Hydro-muscle model simulation method and device, electronic equipment and storage medium

Abstract

The application provides a liquid muscle model simulation method and device, electronic equipment and storage medium. The method comprises the following steps: obtaining detection parameters of a liquid muscle model to be simulated, the detection parameters comprising a resting length of an effective deformation part of the liquid muscle and a total length of a rope and an ineffective deformation part of the liquid muscle; determining a minimum relative length ratio of the liquid muscle that can be shortened and a maximum relative length ratio of the liquid muscle that can be stretched; calculating a lower limit of a tendon length of the liquid muscle and an upper limit of the tendon length according to the minimum relative length ratio, the maximum relative length ratio, the resting length and the total length; inputting the minimum relative length ratio, the maximum relative length ratio, the lower limit of the tendon length and the upper limit of the tendon length into a physical engine based on multi-body dynamics to obtain a liquid muscle simulation model of the liquid muscle model. The application can realize long muscle biomechanics simulation across multiple joints while reducing the training difficulty of a robot with a liquid muscle model.

Description

Technical Field

[0001] This application relates to the field of robot control technology, and in particular to a method, device, electronic device and storage medium for simulating a hydraulic muscle model. Background Technology

[0002] Existing models of hydraulic muscles mostly use a single medium for actuation, while pure hydraulic muscle systems have significant response delays, and the length of hydraulic muscles is difficult to span long joints or double joints like real human muscles.

[0003] In related technologies, the length of real human muscles is simulated by directly connecting hydraulic muscles to ropes. However, the direct connection between the ropes and muscles results in the rope length constantly changing while the muscle length remains constant, which does not match the actual situation of muscle movement, leading to low simulation accuracy. Furthermore, while adding connecting blocks between the muscles and ropes can solve the actuation problem, it increases the number of joint degrees of freedom during robot training, increasing the training workload and difficulty. Summary of the Invention

[0004] In view of this, this application provides a method, device, electronic device and storage medium for simulating a hydraulic muscle model, which can reduce the training difficulty of robots with hydraulic muscle models while realizing the biomechanical simulation of long muscles spanning multiple joints.

[0005] A first aspect of this application provides a method for simulating a hydraulic muscle model, comprising: acquiring detection parameters of a hydraulic muscle model to be simulated, wherein the hydraulic muscle model includes a hydraulic muscle and a rope, the hydraulic muscle and the rope being connected to simulate the length of a real human muscle, and the detection parameters including the resting length of the effective deformable portion of the hydraulic muscle, and the total length of the rope and the ineffective deformable portion of the hydraulic muscle; determining the minimum relative length ratio that the hydraulic muscle can be shortened and the maximum relative length ratio that it can be stretched; and, based on the minimum relative length ratio and the maximum relative length... The ratio, the resting length, and the total length are used to calculate the lower limit and upper limit of the tendon length of the hydrodynamic muscle. The minimum relative length ratio, the maximum relative length ratio, the lower limit of the tendon length, and the upper limit of the tendon length are input into a physics engine based on multibody dynamics to obtain a hydrodynamic muscle simulation model. The physics engine calculates the resting tendon length and the optimal resting length of the simulated hydrodynamic muscle in the hydrodynamic muscle simulation model based on the minimum relative length ratio, the maximum relative length ratio, the lower limit of the tendon length, and the upper limit of the tendon length.

[0006] In one possible implementation, calculating the lower limit and upper limit of the tendon length of the hydrodynamic muscle based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length includes: calculating the lower limit and upper limit of the tendon length according to the following formula: lengthrange[0] = L0 × range[0] + LT; lengthrange[1] = L0 × range[1] + LT; where lengthrange[0] is the lower limit of the tendon length, L0 is the resting length, LT is the total length, range[0] is the minimum relative length ratio, lengthrange[1] is the upper limit of the tendon length, and range[1] is the maximum relative length ratio.

[0007] In one possible implementation, determining the minimum relative length ratio that the fluid-moving muscle can shorten and the maximum relative length ratio that it can stretch includes: determining the minimum length that the fluid-moving muscle can shorten, and using the ratio of the minimum length to the resting length as the minimum relative length ratio; determining the maximum length that the fluid-moving muscle can stretch, and using the ratio of the maximum length to the resting length as the maximum relative length ratio.

