Exoskeleton pole operation terminal load dynamic estimation method and system

Abstract

The application discloses a kind of exoskeleton hanging pole operating terminal load dynamic estimation method and system, exoskeleton upper limb mechanical model is established to solve the force of hanging pole to exoskeleton clamp at the position of double-arm operating terminal, it is beneficial to estimate the mechanical state of exoskeleton operating terminal;According to the kinematic model of exoskeleton upper limb, the position and distance of double-arm operating terminal are solved, which is beneficial to determine the relative position relationship of double-arm;According to the distance of double-arm operating terminal and the force of hanging pole to exoskeleton clamp at the position of double-arm operating terminal and the mechanical model of hanging pole, the mass and barycenter position of hanging pole are solved, which is beneficial to the selection and determination of exoskeleton control scheme, realizes the accurate estimation of the weight and centroid of the load of exoskeleton hanging pole operating terminal, so as to perceive and distinguish the use state of exoskeleton robot, improve the technical effect of control precision.

Description

Technical Field

[0001] This invention relates to the field of exoskeleton robot technology, and in particular to a method and system for dynamically estimating the load of an exoskeleton pole operation terminal. Background Technology

[0002] An exoskeleton robot system is a human-robot collaborative system that enhances the wearer's strength in various environments. The human operator is only responsible for the exoskeleton robot's position control, force control, and motion signal generation. The structure of the exoskeleton robot's pole operating system is as follows: Figure 2 As shown, Figure 2 In this diagram, 1 represents the exoskeleton back frame, 2 represents the exoskeleton upper arm, 3 represents the exoskeleton forearm, and 4 represents the exoskeleton operating terminal fixture. The shoulder joint connects the exoskeleton back frame 1 and the exoskeleton upper arm 2, the elbow joint connects the exoskeleton upper arm 2 and the exoskeleton forearm 3, and the wrist joint connects the exoskeleton forearm 3 and the exoskeleton fixture 4. 5 represents the exoskeleton operating handle, and 6 represents the hanging rod. The exoskeleton operating handle 5 is connected to the exoskeleton fixture 4 via a six-dimensional force sensor 7, which collects the human-machine interaction force when operating the handle. Currently, exoskeleton robots primarily control joints by using joint angle information and the mechanical information of the operating terminal during upper limb hanging rod operation. However, the load information of the operating terminal is usually unknown. In actual control, the rods held by the operating terminal often vary significantly, and their weight and center of gravity position affect the control effect. Therefore, it is necessary to accurately estimate the weight and center of gravity of the load on the exoskeleton hanging rod operating terminal to facilitate the perception and identification of the exoskeleton robot's usage status and improve control accuracy. Summary of the Invention

[0003] This invention provides a method and system for dynamic estimation of the load of an exoskeleton pole operating terminal, which is used to accurately estimate the weight and center of gravity of the load of the exoskeleton pole operating terminal, so as to facilitate the perception and identification of the usage status of the exoskeleton robot and improve control accuracy.

[0004] In view of this, the first aspect of the present invention provides a method for dynamically estimating the load of an exoskeleton pole operation terminal, comprising:

[0005] A biomechanical model of the upper limbs of the exoskeleton was established, and the force exerted by the hanging rod at the end position of the two arms on the exoskeleton clamp was solved.

[0006] A kinematic model of the upper limb of the exoskeleton was established. The relationship between the position of the dual-arm manipulator and the joint angle was analyzed based on the DH parameters, and the position of the dual-arm manipulator was solved.

[0007] Calculate the distance between the two-arm operating terminals based on their positions.

[0008] A mechanical model of the hanging pole is established. Based on the distance between the two-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the two-arm operating terminals, the mass and center of gravity of the hanging pole are calculated.

[0009] Optionally, an exoskeleton upper limb biomechanical model is established, and the force exerted by the hanging rod at the end position of the dual arms on the exoskeleton clamp is solved, including:

[0010] Obtain the angle, angular velocity, and angular acceleration information of each joint in the upper limb of the exoskeleton, and establish a mechanical model of the upper limb of the exoskeleton. The mechanical model of the upper limb of the exoskeleton is as follows:

[0011]

[0012] Where, τ d To maintain the joint torque for upper limb movement, M(θ) is the mass matrix, and θ is the angle at the joint. The angular acceleration at the joint. The angular velocity at the joint. G(θ) is the vector of centrifugal force and Coriolis force, and G(θ) is the vector of gravity.

