Artificial muscle production system and operation method thereof

Abstract

The invention relates to a system for producing twisted or twisted-coiled artificial muscles under different production tensions from polymer fiber-based precursor fibers of any type and fineness, and to an operation method thereof In the artificial muscle production system of the invention, parameters such as the amount of twist, production tension, production speed, tension applied to the precursor fiber and the amount of muscle to be produced in the system can be precisely adjusted just before production. In the artificial muscle production system of the invention, artificial muscles are produced continuously and the lengths of the muscles to be produced are not limited to certain measurements. In the artificial muscle production system of the invention, the tension applied to the precursor fiber can be adjusted by stopping the system at any time of production (e.g. after nucleation).

Description

[0001] ARTIFICIAL MUSCLE PRODUCTION SYSTEM AND OPERATION METHOD THEREOF

[0002] The invention relates to a system for producing twisted or twisted-coiled artificial muscles under different production tensions from polymer fiber-based precursor fibers of any type and fineness, and to an operation method thereof.

[0003] State of the Art

[0004] Actuators, the first example of which dates back to the 1400s, have continued to diversify with technological advancements. Polymeric fiber-based twisted and coiled artificial muscles, invented in 2014, have attracted great interest due to their superior performance characteristics and cost-effectiveness, beyond being a new class of actuators. These muscles, produced by highly twisting a polymer fiber or sewing thread, can exhibit either linear or torsional actuation depending on the production method. Twisted coiled artificial muscles are anticipated to be used in various fields such as artificial organs, humanoid robots, energy harvesting devices, waste heat recovery systems, exoskeletons, smart agricultural textiles, and smart home textiles.

[0005] In the state of the art, artificial muscle production can only be performed in short lengths of around 15-20 cm and in batches. In the batch production method, one end of the precursor fiber in monofilament or multifilament form of a specific length is attached to a rotating motor, while a weight is hung from the other end of the precursor fiber to provide the required production tension. In order to twist the fiber, the weighted end is prevented from rotating while at the same time allowing the fiber to move in the axis direction. When the motor starts to rotate, the precursor fiber is twisted and a shortening of the precursor fiber occurs due to the twist. When the critical twist point is exceeded, coils similar to a helical spring are formed to reduce the stress on the fiber, and when the entire fiber gains a coiled structure, artificial muscle production is completed.

[0006] In the state of the art, the production of twisted or twisted-coiled artificial muscle can be done intermittently. In addition, it is not possible to ensure a standardized production due to variations in the characteristics and performance of the muscles produced in batch production. These limitations prevent the use of twisted or twisted-coiled artificial muscles in industrial-scale applications.

[0007] In the patent document no. US11 199181 B2, an invention on the production of polymer fiber-based mandrel coiled artificial muscle is provided. The method of the invention comprises the process steps of bending a precursor fiber; wrapping the twisted muscle fiber around a shaft; fixing the muscle fiber on the shaft using a fixing means; heating the muscle fiber to a predetermined temperature using a heating means. With the method presented in said patent document, mandrel coiled artificial muscle is produced, and there is no solution for the production of continuous coiled type artificial muscle. As a result, although some studies have been carried out to ensure the continuous production of muscles in the present art, no solution for the continuous production of twisted or twisted-coiled type artificial muscles can be achieved given the state of the art.

[0008] With the artificial muscle production systems in the present art, artificial muscles of only a very limited length (15-20 cm) can be produced. Artificial muscles with a limited length of 15-20 cm cannot be used in spinning, weaving or knitting machines in textile production processes. This is because these machines work with 1 .5-2 kilogram bobbins containing thousands of meters long yarn. As artificial muscle production is carried out with the artificial muscle production systems in the present art, a polymeric fiber of a certain length is connected to the end of a DC motor and a weight is hung on the end of the fiber and twisted in a vertical direction. The muscle length that can be obtained at the end of production is approximately 20-25% of the initial precursor fiber length, and the initial length of the muscle cannot be more than the ground clearance of the DC motor.

