CN116026417A - Multimode touch sensor based on magnetostriction inverse effect - Google Patents

Abstract

The invention relates to the technical field of tactile sensing, in particular to a multi-mode tactile sensor based on a magnetostriction inverse effect, which comprises a magnetostriction tactile sensor, a bending sensor and a temperature sensor, wherein the magnetostriction tactile sensor is used for identifying the hardness and the shape of an object, the bending sensor is used for identifying the size of the object, and the temperature sensor is used for identifying the temperature distribution of the object. The invention can sense the hardness, size, temperature and other information of the grabbing object, and realize the accurate identification and classification of the object through multi-mode information. The multi-mode touch sensor array is arranged on a mechanical finger, and objects with different hardness, size, shape and temperature are accurately identified and classified through signal analysis of the sensors.

Description

Multimode touch sensor based on magnetostriction inverse effect

Technical Field

The invention relates to the technical field of touch sensing, in particular to a multi-mode touch sensor based on magnetostriction inverse effect.

Background

In recent years, with the development of artificial intelligence technology, exploration of precise operation of robots is an important direction of future research. Haptic sensations are an irreplaceable source of information when humans explore the surrounding environment. It delivers a variety of sensory information to the central nervous system, such as pressure, vibration, and temperature, with advantages over vision in terms of material characteristics and detailed shape of the treatment target. With the continuous development of modern informatization, science and technology and industrialization, the emerging intelligent industry represented by robots is vigorous. It is expected that a bionic robot capable of replacing human work can be developed in the future. At present, the development characteristics and the trend of the robot technology are the interaction fusion of people and machines.

The touch sense is a form that human beings feel the external environment through the skin, and the robot touch sense mainly senses the physical quantities such as temperature, humidity, pressure, vibration and the like when the robot contacts with the external environment, and the information such as the softness degree of the material of a target object, the shape of the object, the size of the structure, the temperature and the like. The information acquired by a single sensor when measuring an object is too little, the intelligent robot can complete the measurement by precisely matching the sensors when working in a complex environment, and the attribute of the object can be more comprehensively ascertained by multi-azimuth and multi-mode sensing information. In order to make the operation of the manipulator more accurate, a multi-mode touch sensor needs to be installed on the manipulator to obtain the touch information such as the temperature, the size, the hardness and the like of the object, so that the object can be accurately identified and classified.

Disclosure of Invention

The present application is provided to solve the technical problems set forth in the background art. Therefore, a multi-mode touch sensor based on magnetostriction inverse effect is needed, a magnetostriction touch sensor is designed first, then the sensor is integrated with a temperature sensor and a bending sensor to form a multi-mode touch sensor array, the sensor can be placed on a mechanical finger to grab an object, and the hardness, shape, size, temperature and other information of the grabbed object can be perceived.

In order to solve the problems, the invention provides a multi-mode touch sensor based on magnetostriction inverse effect, which adopts the following technical scheme:

the utility model provides a multimode touch sensor based on magnetostriction inverse effect, includes magnetostriction touch sensor, crookedness sensor and temperature sensor, magnetostriction touch sensor discerns hardness, the shape of object, and crookedness sensor discerns the size of object's size, temperature sensor discerns the temperature distribution of object.

Further, 4 magnetostrictive tactile sensors and 2 temperature sensors form a 2x3 flexible composite sensor array, and then are combined with a bending sensor to form a multi-mode tactile sensor array based on the magnetostrictive inverse effect.

Further, the magnetostrictive tactile sensor comprises an iron gallium wire, a permanent magnet, a TMR sensor, a contact and a base; the permanent magnet is arranged on the upper side of the base, the TMR sensor is used as a signal acquisition unit and arranged at the lower end of the base to sense the change of surrounding magnetic fields and generate output voltage, the contact is used as a force sensing element and fixed on the top end of the iron gallium wire, one end of the iron gallium wire is connected with the TMR sensor, the other end of the iron gallium wire is connected with the contact, when the contact is applied with force in the vertical direction by the outside, the iron gallium wire is stressed to deform, the permanent magnet provides a bias magnetic field for the sensor, the magnetic domains in the iron gallium wire deflect according to the reverse magnetostriction effect, the magnetic induction intensity changes, and the TMR sensor outputs the magnetic induction intensity change in the iron gallium wire in a voltage signal mode through detecting the magnetic induction intensity change in the iron gallium wire.

