Multi-degree-of-freedom floating machining method and multi-degree-of-freedom floating machining system

Abstract

The invention relates to the technical field of machining and manufacturing, and provides a multi-degree-of-freedom floating machining method and a multi-degree-of-freedom floating machining system.In the method, the real-time position of a multi-degree-of-freedom floating machining tool is accurately adjusted by calculating position deviation, so that the multi-degree-of-freedom floating machining tool can be tightly attached to the surface of a workpiece and uniformly apply contact force, and the machining precision is improved; damage to the to-be-machined workpiece is prevented, and workpiece surface scratching, excessive material removal or to-be-machined workpiece deformation caused by local overlarge pressure are avoided. The surface of a workpiece is smoother, roughness changes are reduced, the machining quality is improved, the abrasion rate of the multi-freedom-degree floating machining tool can be reduced, and the service life of the multi-freedom-degree floating machining tool is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of processing and manufacturing, and in particular to a multi-degree-of-freedom floating processing method and a multi-degree-of-freedom floating processing system. Background Art

[0002] Existing grinding processing technology is usually implemented using rigid tools and passive floating tools. The tool head of the rigid tool contacts the workpiece surface with a fixed force or position, while the passive floating tool achieves partial floating through mechanical springs or soft materials to alleviate the problem of uneven force.

[0003] However, when the workpiece surface is complex, the rigid tool cannot adjust in real time with the shape, which will lead to uneven contact force distribution, easily damaging the workpiece and the rigid tool. Passive floating tools lack real-time control, force adjustment is not flexible, and the effect is limited when facing large surface changes. Summary of the invention

[0004] The invention provides a multi-degree-of-freedom floating machining method and a multi-degree-of-freedom floating machining system, which are used to solve the defects in the prior art.

[0005] The present invention provides a multi-degree-of-freedom floating processing method, comprising: Collecting the real-time contact force of the multi-degree-of-freedom floating machining tool on the workpiece surface and the real-time position of the multi-degree-of-freedom floating machining tool during machining; Calculating a contact force deviation based on the real-time contact force and the target contact force, and calculating a position deviation based on the contact force deviation by applying an impedance model of the multi-degree-of-freedom floating machining tool on the workpiece surface; If the position deviation is greater than or equal to the preset deviation, the real-time position is adjusted based on the position deviation, and the model parameters of the impedance model are adjusted when at least one of the real-time contact force, the surface characteristics of the workpiece surface, and the state of the multi-degree-of-freedom floating machining tool changes.

[0006] According to a multi-degree-of-freedom floating machining method provided by the present invention, the model parameters include damping and stiffness; When the real-time contact force changes, adjusting the model parameters of the impedance model includes: if the real-time contact force increases, increasing the damping or reducing the stiffness; When the surface characteristics of the workpiece surface change, adjusting the model parameters of the impedance model includes: if the hardness of the workpiece surface increases, increasing the stiffness; if the hardness of the workpiece surface decreases, reducing the stiffness; When the state of the multi-degree-of-freedom floating processing tool changes, the model parameters of the impedance model are adjusted, including: if the multi-degree-of-freedom floating processing tool vibrates or jumps, the damping is increased; if the response speed of the multi-degree-of-freedom floating processing tool is less than or equal to a first preset speed, the damping is reduced.

[0007] According to a multi-degree-of-freedom floating machining method provided by the present invention, the model parameters include damping, stiffness and inertia; and adjusting the real-time position based on the position deviation includes: During the process of adjusting the real-time position, if the real-time contact force is greater than the maximum tolerance, the moving speed of the multi-degree-of-freedom floating machining tool is controlled to be greater than or equal to a second preset speed, and at least one of reducing the damping, lowering the stiffness, and increasing the inertia is performed to stop the machining process.

[0008] According to a multi-degree-of-freedom floating machining method provided by the present invention, the model parameters include multiple ones, and the initial values ​​of the model parameters are determined based on the following steps: Determining historical processing information; the historical processing information includes surface characteristics of historically processed workpieces, contact force deviations during processing, and processing effects; Counting the mean and variance of the contact force deviation under different value combinations of the model parameters, and determining a first optimal value combination of the model parameters based on the mean and variance; Analyzing the correlation between the processing effect and the different value combinations, and determining the most relevant value combination for the processing effect based on the correlation; Based on the surface characteristics of the historically processed workpieces, determining different categories of the historically processed workpieces, and determining second optimal value combinations of the different categories of historically processed workpieces; Based on the surface characteristics of the historically processed workpiece, a neural network is applied to predict a third optimal value combination; The initial value is determined based on the first optimal value combination, the most relevant value combination, the second optimal value combination, and the third optimal value combination.

[0009] According to a multi-degree-of-freedom floating machining method provided by the present invention, the model parameters include stiffness; The step of calculating the position deviation based on the contact force deviation and applying the impedance model of the multi-degree-of-freedom floating machining tool on the workpiece surface comprises: Based on the contact force deviation, the stiffness is applied and the position deviation is calculated.

