Hydraulic manipulator remote operation master-slave heterogeneous matching method based on special-shaped workspace

Abstract

The application discloses a hydraulic mechanical arm remote operation master-slave heterogeneous matching method based on a special-shaped working space. The method comprises the following steps: in the case that the degrees of freedom between the slave end hydraulic mechanical arm and the master end device are inconsistent, a special-shaped working space is established; the dimensions between the slave end hydraulic mechanical arm and the master end device are matched by using a remote operation instruction adaptive mapping method, and finally the hydraulic mechanical arm remote operation master-slave heterogeneous matching is realized. The method realizes the consistency integration of the master-slave working space dimensions, solves the problem that the inconsistency of the master-slave working space dimensions caused by the different degrees of freedom between the slave end hydraulic mechanical arm and the master end device affects the accurate reproduction of the actual operation instruction at the slave end, realizes the full use of the slave end working space and guarantees the accurate reproduction of the hydraulic mechanical arm remote operation instruction in the actual operation process, and finally significantly improves the remote operation effect of the hydraulic mechanical arm under the master-slave heterogeneous condition.

Description

Technical Field

[0001] This invention relates to a master-slave heterogeneous matching method for teleoperation of a robotic arm, specifically to a master-slave heterogeneous matching method for teleoperation of a hydraulic robotic arm based on an irregularly shaped workspace. Background Technology

[0002] Hydraulic robotic arms are typically used for demanding tasks such as heavy-duty operations. However, with industrial development and continuous advancements in human exploration, the complexity of hydraulic robotic arm tasks is constantly increasing, as are the requirements for operational precision. Meanwhile, the current control precision of hydraulic robotic arms is far from reaching the micron-level precision of industrial robotic arms, and their ability to process environmental information is weak, resulting in slow real-time response and action command generation. Therefore, under current technological conditions, fully autonomous operation of hydraulic robotic arms is difficult, and remote operation with human intervention remains the more reasonable method for robotic arm operation at present. However, one of the main problems in the current implementation of remote operation of hydraulic robotic arms is the significant difference in physical configuration between them and the general-purpose master arm on the market. The low similarity between their workspaces leads to the inability to accurately reproduce master-end operation commands, affecting the actual remote operation effect of the hydraulic robotic arm. While customizing the master arm to specifically suit the physical configuration of the hydraulic robotic arm can avoid the master-slave heterogeneity problem, it undoubtedly greatly increases operating costs. Therefore, how to solve the master-slave heterogeneity problem in the remote operation of hydraulic robotic arms to improve actual operating results while saving operating costs is an urgent problem to be solved. Summary of the Invention

[0003] To address the problems existing in the background technology, this invention provides a heterogeneous matching (TWAM) method for master-slave remote operation of hydraulic robotic arms based on heterogeneous workspaces. This invention solves the problem of poor remote operation performance of hydraulic robotic arms when the physical configurations of the master and slave ends differ significantly and the similarity of their workspaces is too low. Specifically, this invention is a heterogeneous matching method based on heterogeneous workspaces proposed for master-slave heterogeneous situations during the remote operation of hydraulic robotic arms. It can accurately reproduce actual operation commands at the slave end (operation segment) even when the configurations of the hydraulic robotic arm and the master device differ significantly, thereby ensuring that the hydraulic robotic arm can complete tasks according to the operator's instructions and improving the actual remote operation performance of the hydraulic robotic arm.

[0004] The technical solution adopted in this invention is:

[0005] The present invention provides a master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace, comprising:

[0006] The first step is to establish an irregular workspace for the slave hydraulic manipulator and the master device when the degrees of freedom are inconsistent.

[0007] The second step involves using the heterogeneous workspaces of the slave hydraulic manipulator and the master device to match the dimensions between them using a teleoperation command adaptive mapping method, ultimately achieving master-slave heterogeneous matching for teleoperation of the hydraulic manipulator.

[0008] To address the potential discrepancy in the number of degrees of freedom between the slave-end hydraulic manipulator and the master-end device, leading to a mismatch in workspace dimensions, a method for constructing a non-standard workspace is proposed to integrate the workspace dimensions of both. Based on the created non-standard workspace, a novel adaptive mapping method for teleoperation commands is proposed to fully utilize the slave-end workspace and ensure accurate reproduction of the hydraulic manipulator's teleoperation commands during actual operation.

[0009] In the first step, the inconsistency of degrees of freedom between the slave hydraulic manipulator and the master device specifically refers to the inconsistency in the number of degrees of freedom and / or rotation direction of the joints of the slave hydraulic manipulator and the master device.

[0010] When using a commercially available general-purpose master arm as the master device, the physical configurations of the master and slave hydraulic robotic arms are often different, with significant differences in the number and settings of their degrees of freedom. This results in inconsistencies in the master and slave workspace dimensions, leading to the inability to accurately reproduce master-end operation commands on the slave end. Therefore, to solve the problem of heterogeneous master-slave teleoperation of hydraulic robotic arms, it is first necessary to reintegrate the master and slave workspaces and unify their dimensions. Thus, this invention proposes a concept of "heterogeneous workspace," distinct from traditional Cartesian space, which sets up a multi-dimensional heterogeneous workspace based on the number of degrees of freedom of the slave hydraulic robotic arm.

[0011] In the first step described above, the irregularly shaped workspaces of the slave-end hydraulic robotic arm and the master-end equipment are as follows:

[0012] a) Irregular workspace at the slave end of the hydraulic robotic arm:

[0013] The dimension of the slave-end irregular workspace is set to be consistent with the number of degrees of freedom n of the slave-end hydraulic manipulator. In the six degrees of freedom in three-dimensional space, several degrees of freedom not included in the slave-end hydraulic manipulator are integrated into several degrees of freedom included in the slave-end hydraulic manipulator using the generalized Euler's law method. Finally, the workspace of the slave-end hydraulic manipulator is transformed into the slave-end irregular workspace.