[0013] Based on the force exerted on the exoskeleton's upper limb distal end during the wearer's operation, the mapped torque of the hand force at each joint position is calculated using the following formula:

[0014] τ h =J T F h

[0015] Where, τ h J is the mapped torque of the hand force at each joint position. T Let F be the transpose of the Jacobian matrix J. h The force applied to the extremities of the exoskeleton during the wearer's operation;

[0016] The output torque of the joint drive is calculated based on the feedback current obtained from each joint motor. The calculation formula is as follows:

[0017] τ m =k i n r i m

[0018] Where, τ m k is the output torque of the joint drive. i Let n be the torque constant of the joint motor. r i is the reduction ratio of the reducer. m The feedback current obtained by the joint motor;

[0019] Based on the output torque of the joint drive, the mapped torque of the hand force at each joint position, and the joint torque maintaining upper limb movement, the mapped torque of the operating terminal rod pressure at each joint position is calculated using the following formula:

[0020] τ b =τ d -τ h -τ m

[0021] Where, τ b The mapped torque of the operating terminal arm pressure at each joint position;

[0022] The force exerted by the hanging rod on the exoskeleton at the dual-arm operating terminal position is calculated based on the mapped torque of the pressure on the hanging rod at each joint position. The formula for calculating the force exerted by the hanging rod on the exoskeleton at the dual-arm operating terminal position is as follows:

[0023]

[0024] Among them, F b The force exerted by the hanging rod at the single-arm operation terminal position on the exoskeleton clamp.

[0025] Optionally, an exoskeleton upper limb kinematic model is established, and the relationship between the position of the dual-arm manipulator end effector and the joint angle is analyzed based on the DH parameters to solve for the position of the dual-arm manipulator end effector, including:

[0026] Establish an exoskeleton upper limb kinematic model;

[0027] Based on the DH parameter analysis, the relationship between the position of the dual-arm operating terminal and the joint angle is obtained, and the coordinate rotation matrix of each arm is obtained.

[0028] Based on the coordinate rotation matrices of each arm, calculate the coordinate positions of the operating terminals of the two arms relative to the back frame.

[0029] The position of the dual-arm operating terminal is calculated based on its coordinate position relative to the back frame.

[0030] Optionally, the formula for calculating the distance between the two-arm operating terminals based on their positions is as follows:

[0031] L = |V b |=P h1 -P h2

[0032] Where L is the distance between the dual-arm operating terminals, and V b Let P be the spatial vector formed by the dual-arm operating terminals. h1 Let P be the coordinate position of the first single-arm operating terminal relative to the back frame. h2The coordinates of the second single-arm operating terminal relative to the back frame.

[0033] Optionally, a mechanical model of the hanging pole is established. Based on the distance between the dual-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the hanging pole are calculated, including:

[0034] Establish a mechanical model for the hanging rod. The mechanical model of the hanging rod is as follows:

[0035]

[0036] In the exoskeleton's joint coordinate system, the x-axis represents the projection of the extension direction of the hanging rod onto the horizontal plane, the y-axis represents the projection of the forearm extension direction onto the horizontal plane and perpendicular to the x-axis, and the z-axis represents the vertical direction. F b1z F represents the z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the first single-arm operating terminal position. b2z Let α be the z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the position of the second single-arm operating terminal, α be the real-time attitude angle of the hanging rod, D be the distance between the center of mass of the hanging rod and the nearest single-arm operating terminal, m be the mass of the hanging rod, and g be the acceleration due to gravity.

[0037] Based on the distance between the dual-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the hanging pole are calculated using the following formula:

[0038]

[0039]

[0040] G = L + D

[0041] Where G is the position of the center of gravity of the hanging rod.

[0042] A second aspect of this invention provides a dynamic load estimation system for an exoskeleton pole operation terminal.

[0043] include:

[0044] The upper limb biomechanics solution module is used to establish the upper limb biomechanics model of the exoskeleton and solve the force exerted by the hanging rod at the end position of the two arms on the exoskeleton clamp.

[0045] The terminal distance calculation module is used to establish the kinematic model of the upper limb of the exoskeleton, analyze the relationship between the position of the dual-arm operating terminal and the joint angle based on the DH parameters, solve the position of the dual-arm operating terminal, and calculate the distance between the dual-arm operating terminals based on the position of the dual-arm operating terminals.

[0046] The pole information calculation module is used to establish a mechanical model of the pole. Based on the distance between the dual-arm operating terminals and the force exerted by the pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the pole are calculated.

[0047] Optionally, the upper limb biomechanics solution module is specifically used for:

[0048] Obtain the angle, angular velocity, and angular acceleration information of each joint in the upper limb of the exoskeleton, and establish a mechanical model of the upper limb of the exoskeleton. The mechanical model of the upper limb of the exoskeleton is as follows:

[0049]

[0050] Where, τ d To maintain the joint torque for upper limb movement, M(θ) is the mass matrix, and θ is the angle at the joint. The angular acceleration at the joint. The angular velocity at the joint. G(θ) is the vector of centrifugal force and Coriolis force, and G(θ) is the vector of gravity.