[0008] In one possible implementation, the detection parameters further include a first time required for the muscle to transition from relaxation to maximum contraction, a second time required for the muscle to recover from a contracted state to a relaxed state, and the maximum contractile force of the muscle; before inputting the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into the multibody dynamics-based physics engine, the method further includes: establishing a multibody dynamics behavior feature expression for the simulated tendon of the simulated hydrodynamic muscle based on the first time, the second time, and the maximum contractile force of the muscle; inputting the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into the multibody dynamics-based physics engine includes: inputting the multibody dynamics behavior feature expression, the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into the physics engine.

[0009] In one possible implementation, the multibody dynamics behavior feature expression includes a first feature expression of the simulated tendon during the contraction phase and a second feature expression of the simulated tendon during the relaxation phase; establishing the multibody dynamics behavior feature expression of the simulated tendon based on the first time, the second time, and the maximum muscle contraction force includes setting the following formula as the first feature expression: F1(t) = force × activation(t) × (1 - e^(-t1 / timeconst_contract)), where F1(t) is the contractile force of the simulated tendon during the contraction phase, force is the maximum contractile force of the muscle, t1 is the actual contraction time of the simulated tendon, and timeconst_contract is the first time; the following formula is set as the second characteristic expression: F2(t) = force × activation(t) × (1 - e^(-t2 / timeconst_relax)), where F2(t) is the relaxation tension of the simulated tendon during the relaxation phase, force is the maximum contractile force of the muscle, t2 is the actual relaxation time of the simulated tendon, and timeconst_relax is the second time.

[0010] In one possible implementation, the physics engine is the MuJoCo physics engine.

[0011] In one possible implementation, the material of the hydrodynamic muscle model includes rubber, and the detection parameters further include the nonlinear damping coefficient and stiffness coefficient of the rubber; the step of inputting the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into a multibody dynamics-based physics engine includes: inputting the nonlinear damping coefficient, the stiffness coefficient, the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into the multibody dynamics-based physics engine.

[0012] Secondly, embodiments of this application also provide a simulation device for a hydraulic muscle model, comprising: an acquisition module, a determination module, a calculation module, and an input module; the acquisition module is used to acquire detection parameters of the hydraulic muscle model to be simulated, wherein the hydraulic muscle model includes hydraulic muscles and ropes, the hydraulic muscles and the ropes are connected to simulate the length of real human muscles, and the detection parameters include the resting length of the effective deformable portion of the hydraulic muscles, and the total length of the ropes and the ineffective deformable portion of the hydraulic muscles; the determination module is used to determine the minimum relative length ratio that the hydraulic muscles can shorten and the maximum relative length ratio that they can stretch; the calculation module is used to calculate based on... The minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length are used to calculate the lower limit and upper limit of the tendon length of the hydrodynamic muscle. The input module is used to input the minimum relative length ratio, the maximum relative length ratio, the lower limit of the tendon length, and the upper limit of the tendon length into a physics engine based on multibody dynamics to obtain a hydrodynamic muscle simulation model. The physics engine calculates the resting tendon length and the optimal resting muscle length of the simulated hydrodynamic muscle in the hydrodynamic muscle simulation model based on the minimum relative length ratio, the maximum relative length ratio, the lower limit of the tendon length, and the upper limit of the tendon length.

[0013] Thirdly, embodiments of this application also provide an electronic device, the electronic device including a processor and a memory, the memory being used to store instructions, and the processor being used to call the instructions in the memory, causing the electronic device to execute the hydraulic muscle model simulation method as described in the first aspect.

[0014] Fourthly, embodiments of this application also provide a computer-readable storage medium that stores computer instructions that, when executed on an electronic device, cause the electronic device to perform the hydraulic muscle model simulation method as described in the first aspect.