[0009] Artificial muscle production systems in the state of the art and the operation methods of said systems are both insufficient for the continuous production of twisted or twisted- coiled type artificial muscles, and it is only possible to produce artificial muscles with a limited length of 15-20 cm. In addition to all these limitations, it is not possible to precisely adjust the amount of twist, the production speed, the tension applied to the precursor fiber and the amount of muscle to be produced in the system just before production in the artificial muscle production systems of the present art.

[0010] Due to the aforementioned limitations of the present art, it has become necessary to present a system for the production of artificial muscles and the operation method thereof, in which all these problems are eliminated, continuous production of twisted or twisted-coiled artificial muscles is made possible, artificial muscle lengths are not limited to certain measurements, and parameters such as the amount of twist, production speed, tension applied to the precursor fiber and the amount of muscle to be produced in the system can be adjusted just before production.

[0011] Summary and Objects of the Invention

[0012] The invention describes a system for producing twisted or twisted-coiled artificial muscles under different production tensions from polymer fiber-based precursor fibers of any type and fineness and to an operation method thereof. In the artificial muscle production system of the invention, parameters such as the amount of twist, production speed, tension applied to the precursor fiber and the amount of muscle to be produced in the system can be precisely adjusted just before production. In the artificial muscle production system of the invention, artificial muscles are produced continuously and the lengths of the muscles to be produced are not limited to certain measurements. In the artificial muscle production system of the invention, the tension applied to the precursor fiber can be adjusted by stopping the system at any time of production.

[0013] An object of the invention is to provide a system for continuous production of twisted or twisted-coiled type artificial muscles, wherein parameters such as the amount of twist, the production speed, the tension applied to the precursor fiber and the amount of muscle to be produced in the system can be precisely adjusted just before production. In the artificial muscle production systems in the state of the art, artificial muscle production is provided by a DC motor and the amount of twist provided to the precursor fiber is unknown. Twisting is continued until the precursor fiber acquires a coiled structure. If it is desired to change the spring index of the finished muscle, the muscle can be released a little to open the twist, however, with this method, both the initial amount of twist on the muscle and the amount of twist after release cannot be determined. The amount of twist can only be approximated by subsequent inspections. In a system for the production of artificial muscle of the invention, the twisting process is provided by a stepper motor. Stepper motors work with step counts and the number of steps the motor will take during muscle production is predetermined in advance, so that the amount of twists to be inserted to the muscle can be adjusted before production. In the continuous twisted coiled artificial muscle production system, the data from the sensors are transferred to the computer and the control of the motors is provided by an arduino microprocessor module. In order to control the system with a computer, the arduino module is connected to the computer via a usb cable. A form application was carried out to control the system from the computer screen. In addition, the production load to be used during artificial muscle production can be selected in a wide range and it is even possible to change the production load after the critical twist point is exceeded. In the invention, the production load is not provided by a dead weight, but by transmitting the tension sensed by the load cell to the motor 3 and the rotation of the motor 3 in accordance with the incoming signal. This makes it possible to change the tension value in the system in a controlled manner and fine-tuning of the production under different tension values. Knowing the amount of twist is used to calculate the actuation value of the artificial muscle. This is an important feature that allows artificial muscle production to be carried out in accordance with the properties expected from the final product.

[0014] A further objective of the invention is to provide a system for the continuous production of a twisted or twisted-coiled type artificial muscle. In the invention, a system enabling continuous production of twisted or twisted-coiled type artificial muscles is provided by the same stepper motor performing the feeding and twisting processes. In the present system, production starts with a certain length of precursor fiber. In the system of the invention, a precursor fiber feeding spool is attached to the shaft of the stepper motor (motor 1). When the stepper motor is in the 0° position, it twists the precursor fiber that was previously fed into the system, and in the 90° position, it feeds the precursor fiber back into the system. In other words, after the artificial muscle production is completed in the 1 st cycle of the system, the untwisted part of the same precursor fiber is fed to the system with the rotation of the feeding spool and if the twisting process continues, continuous muscle production is achieved. In this way, it becomes possible to produce the desired amount of continuously in the system; and the stepper motor (motor 1 (2)) is brought to the 0 and 90 degree positions by a servo motor placed under motor 1. The number of rotations of the stepper motor at 0° and 90° positions is determined by the number of rotations entered on the control screen. For example, it can be commanded to rotate 600 full turns at 0° position and set to rotate 5 full turns at 90° position. In this way, it is possible to determine the length of the precursor fiber that the system will feed in one cycle and the amount of twist to be given to the fed precursor fiber. Thanks to the system of the invention continuously producing twisted or twisted-coiled type artificial muscles, it is also possible to use twisted or twisted-coiled type artificial muscles in industrial scale applications.