[0051] Based on the force exerted on the exoskeleton's upper limb distal end during the wearer's operation, the mapped torque of the hand force at each joint position is calculated using the following formula:

[0052] τ h =J T F h

[0053] Where, τ h J is the mapped torque of the hand force at each joint position. T Let F be the transpose of the Jacobian matrix J. h The force applied to the extremities of the exoskeleton during the wearer's operation;

[0054] The output torque of the joint drive is calculated based on the feedback current obtained from each joint motor. The calculation formula is as follows:

[0055] τ m =k i n r i m

[0056] Where, τ m k is the output torque of the joint drive. i Let n be the torque constant of the joint motor. r i is the reduction ratio of the reducer. m The feedback current obtained by the joint motor;

[0057] Based on the output torque of the joint drive, the mapped torque of the hand force at each joint position, and the joint torque maintaining upper limb movement, the mapped torque of the operating terminal rod pressure at each joint position is calculated using the following formula:

[0058] τ b =τ d -τ h -τ m

[0059] Where, τ b The mapped torque of the operating terminal arm pressure at each joint position;

[0060] The force exerted by the hanging rod on the exoskeleton at the dual-arm operating terminal position is calculated based on the mapped torque of the pressure on the hanging rod at each joint position. The formula for calculating the force exerted by the hanging rod on the exoskeleton at the dual-arm operating terminal position is as follows:

[0061]

[0062] Among them, F b The force exerted by the hanging rod at the single-arm operation terminal position on the exoskeleton clamp.

[0063] Optionally, an exoskeleton upper limb kinematic model is established, and the relationship between the position of the dual-arm manipulator end effector and the joint angle is analyzed based on the DH parameters to solve for the position of the dual-arm manipulator end effector, including:

[0064] Establish an exoskeleton upper limb kinematic model;

[0065] Based on the DH parameter analysis, the relationship between the position of the dual-arm operating terminal and the joint angle is obtained, and the coordinate rotation matrix of each arm is obtained.

[0066] Based on the coordinate rotation matrices of each arm, calculate the coordinate positions of the operating terminals of the two arms relative to the back frame.

[0067] The position of the dual-arm operating terminal is calculated based on its coordinate position relative to the back frame.

[0068] Optionally, the formula for calculating the distance between the two-arm operating terminals based on their positions is as follows:

[0069] L = |V b |=P h1 -P h2

[0070] Where L is the distance between the dual-arm operating terminals, and V b Let P be the spatial vector formed by the dual-arm operating terminals. h1 Let P be the coordinate position of the first single-arm operating terminal relative to the back frame. h2The coordinates of the second single-arm operating terminal relative to the back frame.

[0071] Optionally, the pole information calculation module is specifically used for:

[0072] Establish a mechanical model for the hanging rod. The mechanical model of the hanging rod is as follows:

[0073]

[0074] In the exoskeleton's joint coordinate system, the x-axis represents the projection of the extension direction of the hanging rod onto the horizontal plane, the y-axis represents the projection of the forearm extension direction onto the horizontal plane and perpendicular to the x-axis, and the z-axis represents the vertical direction. F b1z F represents the z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the first single-arm operating terminal position. b2z Let α be the z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the position of the second single-arm operating terminal, α be the real-time attitude angle of the hanging rod, D be the distance between the center of mass of the hanging rod and the nearest single-arm operating terminal, m be the mass of the hanging rod, and g be the acceleration due to gravity.

[0075] Based on the distance between the dual-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the hanging pole are calculated using the following formula:

[0076]

[0077]

[0078] G = L + D

[0079] Where G is the position of the center of gravity of the hanging rod.

[0080] As can be seen from the above technical solutions, the method for dynamically estimating the load of the exoskeleton pole operation terminal provided by the present invention has the following advantages:

[0081] The present invention provides a method for dynamically estimating the load of an exoskeleton's slingshot-operated terminal. It establishes a mechanical model of the exoskeleton's upper limbs to solve for the force exerted by the slingshot on the exoskeleton clamp at the position of the dual-arm operating terminal, which is beneficial for estimating the mechanical state of the exoskeleton's operating terminal. Based on the kinematic model of the exoskeleton's upper limbs, it calculates the position and distance of the dual-arm operating terminals, which is beneficial for determining the relative positional relationship between the two arms. Based on the distance between the dual-arm operating terminals, the force exerted by the slingshot on the exoskeleton clamp at the position of the dual-arm operating terminals, and the mechanical model of the slingshot, it calculates the mass and center of gravity of the slingshot, which is beneficial for selecting and determining the exoskeleton's control scheme. This method achieves accurate estimation of the weight and center of gravity of the load on the exoskeleton's slingshot-operated terminal, facilitating the perception and identification of the exoskeleton robot's usage status and improving control accuracy.

