Rope-shaped sensor for measuring driving force of artificial muscle, preparation method and application

Abstract

The invention discloses a rope-shaped sensor for measuring driving force of artificial muscles, a preparation method and application. The rope-shaped sensor comprises a supporting tube (101), a sensing layer (102) and a conductive layer (104), a sensing layer (102) is arranged on the outer surface of the supporting tube (101); a conductive layer (104) is arranged on the outer surface of the sensing layer (102); the supporting pipe (101) plays a role in fixing; and the sensing layer (102) is used for detecting pressure and outputting a resistance value.

Description

Technical Field

[0001] The present invention relates to the technical field of robot sensors, and in particular to a rope-shaped sensor for measuring artificial muscle driving force, a preparation method and an application thereof. Background Art

[0002] Soft robotics and artificial muscle technologies have developed rapidly in recent years and have attracted much attention due to their ability to safely interact with the environment and the human body. These systems are usually made of flexible materials such as silicone rubber and fabrics, and have excellent flexibility and deformation capabilities. They are widely used in bionics, medical devices, wearable technology and special fields. However, the complex deformation characteristics of soft materials pose challenges to real-time monitoring of shape and position.

[0003] Traditional rigid sensors usually affect the flexibility of soft robots due to their size and rigidity. Flexible sensors based on electrospinning technology and functional nanomaterials have shown excellent mechanical and temperature stability, providing a new solution for real-time monitoring of soft robots and artificial muscles. However, there is still a lack of efficient and reliable sensors for the precise measurement of artificial muscle driving force.

[0004] A Chinese patent (CN118836763A) discloses a process for directly preparing a tensile strain sensor on a soft robot and its application in an inverse artificial muscle soft actuator, wherein the tensile strain sensor is directly prepared on the artificial muscle, and its sensing layer will deform with the deformation of the artificial muscle, which requires the artificial muscle to allocate a part of the driving force to deform the sensing layer, resulting in the problem of inaccurate measurement of the driving force of the artificial muscle, especially for artificial muscles with smaller driving force, so the versatility is not high. Summary of the invention

[0005] In view of the problem of inaccurate measurement of artificial muscle driving force in the prior art, the present invention proposes a rope-shaped sensor for measuring artificial muscle driving force, a preparation method, and an application.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A rope-shaped sensor for measuring artificial muscle driving force, comprising a support tube 101, a sensing layer 102 and a conductive layer 104;

[0008] The outer surface of the support tube 101 is provided with a sensing layer 102; the outer surface of the sensing layer 102 is provided with a conductive layer 104;

[0009] The support tube 101 plays a role of fixed support; the sensing layer 102 is used to detect pressure and output resistance value; the conductive layer 104 is used to apply pressure to the sensing layer 102 when subjected to external force and to connect an external measuring device.

[0010] Preferably, the support tube 101 is a capillary tube.

[0011] Preferably, the sensing layer 102 is located at the middle end of the support tube 101 .

[0012] Preferably, the density of the support tube 101 is greater than the density of the conductive layer 104 .

[0013] The present invention also provides a preparation method for preparing a rope-shaped sensor for measuring artificial muscle driving force, which specifically comprises the following steps:

[0014] S1: Select a capillary tube as the support tube 101;

[0015] S2: preparing a sensing layer 102 at the middle end of the support tube 101;

[0016] S3: preparing a conductive layer 104 on the outer surface of the sensing layer 102 .

[0017] Preferably, the S2 includes:

[0018] S2-1: adding carbon black powder into dimethyl sulfoxide solvent to prepare a 0.5% carbon slurry solution;

[0019] S2-2: dissolving soluble plastic particles in dimethyl sulfoxide solvent to form a plastic solution;

[0020] S2-3: adding the carbon slurry solution to the plastic solution to obtain a mixed solution;

[0021] S2-4: using an electrospinning device to prepare the mixed solution into conductive fiber filaments;

[0022] S2-5: Weaving the conductive fiber filaments at the middle end of the support tube 101 to form the sensing layer 102.