Further, the temperature sensor comprises a thin film resistor, and the temperature-resistance characteristic relation of the thin film resistor is as follows:

R _T ＝R ₀ [1+aT-bT ₂ -cT ₃ (T-100)]

wherein R is _T Is warmResistance at degree T, R ₀ Is the resistance value at 0 ℃, T ₂ ＝100℃，T ₃ =200 ℃, a, b, c are coefficients.

Further, the bending sensor comprises a resistance sensing area, a sensing module and a microcontroller, wherein a signal output end of the resistance sensing area is connected with a signal input end of the sensing module, and a signal output end of the sensing module is connected with a signal input end of the microcontroller.

Further, the sensing area is formed by a resistor strip, the resistance value can be changed by different bending degrees, and the bending angle is judged according to the resistance change.

Further, the sensing module comprises a regulating circuit and an amplifying circuit which are sequentially connected, the regulating circuit converts resistance change into analog signals, the amplifying circuit amplifies the analog signals, and the microcontroller processes the signals and finally converts the signals into voltage signals.

Further, the multi-modal tactile sensor array is integrated on a flexible circuit board.

Further, the flexible circuit board is a double-layer board.

Further, the double-layer board has 6 connection units and 14 outputs, and of the 6 connection units, the connection unit connecting the magnetostrictive tactile sensor is composed of 5 pads, and the connection unit connecting the temperature sensor is composed of 2 pads.

The beneficial effects of the invention are as follows: according to the multi-mode touch sensor based on the magnetostriction inverse effect, the hardness, the size, the temperature and other information of the grabbing object can be perceived, and the accurate identification and classification of the object are realized through the multi-mode information. The multi-mode touch sensor array is arranged on a mechanical finger, and objects with different hardness, size, shape and temperature are accurately identified and classified through signal analysis of the sensors.

Drawings

In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. The same reference numerals with letter suffixes or different letter suffixes may represent different instances of similar components. The accompanying drawings illustrate various embodiments by way of example in general and not by way of limitation, and together with the description and claims serve to explain the disclosed embodiments. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Such embodiments are illustrative and not intended to be exhaustive or exclusive of the present apparatus or method.

FIG. 1 is a parameter of a temperature sensor;

FIG. 2 is a schematic view of a bending sensor;

FIG. 3 is a block diagram of a magnetostrictive tactile sensing unit;

FIG. 4 is a perspective view of a contact of the magnetostrictive tactile sensing unit;

FIG. 5 is a perspective view of a base of the magnetostrictive tactile sensing unit;

FIG. 6 is a perspective view of a multi-modal tactile sensor array based on the inverse effect of magnetostriction;

FIG. 7 is a top view of a circuit board of a multi-modal tactile sensor array based on the inverse effect of magnetostriction;

FIG. 8 is a static output characteristic of a magnetostrictive tactile sensing unit of a multi-modal tactile sensor based on the inverse effect of magnetostriction;

FIG. 9 is a graph of output voltage versus bending for a multi-modal tactile sensor based on the inverse effect of magnetostriction;

FIG. 10 is a calibration curve of a temperature sensor of a multi-modal tactile sensor based on the inverse effect of magnetostriction;

FIG. 11 is a sensor profile of a multi-modal tactile sensor array based on the inverse effect of magnetostriction;

FIG. 12 is a schematic diagram of the output voltage of the magnetostrictive tactile sensor array over time as a robot hand grabs a baseball in accordance with an embodiment of the present invention;

FIG. 13 is a schematic diagram of the output voltage of the bow sensing array over time when a robot grips a baseball in accordance with the teachings of the present invention;