[0015] Compared with related technologies, the embodiments of this application have at least the following advantages: Since the hydraulic muscle model includes hydraulic muscles and rope connections to simulate the length of real human muscles, it achieves biomechanical simulation of long muscles spanning multiple joints, avoiding the situation where "the length of hydraulic muscles is difficult to span long joints or double joints like real human muscles, resulting in low simulation accuracy," thus improving the simulation accuracy of the hydraulic muscle simulation model; since the detection parameters include the resting length of the effective deformable portion of the hydraulic muscle and the total length of the rope and the ineffective deformable portion of the hydraulic muscle, after determining the minimum relative length ratio that the hydraulic muscle can shorten and the maximum relative length ratio that it can stretch, the hydraulic muscle can be calculated based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length. The lower and upper limits of tendon length for the kinetic muscle are determined, and then the minimum and maximum relative length ratios, the lower and upper limits of tendon length are input into a multibody dynamics-based physics engine. This allows the physics engine to calculate the resting tendon length and optimal resting muscle length of the simulated kinetic muscle in the kinetic muscle simulation model. The total length of the ineffective deformation portion of the rope and kinetic muscle is defined as the resting tendon length, and the resting length of the effective deformation portion of the kinetic muscle is defined as the optimal resting muscle length. By equivalent substitution, the lengths of the rope and kinetic muscle are perfectly incorporated into a single tendon, thus achieving composite actuation of the kinetic muscle and rope. This reduces the number of joint degrees of freedom during robot training with a kinetic muscle model, thereby reducing the difficulty of robot training.

[0016] The technical effects achieved by the second, third, and fourth aspects mentioned above are similar to those achieved by the corresponding technical means in the first aspect, and will not be repeated here. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating one step of a simulation method for a hydraulic muscle model provided in an embodiment of this application.

[0018] Figure 2 Another flowchart of the simulation method for a hydraulic muscle model provided in an embodiment of this application.

[0019] Figure 3 This is a functional block diagram of a hydraulic muscle model simulation device provided in an embodiment of this application.

[0020] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0021] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0022] The following description sets forth many specific details to provide a full understanding of this application. The described embodiments are only some, not all, of the embodiments of this application.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0024] It should be further noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0025] In this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and drawings of this application are used to distinguish similar objects, not to describe a specific order or sequence.

[0026] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0027] For ease of understanding, some concepts related to the embodiments of this application are illustrated and explained by way of example for reference.

[0028] MuJoCo Physics Engine: A high-performance physics engine focused on robotics, biomechanics, and machine learning. Its core design integrates innovative technologies from dynamics simulation and contact mechanics. It pioneered the combination of generalized coordinates from robotics with modern contact dynamics optimization methods, solving soft contact constraints through convex optimization. This avoids the instability of traditional spring-damped models, significantly improving the accuracy and stability of simulations of complex joint systems. It supports tendon modeling (3D path constraints, entanglement simulation) and general actuator models (unified modeling of motors / hydraulics / biological muscles), meeting diverse physical interaction needs.

[0029] The Muscle Hill Model: A core theoretical framework in biophysics and muscle mechanics, used to describe the mechanical properties and molecular synergistic effects of muscle contraction. By distinguishing between active contraction and passive elastic components, the Muscle Hill Model reveals the mechanism of muscle force generation. Its three-component structure provides a fundamental framework for modern musculoskeletal dynamics research and, together with the Adair equation, constitutes a complementary theoretical tool for synergistic effect analysis.

[0030] Hydraulic muscle: This is a soft actuator that uses hydraulic or pneumatic pressure to drive flexible materials, simulating the contraction of biological muscles. Its core principle is to use fluid pressure to deform an elastic structure and generate mechanical motion. It consists of an elastic inner liner (rubber / silicone) and a braided sleeve. After fluid is injected, the internal pressure increases, and the sleeve's constraint causes axial contraction and outputs tensile force. The deformation rate can reach 20%-30%.

[0031] Muscle actuators: These are biomimetic actuators that mimic the contraction and relaxation mechanisms of biological muscles. They are mainly divided into two major directions: biological muscle drive principles and artificial muscle technology. The core goal is to provide robots, medical devices, and other devices with compliant and efficient power output that is close to that of biological muscles.

[0032] Please refer to Figure 1 , Figure 1 This is a flowchart illustrating the steps of an embodiment of the hydraulic muscle model simulation method of this application. Depending on different requirements, the order of the steps in this flowchart can be changed, and some steps can be omitted.

[0033] It should be noted that the hydraulic muscle model simulation method of this application embodiment can be applied to robot simulation scenarios, and its execution subject can be a hydraulic muscle model simulation device. For example, in a robot simulation scenario, the simulation of a robot can be achieved through a hydraulic muscle model simulation device. Of course, the hydraulic muscle model simulation method can also be applied to other scenarios that require robot simulation, and this application does not specifically limit it in this regard.