[0010] The present invention also provides a multi-degree-of-freedom floating processing system, comprising: a multi-degree-of-freedom floating processing tool, a host and a controller, wherein the controller is communicatively connected to the multi-degree-of-freedom floating processing tool, and the host is communicatively connected to the controller; The host is used to execute the above-mentioned multi-degree-of-freedom floating machining method, and generate a position adjustment instruction based on the position deviation, generate a parameter adjustment instruction when at least one of the real-time contact force, the surface characteristics of the workpiece surface, and the state of the multi-degree-of-freedom floating machining tool changes, and send the position adjustment instruction and the parameter adjustment instruction to the controller; The controller is used to receive the position adjustment instruction and the parameter adjustment instruction, and adjust the real-time position based on the position adjustment instruction, and adjust the model parameter based on the parameter adjustment instruction.

[0011] According to a multi-degree-of-freedom floating machining system provided by the present invention, a force sensor and a position sensor are arranged on the multi-degree-of-freedom floating machining tool; The force sensor and the position sensor are respectively connected to the host; The force sensor is used to collect the real-time contact force and send the real-time contact force to the host; The position sensor is used to collect the real-time position and send the real-time position to the host.

[0012] According to a multi-degree-of-freedom floating machining system provided by the present invention, the multi-degree-of-freedom floating machining tool comprises: a first flange, a second flange and a plurality of pneumatic muscles, wherein the plurality of pneumatic muscles are communicatively connected with the controller; One end of each of the plurality of pneumatic muscles is hinged to the first flange, and the other end of each of the plurality of pneumatic muscles is hinged to the second flange.

[0013] According to a multi-degree-of-freedom floating machining system provided by the present invention, the multi-degree-of-freedom floating machining tool further includes a linear drive member; The driving end of the linear drive member is connected to the first flange, and the controller is in communication connection with the linear drive member; The controller is specifically used to control the extension and retraction of the linear drive member based on the position adjustment instruction to adjust the real-time position.

[0014] According to a multi-degree-of-freedom floating machining system provided by the present invention, the multi-degree-of-freedom floating machining tool further comprises a plurality of linear modules; The multiple linear modules are fixedly installed on the side of the second flange facing the first flange. The multiple linear modules are arranged in a one-to-one correspondence with the multiple pneumatic muscles. Each pneumatic muscle is hinged to the slide of the corresponding linear module.

[0015] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the multi-degree-of-freedom floating machining method as described above is implemented.

[0016] The present invention also provides a non-transitory computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the multi-degree-of-freedom floating processing method as described above is implemented.

[0017] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the multi-degree-of-freedom floating machining method as described above is implemented.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The multi-degree-of-freedom floating processing method and multi-degree-of-freedom floating processing system provided by the present invention first collect the real-time contact force of the multi-degree-of-freedom floating processing tool on the workpiece surface and the real-time position of the multi-degree-of-freedom floating processing tool during the processing process; then use the real-time contact force and the target contact force to calculate the contact force deviation, and use the contact force deviation to apply the impedance model of the multi-degree-of-freedom floating processing tool on the workpiece surface to calculate the position deviation; finally use the position deviation to adjust the real-time position, and adjust the model parameters of the impedance model when at least one of the real-time contact force, the surface characteristics of the workpiece surface and the state of the multi-degree-of-freedom floating processing tool changes. In this method, the calculated position deviation is used to accurately adjust the real-time position of the multi-degree-of-freedom floating processing tool, so that the multi-degree-of-freedom floating processing tool can be close to the workpiece surface and evenly apply the contact force, prevent damage to the workpiece to be processed, and avoid local excessive pressure causing scratches on the workpiece surface, excessive material removal or deformation of the workpiece to be processed. Not only can the workpiece surface be smoother, the roughness change is reduced, and the processing quality is improved, but also the wear rate of the multi-degree-of-freedom floating processing tool can be reduced, and the service life of the multi-degree-of-freedom floating processing tool can be extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on the drawings in the following description without paying any creative work.

[0020] Figure 1 It is a schematic flow chart of the multi-degree-of-freedom floating processing method provided by the present invention; Figure 2 It is a structural schematic diagram of a multi-degree-of-freedom floating machining system provided by the present invention; Figure 3It is a structural schematic diagram of a multi-degree-of-freedom floating processing tool provided by the present invention; Figure 4 is a schematic diagram of the structure of an electronic device provided by the present invention; In the figure: 1. First flange; 2. Second flange; 3. Pneumatic muscle; 4. Linear drive; 5. Connecting flange; 6. Ball screw; 7. Ball cage universal joint; 8. Distance sensor; 9. Linear module; 10. First support; 11. Second support; 12. Force sensor; 13. Position sensor. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] Figure 1 FIG. 1 is a flow chart of a multi-degree-of-freedom floating processing method provided in an embodiment of the present invention, such as Figure 1 As shown, the method includes: S1, collecting the real-time contact force of the multi-degree-of-freedom floating machining tool on the workpiece surface and the real-time position of the multi-degree-of-freedom floating machining tool during machining; S2, calculating a contact force deviation based on the real-time contact force and the target contact force, and calculating a position deviation based on the contact force deviation by applying an impedance model of the multi-degree-of-freedom floating machining tool on the workpiece surface; S3, if the position deviation is greater than or equal to the preset deviation, adjust the real-time position based on the position deviation, and adjust the model parameters of the impedance model when at least one of the real-time contact force, the surface characteristics of the workpiece surface, and the state of the multi-degree-of-freedom floating machining tool changes.