[0082] The exoskeleton pole operation terminal load dynamic estimation system provided by this invention is used to execute the exoskeleton pole operation terminal load dynamic estimation method provided in this invention. Its principle and the technical effect achieved are the same as the exoskeleton pole operation terminal load dynamic estimation method provided in this invention, and will not be repeated here. Attached Figure Description

[0083] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0084] Figure 1 This is a flowchart illustrating a method for dynamically estimating the load of an exoskeleton pole operation terminal provided in this invention.

[0085] Figure 2 A schematic diagram of the operating system for the pole of an exoskeleton robot;

[0086] Figure 3 This is a schematic diagram illustrating the principle of a dynamic load estimation method for an exoskeleton pole operation terminal provided in this invention.

[0087] Figure 4 for Figure 2 A schematic diagram showing the establishment of the coordinate system in the corresponding structure;

[0088] Figure 5 This is a schematic diagram of the structure of an exoskeleton pole operation terminal load dynamic estimation system provided in this invention. Detailed Implementation

[0089] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0090] For easier understanding, please refer to Figure 1 , Figure 2 and Figure 3 This invention provides an embodiment of a method for dynamically estimating the load of an exoskeleton pole operating terminal, comprising:

[0091] Step 101: Establish the biomechanical model of the upper limbs of the exoskeleton and solve for the force exerted by the hanging rod at the end position of the two arms on the exoskeleton clamp.

[0092] It should be noted that sensors installed at various joint locations on the exoskeleton collect joint angle information θ and angular velocity information, and the angular acceleration information of the joints can be obtained through differential calculation. The six-dimensional force sensor at the dual-arm operating terminal can acquire the force F applied by the wearer to the upper limb distal end of the exoskeleton during operation. h The joint motor can obtain feedback current i m (Its magnitude reflects the actual driving torque of the joint during the control process). A coordinate system based on the shoulder position can be established according to the degrees of freedom of each joint (e.g., Figure 4 The coordinate system (Xt, Yt, Zt) in the figure, and the coordinate system that extends continuously toward the dual-arm operating terminal (including such as Figure 4 The coordinate system of the first single-arm wrist joint (Oh1, Xh1, Yh1, Zh1) and the coordinate system of the second single-arm wrist joint (Oh2, Xh2, Yh2, Zh2) are used. Using the angles, angular velocities, and angular accelerations of each joint as input, the torque τ that maintains the upper limb movement can be determined according to the dynamic equations. d (Exoskeleton upper limb biomechanical model) is as follows:

[0093]

[0094] Where, τ d To maintain the joint torque for upper limb movement, M(θ) is the mass matrix, and θ is the angle at the joint. The angular acceleration at the joint. The angular velocity at the joint. G(θ) is the vector of centrifugal force and Coriolis force, and G(θ) is the vector of gravity.

[0095] The six-dimensional force sensor at the dual-arm operating terminal can acquire the force F applied by the wearer to the upper limb end of the exoskeleton during operation. h Based on the force F applied to the exoskeleton's upper limb end during the wearer's operation. h Calculate the mapped torque τ of the hand force at each joint position. h The calculation formula is:

[0096] τ h =J T F h

[0097] Where, τ h J is the mapped torque of the hand force at each joint position. T Let F be the transpose of the Jacobian matrix J. h The force applied to the exoskeleton's upper limb end during the wearer's operation.

[0098] Based on the feedback current i obtained from each joint motorm Calculate the output torque τ of the joint drive m The calculation formula is:

[0099] τ m =k i n r i m

[0100] Where, τ m k is the output torque of the joint drive. i Let n be the torque constant of the joint motor. r i is the reduction ratio of the reducer. m The feedback current obtained by the joint motor.

[0101] Based on actual conditions, the exoskeleton moves in tandem with the human body under the influence of pressure from the control terminal levers, the force exerted by the human hand, and the driving force of the joints. At this point, if the mapped torque of the control terminal lever pressure at each joint position is τ... b The mapped torque of the force exerted by the human hand at each joint is τ. h The joint driving torque is τ m The inertial torque required to maintain upper limb movement is τ. d Then the following relationship exists:

[0102] τ b +τ h +τ m =τ d

[0103] Where, τ b This refers to the mapped torque of the operating terminal's hanging rod pressure at each joint position.

[0104] Therefore, based on the output torque of the joint drive, the mapped torque of the hand force at each joint position, and the joint torque maintaining upper limb movement, the mapped torque of the operating terminal rod pressure at each joint position is calculated using the following formula:

[0105] τ b =τ d -τ h -τ m

[0106] The force exerted by the hanging rod on the exoskeleton at the dual-arm operating terminal position is calculated based on the mapped torque of the pressure on the hanging rod at each joint position. The formula for calculating the force exerted by the hanging rod on the exoskeleton at the dual-arm operating terminal position is as follows:

[0107]

[0108] Among them, F b The force exerted by the hanging rod at the single-arm operation terminal position on the exoskeleton clamp.

