JP2014098687A - Tactile sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To resolve a drawback of a conventional tactile sensor by forming a single layer elastomer which does not need lamination and contains magnetic fillers, and in which the magnetic fillers are not distributed uniformly but distributed unevenly skewed in one surface side.SOLUTION: There is provided a tactile sensor which is composed of an elastomer containing magnetic fillers, and a magnetic sensor for detecting magnetic change caused by deformation of the elastomer due to touch for sensing. The magnetic fillers are unevenly distributed, and the maldistribution degree is in a range of 1 to 100.

Description

  The present invention relates to a tactile sensor that detects deformation caused by contact with an elastomer containing a magnetic filler, and more particularly to a tactile sensor in which a magnetic filler is unevenly distributed in the elastomer.

  Tactile sensors are widely used in various fields. Basically, when a certain object comes into contact with another object, the strength, position, direction, etc. of the contact are detected. The tactile sensor is applied to, for example, the robot's hand and skin, and is used as information to determine the next action of the robot. Further, it detects the seating state for automobiles, detects the surface pressure distribution for beds and carpets, and detects the collision state for vehicles. It is used for detecting the motion state of a living body (for example, motion capture, detecting the biological motion of a breathing state or a relaxed state of a muscle), detecting illegal entry into a restricted access area, detecting a foreign object in a sliding door, and a keyboard input device.

  Japanese Patent Application Laid-Open No. 2009-229453 (Patent Document 1) discloses a pressure detection device including a buffer unit that includes a magnet and is deformed by pressurization and a sensor unit that detects a change in a magnetic field accompanying the deformation of the buffer unit by a magnetic sensor. Is described. The magnet present in the buffer portion of the pressure detection device may be a single large magnet (FIG. 1 in Patent Document 1), or small magnets may be uniformly dispersed (see FIG. 7 in Patent Document 1, etc.). In the case of a single large magnet, it is difficult to detect deformation caused by tactile sensation, and a foreign object sensation occurs when touched. If small magnets are evenly distributed, even if the direction of the magnetic force is the same, a phenomenon occurs in which the magnetic force cancels out between the magnet particles, and the magnet near the contact surface moves, but the internal magnet Is difficult to move, and the detection sensitivity deteriorates when the external force is small and the deformation is very small.

  Japanese Patent Laid-Open No. 2008-39659 (Patent Document 2) discloses a viscoelastic magnet obtained by kneading and forming a magnet raw material and a viscoelastic material, and a magnetic flux detecting means for detecting a change in magnetic flux density vector due to deformation of the viscoelastic magnet. An apparatus is described. In the detection device of Patent Document 2, since the magnet raw material is kneaded in the viscoelastic material, the magnet raw material is uniformly dispersed. As described in Patent Document 1, the magnetic forces cancel each other between the magnet particles. The phenomenon occurs, and the magnet particles near the contact surface move, but the internal magnet particles are difficult to move, and the detection sensitivity deteriorates when the external force is small and the deformation is very small.

  Japanese Patent Application Laid-Open No. 62-46222 (Patent Document 3) includes a magnetic sensor, an elastomer and a permanent magnet that are sequentially laminated and fixed on the magnetic sensor, and lead wires connected to input / output terminals of the magnetic sensor. A pressure sensitive sensor is disclosed. In this pressure-sensitive sensor, the elastic material and the magnet-containing material are separated from each other, and it is necessary to “sequentially laminate and fix” them, and a lamination process is required. It can happen.

JP 2009-229453 A JP 2008-39659 A JP-A-62-46222

  In the present invention, an elastomer containing a single-layer magnetic filler that does not require lamination is formed, and the magnetic filler is not uniformly dispersed, but is unevenly distributed on one surface side. The purpose is to eliminate the drawbacks of tactile sensors.

That is, the present invention includes an elastomer containing a magnetic filler,
A magnetic sensor for detecting a magnetic change caused by tactile deformation of the elastomer;
The tactile sensor is characterized in that the magnetic filler is unevenly distributed in the elastomer, and the uneven distribution degree is 1 to 100.

  The magnetic filler is preferably unevenly distributed on one side of the elastomer, and the unevenly distributed surface may be used as a contact surface.

  Preferably, the magnetic filler is a rare earth-based, Fe-based, Co-based, Ni-based, or oxide-based material with an average particle size of 0.02 to 500 μm.