[0023] Specifically, the multi-degree-of-freedom floating processing method provided in the embodiment of the present invention is executed by a multi-degree-of-freedom floating processing device, which can be configured in a host of a multi-degree-of-freedom floating processing system. The host can be a computer, which can be a local computer or a cloud computer. The local computer can be a computer, a tablet, etc., which is not specifically limited here.

[0024] First, step S1 is performed to collect the real-time contact force of the multi-degree-of-freedom floating machining tool on the workpiece surface during the machining process. The machining process is the machining process of the multi-degree-of-freedom floating machining tool on the workpiece to be machined. The multi-degree-of-freedom floating machining tool can be a floating machining tool with three degrees of freedom or six degrees of freedom. The workpiece surface is the surface that needs to be machined for the workpiece to be machined, which can be a complex surface or a regular surface, and is not specifically limited here.

[0025] The real-time contact force is the grinding force of the multi-degree-of-freedom floating processing tool on the workpiece surface, which can be collected by a force sensor arranged on the multi-degree-of-freedom floating processing tool, and the force sensor can send the collected real-time contact force to the host. The real-time position can be collected by a position sensor arranged on the multi-degree-of-freedom floating processing tool, and the position sensor can send the collected real-time position to the host.

[0026] It is understandable that the position sensor may be a posture sensor that can synchronously collect position and posture, such as an inertial measurement unit (IMU) posture sensor, or a conventional position sensor that only has a position collection function, which is not specifically limited here.

[0027] Then, step S2 is performed to calculate the contact force deviation using the real-time contact force and the target contact force. The target contact force can be set according to the processing requirements of the workpiece surface, which is not specifically limited here. For example, the target contact force can be set to 5N or other values.

[0028] Here, the difference between the target contact force and the real-time contact force can be directly used as the contact force deviation. If the target contact force is 5N and the real-time contact force at a certain moment is 6N, the contact force deviation is -1N. That is, F_error = F_target - F_actual = -1; Among them, F_error is the contact force deviation, F_target is the target contact force, and F_actual is the real-time contact force.

[0029] Then, the contact force deviation can be used to apply the impedance model of the multi-degree-of-freedom floating processing tool on the workpiece surface to calculate the position deviation. It can be understood that the impedance model refers to the response characteristics of the multi-degree-of-freedom floating processing tool when it contacts the workpiece surface, and the model parameters of the impedance model may include stiffness K, damping B and inertia M. The model parameters of the impedance model can be used to control the flexible response of the multi-degree-of-freedom floating processing tool. For example, the stiffness K can control the hardness of the multi-degree-of-freedom floating processing tool when it contacts the workpiece surface. A lower stiffness can be set for softer workpiece surfaces to avoid excessive grinding. Damping B can control the smoothness of the movement of the multi-degree-of-freedom floating processing tool to prevent the multi-degree-of-freedom floating processing tool from jumping or vibrating on the surface.

[0030] In the embodiment of the present invention, the initial values ​​of the model parameters of the impedance model may be set to: K=100N / m, B=10Ns / m, M=1kg.

[0031] When calculating the position deviation, the contact force deviation can be used to apply the stiffness K to calculate the position deviation. For example, the ratio of the contact force deviation to the stiffness K can be used as the position deviation, that is, △x=F_error / K; where △x is the position deviation. If the stiffness K=100N / m, the position deviation is △x=-1 / 100=-0.01, in units of m.

[0032] Finally, step S3 is executed. When the position deviation is greater than or equal to the preset deviation, the real-time position of the multi-degree-of-freedom floating processing tool can be adjusted by using the position deviation, that is, by adjusting the real-time position of the multi-degree-of-freedom floating processing tool, the position deviation is reduced to a minimum or 0, the contact force deviation is reduced to a minimum or 0, and the real-time contact force is close to or equal to the target contact force. Here, the preset deviation can be set as needed.

[0033] For example, if the position deviation is △x=-0.01m, the multi-degree-of-freedom floating machining tool can be moved 0.01m away from the workpiece surface to reduce the real-time contact force.

[0034] At the same time, it is determined whether the real-time contact force, the surface characteristics of the workpiece surface and the state of the multi-degree-of-freedom floating processing tool have changed. If at least one of the real-time contact force, the surface characteristics of the workpiece surface and the state of the multi-degree-of-freedom floating processing tool has changed, the model parameters of the impedance model can be adjusted to enable the multi-degree-of-freedom floating processing tool to achieve stable contact on the workpiece surface, thereby ensuring that the multi-degree-of-freedom floating processing tool can adapt to surface changes and control the real-time contact force to achieve flexible processing within a safe range.

[0035] Here, the surface characteristics of the workpiece surface may include surface hardness, surface shape, and surface roughness, etc. The state of the multi-degree-of-freedom floating processing tool may include the motion state and response state of the multi-degree-of-freedom floating processing tool. The motion state may include whether the multi-degree-of-freedom floating processing tool vibrates or jumps, and the response state may include the response speed.

[0036] When the position deviation is less than the preset deviation, the real-time contact force can be controlled according to the contact force deviation to stabilize the contact force deviation, and the multi-degree-of-freedom floating machining tool can float and maintain stable contact with the workpiece surface without changing the machining trajectory.