[0014] b) Irregular workspace of the master device:

[0015] The dimensions of the main end irregular workspace are set to be consistent with the number of degrees of freedom n of the slave end hydraulic manipulator. In the six degrees of freedom in three-dimensional space, several degrees of freedom not included in the main end device are integrated into several degrees of freedom included in the main end device using the generalized Euler's law method, and finally the workspace of the main end device is transformed into the main end irregular workspace.

[0016] Based on the degree of freedom settings of the master and slave devices and the requirements of actual teleoperation tasks, each dimension of the irregular workspace is defined separately. Furthermore, when defining dimensions, it is necessary to integrate the motion degrees of freedom that the slave hydraulic manipulator cannot achieve with other achievable motion degrees of freedom into a single dimension of the irregular workspace, according to the generalized Euler's law. This ensures that the slave hydraulic manipulator can traverse any position in any dimension of the irregular workspace.

[0017] In the aforementioned slave-end heterogeneous workspace and master-end heterogeneous workspace, if the direction of the joint motion degree of freedom of the m-th dimension in the slave-end heterogeneous workspace and the m-th dimension in the master-end heterogeneous workspace is the same, then the m-th dimension in the slave-end heterogeneous workspace and the m-th dimension in the master-end heterogeneous workspace are isomorphic dimensions, and the remaining dimensions in the slave-end heterogeneous workspace and the master-end heterogeneous workspace are non-isomorphic dimensions.

[0018] A dimension is considered isomorphic when its index and the direction of the joint's degrees of freedom are the same.

[0019] In the second step, based on the irregular workspaces of the slave hydraulic manipulator and the master device, a teleoperation command adaptive mapping method is used to match the slave hydraulic manipulator and the master device, as follows:

[0020] 2.1) For each isomorphic dimension in the slave heteromorphic workspace and the master heteromorphic workspace, establish an isomorphic dimension position-position mapping model, input the actual operation instructions of the isomorphic dimension into the isomorphic dimension position-position mapping model, and output the isomorphic dimension instruction mapping result.

[0021] 2.2) For each non-isomorphic dimension in the slave-end heteromorphic workspace and the master-end heteromorphic workspace, establish a non-isomorphic dimension location-location mapping model, input the adaptive decision factor of the master-end device into the non-isomorphic dimension location-location mapping model, and output the non-isomorphic dimension instruction mapping result.

[0022] 2.3) Establish a teleoperation command adaptive mapping model. Input the isomorphic dimension command mapping result and the non-isomorphic dimension command mapping result into the teleoperation command adaptive mapping model. The teleoperation command adaptive mapping model outputs the final teleoperation command adaptive mapping result, which will transform the coordinates of the master device in various dimensions to the slave hydraulic manipulator, and finally realize the master-slave heterogeneous matching of the hydraulic manipulator teleoperation.

[0023] In step 2.1), the isomorphic dimension position-position mapping model is as follows:

[0024]

[0025] in, and P m These are the isomorphic dimension instruction mapping result and the isomorphic dimension actual operation instruction, respectively, and f() is the position-position mapping function.

[0026] isomorphic dimension instruction mapping results and isomorphic dimension actual operation instruction P m Specifically, these are the coordinates on the isomorphic dimensions of the slave-end heterogeneous workspace and the master-end heterogeneous workspace, respectively.

[0027] When dimension one (D1) is a "homogeneous dimension", the mapping mode of the master and slave heterogeneous workspace dimensions (D1) is defined as a proportional position-position mapping, that is:

[0028]

[0029] in, and λ represents the coordinates on dimension 1 (D1) of the heterogeneous workspace of the master and slave ends, respectively, and λ is the scaling factor.

[0030] In step 2.2), to fully traverse the slave workspace and achieve accurate teleoperation tasks, three command mapping modes are set, and command mapping on the "non-homogeneous dimension" is implemented through adaptive switching. The three command mapping modes are: navigation mapping mode, positioning mapping mode, and transition mapping mode; the homogeneous dimension position-position mapping model is as follows:

[0031]

[0032] in, This is the result of mapping non-isomorphic dimension instructions; P N P T and P P These are the navigation mapping results, transition mapping results, and positioning mapping results, respectively; R mR is the distance between the position of the endpoint of the master device in the non-isomorphic dimension of the master's heterogeneous workspace and the center point of the non-isomorphic dimension, i.e., the adaptive decision factor; N and R P These are a first mode switching distance threshold and a second mode switching distance threshold. These thresholds can be used to divide the “non-homogeneous dimension” heterogeneous workspace into three mapping regions. When the end point of the master device is located in a different mapping region in the master “non-homogeneous dimension” heterogeneous workspace, the corresponding instruction mapping mode is executed.

[0033] Considering that the operator can directly control the end point of the master device to freely reach any position within the master-side heterogeneous workspace, the distance R between the position of the end point of the master device in the master-side "non-isomorphic" heterogeneous workspace and the center point of the master-side "non-isomorphic" heterogeneous workspace is used. m It serves as an adaptive decision factor for determining the adaptive instruction mapping mode.

[0034] The navigation mapping result P N Specifically as follows:

[0035]

[0036]

[0037] in, The position of the end effector of the hydraulic robotic arm at the current moment in the non-isomorphic dimension of the irregular workspace at the end; v is the first derivative of the navigation mapping result, dt is the mapping instruction update time; max The preset maximum mapping speed is designed to ensure that the mapping instructions do not change drastically within a short period of time; vec(R m R is the adaptive decision factor. m The unit direction vector.

[0038] The navigation mapping method is similar to the common position-velocity mapping method. The direction and distance of the vector determined by the vector direction and distance determined by the direction and magnitude of the speed change of the mapping command.

[0039] The transition mapping result P T Specifically as follows:

[0040]

[0041]

[0042] Where, α T It is the transition mapping factor, which varies with the adaptive decision factor R. m It changes with the changes; and These are the reference results obtained at the current moment using navigation mapping and positioning mapping methods, respectively.