[0109] The force exerted by the hanging rod at the first single-arm operating terminal position on the exoskeleton clamp is denoted as F. b1 The force exerted by the lever at the second single-arm operating terminal position on the exoskeleton clamp is denoted as F. b2 .

[0110] Step 102: Establish an exoskeleton upper limb kinematic model, analyze the relationship between the position of the dual-arm manipulator terminal and the joint angle based on the DH parameters, and solve for the position of the dual-arm manipulator terminal.

[0111] It should be noted that, by establishing a kinematic model of the upper limbs of the exoskeleton, and analyzing the relationship between the positions of the two arm manipulators and the joint angles θ based on the DH parameters, the coordinate rotation matrices T of each arm are obtained. Given the joint angle information θ, the positions of the two arm manipulators can be calculated based on their respective rotation matrices T. Then, based on the positions of the two arm manipulators and their respective rotation matrices, the coordinate positions P of the manipulators relative to the back frame can be calculated. Finally, the positions P of the two arm manipulators are obtained by calculating their coordinate positions relative to the back frame. h1 and P h2 .

[0112] Step 103: Calculate the distance between the dual-arm operating terminals based on their positions.

[0113] It should be noted that the formula for calculating the distance between the two-arm operating terminals based on their positions is as follows:

[0114] L = |V b |=P h1 -P h2

[0115] Where L is the distance between the dual-arm operating terminals, and V b Let P be the spatial vector formed by the dual-arm operating terminals. h1 Let P be the coordinate position of the first single-arm operating terminal relative to the back frame. h2 The coordinates of the second single-arm operating terminal relative to the back frame.

[0116] Step 104: Establish the mechanical model of the hanging pole. Based on the distance between the two-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the two-arm operating terminals, calculate the mass and center of gravity of the hanging pole.

[0117] It should be noted that the force exerted by the lever at the first single-arm operating terminal position on the exoskeleton clamp is F. b1 The force exerted by the hanging rod at the second single-arm operating terminal position on the exoskeleton clamp is F. b2Let the distance between the dual-arm operating terminals be L, and assuming the real-time attitude angle of the pole is α, then the mechanical model of the pole is:

[0118]

[0119] In the exoskeleton's joint coordinate system, the x-axis represents the projection of the extension direction of the hanging rod onto the horizontal plane, the y-axis represents the projection of the forearm extension direction onto the horizontal plane and perpendicular to the x-axis, and the z-axis represents the vertical direction. F b1z F represents the z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the first single-arm operating terminal position. b2z Let α be the z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the second single-arm operating terminal position, α be the real-time attitude angle of the hanging rod, D be the distance between the center of mass of the hanging rod and the nearest single-arm operating terminal, m be the mass of the hanging rod, and g be the acceleration due to gravity.

[0120] After establishing the mechanical model of the hanging pole, the mass and center of gravity of the hanging pole can be calculated based on the distance between the dual-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the dual-arm operating terminals. The calculation formula is as follows:

[0121]

[0122]

[0123] G = L + D

[0124] Where G is the position of the center of gravity of the hanging rod.

[0125] The position of the center of gravity G of the hanging pole, which is the distance L between the dual-arm operating terminals, is the position corresponding to the sum of the distance D between the center of gravity of the hanging pole and the nearest single-arm operating terminal.

[0126] The present invention provides a method for dynamically estimating the load of an exoskeleton's slingshot-operated terminal. It establishes a mechanical model of the exoskeleton's upper limbs to solve for the force exerted by the slingshot on the exoskeleton clamp at the position of the dual-arm operating terminal, which is beneficial for estimating the mechanical state of the exoskeleton's operating terminal. Based on the kinematic model of the exoskeleton's upper limbs, it calculates the position and distance of the dual-arm operating terminals, which is beneficial for determining the relative positional relationship between the two arms. Based on the distance between the dual-arm operating terminals, the force exerted by the slingshot on the exoskeleton clamp at the position of the dual-arm operating terminals, and the mechanical model of the slingshot, it calculates the mass and center of gravity of the slingshot, which is beneficial for selecting and determining the exoskeleton's control scheme. This method achieves accurate estimation of the weight and center of gravity of the load on the exoskeleton's slingshot-operated terminal, facilitating the perception and identification of the exoskeleton robot's usage status and improving control accuracy.

[0127] For easier understanding, please refer to Figure 5 This invention provides an embodiment of an exoskeleton pole operation terminal load dynamic estimation system, comprising:

[0128] The upper limb biomechanics solution module is used to establish the upper limb biomechanics model of the exoskeleton and solve the force exerted by the hanging rod at the end position of the two arms on the exoskeleton clamp.