[0037] The multi-degree-of-freedom floating processing method provided in the embodiment of the present invention first collects the real-time contact force of the multi-degree-of-freedom floating processing tool on the workpiece surface and the real-time position of the multi-degree-of-freedom floating processing tool during the processing; then uses the real-time contact force and the target contact force to calculate the contact force deviation, and uses the contact force deviation to apply the impedance model of the multi-degree-of-freedom floating processing tool on the workpiece surface to calculate the position deviation; finally uses the position deviation to adjust the real-time position, and adjusts the model parameters of the impedance model when at least one of the real-time contact force, the surface characteristics of the workpiece surface, and the state of the multi-degree-of-freedom floating processing tool changes. In this method, the calculated position deviation is used to accurately adjust the real-time position of the multi-degree-of-freedom floating processing tool, so that the multi-degree-of-freedom floating processing tool can be close to the workpiece surface and evenly apply the contact force, prevent damage to the workpiece to be processed, and avoid local excessive pressure causing scratches on the workpiece surface, excessive material removal, or deformation of the workpiece to be processed. Not only can the workpiece surface be smoother, the roughness change is reduced, and the processing quality is improved, but also the wear rate of the multi-degree-of-freedom floating processing tool can be reduced, and the service life of the multi-degree-of-freedom floating processing tool can be extended.

[0038] Based on the above embodiment, the model parameters include damping and stiffness; When the real-time contact force changes, adjusting the model parameters of the impedance model includes: if the real-time contact force increases, increasing the damping or reducing the stiffness; When the surface characteristics of the workpiece surface change, adjusting the model parameters of the impedance model includes: if the hardness of the workpiece surface increases, increasing the stiffness; if the hardness of the workpiece surface decreases, reducing the stiffness; When the state of the multi-degree-of-freedom floating processing tool changes, the model parameters of the impedance model are adjusted, including: if the multi-degree-of-freedom floating processing tool vibrates or jumps, the damping is increased; if the response speed of the multi-degree-of-freedom floating processing tool is less than or equal to a first preset speed, the damping is reduced.

[0039] Specifically, the model parameters may include at least damping and stiffness, so when the real-time contact force changes, the process of adjusting the model parameters of the impedance model may include: when the real-time contact force increases, the damping may be increased or the stiffness may be slightly reduced, for example, the amplitude of the reduction of the stiffness is less than or equal to a preset amplitude, and the preset amplitude may be set as needed and is not specifically limited here. In this way, the multi-degree-of-freedom floating machining tool responds more gently to the change of the real-time contact force, avoiding excessive pressure on the workpiece surface.

[0040] When the multi-degree-of-freedom floating machining tool moves to different areas of the workpiece surface, changes in surface characteristics may cause contact force deviation. Therefore, when the surface characteristics of the workpiece surface change, the process of adjusting the model parameters of the impedance model may include: when the hardness of the workpiece surface increases, the stiffness may be increased to ensure stable contact between the multi-degree-of-freedom floating machining tool and the workpiece surface; when the hardness of the workpiece surface decreases, the stiffness may be reduced to prevent excessive real-time contact force from causing damage to the workpiece surface.

[0041] When the state of the multi-degree-of-freedom floating processing tool changes, the process of adjusting the model parameters of the impedance model may include: when the multi-degree-of-freedom floating processing tool vibrates or jumps, damping may be increased to enhance the motion stability of the multi-degree-of-freedom floating processing tool by increasing damping; when the response speed of the multi-degree-of-freedom floating processing tool is less than or equal to the first preset speed, that is, the response of the multi-degree-of-freedom floating processing tool is too slow, damping may be reduced to improve the sensitivity of the multi-degree-of-freedom floating processing tool. Here, the first preset speed may be set as needed and is not specifically limited here.

[0042] Based on the above embodiment, the model parameters may include damping, stiffness and inertia, and then in the process of adjusting the real-time position, the magnitude relationship between the real-time contact force and the maximum tolerance is determined. The maximum tolerance is the maximum contact force applied to the workpiece surface when the workpiece surface is safely processed, for example, it may be 8N or other values.

[0043] If the real-time contact force is greater than the maximum tolerance, the protection mechanism is triggered to control the moving speed of the multi-degree-of-freedom floating processing tool to be greater than or equal to the second preset speed, that is, the multi-degree-of-freedom floating processing tool is controlled to move rapidly to reduce the real-time contact force. During the rapid movement of the multi-degree-of-freedom floating processing tool, the model parameters of the impedance model can also be dynamically adjusted, such as reducing damping, reducing stiffness, and increasing inertia, and the processing process is stopped.

[0044] Here, by reducing the damping, the response speed of the multi-degree-of-freedom floating machining tool can be improved, and the buffering effect of the multi-degree-of-freedom floating machining tool on the surface force of the workpiece can be reduced. By appropriately reducing the stiffness, the multi-degree-of-freedom floating machining tool can be made softer and release the excess contact force faster. By increasing the inertia, more buffering stability can be provided when the real-time contact force changes suddenly. By stopping the machining process, the loss of the tool to be processed can be prevented.