  Further, the magnetic filler is preferably added in an amount of 1 to 450 parts by weight with respect to 100 parts by weight of the elastomer.

  Furthermore, the elastomer is preferably a polyurethane elastomer or a silicone elastomer.

  According to the tactile sensor of the present invention, the magnetic filler is not uniformly dispersed in the elastomer but is unevenly distributed, and the uneven distribution degree is limited to 1 to 100, so that the magnetic force cancels between the magnetic fillers. Since there are many magnetic fillers in the vicinity of the contact surface, a large number of magnetic fillers are displaced even with a small external force. Therefore, even when the external force is small and the deformation is very small, detection with a magnetic sensor becomes easy.

  In addition, since the elastomer and the magnetic filler-containing material are not separated in the tactile sensor of the present invention, inexpensive and easy production can be achieved without causing separation between layers. Note that the magnetic filler is unevenly distributed by mixing the magnetic filler and the elastomer raw material, and then allowing to stand for a predetermined time, or if the magnetic filler is already magnetized, the magnet is placed on one side during mixing. Since uneven distribution occurs due to the attractive force of the magnet, the manufacturing process is simple and easy, and there is no complication due to unnecessary increase in operation. Of course, a method other than the above, for example, a method of performing uneven distribution by performing a centrifugal treatment is also conceivable.

It is a mimetic diagram showing the section of the tactile sensor of the present invention, and typically shows change when there is no pressure and when pressure is added.

Definition of terms

  In this specification, “the degree of uneven distribution” is a numerical value representing the degree of uneven distribution of the magnetic filler in the elastomer, and is measured by the following method. The produced elastomer was cut out with a razor blade, and the cross section of the sample was observed with a digital microscope at 100 times. The obtained image was divided into three equal parts in the thickness direction of the elastomer using image analysis software (WinROOF manufactured by Mitani Corporation), and the number of magnetic filler particles in the upper, middle and lower layers was counted. By determining the ratio between the number of particles in each layer and the number of particles in the middle layer, the magnetic filler abundance of each layer was determined. Furthermore, the degree of uneven distribution was determined by obtaining [magnetic filler abundance ratio of upper layer] − [magnetic filler abundance ratio of lower layer]. Here, the upper layer is a layer on the contact surface side in the tactile sensor. The higher the value of the degree of uneven distribution, the magnetic filler is unevenly distributed.

The present invention will be described with reference to FIG.
FIG. 1 is a schematic diagram showing a cross section of the tactile sensor of the present invention, and schematically shows a change when there is no pressure (left side in FIG. 1) and when pressure is applied (right side in FIG. 1).

  The tactile sensor of the present invention basically comprises an elastomer 1 and a magnetic sensor 2. The elastomer 1 contains a large amount of the magnetic filler 3, and in the present invention, the magnetic filler 3 is unevenly distributed upward in the figure, and the uneven distribution degree is 1 to 100. In FIG. 1, a substrate 4 exists between the elastomer 1 and the magnetic sensor 2. The substrate 4 may be omitted, but is usually necessary to support the elastomer 1. Further, if the substrate 4 is not present, when the pressure 5 is applied to the elastomer 1, the entire elastomer 1 is bent, and the pressure 5 may not be detected accurately.

  On the left side of FIG. 1, no pressure is applied, but on the right side of FIG. 1, pressure 5 is applied from above the elastomer 1. Due to the pressure 5, the elastomer 1 is deformed, and the position of the magnetic filler 3 is lowered downward by the portion where the pressure is applied. This downward change of the magnetic filler 3 changes the magnetic field emitted from the magnetic filler 3 and is detected by the magnetic sensor 2.

  If the pressure 5 is a strong force, the change in the position of the magnetic filler 3 will be large. Conversely, if the pressure 5 is small, the change in the position of the magnetic filler 3 will be small. can do. Further, when the pressure 5 is straight upward, it can be detected by one magnetic sensor, but pressure from an oblique direction can also be detected by optimizing the number and arrangement of the magnetic sensors.

  The magnetic filler 3 is preferably unevenly distributed on one side of the elastomer 1, and the unevenly distributed surface is preferably a contact surface. In the embodiment shown in FIG. 1, the unevenly distributed surface is a contact surface. This aspect increases the displacement of the magnetic filler 3 and facilitates detection.