FIG. 14 is a schematic diagram of the output voltage of the magnetostrictive tactile sensor array over time as a manipulator grabs a soft gel block according to an embodiment of the present invention;

FIG. 15 is a schematic diagram showing the change of the output voltage of the bending sensing unit with time when the manipulator grabs the soft rubber block according to the embodiment of the present invention;

FIG. 16 is a schematic representation of the output voltage of the magnetostrictive tactile sensor array over time as a manipulator grabs hot coffee in accordance with an embodiment of the present invention;

FIG. 17 is a schematic diagram of the output voltage of the bending sensing array as a manipulator grabs hot coffee as a function of time in accordance with an embodiment of the present invention;

FIG. 18 is a schematic diagram of the response of the temperature sensing unit when the manipulator is gripping four items in accordance with the teachings of the present invention;

FIG. 19 is a schematic view of the output voltage of the magnetostrictive tactile sensor array over time as the manipulator grabs mineral water in accordance with an embodiment of the present invention;

fig. 20 is a schematic view showing the change of the output voltage of the bending sensing array with time when the manipulator grips mineral water according to the embodiment of the present invention;

FIG. 21 is a schematic representation of the response of the temperature sensing array when the manipulator is gripping hot coffee in accordance with an embodiment of the present invention;

fig. 22 is a schematic diagram of a temperature sensing array response when a manipulator according to the present invention grips mineral water.

Detailed Description

Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict.

In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front," "rear," "head," "tail," and the like are used as an orientation or positional relationship based on that shown in the drawings, merely to facilitate description of the invention and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "connected," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

The following describes in further detail the embodiments of the present invention with reference to the drawings and examples.

The embodiment of the invention provides a multi-mode touch sensor based on a magnetostriction inverse effect, which comprises a magnetostriction touch sensor, a bending sensor and a temperature sensor, wherein the magnetostriction touch sensor is used for identifying the hardness and the shape of an object, the bending sensor is used for identifying the size of the object, and the temperature sensor is used for identifying the temperature distribution of the object.

The invention firstly designs a magnetostrictive tactile sensor which is used for sensing pressure distribution information of a grabbing object and identifying the hardness and shape of the object. The curvature is identified through the curvature sensor, so that the manipulator joint bending angle information is captured, and the manipulator joint bending angle information can be used for distinguishing the size of an object. The temperature sensor is used for sensing temperature information of the grabbed object. The multi-mode touch sensor based on the magnetostriction inverse effect is placed on the three-finger manipulator to grab different objects, the signal acquisition device is used for collecting and processing the objects, and the touch perception data and the machine learning are combined to accurately classify the different objects so as to help the manipulator to realize more complex perception functions and obtain more comprehensive information of the grabbed objects.

The magnetostrictive tactile sensor unit designed by the invention consists of a Fe-Ga wire, a permanent magnet, a TMR sensor, a contact and a base. The magnetostrictive tactile sensor can accurately sense static or dynamic force; the strip-shaped permanent magnet is used for applying a bias magnetic field to the iron gallium wire, and the magnetization inside the iron gallium wire has a certain initial value. When pressure is applied to the cylindrical contact, the iron gallium wire is stressed and bent to generate elastic deformation, so that the distribution of magnetic domains in the iron gallium wire is changed, and the magnetic induction intensity of the iron gallium wire is changed under the action of the inverse magnetostriction effect; the TMR element is used for converting the weak magnetic field change into magnetic resistance change through tunnel magnetic resistance effect, converting the magnetic resistance change into output voltage value through push-pull bridge circuit, collecting and processing the output voltage value of the sensing unit through the data acquisition card, and performing visualization processing in a computer display, wherein the characteristic of high sensitivity enables information detection of object properties to be more accurate.