[0045] Based on the above embodiment, the model parameters may include multiple parameters, that is, at least two of damping, stiffness and inertia may be included, and the initial value of the model parameter may be determined by the following steps: First, historical processing information can be determined, which can include the surface characteristics of the historically processed workpiece, the contact force deviation during the processing, and the processing effect. The historical processing tools can include multiple tools, and the multiple historical processing tools can be divided into multiple categories according to the surface characteristics. The processing effect can be information such as the surface uniformity of the processed workpiece and whether the historically processed workpiece is damaged, which can be obtained through manual annotation.

[0046] In addition, the historical processing information also includes the initial values ​​of model parameters, real-time contact force, real-time position, movement speed and movement acceleration of multi-degree-of-freedom floating processing tools, etc.

[0047] Afterwards, the historical processing information can also be cleaned up, that is, outliers in the historical processing information can be removed, such as mutation data caused by equipment failure or external interference.

[0048] After that, you can also establish a database (such as a CSV file, SQL database, etc.) to organize the historical processing information for data cleaning into a structured format for subsequent analysis.

[0049] Then, the mean and variance of the contact force deviation under different value combinations of the model parameters can be statistically calculated, and the first optimal value combination of the model parameters can be determined by calculating the mean and variance. Here, the value combination of the model parameters with the minimum mean and variance can be selected as the first optimal value combination. The contact force deviation corresponding to the first optimal value combination is the smallest, and the real-time contact force is the most stable.

[0050] The correlation between the processing effect and different value combinations is analyzed, and the most relevant value combination with the processing effect is determined by using the correlation. Here, the value combination with the highest correlation can be used as the most relevant value combination. The processing effect of the most relevant value combination is the best.

[0051] Different categories of historically processed workpieces are determined by using the surface characteristics of the historically processed workpieces, and the second optimal value combination of historically processed workpieces of each category can be selected from the value combinations corresponding to the historically processed workpieces of each category. Further, the second optimal value combinations of historically processed workpieces of different categories can be determined.

[0052] By using the surface characteristics of the historically processed workpieces, a neural network can be applied to predict the third optimal value combination. The input of the neural network can be the surface characteristics of the historically processed tools, and the output can be the third optimal value combination, which can be obtained by training the historical processing information carrying the optimal value combination label of the model parameters.

[0053] Finally, the first optimal value combination, the most relevant value combination, the second optimal value combination, and the third optimal value combination can be used to determine the initial value. That is, in different situations, different value combinations can be selected as the initial value, or one of the value combinations can be randomly selected as the initial value, which is not specifically limited here.

[0054] In the embodiment of the present invention, the initial values ​​of the model parameters are determined by using the historical processing information, so that the multi-degree-of-freedom floating processing process can be made more efficient.

[0055] Based on the above embodiments, Figure 2 As shown, an embodiment of the present invention further provides a multi-degree-of-freedom floating processing system, including: a multi-degree-of-freedom floating processing tool 21, a host 22 and a controller 23, wherein the controller 23 is connected to the multi-degree-of-freedom floating processing tool 21 for communication, and the host 22 is connected to the controller 23 for communication; The host 22 is used to execute the multi-degree-of-freedom floating machining method provided in the above embodiments, and generate a position adjustment instruction based on the position deviation, and generate a parameter adjustment instruction when at least one of the real-time contact force, the surface characteristics of the workpiece surface, and the state of the multi-degree-of-freedom floating machining tool changes, and send the position adjustment instruction and the parameter adjustment instruction to the controller; The controller 23 is used to receive the position adjustment instruction and the parameter adjustment instruction, and adjust the real-time position based on the position adjustment instruction, and adjust the model parameters based on the parameter adjustment instruction.

[0056] Specifically, in the embodiment of the present invention, the host 22 can be a computer, which can be a local computer or a cloud computer, and the local computer can be a computer, a tablet, etc., which is not specifically limited here. The host 22 can generate instructions and send the instructions to the controller 23, and control the controller 23 through the instructions, so that the controller 23 controls the multi-degree-of-freedom floating machining tool 21 according to the instructions.

[0057] The instructions generated by the host 22 may include position adjustment instructions and parameter adjustment instructions. The position adjustment instructions are used to control the controller 23 to adjust the real-time position of the multi-degree-of-freedom floating machining tool 21 , and the parameter adjustment instructions are used to control the controller 23 to adjust the model parameters.

[0058] The multi-degree-of-freedom floating processing system provided in the embodiment of the present invention comprises: a multi-degree-of-freedom floating processing tool, a host and a controller. In the system, the host executes the multi-degree-of-freedom floating processing method, and the real-time position of the multi-degree-of-freedom floating processing tool can be accurately adjusted, so that the multi-degree-of-freedom floating processing tool can be close to the surface of the workpiece and evenly apply the contact force to prevent damage to the workpiece to be processed, and avoid local excessive pressure causing scratches on the workpiece surface, excessive material removal or deformation of the workpiece to be processed. Not only can the workpiece surface be smoother, the roughness change is reduced, and the processing quality is improved, but also the wear rate of the multi-degree-of-freedom floating processing tool can be reduced, and the service life of the multi-degree-of-freedom floating processing tool can be extended.

[0059] Based on the above embodiments, Figure 3 As shown, a force sensor 12 and a position sensor 13 are provided on the multi-degree-of-freedom floating processing tool; The force sensor 12 and the position sensor 13 are respectively connected to the host 22; The force sensor 12 is used to collect the real-time contact force and send the real-time contact force to the host 22; The position sensor 13 is used to collect the real-time position and send the real-time position to the host 22 .