  The degree of uneven distribution of the magnetic filler 3 is determined by measurement as in the definition of the above term. The uneven distribution degree is 1 to 100, preferably 2 to 90, more preferably 3 to 80. When the degree of uneven distribution is smaller than 1, the magnetic filler is not very unevenly distributed in the elastomer, and as described in the prior art, the cancellation of magnetic force and the displacement of the magnetic filler inside the elastomer are small. Detection with a sensor may be difficult. On the contrary, an uneven distribution degree of 100 is preferable because almost all of the magnetic filler is present on the contact surface of the elastomer, but in practice, it is almost 100 or less.

  The magnetic filler 3 generally includes rare earths, irons, cobalts, nickels, and oxides, but any of these may be used. Preferably, it is a rare earth system that can obtain a high magnetic force, but is not limited thereto. The shape of the magnetic filler 3 is not particularly limited, and may be any of a spherical shape, a flat shape, a needle shape, a columnar shape, and an indefinite shape. The magnetic filler has an average particle size of 0.02 to 500 μm, preferably 0.1 to 400 μm, more preferably 0.5 to 300 μm. When the average particle size is smaller than 0.02 μm, the magnetic properties of the magnetic filler are deteriorated. When the average particle size exceeds 500 μm, the mechanical properties (brittleness) of the magnetic elastomer are deteriorated.

  The magnetic filler 3 may be introduced into the elastomer after magnetization, but is usually magnetized after being introduced into the elastomer. When magnetized after being introduced into the elastomer, the directions of the magnets are aligned as shown in FIG. 1, and the detection of the magnetic force is facilitated.

  A general elastomer can be used as the elastomer 1, but a thermosetting elastomer is preferable in consideration of characteristics such as compression set. It is necessary to stir after introducing the magnetic filler into the elastomer, and then to disperse the magnetic filler. Normally, when the magnetic filler is introduced and allowed to stand at room temperature or a predetermined temperature, it settles down due to the weight of the magnetic filler, and the magnetic filler is unevenly distributed on the lower surface. Further, uneven distribution may be performed using a physical force such as centrifugal force or magnetic force.

  The elastomer 1 is preferably a polyurethane elastomer or a silicone elastomer. In the case of a polyurethane elastomer, an active hydrogen-containing compound, a solvent, and a magnetic filler are mixed, and a mixed liquid is obtained by mixing an isocyanate component therein. Moreover, a liquid mixture can also be obtained by mixing an isocyanate component with a solvent and a filler and mixing an active hydrogen-containing compound. The mixed liquid is poured into a mold that has been subjected to a mold release treatment, and then left to stand for a predetermined period of time so as to be unevenly distributed by sedimentation of the magnetic filler, and then heated to a curing temperature and cured to form an elastomer. . In the case of a silicone elastomer, a solvent and a magnetic filler are mixed in a precursor of a silicone elastomer, and when placed in a mold, the mixture is allowed to stand and unevenly distributed, and then heated and cured to form the elastomer.

  Here, the following are mentioned about the isocyanate component and active hydrogen containing compound which can be used in the case of a polyurethane elastomer.

  As the isocyanate component, a known compound in the field of polyurethane can be used without particular limitation. As the isocyanate component, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,2′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, aromatic diisocyanates such as p-phenylene diisocyanate, m-phenylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, ethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 1,6-hexamethylene diisocyanate, etc. Aliphatic diisocyanate, 1,4-cyclohexane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate Isocyanate, alicyclic diisocyanates such as norbornane diisocyanate. These may be used alone or in combination of two or more. The isocyanate may be modified by urethane modification, allophanate modification, biuret modification, isocyanurate modification or the like.

  Examples of the active hydrogen-containing compound include those usually used in the technical field of polyurethane. Examples include polyether polyols typified by polytetramethylene ether glycol, polyethylene glycol, etc., polyester polyols typified by polybutylene adipate, polycaprolactone polyols, reactants of polyester glycols such as polycaprolactone and alkylene carbonate, etc. Polyester polycarbonate polyol, Polyester polyol obtained by reacting ethylene carbonate with polyhydric alcohol and then reacting the resulting reaction mixture with organic dicarboxylic acid, Polycarbonate polyol obtained by transesterification of polyhydroxyl compound and aryl carbonate Etc. These may be used alone or in combination of two or more.