[0043] The location mapping result P P Specifically as follows:

[0044]

[0045]

[0046]

[0047]

[0048] in, These are the single-axis mapping results for the first, second, ..., i, ..., m non-isomorphic dimensions, respectively; λ VOM This is the scaling factor for a single-axis mapping. and The actual operation instructions in the non-isomorphic dimension and the focus of the heterogeneous workspace in the "non-isomorphic dimension" at the i-th non-isomorphic dimension D are respectively. ni Coordinates on the axis; To create a heterogeneous workspace with a "non-isomorphic dimension" at the i-th non-isomorphic dimension D ni Midpoint of the mapping on the axis; σ VOM Set the preset scaling factor; and The non-isomorphic dimensions of the heterogeneous workspace at the ith non-isomorphic dimension axis D are respectively... ni The maximum and minimum values ​​on.

[0049] In step 2.3), the teleoperation command adaptive mapping model is as follows:

[0050]

[0051] Among them, P map For the final adaptive mapping result of teleoperation commands, and These are the instruction mapping results for homogeneous dimensions and the adaptive instruction mapping results for non-homogeneous dimensions, respectively; O() is the sorting function according to the heterogeneous workspace dimensions.

[0052] Taking the example robotic arm as an example, its final instruction mapping result is as follows:

[0053]

[0054] in, and These are the adaptive instruction mapping results on the "non-isomorphic dimensions" D2, D3, and D4, respectively.

[0055] In the first step, considering the physical configuration differences between the hydraulic robotic arm and the master device, a heterogeneous workspace, distinct from traditional Cartesian space, is established. In the second step, the dimensions of this heterogeneous workspace are divided into "isomorphic dimensions" and "non-isomorphic dimensions," and position-to-position mapping and adaptive mapping are performed on each, ultimately yielding an adaptive command mapping result. The proposed novel teleoperation command adaptive mapping method, TWAM, based on a heterogeneous workspace, enables perfect reproduction of master-slave operation commands on the slave end in heterogeneous master-slave scenarios during hydraulic robotic arm teleoperation, thereby improving the actual completion effect of hydraulic robotic arm teleoperation tasks and enhancing the teleoperation capability of the hydraulic robotic arm.

[0056] After obtaining the final teleoperation command adaptive mapping result P map Then, the mapping result points are transformed into continuous target trajectories with time axes through path interpolation algorithm; then, the continuous target trajectory is calculated into the joint space of the hydraulic manipulator by inverse kinematics solver to obtain the joint tracking trajectory; in addition, each joint is controlled to follow the joint tracking trajectory by the nonlinear controller of the hydraulic manipulator, and finally the operation command issued by the master operator is realized and the teleoperation task is completed.

[0057] The beneficial effects of this invention are:

[0058] 1. This invention proposes a novel method for constructing irregular workspaces, which achieves consistent integration of master and slave workspace dimensions. It solves the problem that the different degrees of freedom between the slave hydraulic robotic arm and the master device lead to inconsistencies in the master and slave workspace dimensions, thus affecting the inaccurate reproduction of actual operation commands at the slave end.

[0059] 2. This invention proposes a novel adaptive mapping method for teleoperation commands based on heterogeneous workspaces, which fully utilizes the slave-end workspace and ensures accurate reproduction of teleoperation commands of the hydraulic robotic arm during actual operation, ultimately significantly improving the teleoperation effect of the hydraulic robotic arm in the case of master-slave heterogeneity. Attached Figure Description

[0060] Figure 1 This is a flowchart of the method of the present invention;

[0061] Figure 2 This is a diagram illustrating the structure and remote operation configuration of an example hydraulic robotic arm used in this invention.

[0062] Figure 3 This is a schematic diagram illustrating the example teleoperation configuration of the master and slave "non-isomorphic" heterogeneous workspaces, adaptive mapping space, and decision factors used in this invention. Figure 3 (a) is a schematic diagram of the example teleoperation configuration of the master and slave "non-isomorphic" heterogeneous workspaces used in this invention. Figure 3(b) is a schematic diagram of the example teleoperation configuration adaptive mapping space and decision factor used in this invention;

[0063] Figure 4 This is a schematic diagram of the VOM (Video Object Mapping) method for precise instruction mapping per axis according to the present invention. Figure 4 (a) is a schematic diagram of the distribution of the "non-isomorphic" irregular workspace region of the example robotic arm on the D2 axis. Figure 4 (b) is a schematic diagram of the distribution of the "non-isomorphic" irregular workspace of the example robotic arm on the D2-D4 plane. Figure 4 (c) is the heterogeneous workspace of the "non-isomorphic dimension" from the end through the straight line. and the cross-sectional region parallel to the D2-D3 base plane and the straight line A diagram illustrating the case with only two intersection points. Figure 4 (d) is the heterogeneous workspace of the "non-isomorphic dimension" from the end through the straight line. and the cross-sectional region parallel to the D2-D3 base plane and the straight line A diagram illustrating a case where there are more than two intersection points;

[0064] Figure 5 This is a comparison chart of the command mapping results of the proposed method and the traditional command mapping method in the "non-isomorphic" heterogeneous workspace of the example hydraulic robotic arm platform. Figure 5 (a) is the mapping result obtained by the method proposed in this patent. Figure 5 (b) is the mapping result obtained by the traditional position-to-position mapping method;

[0065] Figure 6 This is an actual effect diagram of the method proposed in this invention realizing the remote operation of a hydraulic robotic arm to perform a specific grasping task on an example hydraulic robotic arm platform;

[0066] Figure 7 This is a diagram showing the instruction mapping results of the method proposed in this invention for remotely operating a specific grasping task on an example hydraulic robotic arm platform. Figure 7 (a) is the operation instruction sent in real time by the master operator. Figure 7 (b) is the real-time mapping instruction result obtained by the mapping method designed in this patent. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0068] likeFigure 1 As shown, the master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace according to the present invention includes:

[0069] The first step is to establish an irregular workspace for the slave hydraulic manipulator and the master device when the degrees of freedom are inconsistent.

[0070] In the first step, the inconsistency of degrees of freedom between the slave hydraulic manipulator and the master device specifically refers to the inconsistency in the number of degrees of freedom and / or rotation direction of the joints of the slave hydraulic manipulator and the master device.