In a specific embodiment, as shown in fig. 3, the magnetostrictive tactile sensor is composed of an iron-gallium-wire 1, a permanent magnet 2, a TMR sensor 3, a contact 4, and a base 5. The permanent magnet is placed on the upper side of the base, the TMR sensor is used as a signal acquisition unit and is arranged at the lower end of the base to sense the change of surrounding magnetic fields and generate output voltage, the contact is used as a force sensing element and is fixed on the top end of the iron gallium wire, one end of the iron gallium wire is connected with the TMR sensor, the other end of the iron gallium wire is connected with the contact, when the contact is externally applied with force in the vertical direction, the iron gallium wire is stressed to deform, the permanent magnet provides a bias magnetic field for the sensor, the magnetic domains in the iron gallium wire are deflected according to the inverse magnetostriction effect, the magnetic induction intensity is changed, and the TMR sensor outputs the magnetic induction intensity change in the iron gallium wire in a voltage signal mode by detecting the change of the magnetic induction intensity. The magnetostrictive tactile sensor has the characteristics of high sensitivity, high response speed and high integration level.

The magnetostrictive tactile sensing unit adopts three iron-gallium wires with the diameter of 0.5mm and the length of 6 mm. The permanent magnet is cuboid, is made of neodymium iron boron, has the length of 4mm, the width of 1mm, the height of 0.5mm and the magnetic field strength of 11.97kA/m, and ensures that the output signal of TMR is in a linear interval. The upper part of the contact (shown in figure 4) is a cylinder, the diameter of the circle is 4mm, the thickness of the contact is 1mm, 3 parallel round holes with the distance of 1mm and the diameter of 0.5mm are drilled at the position of 0.2mm away from the bottom, the iron gallium wire passes through the round holes, the tail part of the iron gallium wire is attached to the magneto-sensitive part of the TMR sensor, the pressure is applied to the contact, and the pressure is transmitted to the iron gallium wire through the contact. The base (as shown in fig. 5) is a cuboid, a cuboid groove is formed in the base, 3 round holes with the diameter of 0.5mm are formed in the base, and a TMR sensor and 3 iron-gallium wires with the diameter of 0.5mm are respectively placed in the base. The contact and the base are made of resin. The TMR used was 3mm in length, 2.8mm in width and 1.45mm in height, and model number TMR2003. Magnetostrictive sensor cell dimensions were 8mm long, 4mm wide and 2.5mm high. The magnetostrictive tactile sensor units are made into a 2x2 array, the distance between the unit 1 and the unit 2 is 4mm, and the distance between the unit 1 and the unit 3 is 14mm, so that the interference degree of each unit is reduced, and the magnetic coupling signals are reduced. The external force makes the iron gallium wire bend and deform through the contact, and causes the internal magnetic domain to change. The change of magnetic induction intensity of the iron-gallium wire can change the internal magnetic resistance of the TMR sensor, and then the internal magnetic resistance is converted into a voltage signal through a bridge circuit. The sensing part and the measuring part detect a relationship between a pressure externally applied to the tactile sensor and an output voltage.

The temperature sensor designed by the invention is based on a thin film resistor, and the size is 2.3mm x2.1mm x0.9mm. The resistance value of metallic platinum (Pt) varies with temperature change, and has excellent reproducibility and stability, and a sensor made by using such physical characteristics of platinum is called a platinum resistance temperature sensor, and is commonly referred to as Pt. It is a positive temperature coefficient resistor, i.e. the resistor increases as the temperature increases. The platinum resistance temperature sensor has high precision, good stability and wide application temperature range, is the most commonly used temperature detector in a medium-low temperature area (-200-600 ℃), is widely applied to industrial temperature measurement, and is manufactured into various standard thermometers (covering national and world reference temperatures) for metering and calibration. FIG. 6 shows a calibration curve of a temperature sensor, which has good consistency in response characteristics and meets the accuracy requirement of the experiment, the response time is set to be tau=0.5 s, and the response time of the sensor in direct contact with an object is within 8s, the temperature-resistance characteristic relationship is that

R _T ＝R ₀ [1+aT-bT ₂ -cT ₃ (T-100)]

Wherein R is _T R is the resistance at temperature T ₀ The resistance at 0 ℃ is t2=100 ℃, t3=200 ℃, a, b and c are coefficients, and the maximum temperature drift of the PT-1000 temperature sensor is 0.02 ℃ as shown in fig. 1.