[0023] Preferably, in S2-1, the method for preparing the carbon slurry solution comprises:

[0024] After adding carbon black powder into dimethyl sulfoxide solvent, stirring is performed for half an hour using a magnetic stirrer to obtain a first solution;

[0025] Then the first solution is transferred to an ultrasonic cleaning apparatus and subjected to ultrasonic treatment to obtain a second solution;

[0026] The second solution is then stirred using a magnetic stirrer to obtain a carbon slurry solution.

[0027] Preferably, in S2-5, the preparation method of the sensing layer 102 is:

[0028] First, ten conductive fiber threads are combined into a conductive fiber bundle, and then a weaving machine is used to weave the conductive fiber bundle into a conductive fiber rope skin, namely the sensing layer 102, at the middle end of the support tube 101.

[0029] Preferably, S3 includes:

[0030] S3-1: using an electrospinning device to prepare a plastic solution into insulating fiber filaments; then synthesizing thirty conductive fiber filaments into a conductive fiber bundle 103, and synthesizing thirty insulating fiber filaments into an insulating fiber bundle 105;

[0031] S3-2: Using a weaving machine, weave ten insulating fiber bundles 105 and two conductive fiber bundles 103 onto the outer surface of the sensing layer 102 to obtain a conductive layer 104 .

[0032] The present invention also provides an application of a rope-shaped sensor for measuring artificial muscle driving force. The rope-shaped sensor is applied to the fingers of a soft robot to measure the artificial muscle driving force.

[0033] In summary, due to the adoption of the above technical solution, compared with the prior art, the present invention has at least the following beneficial effects:

[0034] When the present invention is used, the artificial muscle is connected via transmission, which will not affect the normal driving force output of the artificial muscle, and has accurate measurement and strong versatility.

[0035] At the same time, the conductive layer has two conductive fiber bundles, and any conductive fiber bundle can be directly connected to the measuring device, which is more convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of a rope sensor for measuring artificial muscle driving force according to an exemplary embodiment of the present invention.

[0037] Figure 2 The figure is a schematic diagram of the measurement principle of a rope-shaped sensor for measuring artificial muscle driving force according to an exemplary embodiment of the present invention.

[0038] Figure 3 The figure is a schematic flow chart of a method for preparing a rope-shaped sensor for measuring artificial muscle driving force according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with the examples and specific implementation methods. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following examples, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0040] In the description of the present invention, it is necessary to understand that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0041] like Figure 1 As shown, a rope-shaped sensor for measuring artificial muscle driving force of the present invention includes a support tube 101 , a sensing layer 102 and a conductive layer 104 .

[0042] In this embodiment, Figure 1 In (1), there is a support tube 101, which can be a capillary tube.

[0043] A sensing layer 102 is provided on the outer layer of the middle end of the support tube 101 for responding to changes in external pressure and outputting a resistance value; wherein the sensing layer 102 does not completely cover the outer layer of the support tube 101, but only covers a part of the middle end, and the length generally accounts for 5%-50%.

[0044] The outer layer of the sensing layer 102 is wrapped with a conductive layer 104; the conductive layer 104 is used to apply pressure to the sensing layer 102 when subjected to external force, and at the same time, the conductive fiber bundle in the conductive layer 104 can be directly connected to a measuring device to facilitate measurement.

[0045] In this embodiment, the prepared rope sensor is connected and fixed to the artificial muscle to be measured (ie, the rope sensor is placed inside the manipulator, and it is noted that the conductive layer and the supporting layer here must be firmly fixed to the artificial muscle), and then measurement can be performed.

[0046] like Figure 2 As shown, the contraction actuation of the artificial muscle causes a slight extension (transmission) of the rope-like sensor. During the extension process of the sensor, the conductive layer 104 and the support tube 101 are compressed inward due to the extension. Since the density of the support tube 101 is much greater than that of the conductive layer 104, the degree of inward compression is much smaller, which causes the conductive layer 104 and the support tube 101 to squeeze the sensing layer 102. The sensing layer 102 changes in resistance due to the squeezing, and the controller detects the driving force of the artificial muscle based on the change in resistance.