[0015] The invention provides a system for the production of twisted or twisted-coiled type artificial muscles in which the lengths of the artificial muscles are not limited to certain measurements. The capacity of the feeding spool determines the maximum length of artificial muscle to be produced in the system. In case a bobbin is used as a feeding spool in the system, 15000-20000 meters or even more depending on the yarn count, can be converted into artificial muscle. In the artificial muscle production systems in the present art, only artificial muscles of limited length (15-20 cm) can be produced and it is not possible to use these short muscles in textile production processes; in yarn, weaving or knitting machines. This is because these machines work with 1 .5-2 kilogram bobbins containing thousands of meters long yarn. Thanks to the system of the invention, this limitation is eliminated.

[0016] Description of the Drawings

[0017] Fig. 1. Representative top view of a system for producing twisted or twisted-coiled artificial muscle.

[0018] Fig. 2. Representative illustration of a side view of the feeding and twisting section of a system for producing twisted or twisted-coiled artificial muscle.

[0019] Fig. 3. Representative top view of a system for producing twisted or twisted-coiled artificial muscle operating under constant load.

[0020] Description of the References in the Drawings

[0021] 1 . Twisted or twisted-coiled artificial muscle production system.

[0022] 2. Motor 1

[0023] 3. Feeding spool

[0024] 4. Yarn brake

[0025] 5. Motor 1 placement platform

[0026] 6. Inductive sensor

[0027] 7. Rail

[0028] 8. Motor 2

[0029] 9. Artificial muscle winding spool 10. Motor 2 placement platform

[0030] 1 1 . Motor 2 platform and motor 3 connecting thread

[0031] 12. Motor 3 platform drive shaft

[0032] 13. Motor 3

[0033] 14. Travel spool mounted on motor 3 shaft

[0034] 15. Motor 3 placement platform

[0035] 16. Load cell and motor 3 platform connecting thread

[0036] 17. Load cell

[0037] 18. DC power source

[0038] 19. Servo motor

[0039] 20. Feeding and twisting module

[0040] 21. Spool

[0041] 22. Weight mass

[0042] 23. Microprocessor

[0043] 24. Computer

[0044] Detailed Description of the Invention

[0045] The invention relates to a system for producing twisted or twisted-coiled artificial muscles under different production tensions from polymer fiber-based precursor fibers of any type and fineness, and to an operation method thereof. In the artificial muscle production system of the invention, parameters such as the amount of twist, production speed, tension applied to the precursor fiber and the amount of muscle to be produced in the system can be precisely adjusted just before production. In the artificial muscle production system of the invention, artificial muscles are produced continuously and the lengths of the muscles to be produced are not limited to certain measurements. In the artificial muscle production system of the invention, the tension applied to the precursor fiber can be adjusted by stopping the system at any time of production (e.g. after nucleation).

[0046] A system for the production of twisted or twisted-coiled artificial muscles from polymer- based precursor fibers of all types and fineness under different production tensions comprises: • one motor 1 (2) as a stepper motor, one servo motor (19) and feeding spool (3) for feeding and twisting the precursor fiber,

[0047] • a yarn brake (4) for preventing the yarn from unwinding from the spool on its own during twisting,

[0048] • one motor 2 (8) as a stepper motor used for winding the produced artificial muscle, an artificial muscle winding spool (9), and two inductive sensors (6) that prevent the motor 2 (8), which is a stepper motor, from moving out of the system,

[0049] • two linear rails (7) for enabling the linear movement of the stepper motor,

[0050] • a motor 2 platform and a motor 3 connecting thread (1 1 ) for enabling production under the desired tension value,

[0051] • one stepper motor 3 (13) as a stepper motor and one load cell (17) for ensuring production under constant tension,

[0052] • one load cell and the motor 3 platform connecting thread (16),

[0053] • a microprocessor (23) for programming the motors and sensors in the system and a computer (24).