[0071] When using a commercially available general-purpose master arm as the master device, the physical configurations of the master and slave hydraulic robotic arms are often different, with significant differences in the number and settings of their degrees of freedom. This results in inconsistencies in the master and slave workspace dimensions, leading to the inability to accurately reproduce master-end operation commands on the slave end. Therefore, to solve the problem of heterogeneous master-slave teleoperation of hydraulic robotic arms, it is first necessary to reintegrate the master and slave workspaces and unify their dimensions. Thus, this invention proposes a concept of "heterogeneous workspace," distinct from traditional Cartesian space, which sets up a multi-dimensional heterogeneous workspace based on the number of degrees of freedom of the slave hydraulic robotic arm.

[0072] In the first step, the irregularly shaped workspaces of the slave-end hydraulic robotic arm and the master-end equipment are as follows:

[0073] a) Irregular workspace at the slave end of the hydraulic robotic arm:

[0074] The dimension of the slave-end irregular workspace is set to be consistent with the number of degrees of freedom n of the slave-end hydraulic manipulator. In the six degrees of freedom in three-dimensional space, several degrees of freedom not included in the slave-end hydraulic manipulator are integrated into several degrees of freedom included in the slave-end hydraulic manipulator using the generalized Euler's law method. Finally, the workspace of the slave-end hydraulic manipulator is transformed into the slave-end irregular workspace.

[0075] b) Irregular workspace of the master device:

[0076] The dimensions of the main end irregular workspace are set to be consistent with the number of degrees of freedom n of the slave end hydraulic manipulator. In the six degrees of freedom in three-dimensional space, several degrees of freedom not included in the main end device are integrated into several degrees of freedom included in the main end device using the generalized Euler's law method, and finally the workspace of the main end device is transformed into the main end irregular workspace.

[0077] Based on the degree of freedom settings of the master and slave devices and the requirements of actual teleoperation tasks, each dimension of the irregular workspace is defined separately. Furthermore, when defining dimensions, it is necessary to integrate the motion degrees of freedom that the slave hydraulic manipulator cannot achieve with other achievable motion degrees of freedom into a single dimension of the irregular workspace, according to the generalized Euler's law. This ensures that the slave hydraulic manipulator can traverse any position in any dimension of the irregular workspace.

[0078] In the slave-end heterogeneous workspace and the master-end heterogeneous workspace, if the direction of the joint motion degree of freedom of the m-th dimension in the slave-end heterogeneous workspace and the m-th dimension in the master-end heterogeneous workspace is the same, then the m-th dimension in the slave-end heterogeneous workspace and the m-th dimension in the master-end heterogeneous workspace are isomorphic dimensions, and the remaining dimensions in the slave-end heterogeneous workspace and the master-end heterogeneous workspace are non-isomorphic dimensions.

[0079] A dimension is considered isomorphic when its index and the direction of the joint's degrees of freedom are the same.

[0080] The second step involves using the heterogeneous workspaces of the slave hydraulic manipulator and the master device to match the dimensions between them using a teleoperation command adaptive mapping method, ultimately achieving master-slave heterogeneous matching for teleoperation of the hydraulic manipulator.

[0081] To address the potential discrepancy in the number of degrees of freedom between the slave-end hydraulic manipulator and the master-end device, leading to a mismatch in workspace dimensions, a method for constructing a non-standard workspace is proposed to integrate the workspace dimensions of both. Based on the created non-standard workspace, a novel adaptive mapping method for teleoperation commands is proposed to fully utilize the slave-end workspace and ensure accurate reproduction of the hydraulic manipulator's teleoperation commands during actual operation.

[0082] In the second step, based on the irregular workspaces of the slave hydraulic manipulator and the master device, an adaptive mapping method for teleoperation commands is used to match the slave hydraulic manipulator and the master device, as follows:

[0083] 2.1) For each isomorphic dimension in the slave heteromorphic workspace and the master heteromorphic workspace, establish an isomorphic dimension position-position mapping model, input the actual operation instructions of the isomorphic dimension into the isomorphic dimension position-position mapping model, and output the isomorphic dimension instruction mapping result.

[0084] In step 2.1), the isomorphic dimension position-position mapping model is as follows:

[0085]

[0086] in, and Pm These are the isomorphic dimension instruction mapping result and the isomorphic dimension actual operation instruction, respectively, and f() is the position-position mapping function.

[0087] isomorphic dimension instruction mapping results and isomorphic dimension actual operation instruction P m Specifically, these are the coordinates on the isomorphic dimensions of the slave-end heterogeneous workspace and the master-end heterogeneous workspace, respectively.

[0088] When dimension one (D1) is a "homogeneous dimension", the mapping mode of the master and slave heterogeneous workspace dimensions (D1) is defined as a proportional position-position mapping, that is:

[0089]

[0090] in, and λ represents the coordinates on dimension 1 (D1) of the heterogeneous workspace of the master and slave ends, respectively, and λ is the scaling factor.

[0091] 2.2) For each non-isomorphic dimension in the slave-end heteromorphic workspace and the master-end heteromorphic workspace, establish a non-isomorphic dimension location-location mapping model, input the adaptive decision factor of the master-end device into the non-isomorphic dimension location-location mapping model, and output the non-isomorphic dimension instruction mapping result.

[0092] In step 2.2), to fully traverse the slave workspace and achieve accurate teleoperation tasks, three command mapping modes are set, and command mapping on the "non-homogeneous dimension" is implemented through adaptive switching. The three command mapping modes are: navigation mapping mode, positioning mapping mode, and transition mapping mode; the homogeneous dimension position-position mapping model is as follows:

[0093]

[0094] in, This is the result of mapping non-isomorphic dimension instructions; P N P T and P P These are the navigation mapping results, transition mapping results, and positioning mapping results, respectively; R m R is the distance between the position of the endpoint of the master device in the non-isomorphic dimension of the master's heterogeneous workspace and the center point of the non-isomorphic dimension, i.e., the adaptive decision factor; N and R PThese are a first mode switching distance threshold and a second mode switching distance threshold. These thresholds can be used to divide the “non-homogeneous dimension” heterogeneous workspace into three mapping regions. When the end point of the master device is located in a different mapping region in the master “non-homogeneous dimension” heterogeneous workspace, the corresponding instruction mapping mode is executed.

