Memory alloy multifunctional test method

Abstract

The invention relates to the technical field of test methods, in particular to a memory alloy multifunctional test method which comprises the following steps: S101, acquiring displacement, resistance and pressure data of a memory alloy wire after electrification; s103, according to the input parameters, the power-on voltage, the stretching duty ratio and the maintaining duty ratio of the memory alloy wire at different temperatures are obtained; and S105, fatigue testing is conducted on different memory alloy wires, the fatigue degree of the memory alloy wires is judged by detecting the running states of the memory alloy wires, and resistance, displacement and pressure data of the memory alloy wires are detected in real time. According to the invention, various performances of the memory alloy wires with various structures can be detected, and the optimal control mode is selected to improve the application effect of the memory alloy wires on the air valve.

Description

Technical Field

[0001] The invention relates to the technical field of testing methods, and in particular to a multifunctional testing method for memory alloys. Background Art

[0002] Memory alloys, especially titanium-nickel shape memory alloys, have unique shape memory effect, high ductility, wear resistance, corrosion resistance, superelasticity and other excellent properties. These properties make memory alloys have broad application prospects in aerospace, medical equipment, consumer electronics and other fields.

[0003] In order to ensure the quality and performance of memory alloys in practical applications, comprehensive performance parameter tests are required. These tests include appearance inspection, physical property tests (such as hardness, tensile strength, elongation at break, elastic modulus, etc.), chemical property tests (such as chemical composition, corrosion resistance, aging resistance, etc.), thermal property tests (such as phase change temperature, thermal expansion coefficient, thermal conductivity, etc.) and environmental adaptability tests (such as temperature adaptability, humidity adaptability, vibration adaptability, etc.).

[0004] Due to the differences in memory alloy wires, structural types and usage requirements, it is necessary to test the performance parameters of different memory alloy wires. In addition, the control parameters will also be different. The optimal control parameters can significantly improve the control accuracy and service life of memory alloy wire products. The existing performance tests on memory alloy wire products often only test a single performance, but lack a comprehensive test method for multiple performances of memory alloy wires and a comprehensive judgment to obtain the optimal control method. Summary of the invention

[0005] To solve the above problems, the present invention provides a multifunctional testing method for memory alloys, which can detect multiple performances of multiple memory alloy wires on the gas valve, and comprehensively determine the optimal control method of the memory alloy wires, thereby improving the application effect of the memory alloy wires on the gas valve.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: to provide a multifunctional testing method for memory alloy, comprising the following steps:

[0007] S101: Obtaining displacement, resistance and pressure data of the memory composite wire after power is supplied;

[0008] S103: according to the input parameters, obtaining the power-on voltage, stretching duty cycle and maintaining duty cycle of the memory alloy wire at different temperatures;

[0009] S105: Perform fatigue tests on different memory alloy wires, detect the operating status of the memory alloy wires to determine the fatigue degree of the memory alloy wires, and detect the resistance, displacement and pressure data of the memory alloy wires in real time.

[0010] Furthermore, the S101 includes the following specific steps:

[0011] S101.1: The host computer sets the current and power-on time of the memory alloy wire;

[0012] S101.2: Receive and parse host computer data;

[0013] S101.3: Setting the controllable power supply current value;

[0014] S101.4: Turn on the MOS tube to energize the memory alloy wire;

[0015] S101.5: reading the voltage value and current value of the memory alloy wire, and calculating the resistance value of the memory alloy wire;

[0016] S101.6: Read the voltage value of the pressure sensor, and calculate the pressure value based on the linear relationship between the voltage value of the pressure sensor and the pressure value;

[0017] S101.7: Read displacement sensor data;

[0018] S101.8: Send resistance, displacement and pressure data to the upper computer;

[0019] S101.9: Determine whether the power-on time of the memory alloy wire has ended. If the power-on time has ended, the test ends and an end instruction is sent; if the power-on time has not ended, return to step S101.9 and continue until the power-on time ends.