[0034] The specific process of this embodiment is as follows: Figure 1 As shown, it includes the following steps: S101, Obtain the detection parameters of the hydraulic muscle model to be simulated. The hydraulic muscle model includes hydraulic muscles and ropes. The hydraulic muscles and ropes are connected to simulate the length of real human muscles. The detection parameters include the resting length of the effective deformable part of the hydraulic muscle and the total length of the ropes and the ineffective deformable part of the hydraulic muscle.

[0035] In some embodiments, the material of the hydrodynamic muscle model includes rubber, and the detection parameters also include the nonlinear damping coefficient and stiffness coefficient of the rubber.

[0036] In some embodiments, a physical hydraulic muscle model is established using rubber and ropes, and then the hydraulic muscle model is tested to obtain test parameters.

[0037] S102, determine the minimum relative length ratio that the hydrodynamic muscle can shorten and the maximum relative length ratio that it can stretch.

[0038] In some embodiments, the minimum relative length ratio and the maximum relative length ratio can be determined as follows: the minimum length that the hydrodynamic muscle can shorten is determined, and the ratio of the minimum length to the resting length is taken as the minimum relative length ratio; the maximum length that the hydrodynamic muscle can stretch is determined, and the ratio of the maximum length to the resting length is taken as the maximum relative length ratio.

[0039] Specifically, there is a limit to the actual contraction of a fluid-driven muscle. For example, if the maximum degree of contraction is 75% of the resting state, then the minimum relative length ratio is 0.75. Similarly, there is a limit to the actual contraction of a fluid-driven muscle. For example, if the maximum degree of stretching is 110% of the resting state, then the maximum relative length ratio is 1.1.

[0040] S103, calculate the lower limit and upper limit of tendon length of hydrodynamic muscle based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length.

[0041] In some embodiments, the lower limit and upper limit of tendon length are calculated according to the following formula: lengthrange[0]=L0×range[0]+LT; lengthrange[1]=L0×range[1]+LT; Where lengthrange[0] is the lower limit of tendon length, L0 is the resting length, LT is the total length, range[0] is the minimum relative length ratio, lengthrange[1] is the upper limit of tendon length, and range[1] is the maximum relative length ratio.

[0042] S104. Input the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into the physics engine based on multibody dynamics to obtain the hydrodynamic muscle simulation model.

[0043] Specifically, the physics engine calculates the resting tendon length and optimal resting muscle length of the simulated hydrodynamic muscle in the hydrodynamic muscle simulation model based on the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length.

[0044] In some embodiments, the physics engine is the MuJoCo physics engine. Specifically, in the MuJoCo physics engine, the muscle actuator is a composite actuator formed by connecting muscles and tendons in series. Tendon (tendon length) = biological (muscle + tendon) length. It can be deduced that the biological tendon length remains unchanged, the biological muscle is the part that generates driving force, and the tendon is composed of these two parts, so they can be equivalently separated and replaced.

[0045] The Hill model of muscle contains several key constants: tendon resting length (LT): assuming the biological tendon is inelastic and of constant length; optimal resting length of muscle (L0): the length at which the muscle generates maximum static active force. Based on these constants, the hydraulic muscle and the connecting rope are considered as a single, extremely long muscle, with the rope representing the biological tendon portion and the hydraulic muscle representing the biological muscle portion. Therefore, the rope length (measured on a real machine) and the length of the non-deformable portion of the hydraulic muscle are added together, and this sum is assigned to LT to make it equivalent to a biological tendon of constant length. The initial effective deformation length of the hydraulic muscle is assigned to L0.

[0046] After the physics engine calculates the tendon resting length LT and the optimal resting length L0 of the muscle, the total length of the ineffective deformation portion of the rope and the hydrodynamic muscle is defined as the tendon resting length LT, and the resting length of the effective deformation portion of the hydrodynamic muscle is defined as the optimal resting length L0 of the muscle. By equivalent substitution, the lengths of the rope and the hydrodynamic muscle are perfectly incorporated into a single tendon, thereby achieving the composite drive of the hydrodynamic muscle and the rope.

[0047] It should also be noted that, as described above, the material of the hydraulic muscle model includes rubber, and the detection parameters also include the nonlinear damping coefficient and stiffness coefficient of the rubber. Since rubber itself is a hyperelastic material, considering its anisotropic deformation would greatly increase the computational load and speed. Nonlinear damping coefficient and stiffness coefficient are more suitable for dynamic simulation. Therefore, inputting the nonlinear damping coefficient and stiffness coefficient into a physics engine based on multibody dynamics can improve the computational efficiency of the physics engine, thereby reducing the modeling complexity of the hydraulic muscle simulation model and enabling the hydraulic muscle simulation model to better simulate the effect of muscle contraction pulling the joint.