[0060] like Figure 3 As shown, the multi-degree-of-freedom floating machining tool may include: a first flange 1, a second flange 2 and a plurality of pneumatic muscles 3, wherein the plurality of pneumatic muscles 3 are communicatively connected with the controller 23; One ends of the multiple pneumatic muscles 3 are hinged to the first flange 1 , and the other ends are hinged to the second flange 2 .

[0061] The force sensor 12 may be disposed inside the first flange 1 .

[0062] The first flange 1 is used to install a tooling such as a grinding head. The second flange 2 is used to connect to the fuselage. The pneumatic muscles 3 can be extended and retracted. Under the control of the controller, when multiple pneumatic muscles 3 are extended and retracted synchronously, the first flange 1 can be raised and lowered together, thereby adjusting the distance between the tooling and the workpiece to be processed.

[0063] In one embodiment, the plurality of pneumatic muscles 3 are divided into two groups, and the pneumatic muscles 3 in each group are stretched and retracted synchronously, cooperating with the stretching and retracting movement of the other group of pneumatic muscles to drive the first flange 1 to tilt left and right, thereby adjusting the tilt angle of the tooling to adapt to the curved surface of the workpiece to be processed. Figure 3 As shown, there are four pneumatic muscles 3, which are divided into two groups. The controller 23 controls the pneumatic muscles 3 in the same group to move synchronously. When one group of pneumatic muscles 3 is extended, the other group of pneumatic muscles 3 is contracted or does not move. Since the opposite ends of the pneumatic muscles 3 are respectively hinged to the first flange 1 and the second flange 2, the cooperation of multiple groups of pneumatic muscles 3 can drive the first flange 1 to tilt relative to the horizontal plane, thereby realizing the left and right swing of the first flange 1.

[0064] like Figure 3 As shown, the position sensor 13 is installed on the connecting flange 5, and the controller 23 is connected to the position sensor 13 for communication to control the operation of the pneumatic muscle 3. The position sensor 13 can detect the current posture state of the connecting flange 5. Since the connecting flange 5 is arranged in parallel with the first flange 1, the posture state of the first flange 1 can be determined according to the posture state of the connecting flange 5. When the first flange 1 is adjusted to the target position, the pneumatic muscle 3 is controlled to stop running according to the information fed back by the position sensor 13.

[0065] The multi-axis floating machining tool provided by the present invention has a first flange 1 and a second flange 2 connected by a plurality of pneumatic muscles 3. The controller 23 controls the extension and contraction of each pneumatic muscle 3, thereby adjusting the swing angle and distance of the first flange 1 relative to the second flange 2, thereby being able to adapt to the machining of complex workpieces to be machined.

[0066] like Figure 3 As shown, the multi-freedom floating processing tool also includes a linear drive member 4; The driving end of the linear drive member 4 is connected to the first flange 1, and the controller 23 is in communication connection with the linear drive member 4; The controller 23 is specifically used to control the extension and retraction of the linear drive member 4 based on the position adjustment instruction to adjust the real-time position.

[0067] Specifically, Figure 3As shown, the linear drive 4 is fixed to the connecting flange 5, and the position sensor 13 can be located on the inner side of the bottom of the linear drive 4. The driving end of the linear drive 4 is connected to the first flange 1. Under the drive of the linear drive 4, the first flange 1 moves away from or close to the second flange 2. When in use, after the inclination angle of the first flange 1 is adjusted to the right position, the linear drive 4 pushes the first flange 1 up and down. At the same time, each pneumatic muscle 3 is extended or shortened to ensure that the first flange 1 is translated up and down to adjust the real-time contact force applied by the tooling to the workpiece. The force sensor 12 collects the real-time contact force between the tooling and the first flange 1, and the controller 23 controls the operation of the linear drive 4 according to the magnitude of the real-time contact force. When the controller 23 calculates the real-time contact force applied by the tooling to the workpiece based on the real-time contact force between the tooling and the first flange 1, the linear drive 4 is controlled to stop driving when the real-time contact force applied by the tooling to the workpiece reaches a preset value. When the preset value is not reached, the linear drive member 4 is controlled to continue to operate until the real-time contact force applied by the tooling device on the workpiece reaches the target contact force.

[0068] The multi-axis floating processing tool provided in an embodiment of the present invention adjusts the height of the first flange 1 by means of the extension and retraction of the linear drive member 4. The controller 23 controls the operation of the linear drive member 4 according to the detection value of the force sensor 12, thereby controlling the magnitude of the real-time contact force applied by the tooling to the processing workpiece.

[0069] Optionally, the linear drive member 4 is a cylinder, and a piston rod of the cylinder is connected to the first flange 1 .

[0070] The multi-axis floating machining tool also includes a connecting flange 5 and a ball screw 6. The connecting flange 5 is connected to the second flange 2 through a ball cage universal joint 7. The ball screw 6 is fixed to the connecting flange 5. The first flange 1 is fixedly connected to the slider of the ball screw 6.