[0020] Furthermore, the S103 includes the following specific steps:

[0021] S103.1: The host computer sets the displacement value, stretching action time, position holding time, power-on voltage value and temperature range of the memory alloy wire;

[0022] S103.2: Receive and parse host computer data;

[0023] S103.3: Initialize the constant temperature box temperature and assign the minimum temperature within the temperature range;

[0024] S103.4: Send thermostat control instructions;

[0025] S103.5: Wait for the temperature of the thermostat to reach the set temperature, and determine whether the temperature of the thermostat has reached the set temperature. If it has not reached the set temperature, continue to wait until the thermostat reaches the set temperature. If the thermostat reaches the set temperature, set the initial voltage value of the controllable power supply.

[0026] S103.6: Initialize stretch PWM duty cycle and maintain PWM duty cycle;

[0027] S103.7: Read the current data of the displacement sensor and record it as the initial position;

[0028] S103.8: Turn on the MOS tube, set the initial stretch PWM duty cycle, and energize the memory alloy wire;

[0029] S103.9: Determine whether the stretching time has ended. If the stretching time has not ended, continue waiting and determining. If the stretching time has ended, read the displacement sensor data.

[0030] S103.10: Determine whether the memory alloy wire has reached the set displacement value. If the memory alloy wire has not reached the set displacement value, the value of the PWM duty cycle is increased by 1% of the high level time and then returns to step S103.8. If the memory alloy wire has reached the set displacement value, the PWM duty cycle is maintained and the memory alloy wire is energized.

[0031] S103.11: Read displacement sensor data;

[0032] S103.12: Determine whether the memory alloy wire is maintained at the set displacement value. If the memory alloy wire is not maintained at the set displacement value, then maintain the PWM duty cycle value increased by 1% of the high level time and then return to step S103.8. If the memory alloy wire is maintained at the set displacement value, then determine whether the maintenance time is over.

[0033] S103.13: If the holding time has not ended, return to step S103.11. If the holding time has ended, send the incubator temperature value, stretch duty cycle and holding duty cycle data to the host computer;

[0034] S103.14: Determine whether the thermostat has reached the maximum set temperature. If not, increase the thermostat temperature by 5 degrees Celsius and return to step S103.5. If the thermostat temperature reaches the maximum set temperature, the test ends and an end command is sent.

[0035] Furthermore, the S105 includes the following specific steps:

[0036] S105.1: The upper computer sets the stretching action time and duty cycle, the position holding time and duty cycle, the power-on voltage value and the abnormal resistance value;

[0037] S105.2: Receive and parse host computer data;

[0038] S105.3: Setting the initial voltage value of the controllable power supply;

[0039] S105.41: Read displacement sensor data;

[0040] S105.42: Read the voltage value of the pressure sensor, and calculate the pressure value based on the linear relationship between the voltage value of the pressure sensor and the pressure value;

[0041] S105.43: Determine whether the detected resistance value of the memory alloy wire exceeds the set abnormal resistance value. If the resistance value of the memory alloy wire exceeds the set abnormal resistance value, the fatigue test ends. If the resistance value of the memory alloy wire does not exceed the set abnormal resistance value, send the fatigue times, displacement value and pressure value and return to step S105.41;

[0042] S105.51: Turn on the MOS tube, set the initial stretch PWM duty cycle, and energize the memory alloy wire;

[0043] S105.52: Determine whether the stretching time has ended. If not, continue to wait and make continuous judgments. If it has ended, set the PWM duty cycle to maintain and energize the memory alloy wire.

[0044] S105.53: Determine whether the maintenance time has ended. If not, continue to wait and make continuous judgments. If it has ended, the fatigue times value increases by 1, the MOS tube is turned off, and the memory alloy wire is powered off.

[0045] S105.54: Read the voltage and current values ​​of the memory alloy wire, and calculate the resistance value of the memory alloy wire;

[0046] S105.55: Determine whether the resistance value of the memory alloy wire is greater than the abnormal resistance value. If the resistance value of the memory alloy wire is not greater than the abnormal resistance value, return to step S105.51. If the resistance value of the memory alloy wire is greater than the abnormal resistance value, the fatigue test ends and an end instruction is sent.

[0047] Among them, steps S105.41 to S105.43 and steps S105.51 to S105.55 are performed simultaneously.