[0095] Considering that the operator can directly control the end point of the master device to freely reach any position within the master-side heterogeneous workspace, the distance R between the position of the end point of the master device in the master-side "non-isomorphic" heterogeneous workspace and the center point of the master-side "non-isomorphic" heterogeneous workspace is used. m It serves as an adaptive decision factor for determining the adaptive instruction mapping mode.

[0096] Navigation mapping result P N Specifically as follows:

[0097]

[0098]

[0099] in, The position of the end effector of the hydraulic robotic arm at the current moment in the non-isomorphic dimension of the irregular workspace at the end; v is the first derivative of the navigation mapping result, dt is the mapping instruction update time; max The preset maximum mapping speed is designed to ensure that the mapping instructions do not change drastically within a short period of time; vec(R m R is the adaptive decision factor. m The unit direction vector.

[0100] The navigation mapping method is similar to the common position-velocity mapping method. The direction and distance of the vector determined by the vector direction and distance determined by the direction and magnitude of the speed change of the mapping command.

[0101] Transition mapping result P T Specifically as follows:

[0102]

[0103]

[0104] Where, α T It is the transition mapping factor, which varies with the adaptive decision factor R. m It changes with the changes; and These are the reference results obtained at the current moment using navigation mapping and positioning mapping methods, respectively.

[0105] Location mapping result P P Specifically as follows:

[0106]

[0107]

[0108]

[0109]

[0110] in, These are the single-axis mapping results for the first, second, ..., i, ..., m non-isomorphic dimensions, respectively; λ VOM This is the scaling factor for a single-axis mapping. and The actual operation instructions in the non-isomorphic dimension and the focus of the heterogeneous workspace in the "non-isomorphic dimension" at the i-th non-isomorphic dimension D are respectively. ni Coordinates on the axis; To create a heterogeneous workspace with a "non-isomorphic dimension" at the i-th non-isomorphic dimension D ni Midpoint of the mapping on the axis; σ VOM Set the preset scaling factor; and The non-isomorphic dimensions of the heterogeneous workspace at the ith non-isomorphic dimension axis D are respectively... ni The maximum and minimum values ​​on.

[0111] 2.3) Establish a teleoperation command adaptive mapping model. Input the isomorphic dimension command mapping result and the non-isomorphic dimension command mapping result into the teleoperation command adaptive mapping model. The teleoperation command adaptive mapping model outputs the final teleoperation command adaptive mapping result, which will transform the coordinates of the master device in various dimensions to the slave hydraulic manipulator, and finally realize the master-slave heterogeneous matching of the hydraulic manipulator teleoperation.

[0112] In step 2.3), the teleoperation command adaptive mapping model is as follows:

[0113]

[0114] Among them, P map For the final adaptive mapping result of teleoperation commands, and These are the instruction mapping results for homogeneous dimensions and the adaptive instruction mapping results for non-homogeneous dimensions, respectively; O() is the sorting function according to the heterogeneous workspace dimensions.

[0115] Taking the example robotic arm as an example, its final instruction mapping result is as follows:

[0116]

[0117] in, and These are the adaptive instruction mapping results on the "non-isomorphic dimensions" D2, D3, and D4, respectively.

[0118] In the first step, considering the physical configuration differences between the hydraulic robotic arm and the master device, a heterogeneous workspace, distinct from traditional Cartesian space, is established. In the second step, the dimensions of this heterogeneous workspace are divided into "isomorphic dimensions" and "non-isomorphic dimensions," and position-to-position mapping and adaptive mapping are performed on each, ultimately yielding an adaptive command mapping result. The proposed novel teleoperation command adaptive mapping method, TWAM, based on a heterogeneous workspace, enables perfect reproduction of master-slave operation commands on the slave end in heterogeneous master-slave scenarios during hydraulic robotic arm teleoperation, thereby improving the actual completion effect of hydraulic robotic arm teleoperation tasks and enhancing the teleoperation capability of the hydraulic robotic arm.

[0119] After obtaining the final teleoperation command adaptive mapping result P map Then, the mapping result points are transformed into continuous target trajectories with time axes through path interpolation algorithm; then, the continuous target trajectory is calculated into the joint space of the hydraulic manipulator by inverse kinematics solver to obtain the joint tracking trajectory; in addition, each joint is controlled to follow the joint tracking trajectory by the nonlinear controller of the hydraulic manipulator, and finally the operation command issued by the master operator is realized and the teleoperation task is completed.

[0120] Specific embodiments of the present invention are as follows:

[0121] This invention uses a hydraulic robotic arm as an example for explanation. The structure of the example hydraulic robotic arm is as follows: Figure 2 As shown, the master robot has six degrees of freedom, and the slave robot has four degrees of freedom; they are matched via a communication channel. It is worth noting that although the following content of this invention will focus on the example robotic arm, it does not mean that the method proposed in this invention is only applicable to this specific type of hydraulic robotic arm. On the contrary, this method is generally applicable to all hydraulic robotic arms. The specific implementation technical solution of the method proposed in this invention is as follows:

[0122] 1) Construct irregularly shaped workspaces:

[0123] ① Taking the number of degrees of freedom of the hydraulic robotic arm at the slave end as 4 as a reference, the dimension of the irregular workspace is also set to 4.

[0124] ② Based on the degree of freedom settings of the master and slave devices and the requirements of the actual teleoperation task, each dimension of the irregular workspace is defined separately. The hydraulic robotic arm in this invention example is only a four-degree-of-freedom hydraulic robotic arm and cannot achieve rotational movement. Therefore, when defining the dimensions of the irregular workspace, it needs to be combined with other degrees of freedom. The specific dimensions of this irregular workspace are set as follows:

[0125] Dimension 1 (D1): The direction of rotation of the first joint.