[0129] The terminal distance calculation module is used to establish the kinematic model of the upper limb of the exoskeleton, analyze the relationship between the position of the dual-arm operating terminal and the joint angle based on the DH parameters, solve the position of the dual-arm operating terminal, and calculate the distance between the dual-arm operating terminals based on the position of the dual-arm operating terminals.

[0130] The pole information calculation module is used to establish a mechanical model of the pole. Based on the distance between the dual-arm operating terminals and the force exerted by the pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the pole are calculated.

[0131] The upper limb biomechanics solution module is specifically used for:

[0132] Obtain the angle, angular velocity, and angular acceleration information of each joint in the upper limb of the exoskeleton, and establish a mechanical model of the upper limb of the exoskeleton. The mechanical model of the upper limb of the exoskeleton is as follows:

[0133]

[0134] Where, τ d To maintain the joint torque for upper limb movement, M(θ) is the mass matrix, and θ is the angle at the joint. The angular acceleration at the joint. The angular velocity at the joint. G(θ) is the vector of centrifugal force and Coriolis force, and G(θ) is the vector of gravity.

[0135] Based on the force exerted on the exoskeleton's upper limb distal end during the wearer's operation, the mapped torque of the hand force at each joint position is calculated using the following formula:

[0136] τ h =J T F h

[0137] Where, τ h J is the mapped torque of the hand force at each joint position. T Let F be the transpose of the Jacobian matrix J. h The force applied to the extremities of the exoskeleton during the wearer's operation;

[0138] The output torque of the joint drive is calculated based on the feedback current obtained from each joint motor. The calculation formula is as follows:

[0139] τ m =k i n r im

[0140] Where, τ m k is the output torque of the joint drive. i Let n be the torque constant of the joint motor. r i is the reduction ratio of the reducer. m The feedback current obtained by the joint motor;

[0141] Based on the output torque of the joint drive, the mapped torque of the hand force at each joint position, and the joint torque maintaining upper limb movement, the mapped torque of the operating terminal rod pressure at each joint position is calculated using the following formula:

[0142] τ b =τ d -τ h -τ m

[0143] Where, τ b The mapped torque of the operating terminal arm pressure at each joint position;

[0144] The force exerted by the hanging rod on the exoskeleton at the dual-arm operating terminal position is calculated based on the mapped torque of the pressure on the hanging rod at each joint position. The formula for calculating the force exerted by the hanging rod on the exoskeleton at the dual-arm operating terminal position is as follows:

[0145]

[0146] Among them, F b The force exerted by the hanging rod at the single-arm operation terminal position on the exoskeleton clamp.

[0147] A kinematic model of the upper limbs of an exoskeleton was established. Based on the DH parameters, the relationship between the positions of the dual-arm manipulators and their joint angles was analyzed, and the positions of the dual-arm manipulators were determined, including:

[0148] Establish an exoskeleton upper limb kinematic model;

[0149] Based on the DH parameter analysis, the relationship between the position of the dual-arm operating terminal and the joint angle is obtained, and the coordinate rotation matrix of each arm is obtained.

[0150] Based on the coordinate rotation matrices of each arm, calculate the coordinate positions of the operating terminals of the two arms relative to the back frame.

[0151] The position of the dual-arm operating terminal is calculated based on its coordinate position relative to the back frame.

[0152] The formula for calculating the distance between the two-arm manipulator terminals based on their positions is as follows:

[0153] L = |Vb |=P h1 -P h2

[0154] Where L is the distance between the dual-arm operating terminals, and V b Let P be the spatial vector formed by the dual-arm operating terminals. h1 Let P be the coordinate position of the first single-arm operating terminal relative to the back frame. h2 The coordinates of the second single-arm operating terminal relative to the back frame.

[0155] The pole information calculation module is specifically used for:

[0156] Establish a mechanical model for the hanging rod. The mechanical model of the hanging rod is as follows:

[0157]

[0158] In the exoskeleton's joint coordinate system, the x-axis represents the projection of the extension direction of the hanging rod onto the horizontal plane, the y-axis represents the projection of the forearm extension direction onto the horizontal plane and perpendicular to the x-axis, and the z-axis represents the vertical direction. F b1z F represents the z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the first single-arm operating terminal position. b2z Let α be the z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the position of the second single-arm operating terminal, α be the real-time attitude angle of the hanging rod, D be the distance between the center of mass of the hanging rod and the nearest single-arm operating terminal, m be the mass of the hanging rod, and g be the acceleration due to gravity.

[0159] Based on the distance between the dual-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the hanging pole are calculated using the following formula:

[0160]

[0161]

[0162] G = L + D

[0163] Where G is the position of the center of gravity of the hanging rod.