[0071] like Figure 3 As shown, one end of the linear drive 4 is fixed to the connecting flange 5, and the other end is fixedly connected to the first flange 1. When the first flange 1 tilts relative to the second flange 2 as the pneumatic muscle 3 expands and contracts, the connecting flange 5 adaptively adjusts its direction with the help of the ball cage universal joint 7, so that the first flange 1 and the connecting flange 5 are always in a parallel state. Under the action of the linear drive 4, the distance between the connecting flange 5 and the first flange 1 can change. The ball screw 6 is fixed to the connecting flange 5, and the first flange 1 is installed on the slider of the ball screw 6. When the linear drive 4 drives the first flange 1 to rise and fall, the ball screw 6 moves synchronously to improve the stability of the first flange 1.

[0072] Specifically, Figure 3As shown, the connecting flange 5 is provided with a connecting rod, the ball shell of the ball cage universal joint 7 is fixed to the second flange 2, and the star sleeve of the ball cage universal joint 7 is fixedly connected to the end of the connecting rod. The inclination angle of the first flange 1 is adjusted by the rotational cooperation between the star sleeve and the ball shell.

[0073] like Figure 3 As shown, a distance sensor 8 is also installed on the connecting flange 5 . The distance sensor 8 is used to detect the distance between the connecting flange 5 and the first flange 1 . The controller 23 is in communication connection with the distance sensor 8 .

[0074] The distance sensor 8 is an infrared sensor, an ultrasonic sensor, a laser sensor or a radar sensor, and the controller 23 determines the distance between the connecting flange 5 and the first flange 1 according to the detection information of the distance sensor 8. After the distance between the connecting flange 5 and the first flange 1 reaches the preset distance, the controller 23 controls the linear drive 4 and the ball screw 6 to stop running. When the distance between the connecting flange 5 and the first flange 1 does not reach the preset distance, the linear drive 4 and the ball screw 6 run to adjust the distance between the connecting flange 5 and the first flange 1 until it reaches the preset distance.

[0075] like Figure 3 As shown, the first support 10 is fixedly installed on the first flange 1, and the second support 11 is fixedly installed on the second flange 2. The pneumatic tendon 3, the first support 10 and the second support 11 are arranged in a one-to-one correspondence. One end of each pneumatic tendon 3 is connected to the first flange 1 through a first support 10, and the other end of the pneumatic tendon 3 is connected to the second flange 2 through a second support 11.

[0076] Based on the above embodiment, the multi-degree-of-freedom floating processing tool further includes a plurality of linear modules; The multiple linear modules are fixedly installed on the side of the second flange facing the first flange. The multiple linear modules are arranged in a one-to-one correspondence with the multiple pneumatic muscles. Each pneumatic muscle is hinged to the slide of the corresponding linear module.

[0077] Specifically, Figure 3 As shown, the linear module 9 extends along the radial direction of the second flange 2 . Figure 3 There are four pneumatic muscles 3, and the second flange 2 is provided with four linear modules 9, each of which is connected to one of the linear modules 9. When the linear modules 9 move synchronously, driving the pneumatic muscles 3 to open outward or close inward, the distance between the first flange 1 and the second flange 2 can be adjusted even if the pneumatic muscles 3 are not moving. When the four linear modules 9 have different running strokes, the first flange 1 can be tilted relative to the second flange 2.

[0078] The multi-axis floating processing tool provided by the present invention can enhance the installation strength of the pneumatic muscle 3 and increase the height adjustment range of the first flange 1 by adding a linear module 9, so that the operating range of the first flange 1 is larger and the adjustment is more flexible.

[0079] Specifically, each of the first support 10 and the second support 11 has two oppositely disposed support ears, and the end of the pneumatic muscle 3 is accommodated between the two support ears and is rotatably connected to the support ears via a pin shaft.

[0080] like Figure 3 As shown, the first support 10 is fixed to the side of the first flange 1 facing the second flange 2, and the second support 11 is fixed to the slide of the linear module 9. The first support 10 and the second support 11 have the same structure, both including two oppositely arranged ears, and the opposite ends of the pneumatic tendon 3 are flat ears, so that the end of the pneumatic tendon 3 can be clamped between the two ears and can rotate relative to the two ears. The pin connects the ears and the ends of the pneumatic tendon 3 and can also serve as a rotating shaft.

[0081] Figure 4 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 4 As shown, the electronic device may include: a processor (Processor) 410, a communication interface (Communications Interface) 420, a memory (Memory) 430 and a communication bus 440, wherein the processor 410, the communication interface 420, and the memory 430 communicate with each other through the communication bus 440. The processor 410 may call the logic instructions in the memory 430 to execute the multi-degree-of-freedom floating processing method provided in the above embodiments.

[0082] In addition, the logic instructions in the above-mentioned memory 430 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0083] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the multi-degree-of-freedom floating processing method provided in the above embodiments.

[0084] On the other hand, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the computer program is executed by a processor to execute the multi-degree-of-freedom floating machining method provided in the above embodiments.