[0054] In a system of the invention for producing twisted or twisted-coiled artificial muscles from polymer-based precursor fibers of all types and fineness under different production tensions, the feeding of the precursor fiber and the twisting of the precursor fiber are carried out by a motor 1 (2) as a stepper motor. Motor 1 (2) is in different positions in the feeding and twisting steps. These positions are achieved by rotating the motor 1 placement platform (5), on which motor 1 (2), a stepper motor, is mounted, using a servo motor (19). In the twisting stage, the servo motor (19) is in the 0° position and in this position the feeding of the precursor fiber from the feeding spool (3) is prevented by the yarn brake (4). When the servo motor (19) is in the 90° position, the precursor fiber is fed. The artificial muscle produced by the system is wound on an artificial muscle winding spool (9) attached to the shaft of motor 2 (8), which is a stepper motor. During the feeding of the precursor fiber and the winding of the produced artificial muscle onto the artificial muscle winding spool (9), the motor 2 (8) moves in the direction of the motor 1 (2). Said movement is provided by the movement of the motor 2 placement platform (10), on which the motor 2 (8) is placed, between the rails (7). The production of the artificial muscle and the winding of the produced muscle on the artificial muscle winding spool (9) must be performed under constant tension. When measuring the tension of the system, firstly, the motor 2 placement platform (10) on which motor 2 (8) is placed is connected to the travel spool (14) mounted on motor 3 shaft with a motor 2 platform and a motor 3 connecting thread (11 ), and the motor 3 placement platform (15) on which motor 3 (13) is placed is connected to the load cell (17) with a load cell and a motor 3 platform connecting thread (16). The motor 3 placement platform (15) moves on a pair of motor 3 platform drive shafts (12). In the system, the tension is measured instantaneously with the load cell (17) and a signal is sent to motor 3 (13). An inductive sensor (6) is used to prevent motor 2 (8) from leaving the system during the twisting and winding stages. In the system, the electricity required for the operation of the motors is provided by the DC power supply (18). The continuous twisted and coiled artificial muscle production system can also be operated using an external load. In this state of the system, the load cell (17) measuring the tension and the motor 3 (13) adjusting the tension are disabled. The required production load is provided by the weight mass (22) suspended on the end of the rope, which is attached to the motor 2 placement platform (10) and brought to a vertical position with the help of a spool (21 ).

[0055] The continuous artificial muscle production system of the invention is controlled by a computer (24). before starting to run the system, the diameter of the precursor fiber, the length of the precursor fiber to be converted into artificial muscle in one cycle of the system, the number of cycles of the system, the amount of twist to be made to the precursor fiber and the production load values to be applied during twisting are entered on the interface screen and then the START button is pressed and the "start" message is sent to the arduino mega from the serial port. The title of the "START" button changes to "STOP". At any desired moment in the process, the whole process can be stopped by pressing the "STOP" button. After pressing the "START" button, the "PAUSE" button also becomes active. With the aforementioned pause button, the operation can be paused at any desired moment of the process. When a pause is made, the title of the "PAUSE" button changes to "RESUME". By pressing the "RESUME" button, operations can be continued from where they left off. The amount of muscle to be produced with the system is determined by the number of cycles. After the production parameters are entered into the system, the "START" button is pressed.

[0056] The operation method of a system of the invention for the continuous production of twisted or twisted-coiled artificial muscles from polymer-based precursor fibers of all types and fineness under different production tensions comprises the process steps of: i. setting the servomotor (19) in the 0° position and the motor 1 (2) in the twisting position to bring all system elements to the initial position, placing the feeding spool (3) on the shaft of the motor 1 (2), positioning the motor 2 (8) in front of the inductive sensor (6), connecting one end of the precursor fiber to the artificial muscle winding spool (9) by the operator and keeping the motor 3 (13) in the standby position, ii. upon the start of operation of the system, the load cell (17) measures the tension on the precursor fiber and sends a signal the motor 3 (13) to move the motor 2