[0164] The exoskeleton pole operation terminal load dynamic estimation system provided by this invention is used to execute the exoskeleton pole operation terminal load dynamic estimation method provided in this invention. Its principle and the technical effect achieved are the same as the exoskeleton pole operation terminal load dynamic estimation method provided in this invention, and will not be repeated here.

[0165] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for dynamically estimating the load of an exoskeleton pole operating terminal, characterized in that, include: A biomechanical model of the upper limbs of the exoskeleton was established, and the force exerted by the hanging rod at the end position of the two arms on the exoskeleton clamp was solved. A kinematic model of the upper limb of the exoskeleton was established. The relationship between the position of the dual-arm manipulator and the joint angle was analyzed based on the DH parameters, and the position of the dual-arm manipulator was solved. Calculate the distance between the two-arm operating terminals based on their positions. A mechanical model of the hanging pole is established. Based on the distance between the two-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the two-arm operating terminals, the mass and center of gravity of the hanging pole are calculated. A biomechanical model of the upper limbs of the exoskeleton was established, and the forces exerted by the hanging rods at the end positions of the two arms on the exoskeleton clamps were calculated, including: Obtain the angle, angular velocity, and angular acceleration information of each joint in the upper limb of the exoskeleton, and establish a mechanical model of the upper limb of the exoskeleton. The mechanical model of the upper limb of the exoskeleton is as follows: in, To maintain joint torque during upper limb movement, For the quality matrix, The angle at the joint. The angular acceleration at the joint. The angular velocity at the joint. The centrifugal force and Coriolis force are vectors. It is the gravity vector; Based on the force exerted on the exoskeleton's upper limb distal end during the wearer's operation, the mapped torque of the hand force at each joint position is calculated using the following formula: in, This represents the mapped torque of the hand force at each joint position. Let J be the transpose of the Jacobian matrix J. The force applied to the extremities of the exoskeleton during the wearer's operation; The output torque of the joint drive is calculated based on the feedback current obtained from each joint motor. The calculation formula is as follows: in, The output torque for joint drive, The torque constant of the joint motor. The reduction ratio of the reducer. The feedback current obtained by the joint motor; Based on the output torque of the joint drive, the mapped torque of the hand force at each joint position, and the joint torque maintaining upper limb movement, the mapped torque of the operating terminal rod pressure at each joint position is calculated using the following formula: in, The mapped torque of the operating terminal arm pressure at each joint position; The force exerted by the hanging rods at the dual-arm operating terminal positions on the exoskeleton clamp is calculated based on the mapped torque of the pressure on the hanging rods at each joint position. The formula for calculating the force exerted by the hanging rods on the exoskeleton clamp at the dual-arm operating terminal positions is as follows: in, The force exerted by the hanging rod at the single-arm operation terminal position on the exoskeleton clamp; A mechanical model of the hanging pole is established. Based on the distance between the dual-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the hanging pole are calculated, including: Establish a mechanical model for the hanging rod. The mechanical model of the hanging rod is as follows: In the exoskeleton's joint coordinate system, the x-axis represents the projection of the extension direction of the hanging rod onto the horizontal plane, the y-axis represents the projection of the forearm extension direction onto the horizontal plane and perpendicular to the x-axis, and the z-axis represents the vertical direction. The z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the first single-arm operating terminal position is given. The z-axis component represents the force exerted by the hanging rod on the exoskeleton clamp at the second single-arm operating terminal position. denoted as the real-time attitude angle of the pole, D as the distance between the pole's center of mass and the nearest single-arm operating terminal, m as the mass of the pole, and g as the acceleration due to gravity. Based on the distance between the dual-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the hanging pole are calculated using the following formula: G=L+D Where G is the position of the center of gravity of the hanging rod.

2. The method for dynamically estimating the load of the exoskeleton pole operation terminal according to claim 1, characterized in that, A kinematic model of the upper limbs of an exoskeleton was established. Based on the DH parameters, the relationship between the positions of the dual-arm manipulators and their joint angles was analyzed, and the positions of the dual-arm manipulators were determined, including: Establish an exoskeleton upper limb kinematic model; Based on the DH parameter analysis, the relationship between the position of the dual-arm operating terminal and the joint angle is obtained, and the coordinate rotation matrix of each arm is obtained. Based on the coordinate rotation matrices of each arm, calculate the coordinate positions of the operating terminals of the two arms relative to the back frame. The position of the dual-arm operating terminal is calculated based on its coordinate position relative to the back frame.

3. The method for dynamically estimating the load of the exoskeleton pole operation terminal according to claim 2, characterized in that, The formula for calculating the distance between the two-arm manipulator terminals based on their positions is as follows: Where L is the distance between the dual-arm operating terminals. The spatial vector formed by the dual-arm operating terminals. The coordinate position of the first single-arm operating terminal relative to the back frame. The coordinates of the second single-arm operating terminal relative to the back frame.