[0048] Furthermore, the data collection process involved in steps S101.6 to S101.8 includes the following steps:

[0049] S1001: The host computer sends a data collection instruction;

[0050] S1002: The system is initialized and N is cleared;

[0051] S1003: Turn on the Nth switch;

[0052] S1004: Reset the SPI and 485 communication timing;

[0053] S1005: Wait for the communication success instruction. If the communication success instruction is received, the process proceeds to step S1006. If the communication success instruction is not received, the timing is started to determine whether the waiting time has timed out. If the waiting time has timed out, the communication error is reported and the process proceeds to step S1006. If the waiting time has not timed out, the process returns to step S1005 and loops.

[0054] S1006: turn off the Nth switch and send data N+1 to the upper computer;

[0055] S1007: Determine whether the channel has been collected. If the channel has been collected, end the data collection and wait for the host computer instruction. If the channel has not been collected, return to step S1003;

[0056] Wherein N is the number of gas paths of the gas valve, N≥1.

[0057] Furthermore, the range of N is 1-3.

[0058] The technical solution of the present invention has the following advantages:

[0059] 1. The testing method for memory alloy wire designed in the present invention can perform multifunctional tests on different types of memory alloy wire products, such as fatigue, resistance change of memory alloy wire, displacement and pressure value generated by memory alloy wire, etc., and can derive the above-mentioned change rate and curve value at different temperatures.

[0060] 2. By inputting different required parameters for memory alloy wire, such as displacement, displacement time, pressure change and change speed, and temperature control range, the optimal control voltage and optimal response speed for the memory alloy wire structure can be given according to the input requirements, which can significantly improve the control accuracy and service life of the equipment.

[0061] It should be appreciated that all combinations of the foregoing concepts, as well as additional concepts described in greater detail below, may be considered to be part of the inventive subject matter of the present disclosure, provided such concepts are not mutually inconsistent.

[0062] The foregoing and other aspects, embodiments and features of the present invention can be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the present invention, such as the features and / or beneficial effects of the exemplary embodiments, will be apparent from the following description or learned from the practice of the specific embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The accompanying drawings are not drawn to scale according to actual reference objects. In the accompanying drawings, each identical or nearly identical component shown in various figures may be represented by the same reference numeral. For the sake of clarity, not every component is labeled in each figure. Now, embodiments of various aspects of the present invention will be described by way of example and with reference to the accompanying drawings, in which:

[0064] Figure 1 The figure is a flow chart for obtaining displacement, resistance and pressure data of the memory alloy wire in the present invention.

[0065] Figure 2 The present invention is a flow chart for obtaining the power-on voltage, stretching duty cycle and maintaining duty cycle of the memory alloy wire at different temperatures according to the input parameters.

[0066] Figure 3 The present invention is a flow chart for performing fatigue tests on different memory alloy wires, detecting the operating state of the memory alloy wires to determine the fatigue degree of the memory alloy wires, and detecting the resistance, displacement and pressure data of the memory alloy wires in real time.

[0067] Figure 4 This is a flow chart of the present invention for collecting multi-channel data and timeout detection.

[0068] Figure 5 This is a curve diagram showing the relationship between the output duty cycle and the displacement value of the memory alloy wire.

[0069] Figure 6 The figure is a graph of the stretching duty ratio and the maintaining duty ratio of the memory alloy wire at different temperatures.

[0070] Figure 7 This is a diagram of the air pressure status in the air valve when the memory alloy wire is running at different temperatures.

[0071] Figure 8 It is a linear relationship diagram between the voltage value of the pressure sensor used in the present invention and the pressure value of the memory alloy wire. DETAILED DESCRIPTION

[0072] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meaning understood by people with general skills in the field to which the present invention belongs.

[0073] The words "first", "second" and similar terms used in the patent specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular form "a" or "an" shall not be construed as "a" or "an";

[0074] The words “a”, “an”, “the” and the like do not denote a limitation of quantity, but rather denote the presence of at least one.