[0048] Compared with related technologies, the embodiments of this application have at least the following advantages: Since the hydraulic muscle model includes hydraulic muscles and rope connections to simulate the length of real human muscles, it achieves biomechanical simulation of long muscles spanning multiple joints, avoiding the situation where "the length of hydraulic muscles is difficult to span long joints or double joints like real human muscles, resulting in low simulation accuracy," thus improving the simulation accuracy of the hydraulic muscle simulation model; since the detection parameters include the resting length of the effective deformable portion of the hydraulic muscle and the total length of the rope and the ineffective deformable portion of the hydraulic muscle, after determining the minimum relative length ratio that the hydraulic muscle can shorten and the maximum relative length ratio that it can stretch, the hydraulic muscle can be calculated based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length. The lower and upper limits of tendon length for the kinetic muscle are determined, and then the minimum and maximum relative length ratios, the lower and upper limits of tendon length are input into a multibody dynamics-based physics engine. This allows the physics engine to calculate the resting tendon length and optimal resting muscle length of the simulated kinetic muscle in the kinetic muscle simulation model. The total length of the ineffective deformation portion of the rope and kinetic muscle is defined as the resting tendon length, and the resting length of the effective deformation portion of the kinetic muscle is defined as the optimal resting muscle length. By equivalent substitution, the lengths of the rope and kinetic muscle are perfectly incorporated into a single tendon, thus achieving composite actuation of the kinetic muscle and rope. This reduces the number of joint degrees of freedom during robot training with a kinetic muscle model, thereby reducing the difficulty of robot training.

[0049] This embodiment is a further improvement on the aforementioned embodiment. The main improvement lies in that: in this embodiment, the detection parameters also include the first time required for the muscle to go from relaxation to maximum contraction, the second time required for the muscle to recover from a contracted state to a relaxed state, and the maximum contractile force of the muscle. Furthermore, a multi-body dynamic behavior characteristic expression of the simulated tendon is input into the physics engine. This multi-body dynamic behavior characteristic expression is established based on the first time, the second time, and the maximum contractile force of the muscle. This approach further improves the simulation accuracy of the hydraulic muscle simulation model.

[0050] The specific process of this embodiment is as follows: Figure 2 As shown, it includes the following steps: S201, Obtain the detection parameters of the hydraulic muscle model to be simulated. The hydraulic muscle model includes hydraulic muscles and ropes, which are connected to simulate the length of real human muscles. The detection parameters include the resting length of the effective deformable part of the hydraulic muscle and the total length of the ropes and the ineffective deformable part of the hydraulic muscle.

[0051] S202, determine the minimum relative length ratio that the hydrodynamic muscle can shorten and the maximum relative length ratio that it can stretch.

[0052] S203, calculate the lower limit and upper limit of tendon length of hydrodynamic muscle based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length.

[0053] S204, establishes a multibody dynamic behavior characteristic expression for the simulated tendon based on the first time, the second time, and the maximum muscle contraction force.

[0054] In some embodiments, the multibody dynamics behavior characteristic expression includes a first characteristic expression of the simulated tendon during the contraction phase and a second characteristic expression of the simulated tendon during the relaxation phase.

[0055] In some embodiments, the following formula is set as the first characteristic expression: F1(t) = force × activation(t) × (1 - e^(-t1 / timeconst_contract)), where F1(t) is the contractile force of the simulated tendon during the contraction phase, force is the maximum contractile force of the muscle, t1 is the actual contraction time of the simulated tendon, and timeconst_contract is the first time. Set the following formula as the second characteristic expression: F2(t) = force × activation(t) × (1 - e^(-t2 / timeconst_relax)), where F2(t) is the relaxation tension of the simulated tendon during the relaxation phase, force is the maximum contractile force of the muscle, t2 is the actual relaxation time of the simulated tendon, and timeconst_relax is the second time.

[0056] It is worth noting that by establishing the first and second characteristic expressions, the asymmetric response characteristics of the hydraulic muscle can be physically represented, with contraction being faster than relaxation, thus enabling the hydraulic muscle simulation model to better reproduce the real situation of the hydraulic muscle.