4. A dynamic load estimation system for an exoskeleton pole operating terminal, characterized in that, include: The upper limb biomechanics solution module is used to establish the upper limb biomechanics model of the exoskeleton and solve the force exerted by the hanging rod at the end position of the two arms on the exoskeleton clamp. The terminal distance calculation module is used to establish a kinematic model of the upper limbs of the exoskeleton, analyze the relationship between the position of the dual-arm operating terminal and the joint angle based on the DH parameters, solve for the position of the dual-arm operating terminal, and calculate the distance between the dual-arm operating terminals based on the position of the dual-arm operating terminal. The pole information calculation module is used to establish the mechanical model of the pole. Based on the distance between the dual-arm operating terminals and the force exerted by the pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the pole are calculated. The upper limb biomechanics solution module is specifically used for: Obtain the angle, angular velocity, and angular acceleration information of each joint in the upper limb of the exoskeleton, and establish a mechanical model of the upper limb of the exoskeleton. The mechanical model of the upper limb of the exoskeleton is as follows: in, To maintain joint torque during upper limb movement, For the quality matrix, The angle at the joint. The angular acceleration at the joint. The angular velocity at the joint. For the centrifugal force and Coriolis force vectors, It is the gravity vector; Based on the force exerted on the exoskeleton's upper limb distal end during the wearer's operation, the mapped torque of the hand force at each joint position is calculated using the following formula: in, This represents the mapped torque of the hand force at each joint position. Let J be the transpose of the Jacobian matrix J. The force applied to the extremities of the exoskeleton during the wearer's operation; The output torque of the joint drive is calculated based on the feedback current obtained from each joint motor. The calculation formula is as follows: in, The output torque for joint drive, The torque constant of the joint motor. The reduction ratio of the reducer. The feedback current obtained by the joint motor; Based on the output torque of the joint drive, the mapped torque of the hand force at each joint position, and the joint torque maintaining upper limb movement, the mapped torque of the operating terminal rod pressure at each joint position is calculated using the following formula: in, The mapped torque of the operating terminal arm pressure at each joint position; The force exerted by the hanging rods at the dual-arm operating terminal positions on the exoskeleton clamp is calculated based on the mapped torque of the pressure on the hanging rods at each joint position. The formula for calculating the force exerted by the hanging rods on the exoskeleton clamp at the dual-arm operating terminal positions is as follows: in, The force exerted by the hanging rod at the single-arm operation terminal position on the exoskeleton clamp; The pole information calculation module is specifically used for: Establish a mechanical model for the hanging rod. The mechanical model of the hanging rod is as follows: In the exoskeleton's joint coordinate system, the x-axis represents the projection of the extension direction of the hanging rod onto the horizontal plane, the y-axis represents the projection of the forearm extension direction onto the horizontal plane and perpendicular to the x-axis, and the z-axis represents the vertical direction. The z-axis component of the force exerted by the hanging rod on the exoskeleton clamp at the first single-arm operating terminal position is given. The z-axis component represents the force exerted by the hanging rod on the exoskeleton clamp at the second single-arm operating terminal position. denoted as the real-time attitude angle of the pole, D as the distance between the pole's center of mass and the nearest single-arm operating terminal, m as the mass of the pole, and g as the acceleration due to gravity. Based on the distance between the dual-arm operating terminals and the force exerted by the hanging pole on the exoskeleton clamp at the position of the dual-arm operating terminals, the mass and center of gravity of the hanging pole are calculated using the following formula: G=L+D Where G is the position of the center of gravity of the hanging rod.

5. The exoskeleton pole operation terminal load dynamic estimation system according to claim 4, characterized in that, A kinematic model of the upper limbs of an exoskeleton was established. Based on the DH parameters, the relationship between the positions of the dual-arm manipulators and their joint angles was analyzed, and the positions of the dual-arm manipulators were determined, including: Establish an exoskeleton upper limb kinematic model; Based on the DH parameter analysis, the relationship between the position of the dual-arm operating terminal and the joint angle is obtained, and the coordinate rotation matrix of each arm is obtained. Based on the coordinate rotation matrices of each arm, calculate the coordinate positions of the operating terminals of the two arms relative to the back frame. The position of the dual-arm operating terminal is calculated based on its coordinate position relative to the back frame.

6. The exoskeleton pole operation terminal load dynamic estimation system according to claim 5, characterized in that, The formula for calculating the distance between the two-arm manipulator terminals based on their positions is as follows: Where L is the distance between the dual-arm operating terminals. The spatial vector formed by the dual-arm operating terminals. The coordinate position of the first single-arm operating terminal relative to the back frame. The coordinates of the second single-arm operating terminal relative to the back frame.

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