[0075] The words "include" or "comprises" and the like mean that the elements or objects appearing before "includes" or "comprises" include the features, wholes, steps, operations, elements and / or components listed after "includes" or "comprises", and do not exclude the existence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0076] The embodiment of the present invention provides a multifunctional testing method for memory alloy, comprising the following steps:

[0077] S101: Obtaining displacement, resistance and pressure data of the memory composite wire after power is supplied;

[0078] S103: according to the input parameters, obtaining the power-on voltage, stretching duty cycle and maintaining duty cycle of the memory alloy wire at different temperatures;

[0079] S105: Perform fatigue tests on different memory alloy wires, detect the operating status of the memory alloy wires to determine the fatigue degree of the memory alloy wires, and detect the resistance, displacement and pressure data of the memory alloy wires in real time.

[0080] In some embodiments of the present invention, the S101 includes the following specific steps:

[0081] S101.1: The host computer sets the current and power-on time of the memory alloy wire;

[0082] S101.2: Receive and parse host computer data;

[0083] S101.3: Setting the controllable power supply current value;

[0084] S101.4: Turn on the MOS tube to energize the memory alloy wire;

[0085] S101.5: reading the voltage value and current value of the memory alloy wire, and calculating the resistance value of the memory alloy wire;

[0086] S101.6: Read the voltage value of the pressure sensor and calculate the pressure value based on the linear relationship between the pressure sensor voltage value and the pressure value; see Figure 8 The linear relationship between the pressure sensor voltage value and the pressure value is shown. The 0-100 range of the pressure sensor corresponds to a voltage of 0-3.3V.

[0087] S101.7: Read displacement sensor data;

[0088] S101.8: Send resistance, displacement and pressure data to the upper computer;

[0089] S101.9: Determine whether the power-on time of the memory alloy wire has ended. If the power-on time has ended, the test ends and an end instruction is sent; if the power-on time has not ended, return to step S101.9 and continue until the power-on time ends.

[0090] In some embodiments of the present invention, the S103 includes the following specific steps:

[0091] S103.1: The host computer sets the displacement value, stretching action time, position holding time, power-on voltage value and temperature range of the memory alloy wire;

[0092] S103.2: Receive and parse host computer data;

[0093] S103.3: Initialize the constant temperature box temperature and assign the minimum temperature within the temperature range;

[0094] S103.4: Send thermostat control instructions;

[0095] S103.5: Wait for the temperature of the thermostat to reach the set temperature, and determine whether the temperature of the thermostat has reached the set temperature. If it has not reached the set temperature, continue to wait until the thermostat reaches the set temperature. If the thermostat reaches the set temperature, set the initial voltage value of the controllable power supply.

[0096] S103.6: Initialize stretch PWM duty cycle and maintain PWM duty cycle;

[0097] S103.7: Read the current data of the displacement sensor and record it as the initial position;

[0098] S103.8: Turn on the MOS tube, set the initial stretch PWM duty cycle, and energize the memory alloy wire;

[0099] S103.9: Determine whether the stretching time has ended. If the stretching time has not ended, continue waiting and determining. If the stretching time has ended, read the displacement sensor data.

[0100] S103.10: Determine whether the memory alloy wire has reached the set displacement value. If the memory alloy wire has not reached the set displacement value, the value of the PWM duty cycle is increased by 1% of the high level time and then returns to step S103.8. If the memory alloy wire has reached the set displacement value, the PWM duty cycle is maintained and the memory alloy wire is energized.

[0101] S103.11: Read displacement sensor data;

[0102] S103.12: Determine whether the memory alloy wire is maintained at the set displacement value. If the memory alloy wire is not maintained at the set displacement value, then maintain the PWM duty cycle value increased by 1% of the high level time and then return to step S103.8. If the memory alloy wire is maintained at the set displacement value, then determine whether the maintenance time is over.

[0103] S103.13: If the holding time has not ended, return to step S103.11. If the holding time has ended, send the incubator temperature value, stretch duty cycle and holding duty cycle data to the host computer;

[0104] S103.14: Determine whether the thermostat has reached the maximum set temperature. If not, increase the thermostat temperature by 5 degrees Celsius and return to step S103.5. If the thermostat temperature reaches the maximum set temperature, the test ends and an end command is sent.