[0057] S205: Input the multibody dynamics behavior characteristic expression, minimum relative length ratio, maximum relative length ratio, lower limit of tendon length, and upper limit of tendon length into the physics engine to obtain the hydrodynamic muscle simulation model.

[0058] Compared with related technologies, the embodiments of this application have at least the following advantages: Since the hydraulic muscle model includes hydraulic muscles and rope connections to simulate the length of real human muscles, it achieves biomechanical simulation of long muscles spanning multiple joints, avoiding the situation where "the length of hydraulic muscles is difficult to span long joints or double joints like real human muscles, resulting in low simulation accuracy," thus improving the simulation accuracy of the hydraulic muscle simulation model; since the detection parameters include the resting length of the effective deformable portion of the hydraulic muscle and the total length of the rope and the ineffective deformable portion of the hydraulic muscle, after determining the minimum relative length ratio that the hydraulic muscle can shorten and the maximum relative length ratio that it can stretch, the hydraulic muscle can be calculated based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length. The lower and upper limits of tendon length for the kinetic muscle are determined, and then the minimum and maximum relative length ratios, the lower and upper limits of tendon length are input into a multibody dynamics-based physics engine. This allows the physics engine to calculate the resting tendon length and optimal resting muscle length of the simulated kinetic muscle in the kinetic muscle simulation model. The total length of the ineffective deformation portion of the rope and kinetic muscle is defined as the resting tendon length, and the resting length of the effective deformation portion of the kinetic muscle is defined as the optimal resting muscle length. By equivalent substitution, the lengths of the rope and kinetic muscle are perfectly incorporated into a single tendon, thus achieving composite actuation of the kinetic muscle and rope. This reduces the number of joint degrees of freedom during robot training with a kinetic muscle model, thereby reducing the difficulty of robot training.

[0059] Based on the same idea as the hydraulic muscle model simulation method in the above embodiments, this application also provides a hydraulic muscle model simulation device, which can be used to execute the above-described hydraulic muscle model simulation method. For ease of explanation, the structural schematic diagram of the hydraulic muscle model simulation device embodiment only shows the parts related to the embodiments of this application. Those skilled in the art will understand that the illustrated structure does not constitute a limitation on the device, and it may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0060] like Figure 3 As shown, the hydraulic muscle model simulation device 30 includes an acquisition module 301, a determination module 302, a calculation module 303, and an input module 304. In some embodiments, the above modules can be programmable software instructions stored in memory and executable by a processor. It is understood that in other embodiments, the above modules can also be program instructions or firmware embedded in the processor.

[0061] The acquisition module 301 is used to acquire the detection parameters of the hydraulic muscle model to be simulated. The hydraulic muscle model includes a hydraulic muscle and a rope. The hydraulic muscle and the rope are connected to simulate the length of real human muscles. The detection parameters include the resting length of the effective deformable part of the hydraulic muscle and the total length of the rope and the ineffective deformable part of the hydraulic muscle. The determining module 302 is used to determine the minimum relative length ratio that the hydraulic muscle can shorten and the maximum relative length ratio that it can stretch; Calculation module 303 is used to calculate the lower limit and upper limit of tendon length of the hydrodynamic muscle based on the minimum relative length ratio, the maximum relative length ratio, the resting length and the total length; Input module 304 is used to input the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into a physics engine based on multibody dynamics to obtain a physics simulation model of the physics muscle model. The physics engine calculates the resting tendon length and the optimal resting muscle length of the simulated physics muscle in the physics simulation model based on the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length.

[0062] The hydraulic muscle model simulation device 30 provided in the above embodiments can realize the technical solutions described in the above hydraulic muscle model simulation method embodiments. The specific implementation principles of each module or unit can be found in the corresponding content in the above hydraulic muscle model simulation method embodiments, and will not be repeated here.

[0063] Please refer to Figure 4 , Figure 4 This is a schematic diagram of an embodiment of the electronic device of this application.

[0064] In some embodiments, processor 401 may be a central processing unit (CPU), microprocessor, or other data processing chip, used to run program code stored in memory 402 or process data, such as the hydraulic muscle model simulation method of the present invention.

[0065] In some embodiments, processor 401 may be a single server or a group of servers. The server group may be centralized or distributed. In some embodiments, processor 401 may be local or remote. In some embodiments, processor 401 may be implemented on a cloud platform. In one embodiment, the cloud platform may include a private cloud, public cloud, hybrid cloud, community cloud, distributed cloud, intranet, multi-cloud, etc., or any combination thereof.