[0126] Dimension 2 (D2): The horizontal distance between the end of the master device (or the slave hydraulic robot) and the base.

[0127] Dimension 3 (D3): Vertical distance between the end of the master device (or slave hydraulic manipulator) and the base.

[0128] Dimension 4 (D4): The direction in which the end point is rotated around the specified axis I in Cartesian space by an angle R.

[0129] The dimensional definition of this irregular workspace is somewhat representative. Its first dimension (D1) is defined based on the master-slave degree of freedom relationship, through... Figure 2 It is known that the first joint motion degree of freedom of the master device and the slave hydraulic manipulator are in the same direction. Therefore, the first dimension of the irregular workspace is defined as this direction, and the irregular workspace dimensions set according to this definition are collectively referred to as "isomorphic dimensions", while the other dimensions are collectively referred to as "non-isomorphic dimensions". The second and third dimensions of the irregular workspace are defined based on the actual teleoperation task requirements. Generally speaking, the purpose of teleoperation of hydraulic manipulators is to complete specific tasks through the end effector. Therefore, it is necessary to define the mapping command to the end effector. Thus, the second and third dimensions of the irregular workspace are defined as the horizontal and vertical distances between the end effector of the master device (or the slave hydraulic manipulator) and the base, respectively. The fourth dimension (D4) of the irregular workspace is defined based on the combination of the unrealizable degree of freedom and the realizable degree of freedom. According to the generalized Euler's law, each direction in three-dimensional space can be represented by rotating a specific angle around a specific axis. Therefore, the fourth dimension (D4) of the irregular workspace is defined as the direction in which the end effector rotates an angle R around a specified axis I in Cartesian space.

[0130] ③ Based on the definitions of each dimension of the heterogeneous workspace, convert the master and slave workspaces into master and slave heterogeneous workspaces.

[0131] 2) Perform adaptive instruction mapping:

[0132] 2.1) For each "isomorphic dimension" of the heterogeneous workspace, a position-to-position mapping is performed, that is, using a simple function as the transformation relationship, the coordinates of the master device in that dimension are transformed to the corresponding dimension of the slave device; taking the teleoperation configuration of this invention as an example, since dimension one (D1) is an "isomorphic dimension", the mapping mode of the master and slave heterogeneous workspace dimensions (D1) is defined as proportional position-to-position mapping, that is:

[0133]

[0134] in, and λ represents the coordinates on dimension 1 (D1) of the heterogeneous workspace of the master and slave ends, respectively, and λ is the scaling factor.

[0135] 2.2) For instruction coordinate mapping in "non-isomorphic dimensions," this invention proposes a novel adaptive instruction mapping method. To facilitate method explanation, an example teleoperation configuration is established with master and slave heterogeneous "non-isomorphic dimensions" workspaces, such as... Figure 3 As shown, Figure 3 As shown in (a), the master and slave "non-isomorphic" heterogeneous workspaces are established, as follows: Figure 3 As shown in (b), this is a schematic diagram of the adaptive mapping space and decision factor. Since a preset first mode switching distance threshold and a preset second mode switching distance threshold are defined, the main-end "non-isomorphic dimension" heterogeneous workspace is divided into three mapping regions: the positioning mapping region (with the focus of the main-end "non-isomorphic dimension" heterogeneous workspace as the sphere center, R...). P A spherical region with radius R), a transition mapping region (centered on the focal point of the "non-isomorphic dimension" heterogeneous workspace at the main end, R) N The region within a sphere of radius R (excluding the positioning mapping region) and the navigation mapping region (excluding the positioning mapping region and the transition mapping region within the master-side "amorphous dimension" heterogeneous workspace). When the master-side device's endpoint is located in a different mapping region within the master-side "amorphous dimension" heterogeneous workspace, the corresponding command mapping mode is executed. op The vector is the distance from the focus of the master-side "non-isomorphic" heterogeneous workspace to the location of the actual operation command sent by the operator within the master-side "non-isomorphic" heterogeneous workspace.

[0136] 2.2.1) Considering that the operator can directly control the end point of the master device to freely reach any position in the master-end heterogeneous workspace, the distance R between the position of the end point of the master device in the master-end "non-isomorphic dimension" heterogeneous workspace and the center point of the master-end "non-isomorphic dimension" heterogeneous workspace is used. m As an adaptive decision factor, adaptive command mapping mode determination is performed; when the position of the end point of the master device in the heterogeneous workspace of the master device is in different mapping regions, the corresponding command mapping mode is executed. An example of the mapping mode region division in teleoperation configuration is as follows: Figure 3 As shown.

[0137] 2.2.2) The specific implementation methods of navigation mapping mode, positioning mapping mode and transition mapping mode will be explained next:

[0138] Navigation mapping: This mapping method is similar to the common position-velocity mapping method. The direction and distance of the vector determined by the mapping command's speed change direction and magnitude.

[0139] Positioning Mapping: In order to reproduce operation commands more accurately during teleoperation tasks, this invention proposes a novel axis-by-axis precise command mapping method, VOM, in the positioning mapping mode.