[0047] In this embodiment, a method for preparing a rope-shaped sensor for measuring artificial muscle driving force is also provided. Figure 3 As shown, the specific steps include:

[0048] S1: Select a capillary tube of suitable size as the support tube 101, and fix its two ends on two cylindrical metal rods with locking rings to facilitate subsequent process manufacturing.

[0049] In this embodiment, the support tube 101 is generally 500-5000 um in length, 4-40 um in inner diameter, and 7-70 um in outer diameter.

[0050] S2: preparing a sensing layer 102 at the middle end of the support tube 101 .

[0051] S2-1: Use a precision balance to accurately weigh the required carbon black powder, and add it to dimethyl sulfoxide (DMSO) solvent to prepare a 0.5% carbon slurry solution (ie, the ratio of carbon black powder to dimethyl sulfoxide solvent is 0.5:100).

[0052] The specific preparation method is:

[0053] After adding carbon black powder to dimethyl sulfoxide (DMSO) solvent, use a magnetic stirrer to stir for 30 minutes to avoid introducing too many bubbles and ensure that the carbon black is initially dispersed in the solvent to obtain a first solution; then transfer the first solution to an ultrasonic cleaner and perform ultrasonic treatment (for uniform dispersion) to obtain a second solution; then use a magnetic stirrer to stir the second solution (30 minutes) to obtain a carbon slurry solution; finally, store the carbon slurry solution in a sealed container to avoid long-term exposure to air to prevent volatilization and contamination.

[0054] S2-2: Dissolve the soluble plastic particles (PVA) in dimethyl sulfoxide (DMSO) solvent and stir for 30 minutes to form a uniform plastic solution.

[0055] S2-3: Add the carbon slurry solution to the plastic solution and stir thoroughly for 30 minutes to ensure that the carbon particles are evenly dispersed in the plastic solution, thereby obtaining a mixed solution.

[0056] In this embodiment, the mixed solution may be treated with ultrasound to further disperse the carbon particles to obtain better uniformity.

[0057] S2-4: Use electrospinning equipment to prepare the mixed solution into conductive fiber filaments.

[0058] In this embodiment, the electrospinning equipment includes a high voltage power supply, a syringe, a syringe pump, a nozzle and a receiving device.

[0059] The specific preparation method is: load the mixed solution into a syringe and connect it to a syringe pump; after setting the parameters, turn on the high-voltage power supply and the syringe pump, so that the mixed solution is sprayed out from the nozzle under the action of the high-voltage electric field to form long and thin fibers. The fibers are stretched and deposited on the receiving device under the action of the high-voltage electric field to form uniform conductive fiber filaments.

[0060] S2-5: Weaving the conductive fiber filaments at the middle end of the support tube 101 to form the sensing layer 102.

[0061] In this embodiment, ten conductive fiber strands can be combined into a conductive fiber bundle, and then a weaving machine is used to weave the conductive fiber bundle into a conductive fiber rope skin of suitable size at the middle end of the support tube 101, i.e., the sensing layer 102. Note that the sensing layer here does not cover the entire capillary, but only covers the middle part.

[0062] S3: using insulating fiber yarns to synthesize the conductive fiber bundle 103 and the insulating fiber bundle 105 respectively; and then weaving the conductive fiber bundle and the insulating fiber bundle on the outer layer of the sensing layer 102 to form the conductive layer 104.

[0063] S3-1: Use electrospinning equipment to prepare plastic solution into insulating fiber filaments; in order to improve toughness, thirty conductive fiber filaments are synthesized into a conductive fiber bundle 103, and thirty insulating fiber filaments are synthesized into an insulating fiber bundle 105.

[0064] S3-2: Use a weaving machine to weave 10 insulating fiber bundles 105 and 2 conductive fiber bundles 103 to weave a layer of semi-conductive fiber rope skin, namely the conductive layer 104, directly on the support tube 101 having the sensing layer 102.

[0065] In this embodiment, 10 insulating fiber bundles 105 and 2 conductive fiber bundles 103 are cross-woven together; the 2 conductive fiber bundles 103 are woven in parallel with each other to ensure that they do not touch each other so that they can be directly connected to a measuring instrument for subsequent measurement.