[0066] In some embodiments, memory 402 may be an internal storage unit of electronic device 400, such as a hard disk or memory of electronic device 400. In other embodiments, memory 402 may also be an external storage device of electronic device 400, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc. equipped on electronic device 400.

[0067] Furthermore, the memory 402 may include both internal storage units of the electronic device 400 and external storage devices. The memory 402 is used to store application software and various types of data installed on the electronic device 400.

[0068] In some embodiments, display 403 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an OLED (Organic Light-Emitting Diode) touchscreen. Display 403 is used to display information from electronic device 400 and to display a visual user interface. Components 401-403 of electronic device 400 communicate with each other via a system bus.

[0069] In one embodiment, when the processor 401 executes the hydraulic muscle model simulation program in the memory 402, the following steps can be implemented: The detection parameters of the hydraulic muscle model to be simulated are obtained, wherein the hydraulic muscle model includes a hydraulic muscle and a rope, the hydraulic muscle and the rope are connected to simulate the length of real human muscles, and the detection parameters include the resting length of the effective deformable part of the hydraulic muscle, and the total length of the rope and the ineffective deformable part of the hydraulic muscle. Determine the minimum relative length ratio that the hydrodynamic muscle can shorten and the maximum relative length ratio that it can stretch; The lower limit and upper limit of the tendon length of the hydrodynamic muscle are calculated based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length. The minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length are input into a physics engine based on multibody dynamics to obtain a physics simulation model of the physics muscle model. The physics engine calculates the resting tendon length and the optimal resting muscle length of the simulated physics muscle in the physics simulation model based on the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length.

[0070] It should be understood that when the processor 401 executes the hydraulic muscle model simulation program in the memory 402, in addition to the functions mentioned above, it can also perform other functions, as detailed in the description of the corresponding method embodiments above.

[0071] Furthermore, this embodiment of the invention does not specifically limit the type of electronic device 400 mentioned. Electronic device 400 can be a mobile phone, tablet computer, personal digital assistant (PDA), wearable device, laptop computer, or other portable electronic device. Exemplary embodiments of portable electronic devices include, but are not limited to, portable electronic devices running iOS, Android, Microsoft, or other operating systems. The aforementioned portable electronic device can also be other portable electronic devices, such as a laptop computer with a touch-sensitive surface (e.g., a touch panel). It should also be understood that in some other embodiments of the invention, electronic device 400 may not be a portable electronic device, but rather a desktop computer with a touch-sensitive surface (e.g., a touch panel).

[0072] Accordingly, this application also provides a computer-readable storage medium for storing computer-readable programs or instructions. When the programs or instructions are executed by a processor, they can implement the steps or functions in the hydraulic muscle model simulation methods provided in the above-described method embodiments.

[0073] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware (such as a processor, controller, etc.), and the computer program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0074] The above provides a detailed description of the hydraulic muscle model simulation method, device, electronic equipment, and storage medium provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A simulation method for a hydraulic muscle model, characterized in that, include: The detection parameters of the hydraulic muscle model to be simulated are obtained, wherein the hydraulic muscle model includes a hydraulic muscle and a rope, the hydraulic muscle and the rope are connected to simulate the length of real human muscles, and the detection parameters include the resting length of the effective deformable part of the hydraulic muscle, and the total length of the rope and the ineffective deformable part of the hydraulic muscle. Determine the minimum relative length ratio that the hydrodynamic muscle can shorten and the maximum relative length ratio that it can stretch; The lower limit and upper limit of the tendon length of the hydrodynamic muscle are calculated based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length. The minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length are input into a physics engine based on multibody dynamics to obtain a physics simulation model of the physics muscle model. The physics engine calculates the resting tendon length and the optimal resting muscle length of the simulated physics muscle in the physics simulation model based on the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length.

2. The simulation method for a hydraulic muscle model according to claim 1, characterized in that, The calculation of the lower limit and upper limit of the tendon length of the hydrodynamic muscle based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length includes: The lower limit and upper limit of the tendon length are calculated using the following formulas: lengthrange[0]=L0×range[0]+LT; lengthrange[1]=L0×range[1]+LT; Wherein, lengthrange[0] is the lower limit of the tendon length, L0 is the resting length, LT is the total length, range[0] is the minimum relative length ratio, lengthrange[1] is the upper limit of the tendon length, and range[1] is the maximum relative length ratio.