[0140] To better illustrate the VOM method, we will use an example robotic arm as a representative example. Figure 4 It should be noted that this method is not only applicable to the example robotic arm, but is effective for all hydraulic robotic arms:

[0141] The example robotic arm has three "non-isomorphic dimensions" D2, D3, and D4. Based on observation, the distribution of its non-isomorphic workspace regions along the D2 axis is clear and well-defined, as shown below. Figure 4 As shown in (a), it can be directly determined from the distribution map. and And determine

[0142] In addition, such as Figure 4 As shown in (b), since the distribution of the "amorphous dimension" irregular workspace of the example robot arm on the D2-D4 plane is clear and well-defined, after determining the maximum and minimum values ​​of the region on the D2 axis, the region of the "amorphous dimension" irregular workspace of the example robot arm and the straight line are found in the D2-D4 plane. The two intersection points, the D4 direction coordinates of the two intersection points are... and Finish and After the measurement, it can be determined

[0143] Finally The determination first involves defining the heterogeneous workspace of the "non-isomorphic dimension" at the end through a straight line. And the section region parallel to the base plane D2-D3, then we discuss two cases: when this region is parallel to the straight line When there are only two intersection points, such as Figure 4 As shown in (c). Then, confirm... Similarly, find the cross-sectional area and the straight line. The two intersection points, the D3 direction coordinates of the two intersection points are... and Finish and After the measurement, it can be determined When the region is aligned with a straight line When there are more than two intersection points, such as Figure 4 As shown in (d), find the intersection of this cross-sectional area and the straight line. The two intersection points with the smallest coordinate values ​​on the D2 axis are the D3 direction coordinates of these two intersection points. and Finish and After the measurement, it can be determined

[0144] Complete in sequence and After the measurement, the final example robotic arm's mapping instructions in the "non-isomorphic dimension" can be determined as follows:

[0145]

[0146] Transition mapping:

[0147] The transition mapping method designed in this invention is as follows:

[0148]

[0149]

[0150] Where, α T It is a transition mapping factor, which varies with the distance R between the position of the end point of the master device in the master's "non-isomorphic dimension" heterogeneous workspace and the center point of the master's "non-isomorphic dimension" heterogeneous workspace. m It changes with the changes; and These are the mapping reference results obtained at that moment using navigation mapping and positioning mapping methods, respectively.

[0151] 2.2.3) After sequentially completing the mapping of "isomorphic dimension" and "non-isomorphic dimension", the final adaptive mapping result of the novel teleoperation command based on the heterogeneous workspace is as follows: Taking the example robotic arm, the final command mapping result is:

[0152]

[0153] in, and These are the adaptive instruction mapping results on the "non-isomorphic dimensions" D2, D3, and D4, respectively.

[0154] Finally, comparative experiments and specific grasping task experiments were conducted on the above method based on an example hydraulic robotic arm and an example teleoperation configuration to verify the effectiveness and reliability of the method proposed in this invention.

[0155] Experiment 1: Comparative Experiment

[0156] This experiment is based on a set of master end command points in a pre-given "non-isomorphic" heterogeneous workspace. The designed TWAM method and the traditional position-position mapping method PPM are used to map the commands, and the results obtained by the two methods are compared and examined.

[0157] In this experiment, the master-end command point set within the given "non-isomorphic dimension" irregular workspace was uniformly obtained using the Monte Carlo method within the master-end "non-isomorphic dimension" irregular workspace. Based on practical experience, command point sets obtained through mapping that are more similar to the slave-end hydraulic manipulator's "non-isomorphic dimension" irregular workspace result in better practical performance. The final comparative experimental results are as follows: Figure 5 As shown, Figure 5 (a) is the mapping result obtained by the method proposed in this patent. Figure 5 (b) is the mapping result obtained by the traditional position-position mapping method.

[0158] The performance parameters of the experiment are shown in Table 1. AUR represents the proportion of the mapping instruction point set in the slave-side "non-isomorphic dimension" heterogeneous workspace, and KNN represents the similarity between the mapping instruction point set and the slave-side "non-isomorphic dimension" heterogeneous workspace.

[0159] Table 1 Performance Comparison of Instruction Mapping Method

[0160]

[0161] Experimental results show that, compared with the traditional position-to-position mapping method PPM, the TWAM method proposed in this invention can ensure high similarity and a large proportion of the mapped command point set in the "non-isomorphic dimension" heterogeneous workspace. This means that in the actual remote operation of the hydraulic robotic arm, the proposed TWAM method can more accurately reproduce the master-end operation commands based on the actual configuration and actual working space of the slave robotic arm, and make fuller use of the slave-end working space.

[0162] Experiment 2: Specific Grabbing Task Experiment

[0163] After verifying the good performance of the proposed method in the "non-isomorphic dimension" through Experiment 1, the TWAM method proposed in this invention was used to complete a specific grasping task of master-slave heterogeneous teleoperation of a hydraulic manipulator. The specific grasping task set by this invention is: under the harsh conditions of underwater, using the TWAM method proposed in this invention, to teleoperate a hydraulic manipulator to grasp three targets of different sizes, weights, and locations, and then transport and place them on a designated underwater platform. The specific experimental process is as follows... Figure 6 As shown.

[0164] pass Figure 6 It can be seen that in the actual remote operation of the hydraulic robotic arm based on the TWAM method proposed in this invention, the command mapping mode can be adaptively switched by the position of the command point sent by the master operator in real time in the irregular workspace, and finally the adaptive mapping command is obtained, and the grasping and placement of different targets can be completed smoothly and accurately.

[0165] The command mapping results during actual teleoperation operations are as follows: Figure 7 As shown,

[0166] Figure 7 (a) is the operation instruction sent in real time by the master operator. Figure 7 (b) is the real-time mapping instruction result obtained through the mapping method designed in this patent. Figure 7 It can be seen that when R m >R N Navigation mapping is achieved during the remote operation of the hydraulic robotic arm. When R P <R m ≤R N Transition mapping is achieved during the remote operation of the hydraulic robotic arm, when R m ≤R P Positioning mapping is achieved during the remote operation of the hydraulic robotic arm.

[0167] The two experiments above demonstrate that, compared with the traditional position-position mapping method, the novel adaptive mapping method for teleoperation commands based on heterogeneous workspace proposed in this invention can fully utilize the slave-end workspace and ensure the accurate reproduction of the teleoperation commands of the hydraulic robotic arm during actual operation, ultimately significantly improving the teleoperation effect of the hydraulic robotic arm in the case of master-slave heterogeneity.