[0057] (8) to the appropriate position until the required tension is reached, iii. once the tension required for the operation of the system is reached, the shaft of the motor 1 (2) rotates, twisting the precursor fiber, and the tension on the precursor fiber increases due to the shortening of the twist during the twisting process, and the load cell (17) sends a signal to the motor 3 (13) to adjust the tension, iv. Motor 3 (13) rotates clockwise, allowing motor 2 (8) to move in the direction of motor 1 (2), v. after the twisting process is completed and the twisted coiled muscle is produced, motor 2 (8) is activated to wind the produced muscle, and in the meantime, motor 2 (8) moves in the direction of motor 1 (2) and motor 3 (13) rotates clockwise to allow motor 2 (8) to move towards motor 1 (2), vi. when the winding of the produced muscle on the artificial muscle winding spool

[0058] (9) is completed, the servo motor (19) rotates to bring the motor 1 (2) to the feeding position and the motor 3 (13) rotates counterclockwise to pull the motor 2 (8) in the standby position back to the starting position, vii. when the feeding phase is completed, the servo motor (19) rotates to return the motor 1 (2) back to the twisting position, thus completing a system cycle.

[0059] The system of the invention is suitable for creating any number of cycles. No nucleation is observed after the first cycle of the system, and the artificial muscle is created as a continuation of the muscle produced in the previous system, thus ensuring integrity between cycles. The artificial muscle produced is suitable for direct use in conventional textile machines.

Claims

CLAIMS1 . A system for producing twisted or twisted-coiled artificial muscles, characterized in that it comprises:• one motor 1 (2) as a stepper motor, one servo motor (19) and feeding spool (3) for feeding and twisting the precursor fiber,• a yarn brake (4) for preventing the yarn from unwinding from the spool on its own during twisting,• one motor 2 (8) as a stepper motor used for winding the produced artificial muscle, an artificial muscle winding spool (9), and two inductive sensors (6) that prevent the motor 2 (8), which is a stepper motor, from moving out of the system,• two rails (7) for enabling the linear movement of the stepper motor,• a motor 2 platform and a motor 3 connecting thread (1 1 ) for enabling production under the desired tension value,• one stepper motor 3 (13) as a stepper motor and one load cell (17) for ensuring production under constant tension,• one load cell and the motor 3 platform connecting thread (16),• a microprocessor (23) for programming the motors and sensors in the system and a computer (24).

2. An operation method of a system for producing twisted or twisted-coiled artificial muscles, characterized in that it comprises the process steps of: i. setting the servomotor (19) in the 0° position and the motor 1 (2) in the twisting position to bring all system elements to the initial position, placing the feeding spool (3) on the shaft of the motor 1 (2), positioning the motor 2 (8) in front of the inductive sensor (6), connecting one end of the precursor fiber to the artificial muscle winding spool (9) by the operator and keeping the motor 3 (13) in the standby position, ii. upon the start of operation of the system, the load cell (17) measures the tension on the precursor fiber and sends a signal the motor 3 (13) to move the motor 2 (8) to the appropriate position until the required tension is reached, iii. once the tension required for the operation of the system is reached, the shaft of the motor 1 (2) rotates, twisting the precursor fiber, and the tension on theprecursor fiber increases due to the shortening of the twist during the twisting process, and the load cell (17) sends a signal to the motor 3 (13) to adjust the tension, iv. Motor 3 (13) rotates clockwise, allowing motor 2 (8) to move in the direction of motor 1 (2), v. after the twisting process is completed and the twisted coiled muscle is produced, motor 2 (8) is activated to wind the produced muscle, and in the meantime, motor 2 (8) moves in the direction of motor 1 (2) and motor 3 (13) rotates clockwise to allow motor 2 (8) to move towards motor 1 (2), vi. when the winding of the produced muscle on the artificial muscle winding spool (9) is completed, the servo motor (19) rotates to bring the motor 1 (2) to the feeding position and the motor 3 (13) rotates counterclockwise to pull the motor 2 (8) in the standby position back to the starting position, vii. when the feeding phase is completed, the servo motor (19) rotates to return the motor 1 (2) back to the twisting position, thus completing a system cycle.

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