The bending sensor is a device for measuring bending angle, and is usually composed of a variable resistor, covered on the surface of Flex, and reacts to bending, different bending changes the resistance value of the sensor, and the bending angle can be judged according to the resistance change of the sensor.

As shown in fig. 2, the bending sensor is composed of a resistance sensing area, a sensing module and a microcontroller. The size of the induction area is 77mmx6.35mm, the induction area is composed of resistance strips, the resistance value can be changed by different bending degrees, and the bending angle can be judged according to the resistance change. The size of the sensing module is 43.54mmx12.50mm, and the sensing module consists of a regulating circuit and an amplifying circuit, wherein the regulating circuit can convert resistance change into an analog signal, the amplifying circuit amplifies the analog signal, and the microcontroller processes the signal and finally converts the signal into a voltage signal.

In a specific embodiment, the multi-mode touch sensor based on the magnetostriction inverse effect is a 2x3 flexible composite sensor array formed by 4 magnetostriction touch sensing units and 2 temperature sensors, and then combined with the bending sensor to form the multi-mode touch sensor array based on the magnetostriction inverse effect. As in fig. 6, units 1, 2, 3, 4 are magnetostrictive tactile sensors, units 5 and 6 are temperature sensors, and the multi-sensor array is integrated on a flexible circuit board (as in fig. 7). The circuit board adopts the bilayer board, has 6 connecting elements and 14 outputs, and U1, U2, U3, U4 are magnetostriction touch sensor respectively, and every connecting element comprises 5 bonding pads: v-, GND, VCC, NA, V +; u5 and U6 are temperature sensor units, each connecting unit is composed of 2 bonding pads, and 14 output ends of the positive electrode and the negative electrode of the temperature sensor are GND, R2-, R1-, V4-, V3-, V2-, V1-, R2+, R1+, V4+, V3+, V2+, V1 and VCC respectively from top to bottom.

The following examples of the present invention will further demonstrate the feasibility and advancement of the invention in conjunction with specific experiments.

Experimental example 1: the input-output relationship of the magnetostrictive tactile sensor was studied.

Building an experiment platform: the installed sensor is fixed on an experiment table, a direct-current stabilized power supply is used as a power supply, digital display push-pull force meters apply static forces with different magnitudes to the sensing units, output voltages of the magnetostrictive tactile sensors are collected on a computer through a data acquisition card, and corresponding curves are drawn.

Experimental procedure and results: the static force of 0-3N is displayed by a digital push-pull force meter, the force is removed after 3 seconds, as shown in FIG. 8, the static output characteristic of the magnetostrictive tactile sensing unit is shown, the output voltage of the sensor and the pressure are in a linear relation within 0-3N, the maximum sensitivity is 296.5mV/N, when the applied pressure is 3N, the output voltage of the sensor is 919.5mV, and the experimental value is basically consistent with the theoretical value.

Experimental example 2: the relationship between the bending sensor and the voltage was studied.

After the sensor is calibrated, the curvature sensor is placed on the manipulator, the direct current voltage stabilizing source is used as a power supply, repeated bending experiments are carried out on the sensor within the range of 0-100 degrees (step length of 10 degrees), data are acquired through the data acquisition device, the relation between the output voltage and the curvature of the sensor is obtained, as shown in fig. 9, and the approximately linear relation between the output voltage and the curvature can be seen.

Experimental example 3: the relationship between the resistance and the temperature of the temperature sensor was studied.

Building an experiment platform: the temperature sensor is heated by a heater and the resistance value of the temperature sensor is recorded using a multimeter.

Experimental procedure and results: heating the temperature sensor by the heating device in the range of 0-100 ℃ (step length 5 ℃), measuring and recording the resistance values of the temperature sensor at different temperatures by a universal meter, and drawing a curve of the resistance and the temperature, wherein the PT-1000 film resistance is a positive temperature coefficient resistance, namely the resistance increases when the temperature rises, as shown in fig. 10.