[0168] The above content is merely a technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace, characterized in that, include: The first step is to establish an irregular workspace for the slave hydraulic manipulator and the master device when the degrees of freedom are inconsistent. The second step is to use the adaptive mapping method of teleoperation commands to match the dimensions between the slave hydraulic manipulator and the master device based on the heterogeneous workspace of the slave hydraulic manipulator and the master device, so as to finally realize the master-slave heterogeneous matching of the teleoperation of the hydraulic manipulator. In the first step described above, the irregularly shaped workspaces of the slave-end hydraulic robotic arm and the master-end equipment are as follows: a) Irregularly shaped workspace at the slave end of the hydraulic robotic arm: The dimension of the slave-end irregular workspace is set to be consistent with the number of degrees of freedom n of the slave-end hydraulic manipulator. In the six degrees of freedom in the three-dimensional space, several degrees of freedom not included in the slave-end hydraulic manipulator are integrated into several degrees of freedom included in the slave-end hydraulic manipulator using the generalized Euler's law method. Finally, the workspace of the slave-end hydraulic manipulator is transformed into the slave-end irregular workspace. b) Irregular workspace of the master device: The dimensions of the main end irregular workspace are set to be consistent with the number of degrees of freedom n of the slave end hydraulic manipulator; in the six degrees of freedom in the three-dimensional space, several degrees of freedom not included in the main end device are integrated into several degrees of freedom included in the main end device using the generalized Euler's law method, and finally the workspace of the main end device is transformed into the main end irregular workspace. In the aforementioned slave-end heterogeneous workspace and master-end heterogeneous workspace, if the direction of the joint motion degree of freedom of the m-th dimension in the slave-end heterogeneous workspace and the m-th dimension in the master-end heterogeneous workspace is the same, then the m-th dimension in the slave-end heterogeneous workspace and the m-th dimension in the master-end heterogeneous workspace are isomorphic dimensions, and the remaining dimensions in the slave-end heterogeneous workspace and the master-end heterogeneous workspace are non-isomorphic dimensions.

2. The master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace as described in claim 1, characterized in that: In the first step, the inconsistency of degrees of freedom between the slave hydraulic manipulator and the master device specifically refers to the inconsistency in the number of degrees of freedom and / or rotation direction of the joints of the slave hydraulic manipulator and the master device.

3. The master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace as described in claim 1, characterized in that: In the second step, based on the irregular workspaces of the slave hydraulic manipulator and the master device, a teleoperation command adaptive mapping method is used to match the slave hydraulic manipulator and the master device, as follows: 2.1) For each isomorphic dimension in the slave heteromorphic workspace and the master heteromorphic workspace, establish an isomorphic dimension position-position mapping model, input the actual operation instructions of the isomorphic dimension into the isomorphic dimension position-position mapping model, and output the isomorphic dimension instruction mapping result. 2.2) For each non-isomorphic dimension in the slave-end heteromorphic workspace and the master-end heteromorphic workspace, establish a non-isomorphic dimension position-position mapping model, input the adaptive decision factor of the master-end device into the non-isomorphic dimension position-position mapping model, and output the non-isomorphic dimension instruction mapping result. 2.3) Establish a teleoperation command adaptive mapping model. Input the isomorphic dimension command mapping result and the heteromorphic dimension command mapping result into the teleoperation command adaptive mapping model. The teleoperation command adaptive mapping model outputs the final teleoperation command adaptive mapping result, which will transform the coordinates of the master device in various dimensions to the slave hydraulic robotic arm, and finally realize the master-slave heterogeneous matching of the hydraulic robotic arm teleoperation.

4. The master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace according to claim 3, characterized in that: In step 2.1), the isomorphic dimension position-position mapping model is as follows: in, and These are the isomorphic dimension instruction mapping results and the isomorphic dimension actual operation instructions, respectively. For position-to-position mapping functions; isomorphic dimension instruction mapping results and isomorphic dimension actual operation instructions Specifically, these are the coordinates on the isomorphic dimensions of the slave-end heterogeneous workspace and the master-end heterogeneous workspace, respectively.

5. The master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace according to claim 3, characterized in that: In step 2.2), the isomorphic dimension position-position mapping model is as follows: in, This is the result of mapping non-isomorphic dimension instructions; , and These are the navigation mapping results, transition mapping results, and positioning mapping results, respectively. The distance between the position of the end point of the main device in the non-isomorphic dimension of the main device's heterogeneous workspace and the center point of the non-isomorphic dimension is the adaptive decision factor. and These are the preset first mode switching distance threshold and the preset second mode switching distance threshold, respectively.

6. The master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace according to claim 5, characterized in that: The navigation mapping results Specifically as follows: in, The position of the end effector of the hydraulic robotic arm at the current moment in the non-isomorphic dimension of the irregular workspace at the end; The first derivative of the navigation mapping result, For the mapping instruction update time; The preset maximum mapping speed; Adaptive decision factor The unit direction vector.

7. The master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace according to claim 5, characterized in that: The transition mapping result Specifically as follows: in, Transition mapping factor; and These are the reference results obtained at the current moment using navigation mapping and positioning mapping methods, respectively.

8. The master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace according to claim 5, characterized in that: The location mapping result Specifically as follows: in, These are the single-axis mapping results for the first, second, ..., i, ..., m non-isomorphic dimensions, respectively. This is the scaling factor for a single-axis mapping. and The actual operation instructions in the non-isomorphic dimension and the focus of the heterogeneous workspace in the "non-isomorphic dimension" at the i-th non-isomorphic dimension are respectively. Coordinates on the axis; To provide a heterogeneous workspace for the i-th non-isomorphic dimension from the end. Midpoint of the mapping on the axis; Set the preset scaling factor; and These represent the non-isomorphic dimensions of the heterogeneous workspace at the i-th non-isomorphic dimension axis. The maximum and minimum values ​​on.

9. The master-slave heterogeneous matching method for remote operation of a hydraulic robotic arm based on a heterogeneous workspace according to claim 5, characterized in that: In step 2.3), the teleoperation command adaptive mapping model is as follows: in, For the final adaptive mapping result of teleoperation commands, and These are the instruction mapping results for homogeneous dimensions and the adaptive instruction mapping results for non-homogeneous dimensions, respectively. This is a sorting function based on the dimensions of the irregular workspace.

Images