3. The simulation method for a hydraulic muscle model according to claim 1 or 2, characterized in that, Determining the minimum relative length ratio that the hydrodynamic muscle can shorten and the maximum relative length ratio that it can stretch includes: Determine the minimum length that the hydrodynamic muscle can shorten, and use the ratio of the minimum length to the resting length as the minimum relative length ratio; The maximum stretchable length of the hydrodynamic muscle is determined, and the ratio of the maximum length to the resting length is taken as the maximum relative length ratio.

4. The simulation method for a hydraulic muscle model according to claim 1, characterized in that, The detection parameters also include the first time required for the muscle to go from relaxed to maximum contraction, the second time required for the muscle to recover from a contracted state to a relaxed state, and the maximum contractile force of the muscle. Before inputting the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into the multibody dynamics-based physics engine, the following steps are also included: Based on the first time, the second time, and the maximum contractile force of the muscle, establish a multibody dynamic behavior characteristic expression for the simulated tendon of the simulated hydraulic muscle; The step of inputting the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into a multibody dynamics-based physics engine includes: The multibody dynamics behavior characteristic expression, the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length are input into the physics engine.

5. The simulation method for a hydraulic muscle model according to claim 4, characterized in that, The multibody dynamics behavior characteristic expression includes a first characteristic expression of the simulated tendon during the contraction phase and a second characteristic expression of the simulated tendon during the relaxation phase. The step of establishing a multibody dynamic behavior characteristic expression for the simulated tendon based on the first time, the second time, and the maximum muscle contraction force includes: Set the following formula as the first characteristic expression: F1(t) = force × activation(t) × (1 - e^(-t1 / timeconst_contract)), where F1(t) is the contractile force of the simulated tendon during the contraction phase, force is the maximum contractile force of the muscle, t1 is the actual contraction time of the simulated tendon, and timeconst_contract is the first time. Set the following formula as the second characteristic expression: F2(t) = force × activation(t) × (1 - e^(-t2 / timeconst_relax)), where F2(t) is the relaxation tension of the simulated tendon during the relaxation phase, force is the maximum contractile force of the muscle, t2 is the actual relaxation time of the simulated tendon, and timeconst_relax is the second time.

6. The simulation method for a hydraulic muscle model according to claim 1, characterized in that, The physics engine is the MuJoCo physics engine.

7. The simulation method for a hydraulic muscle model according to claim 1, characterized in that, The material of the hydrodynamic muscle model includes rubber, and the detection parameters also include the nonlinear damping coefficient and stiffness coefficient of the rubber. The step of inputting the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into a multibody dynamics-based physics engine includes: The nonlinear damping coefficient, the stiffness coefficient, the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length are input into a physics engine based on multibody dynamics.

8. A hydraulic muscle model simulation device, characterized in that, include: The module includes an acquisition module, a determination module, a calculation module, and an input module. The acquisition module is used to acquire the detection parameters of the hydraulic muscle model to be simulated. The hydraulic muscle model includes a hydraulic muscle and a rope. The hydraulic muscle and the rope are connected to simulate the length of real human muscles. The detection parameters include the resting length of the effective deformable part of the hydraulic muscle and the total length of the rope and the ineffective deformable part of the hydraulic muscle. The determining module is used to determine the minimum relative length ratio that the hydraulic muscle can shorten and the maximum relative length ratio that it can stretch; The calculation module is used to calculate the lower limit and upper limit of the tendon length of the hydrodynamic muscle based on the minimum relative length ratio, the maximum relative length ratio, the resting length, and the total length. The input module is used to input the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length into a physics engine based on multibody dynamics to obtain a physics simulation model of the physics muscle model. The physics engine calculates the resting tendon length and the optimal resting muscle length of the simulated physics muscle in the physics simulation model based on the minimum relative length ratio, the maximum relative length ratio, the lower limit of tendon length, and the upper limit of tendon length.

9. An electronic device, the electronic device comprising a processor and a memory, characterized in that, The memory is used to store instructions, and the processor is used to call the instructions in the memory to cause the electronic device to execute the hydraulic muscle model simulation method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed on an electronic device, cause the electronic device to perform the hydraulic muscle model simulation method as described in any one of claims 1 to 7.

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