Experimental example 4: research on object grabbing experiments of multi-mode sensor array

Building an experiment platform: the sensor array is placed on a three-finger manipulator, 4 objects are grabbed, 4 objects such as baseball, silica gel blocks, mineral water bottles and hot coffee are grabbed by supplying power through a direct-current voltage stabilizing source, the output end of the sensor is input into a computer through a data acquisition card for acquisition, and a relevant curve is drawn through the computer.

Experimental procedure and results: the sensor array is placed on the three-finger manipulator, the sensor arrangement is shown in fig. 11, and the grabbing angle and grabbing position of the three-finger manipulator are adjusted, so that the multi-mode touch sense sensing array installed on the surface of the finger bone of the manipulator can grab objects in a fitting manner, and each unit in the array is guaranteed to have output. The controller controls the mechanical arm to grasp baseball, soft rubber block, hot coffee and ice mineral water respectively, and the output voltage of the magnetostrictive tactile sensor is U _1， The sensor units 1, 2, 3 and 4 are magnetostriction touch sensors capable of reflecting the hardness and shape of the object, and the object is classified by different and changing conditions of output voltages; the units 5 and 6 are temperature sensors by means of which the temperature of the object can be reflected and by means of which the rough temperature profile of the object can also be obtained. The output voltage of the bending sensor is U ₂ The bending angle changes with the change of the size of the object, and the output voltage of the bending sensor can reflect the size of the object. Through the distribution of the sensors, the three-finger manipulator has 12 magnetogenerators in totalThe telescopic sensing units are numbered as tactile sensor units 1, 2, 4, 5, 6, 7, 8, 9, 10, 11 and 12 respectively; a total of 3 bending sensor units 1, 2, 3; a total of 6 temperature sensing units 1, 2, 3, 4, 5, 6; placing 4 kinds of objects at fixed positions, controlling the manipulator through the controller until the manipulator stably grabs the objects, and then stably grabbing for 2s and loosening; the output voltage of the magnetostrictive tactile sensor unit rapidly rises in the process of grabbing an object by the manipulator, after the stable grabbing state is reached, the output voltage is kept at a maximum value, and after the object is loosened, the voltage is restored to an initial state, so that a time-varying curve of the tactile sensor unit can be obtained, such as a time-varying schematic diagram 12 of the output voltage of the magnetostrictive tactile sensor array when grabbing baseball, a time-varying schematic diagram 14 of the output voltage of the magnetostrictive tactile sensor array when grabbing soft rubber blocks, a time-varying schematic diagram 16 of the output voltage of the magnetostrictive tactile sensor array when grabbing hot coffee, a time-varying schematic diagram 19 of the output voltage of the magnetostrictive tactile sensor array when grabbing mineral water, and the shape difference of the object can be judged according to the output number, the output voltage value and the unit position of the magnetostrictive tactile sensor array 12, and the hardness of the grabbed object can be judged according to the maximum output voltage of the magnetostrictive sensor unit. The curvature sensor rapidly drops in the process of grabbing objects, after the stable grabbing state is reached, the output voltage is basically kept unchanged, and after the objects are loosened, the voltage is restored to the initial state, so that a curve of the curvature sensor unit changing along with time can be obtained, such as a schematic diagram 13 of the change along with time of the output voltage of the curvature sensor array when the manipulator grabs baseball, a schematic diagram 15 of the change along with time of the output voltage of the curvature sensor array when the manipulator grabs soft rubber blocks, a schematic diagram 17 of the change along with time of the output voltage of the curvature sensor array when the manipulator grabs hot coffee, a schematic diagram 20 of the change along with time of the output voltage of the curvature sensor array when the manipulator grabs mineral water, the smaller the object size is, the greater the bending degree is, and the lower the output voltage is. The schematic diagram 18 of the response of the temperature sensing characteristic unit when the manipulator grabs four objects can be obtained through the output of the temperature sensor, and the temperature sensing array when the manipulator grabs hot coffee can be obtainedSchematic of column response 21 and temperature sensing array response when grasping mineral water fig. 22. The multi-mode touch sensor array can acquire multiple characteristics of pressure, temperature and bending of the grabbed object, so that the object can be accurately classified.

