a moving data point. For example, the moving data point measured by the three-dimensional motion measurement system at the beginning is 0, and the moving data point when it stops measuring is 4000. 0 or 4000 is just a scale. Assuming that the three-dimensional motion measurement system collects one data in 0.01 seconds, 4000 means that 4000 data are collected, and the total time is 40s.

[0120] It should be noted that this embodiment does not need to use a velocity sensor or an inclination sensor to measure the angular velocity or angle of the target link of the multi-link mechanism, and thus does not need to perform closed-loop velocity control, thereby reducing the selection requirements for the linear actuator.

[0121] In addition, the more segments the linear actuator's moving stroke is divided into, the smaller the angular velocity change rate of the target link is, and the more constant the angular velocity of the target link is, that is, the angular velocity change rate of the target link is negatively correlated with the number of the several stroke segments.

[0122] This embodiment can reduce the angular velocity change rate of the target link of the multi-link mechanism without adding a speed sensor to the target link. Specifically, the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link is determined; the initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed is obtained according to the corresponding relationship; the moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend, thereby improving the control efficiency of the multi-link mechanism and reducing the control cost.

[0123] Example 3

[0124] Figure 8 This is a schematic diagram of the structure of an electronic device provided in Example 3 of the present invention. The electronic device includes a memory, a processor, and a computer program stored in the memory and used to run on the processor. When the processor executes the program, the control method of the multi-link mechanism of Example 1 is implemented. Figure 8 The electronic device 30 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0125] like Figure 8 As shown, the electronic device 30 may be in the form of a general-purpose computing device, for example, it may be a server device. The components of the electronic device 30 may include, but are not limited to: at least one processor 31, at least one memory 32, and a bus 33 connecting different system components (including the memory 32 and the processor 31).

[0126] The bus 33 includes a data bus, an address bus, and a control bus.

[0127] The memory 32 may include a volatile memory, such as a random access memory (RAM) 321 and / or a cache memory 322 , and may further include a read-only memory (ROM) 323 .

[0128] The memory 32 may also include a program / utility 325 having a set (at least one) of program modules 324, such program modules 324 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0129] The processor 31 executes various functional applications and data processing by running the computer programs stored in the memory 32, such as the control method of the multi-link mechanism of the first embodiment of the present invention.

[0130] The electronic device 30 may also communicate with one or more external devices 34 (e.g., keyboards, pointing devices, etc.). Such communication may be performed via an input / output (I / O) interface 35. Furthermore, the model generating device 30 may also communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter 36. Figure 8 As shown, the network adapter 36 communicates with other modules of the model-generated device 30 via the bus 33. It should be understood that, although not shown in the figure, other hardware and / or software modules can be used in conjunction with the model-generated device 30, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID (disk array) systems, tape drives, and data backup storage systems, etc.

[0131] It should be noted that although several units / modules or sub-units / modules of the electronic device are mentioned in the above detailed description, this division is merely exemplary and not mandatory. In fact, according to an embodiment of the present invention, the features and functions of two or more units / modules described above can be embodied in one unit / module. Conversely, the features and functions of one unit / module described above can be further divided into multiple units / modules to be embodied.

[0132] Example 4

[0133] This embodiment provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the control method of the multi-link mechanism provided in Embodiment 1 is implemented.

[0134] The readable storage medium may include but is not limited to: a portable disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical storage device, a magnetic storage device or any suitable combination of the above.

[0135] In a possible implementation manner, the present invention may also be implemented in the form of a program product, which includes a program code. When the program product is run on a terminal device, the program code is used to enable the terminal device to execute the control method for the multi-link mechanism described in Example 1.

[0136] Among them, the program code for executing the present invention can be written in any combination of one or more programming languages, and the program code can be executed completely on the user device, partially on the user device, as an independent software package, partially on the user device and partially on a remote device, or completely on the remote device.

[0137] Although the specific embodiments of the present invention are described above, it should be understood by those skilled in the art that this is only for illustration and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A control method for a multi-link mechanism, characterized in that: The multi-link mechanism includes a plurality of interconnected links and a linear actuator for driving the links to move. The control method includes: Determining the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target connecting rod; According to the corresponding relationship, an initial change trend of the angular velocity of the target connecting rod when the linear actuator moves at a constant speed is obtained; The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

2. The control method of the multi-link mechanism according to claim 1, characterized in that: The control method further comprises: The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than a preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

3. The control method of the multi-link mechanism according to claim 1, characterized in that: The angular velocity of the target link is obtained based on a derivative calculation of the pitch angle of the target link.

4. The control method of the multi-link mechanism according to claim 1, characterized in that: The step of adjusting the moving speed of the linear actuator according to the initial change trend of the angular velocity so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend comprises: Dividing the moving stroke of the linear actuator into a plurality of sub-strokes; Obtaining each initial change trend of the angular velocity of the target connecting rod in each sub-stroke; The moving speed of the linear actuator in each sub-stroke is adjusted according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

5. The control method of the multi-link mechanism according to claim 2, characterized in that: The control method further comprises: Obtaining the maximum angular velocity and the root mean square angular velocity of the target connecting rod; The angular velocity change rate of the target connecting rod is calculated according to the maximum angular velocity and the root mean square of the angular velocity.

6. The control method of the multi-link mechanism according to claim 1, characterized in that: The multi-link mechanism is a four-link mechanism, which includes a first link, a second link, a third link and a fourth link, the second link is the target link, and the first link, the second link, the third link, the fourth link and the linear actuator are connected to each other in sequence.

7. The control method of the multi-link mechanism according to claim 6, characterized in that: Both end points of the second connecting rod are not fixed, and one end point of the first connecting rod, the third connecting rod and the fourth connecting rod are fixed and the other end point is not fixed.

8. A control system for a multi-link mechanism, characterized in that: The multi-link mechanism includes a plurality of interconnected links and a linear actuator for driving the links to move. The control system includes: A first determination module is used to determine the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target connecting rod; A second determination module is used to obtain, according to the corresponding relationship, an initial change trend of the angular velocity of the target connecting rod when the linear actuator moves at a constant speed; The adjustment module is used to adjust the moving speed of the linear actuator according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and used to run on the processor, characterized in that: When the processor executes the computer program, the control method of the multi-link mechanism according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the control method of the multi-link mechanism according to any one of claims 1 to 7 is implemented.

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