[0085] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0086] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-degree-of-freedom floating processing method, characterized in that: include: Collecting the real-time contact force of the multi-degree-of-freedom floating machining tool on the workpiece surface and the real-time position of the multi-degree-of-freedom floating machining tool during machining; Based on the real-time contact force and the target contact force, a contact force deviation is calculated, and based on the contact force deviation, an impedance model of the multi-degree-of-freedom floating machining tool on the workpiece surface is applied to calculate a position deviation; the impedance model refers to a response characteristic of the multi-degree-of-freedom floating machining tool when it contacts the workpiece surface; If the position deviation is greater than or equal to a preset deviation, adjusting the real-time position based on the position deviation, and adjusting the model parameters of the impedance model when at least one of the real-time contact force, the surface property of the workpiece surface, and the state of the multi-degree-of-freedom floating machining tool changes; The model parameters include damping and stiffness; When the real-time contact force changes, adjusting the model parameters of the impedance model includes: if the real-time contact force increases, increasing the damping or reducing the stiffness; When the surface characteristics of the workpiece surface change, adjusting the model parameters of the impedance model includes: if the hardness of the workpiece surface increases, increasing the stiffness; if the hardness of the workpiece surface decreases, reducing the stiffness; When the state of the multi-degree-of-freedom floating processing tool changes, the model parameters of the impedance model are adjusted, including: if the multi-degree-of-freedom floating processing tool vibrates or jumps, the damping is increased; if the response speed of the multi-degree-of-freedom floating processing tool is less than or equal to a first preset speed, the damping is reduced.

2. The multi-degree-of-freedom floating machining method according to claim 1, characterized in that: The model parameters also include inertia; and adjusting the real-time position based on the position deviation includes: During the process of adjusting the real-time position, if the real-time contact force is greater than the maximum tolerance, the moving speed of the multi-degree-of-freedom floating machining tool is controlled to be greater than or equal to a second preset speed, and at least one of reducing the damping, lowering the stiffness, and increasing the inertia is performed to stop the machining process.

3. The multi-degree-of-freedom floating machining method according to any one of claims 1-2, characterized in that: The model parameters include multiple ones, and the initial values ​​of the model parameters are determined based on the following steps: Determining historical processing information; the historical processing information includes surface characteristics of historically processed workpieces, contact force deviations during processing, and processing effects; Counting the mean and variance of the contact force deviation under different value combinations of the model parameters, and determining a first optimal value combination of the model parameters based on the mean and variance; Analyzing the correlation between the processing effect and the different value combinations, and determining the most relevant value combination for the processing effect based on the correlation; Based on the surface characteristics of the historically processed workpieces, determining different categories of the historically processed workpieces, and determining second optimal value combinations of the different categories of historically processed workpieces; Based on the surface characteristics of the historically processed workpiece, a neural network is applied to predict a third optimal value combination; The initial value is determined based on the first optimal value combination, the most relevant value combination, the second optimal value combination, and the third optimal value combination.

4. The multi-degree-of-freedom floating machining method according to any one of claims 1-2, characterized in that: The model parameters include stiffness; The step of calculating the position deviation based on the contact force deviation and applying the impedance model of the multi-degree-of-freedom floating machining tool on the workpiece surface comprises: Based on the contact force deviation, the stiffness is applied and the position deviation is calculated.

5. A multi-degree-of-freedom floating processing system, characterized in that: include: A multi-degree-of-freedom floating processing tool, a host and a controller, wherein the controller is communicatively connected to the multi-degree-of-freedom floating processing tool, and the host is communicatively connected to the controller; The host is used to execute the multi-degree-of-freedom floating machining method according to any one of claims 1 to 4, and generate a position adjustment instruction based on the position deviation, generate a parameter adjustment instruction when at least one of the real-time contact force, the surface characteristics of the workpiece surface, and the state of the multi-degree-of-freedom floating machining tool changes, and send the position adjustment instruction and the parameter adjustment instruction to the controller; The controller is used to receive the position adjustment instruction and the parameter adjustment instruction, and adjust the real-time position based on the position adjustment instruction, and adjust the model parameter based on the parameter adjustment instruction.

6. The multi-degree-of-freedom floating machining system according to claim 5, characterized in that: A force sensor and a position sensor are arranged on the multi-degree-of-freedom floating processing tool; The force sensor and the position sensor are respectively connected to the host; The force sensor is used to collect the real-time contact force and send the real-time contact force to the host; The position sensor is used to collect the real-time position and send the real-time position to the host.

7. The multi-degree-of-freedom floating machining system according to claim 5, characterized in that: The multi-degree-of-freedom floating machining tool comprises: a first flange, a second flange and a plurality of pneumatic muscles, wherein the plurality of pneumatic muscles are communicatively connected with the controller; One end of each of the plurality of pneumatic muscles is hinged to the first flange, and the other end of each of the plurality of pneumatic muscles is hinged to the second flange.

8. The multi-degree-of-freedom floating machining system according to claim 7, characterized in that: The multi-freedom floating processing tool also includes a linear drive member; The driving end of the linear drive member is connected to the first flange, and the controller is in communication connection with the linear drive member; The controller is specifically used to control the extension and retraction of the linear drive member based on the position adjustment instruction to adjust the real-time position.

9. The multi-degree-of-freedom floating machining system according to claim 7, characterized in that: The multi-freedom floating processing tool also includes a plurality of linear modules; The multiple linear modules are fixedly installed on the side of the second flange facing the first flange. The multiple linear modules are arranged in a one-to-one correspondence with the multiple pneumatic muscles. Each pneumatic muscle is hinged to the slide of the corresponding linear module.

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