[0066] In this embodiment, the ends of the two conductive fiber bundles 103 appear at both ends of 104, so that the ends of the conductive fiber bundles 103 can be directly connected to the measuring instrument for measurement. What is measured here is the change in resistance of the sensing area between the two positions where the two conductive fiber bundles 103 contact the sensing layer 102 when the conductive layer 104 squeezes the sensing layer 102, rather than measuring the resistance of the entire sensing layer.

[0067] In this embodiment, the rope sensor is installed on the finger of the soft robot. When the finger is shaken left and right, and the finger is flexed and extended, the driving force of the muscle can be measured through the rope sensor. The rope sensor can also be directly woven into a net to form an integrated tactile sensing device, and the size of the object grasped in the hand can be decoupled by analyzing the grid points on the tactile sensing device that are subjected to pressure.

[0068] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present invention, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A rope sensor for measuring artificial muscle driving force, characterized in that: It comprises a support tube (101), a sensing layer (102) and a conductive layer (104); The outer surface of the support tube (101) is provided with a sensing layer (102); the outer surface of the sensing layer (102) is provided with a conductive layer (104); The support tube (101) plays a role of fixing and supporting; the sensing layer (102) is used to detect pressure and output a resistance value; and the conductive layer (104) is used to apply pressure to the sensing layer (102) when subjected to external force, and to connect an external measuring device.

2. The rope sensor for measuring artificial muscle driving force according to claim 1, characterized in that: The support tube (101) is a capillary tube.

3. The rope sensor for measuring artificial muscle driving force according to claim 1, characterized in that: The sensing layer (102) is located at the middle end of the support tube (101).

4. The rope sensor for measuring artificial muscle driving force according to claim 1, characterized in that: The density of the support tube (101) is greater than the density of the conductive layer (104).

5. A preparation method for preparing a rope sensor for measuring artificial muscle driving force as claimed in any one of claims 1 to 4, characterized in that: The specific steps include: S1: Select a capillary tube as a support tube (101); S2: preparing a sensing layer (102) at the middle end of the support tube (101); S3: preparing a conductive layer (104) on the outer surface of the sensing layer (102).

6. A preparation method according to claim 5, characterized in that: The S2 includes: S2-1: adding carbon black powder into dimethyl sulfoxide solvent to prepare a 0.5% carbon slurry solution; S2-2: dissolving soluble plastic particles in dimethyl sulfoxide solvent to form a plastic solution; S2-3: adding the carbon slurry solution to the plastic solution to obtain a mixed solution; S2-4: using an electrospinning device to prepare the mixed solution into conductive fiber filaments; S2-5: Weaving the conductive fiber filaments at the middle end of the support tube (101) to form a sensing layer (102).

7. A preparation method according to claim 6, characterized in that: In S2-1, the method for preparing the carbon slurry solution comprises: After adding carbon black powder into dimethyl sulfoxide solvent, stirring is performed for half an hour using a magnetic stirrer to obtain a first solution; Then the first solution is transferred to an ultrasonic cleaning apparatus and subjected to ultrasonic treatment to obtain a second solution; The second solution is then stirred using a magnetic stirrer to obtain a carbon slurry solution.

8. A preparation method according to claim 6, characterized in that: In S2-5, the preparation method of the sensing layer (102) is: First, ten conductive fiber threads are combined into a conductive fiber bundle, and then a weaving machine is used to weave the conductive fiber bundle into a conductive fiber rope skin, namely the sensing layer (102), at the middle end of the support tube (101).

9. A preparation method according to claim 5, characterized in that: The S3 includes: S3-1: using an electrospinning device to prepare a plastic solution into insulating fiber filaments; then synthesizing thirty conductive fiber filaments into a conductive fiber bundle (103), and synthesizing thirty insulating fiber filaments into an insulating fiber bundle (105); S3-2: Using a weaving machine, weave 10 insulating fiber bundles (105) and 2 conductive fiber bundles (103) onto the outer surface of the sensing layer (102) to obtain a conductive layer (104).

10. The use of a rope-shaped sensor for measuring artificial muscle driving force according to any one of claims 1 to 4, characterized in that: The rope-shaped sensor is applied to the fingers of a soft robot to measure the driving force of artificial muscles.

Images