[0105] In some embodiments of the present invention, S105 includes the following specific steps:

[0106] S105.1: The upper computer sets the stretching action time and duty cycle, the position holding time and duty cycle, the power-on voltage value and the abnormal resistance value;

[0107] S105.2: Receive and parse host computer data;

[0108] S105.3: Setting the initial voltage value of the controllable power supply;

[0109] S105.41: Read displacement sensor data;

[0110] S105.42: Read the voltage value of the pressure sensor and calculate the pressure value based on the linear relationship between the pressure sensor voltage value and the pressure value; see Figure 8 The linear relationship between the pressure sensor voltage value and the pressure value is shown. The 0-100 range of the pressure sensor corresponds to a voltage of 0-3.3V.

[0111] S105.43: Determine whether the detected resistance value of the memory alloy wire exceeds the set abnormal resistance value. If the resistance value of the memory alloy wire exceeds the set abnormal resistance value, the fatigue test ends. If the resistance value of the memory alloy wire does not exceed the set abnormal resistance value, send the fatigue times, displacement value and pressure value and return to step S105.41;

[0112] S105.51: Turn on the MOS tube, set the initial stretch PWM duty cycle, and energize the memory alloy wire;

[0113] S105.52: Determine whether the stretching time has ended. If not, continue to wait and make continuous judgments. If it has ended, set the PWM duty cycle to maintain and energize the memory alloy wire.

[0114] S105.53: Determine whether the maintenance time has ended. If not, continue to wait and make continuous judgments. If it has ended, the fatigue times value increases by 1, the MOS tube is turned off, and the memory alloy wire is powered off.

[0115] S105.54: Read the voltage and current values ​​of the memory alloy wire, and calculate the resistance value of the memory alloy wire;

[0116] S105.55: Determine whether the resistance value of the memory alloy wire is greater than the abnormal resistance value. If the resistance value of the memory alloy wire is not greater than the abnormal resistance value, return to step S105.51. If the resistance value of the memory alloy wire is greater than the abnormal resistance value, the fatigue test ends and an end instruction is sent.

[0117] Among them, steps S105.41 to S105.43 and steps S105.51 to S105.55 are performed simultaneously.

[0118] In some embodiments of the present invention, the process of collecting data involved in steps S101.6 to S101.8 includes the following steps:

[0119] S1001: The host computer sends a data collection instruction;

[0120] S1002: The system is initialized and N is cleared;

[0121] S1003: Turn on the Nth switch;

[0122] S1004: Reset the SPI and 485 communication timing;

[0123] S1005: Wait for the communication success instruction. If the communication success instruction is received, the process proceeds to step S1006. If the communication success instruction is not received, the timing is started to determine whether the waiting time has timed out. If the waiting time has timed out, the communication error is reported and the process proceeds to step S1006. If the waiting time has not timed out, the process returns to step S1005 and loops.

[0124] S1006: turn off the Nth switch and send data N+1 to the upper computer;

[0125] S1007: Determine whether the channel has been collected. If the channel has been collected, end the data collection and wait for the host computer instruction. If the channel has not been collected, return to step S1003;

[0126] Wherein N is the number of gas paths of the gas valve, N≥1.

[0127] In some embodiments of the present invention, N ranges from 1 to 3.

[0128] This system collects multi-channel data flow, has timeout detection, and can collect data from multiple mechanisms simultaneously.

[0129] See also Figure 5 As shown in the figure, the memory alloy wire is energized for 500ms with different duty ratios. Figure 5 It is the maximum displacement curve generated by the memory alloy wire. When the maximum displacement value is set to 1mm, the output control stretching duty cycle should be controlled at 68%, otherwise the displacement of the memory alloy wire will exceed the set displacement value, resulting in over-stretching, which greatly affects the life of the wire. The goal of the test method designed by the present invention is to obtain the displacement change curve data and test the output duty cycle.

[0130] PWM duty cycle refers to the ratio of the high level time in the pulse wave to the total cycle, expressed as a percentage. Duty cycle = high level time / total cycle × 100%. For example, if the high level time of a PWM signal is 5 milliseconds and the total cycle is 10 milliseconds, the duty cycle is 50%.

[0131] PWM duty cycle is a key parameter in PWM signal. By adjusting the duty cycle, effective control of analog signal can be achieved.