The above embodiments are only for illustrating the present invention, not for limiting the present invention, and various changes and modifications may be made by one of ordinary skill in the relevant art without departing from the spirit and scope of the present invention, and therefore, all equivalent technical solutions are also within the scope of the present invention, and the scope of the present invention is defined by the claims.

Claims (10)

1. The multi-mode touch sensor based on the magnetostriction inverse effect is characterized by comprising a magnetostriction touch sensor, a bending sensor and a temperature sensor, wherein the magnetostriction touch sensor is used for identifying the hardness and the shape of an object, the bending sensor is used for identifying the size of the object, and the temperature sensor is used for identifying the temperature distribution of the object.

2. The magnetostrictive inverse effect based multi-modal tactile sensor as defined in claim 1 wherein 4 magnetostrictive tactile sensors and 2 temperature sensors form a 2x3 flexible composite sensor array and then combined with the bending sensor to form the magnetostrictive inverse effect based multi-modal tactile sensor array.

3. The magnetostrictive inverse effect based multi-modal tactile sensor according to claim 1 or 2, wherein the magnetostrictive tactile sensor comprises a iron gallium wire, a permanent magnet, a TMR sensor, a contact and a base; the permanent magnet is arranged on the upper side of the base, the TMR sensor is used as a signal acquisition unit and arranged at the lower end of the base to sense the change of surrounding magnetic fields and generate output voltage, the contact is used as a force sensing element and fixed on the top end of the iron gallium wire, one end of the iron gallium wire is connected with the TMR sensor, the other end of the iron gallium wire is connected with the contact, when the contact is applied with force in the vertical direction by the outside, the iron gallium wire is stressed to deform, the permanent magnet provides a bias magnetic field for the sensor, the magnetic domains in the iron gallium wire deflect according to the reverse magnetostriction effect, the magnetic induction intensity changes, and the TMR sensor outputs the magnetic induction intensity change in the iron gallium wire in a voltage signal mode through detecting the magnetic induction intensity change in the iron gallium wire.

4. The magnetostrictive inverse effect based multi-modal tactile sensor according to claim 1 or 2, wherein the temperature sensor comprises a sheet resistance having a temperature-resistance characteristic relationship of:

R _T ＝R ₀ [1+aT-bT ₂ -cT ₃ (T-100)]

wherein R is _T R is the resistance at temperature T ₀ Is the resistance value at 0 ℃, T ₂ ＝100℃，T ₃ =200 ℃, a, b, c are coefficients.

5. The multi-modal tactile sensor based on the inverse magnetostrictive effect according to claim 1 or 2, wherein the bending sensor comprises a resistive sensing area, a sensing module and a microcontroller, wherein the signal output end of the resistive sensing area is connected with the signal input end of the sensing module, and the signal output end of the sensing module is connected with the signal input end of the microcontroller.

6. The multi-modal tactile sensor based on the inverse magnetostrictive effect of claim 5 wherein the sensing area is formed of resistive strips, different curvatures change resistance values, and the bending angle is determined based on the resistance change.

7. The multi-modal tactile sensor based on the inverse magnetostrictive effect according to claim 6, wherein the sensing module comprises a conditioning circuit and an amplifying circuit connected in sequence, the conditioning circuit converting the resistance change to an analog signal, the amplifying circuit amplifying the analog signal, the microcontroller processing the signal and finally converting to a voltage signal.

8. The magnetostrictive inverse effect based multi-modal tactile sensor of claim 2 wherein the multi-modal tactile sensor array is integrated on a flexible circuit board.

9. The magnetostrictive inverse effect based multi-modal tactile sensor of claim 8, wherein the flexible circuit board is a two-layer board.

10. The magnetostrictive inverse effect based multi-modal tactile sensor as defined in claim 9 wherein the bi-laminate has 6 connection units and 14 outputs, the connection unit connecting the magnetostrictive tactile sensor consisting of 5 pads and the connection unit connecting the temperature sensor consisting of 2 pads.

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