[0132] See also Figure 6 As shown, a graph showing the tensile duty cycle and the maintenance duty cycle of the tested memory alloy wire at different temperatures is shown.

[0133] See also Figure 7 As shown, Figure 7 It is shown that the air pressure state when the duty cycle is running at different temperatures is stable, and the optimal control method selected by the method of the present invention can enable the memory alloy wire to completely seal the air valve.

[0134] The testing method for memory alloy wire designed in the present invention can perform multifunctional tests on different types of memory alloy wire products, such as fatigue, resistance change of memory alloy wire, displacement and pressure value generated by memory alloy wire, etc., and can derive the above-mentioned change rate and curve value at different temperatures.

[0135] By inputting different required parameters for the memory alloy wire, such as displacement, displacement time, pressure change and change speed, and temperature control range, the optimal control voltage and optimal response speed for the memory alloy wire structure can be given according to the input requirements, which can significantly improve the control accuracy and service life of the equipment.

[0136] This test method can evaluate the adaptability of memory alloy wire under different environmental conditions by simultaneously testing multiple performance parameters. For example, the temperature adaptability test can check the performance of the alloy wire at different temperatures to ensure that it can work normally at extreme temperatures; the humidity adaptability test can verify the stability of the alloy wire in a high humidity environment. These tests help determine the optimal use conditions for the memory alloy wire to avoid performance degradation or failure due to environmental factors in actual applications. The memory alloy wire in the present invention is applied to the air valve. By testing multiple air channels on the air valve, the optimal control method for the memory alloy wire is selected, which greatly improves the application effect and overall sealing of the air valve.

[0137] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. A person with ordinary knowledge in the technical field to which the present invention belongs may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the definition of the claims.

Claims

1. A multifunctional testing method for memory alloys, characterized in that: The following steps are involved: S101: Obtaining displacement, resistance and pressure data of the memory composite wire after power is supplied; S103: according to the input parameters, obtaining the power-on voltage, stretching duty cycle and maintaining duty cycle of the memory alloy wire at different temperatures; S105: Perform fatigue tests on different memory alloy wires, detect the operating status of the memory alloy wires to determine the fatigue degree of the memory alloy wires, and detect the resistance, displacement and pressure data of the memory alloy wires in real time.

2. The multifunctional testing method for memory alloy according to claim 1, characterized in that: The S101 includes the following specific steps: S101.1: The host computer sets the current and power-on time of the memory alloy wire; S101.2: Receive and parse host computer data; S101.3: Setting the controllable power supply current value; S101.4: Turn on the MOS tube to energize the memory alloy wire; S101.5: reading the voltage value and current value of the memory alloy wire, and calculating the resistance value of the memory alloy wire; S101.6: Read the voltage value of the pressure sensor, and calculate the pressure value based on the linear relationship between the voltage value of the pressure sensor and the pressure value; S101.7: Read displacement sensor data; S101.8: Send resistance, displacement and pressure data to the upper computer; S101.9: Determine whether the power-on time of the memory alloy wire has ended. If the power-on time has ended, the test ends and an end instruction is sent; if the power-on time has not ended, return to step S101.9 and continue until the power-on time ends.

3. The multifunctional testing method for memory alloy according to claim 1, characterized in that: The S103 includes the following specific steps: S103.1: The host computer sets the displacement value, stretching action time, position holding time, power-on voltage value and temperature range of the memory alloy wire; S103.2: Receive and parse host computer data; S103.3: Initialize the constant temperature box temperature and assign the minimum temperature within the temperature range; S103.4: Send thermostat control instructions; S103.5: Wait for the temperature of the thermostat to reach the set temperature, and determine whether the temperature of the thermostat has reached the set temperature. If it has not reached the set temperature, continue to wait until the thermostat reaches the set temperature. If the thermostat reaches the set temperature, set the initial voltage value of the controllable power supply. S103.6: Initialize stretch PWM duty cycle and maintain PWM duty cycle; S103.7: Read the current data of the displacement sensor and record it as the initial position; S103.8: Turn on the MOS tube, set the initial stretch PWM duty cycle, and energize the memory alloy wire; S103.9: Determine whether the stretching time has ended. If the stretching time has not ended, continue waiting and determining. If the stretching time has ended, read the displacement sensor data. S103.10: Determine whether the memory alloy wire has reached the set displacement value. If the memory alloy wire has not reached the set displacement value, the value of the PWM duty cycle is increased by 1% of the high level time and then returns to step S103.

8. If the memory alloy wire has reached the set displacement value, the PWM duty cycle is maintained and the memory alloy wire is energized. S103.11: Read displacement sensor data; S103.12: Determine whether the memory alloy wire is maintained at the set displacement value. If the memory alloy wire is not maintained at the set displacement value, then maintain the PWM duty cycle value increased by 1% of the high level time and then return to step S103.

8. If the memory alloy wire is maintained at the set displacement value, then determine whether the maintenance time is over. S103.13: If the holding time has not ended, return to step S103.

11. If the holding time has ended, send the incubator temperature value, stretch duty cycle and holding duty cycle data to the host computer; S103.14: Determine whether the thermostat has reached the maximum set temperature. If not, increase the thermostat temperature by 5 degrees Celsius and return to step S103.

5. If the thermostat temperature reaches the maximum set temperature, the test ends and an end command is sent.

4. The multifunctional testing method for memory alloy according to claim 1, characterized in that: The S105 includes the following specific steps: S105.1: The upper computer sets the stretching action time and duty cycle, the position holding time and duty cycle, the power-on voltage value and the abnormal resistance value; S105.2: Receive and parse host computer data; S105.3: Setting the initial voltage value of the controllable power supply; S105.41: Read displacement sensor data; S105.42: Read the voltage value of the pressure sensor, and calculate the pressure value based on the linear relationship between the voltage value of the pressure sensor and the pressure value; S105.43: Determine whether the detected resistance value of the memory alloy wire exceeds the set abnormal resistance value. If the resistance value of the memory alloy wire exceeds the set abnormal resistance value, the fatigue test ends. If the resistance value of the memory alloy wire does not exceed the set abnormal resistance value, send the fatigue times, displacement value and pressure value and return to step S105.41; S105.51: Turn on the MOS tube, set the initial stretch PWM duty cycle, and energize the memory alloy wire; S105.52: Determine whether the stretching time has ended. If not, continue to wait and make continuous judgments. If it has ended, set the PWM duty cycle to maintain and energize the memory alloy wire. S105.53: Determine whether the maintenance time has ended. If not, continue to wait and make continuous judgments. If it has ended, the fatigue times value increases by 1, the MOS tube is turned off, and the memory alloy wire is powered off. S105.54: Read the voltage and current values ​​of the memory alloy wire, and calculate the resistance value of the memory alloy wire; S105.55: Determine whether the resistance value of the memory alloy wire is greater than the abnormal resistance value. If the resistance value of the memory alloy wire is not greater than the abnormal resistance value, return to step S105.

51. If the resistance value of the memory alloy wire is greater than the abnormal resistance value, the fatigue test ends and an end instruction is sent. Among them, steps S105.41 to S105.43 and steps S105.51 to S105.55 are performed simultaneously.

5. The multifunctional testing method for memory alloy according to claim 2, characterized in that: The process of collecting data involved in steps S101.6 to S101.8 includes the following steps: S1001: The host computer sends a data collection instruction; S1002: The system is initialized and N is cleared; S1003: Turn on the Nth switch; S1004: Reset the SPI and 485 communication timing; S1005: Wait for the communication success instruction. If the communication success instruction is received, the process proceeds to step S1006. If the communication success instruction is not received, the timing is started to determine whether the waiting time has timed out. If the waiting time has timed out, the communication error is reported and the process proceeds to step S1006. If the waiting time has not timed out, the process returns to step S1005 and loops. S1006: turn off the Nth switch and send data N+1 to the upper computer; S1007: Determine whether the channel has been collected. If the channel has been collected, end the data collection and wait for the host computer instruction. If the channel has not been collected, return to step S1003; Wherein N is the number of gas paths of the gas valve, N≥1.

6. The multifunctional testing method for memory alloy according to claim 5, characterized in that: The range of N is 1 to 3.

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