  In addition to the high molecular weight polyol component described above as the active hydrogen-containing compound, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, diethylene glycol, triethylene glycol, 1,4-bis (2-hydroxyethoxy) benzene, trimethylolpropane, glycerin, 1,2,6- Hexanetriol, pentaerythritol, tetramethylolcyclohexane, methylglucoside, sorbitol, mannitol, dulcitol, sucrose, 2,2,6,6-tetrakis (hydroxymethyl) cyclohexanol, and triethanolamine Low molecular weight polyol component equal, ethylenediamine, tolylenediamine, diphenylmethane diamine, may be used low molecular weight polyamine component of diethylenetriamine. These may be used alone or in combination of two or more. Furthermore, 4,4′-methylenebis (o-chloroaniline) (MOCA), 2,6-dichloro-p-phenylenediamine, 4,4′-methylenebis (2,3-dichloroaniline), 3,5-bis ( Methylthio) -2,4-toluenediamine, 3,5-bis (methylthio) -2,6-toluenediamine, 3,5-diethyltoluene-2,4-diamine, 3,5-diethyltoluene-2,6- Diamine, trimethylene glycol-di-p-aminobenzoate, polytetramethylene oxide-di-p-aminobenzoate, 1,2-bis (2-aminophenylthio) ethane, 4,4'-diamino-3,3 ' -Diethyl-5,5'-dimethyldiphenylmethane, N, N'-di-sec-butyl-4,4'-diaminodiphenylmethane, 4,4'-diamy −3,3′-diethyldiphenylmethane, 4,4′-diamino-3,3′-diethyl-5,5′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diisopropyl-5,5′- Dimethyldiphenylmethane, 4,4′-diamino-3,3 ′, 5,5′-tetraethyldiphenylmethane, 4,4′-diamino-3,3 ′, 5,5′-tetraisopropyldiphenylmethane, m-xylylenediamine, Polyamines exemplified by N, N′-di-sec-butyl-p-phenylenediamine, m-phenylenediamine, p-xylylenediamine and the like can also be mixed.

  The amount of the magnetic filler in the elastomer is 1 to 450 parts by weight, preferably 2 to 400 parts by weight with respect to 100 parts by weight of the elastomer. If the amount is less than 1 part by weight, it is difficult to detect a change in the magnetic field. On the other hand, when the amount exceeds 450 parts by weight, desired characteristics cannot be obtained, for example, the elastomer itself becomes brittle.

  The magnetic sensor 2 may be any sensor that is normally used for detecting a change in a magnetic field, and may be a magnetoresistive element (for example, a semiconductor compound magnetoresistive element, an anisotropic magnetoresistive element (AMR), a giant magnetoresistive element (GMR)). ) Or tunnel magnetoresistive element (TMR)), Hall element, inductor, MI element, fluxgate sensor, and the like. From the viewpoint of sensitivity, a Hall element is preferably used.

  The present invention will be described in more detail with reference to examples. The present invention is not limited to these examples.

  Into a reaction vessel, 40 parts by weight of polypropylene glycol (Asahi Glass Co., Ltd., Preminol 7001, number average molecular weight 6000) and 60 parts by weight of polypropylene glycol (Asahi Glass Co., Ltd., Exenol 3020, number average molecular weight 3000) are put, and dehydration under reduced pressure is performed. Went for hours. Thereafter, the inside of the reaction vessel was purged with nitrogen. Next, 10 parts by weight of tolylene diisocyanate (mixture of Mitsui Chemicals, TDI-80, 2,4-isomer / 2,6-isomer = 80/20) was added to the reaction vessel, and the temperature in the reaction vessel was adjusted. An isocyanate-terminated prepolymer was synthesized by reacting for 5 hours while maintaining at 80 ° C.

  Next, 33 parts by weight of polypropylene glycol (Asahi Glass Co., Ltd., preminol 7001, number average molecular weight 6000), 8 parts by weight of polypropylene glycol (Asahi Glass Co., Ltd. Exenol 1020, number average molecular weight 1000), lead octylate (Toei Chemical) A mixed solution of 0.06 parts by weight, 100 parts by weight of magnetic filler (MF-15P neodymium-based magnetic substance powder manufactured by Aichi Steel Corporation, average particle size 133 μm) and 120 parts by weight of toluene as a diluent was degassed under reduced pressure. Similarly, 59 parts by weight of the isocyanate-terminated prepolymer was degassed under reduced pressure while being heated to 80 ° C. Next, the mixed solution and the prepolymer were mixed and defoamed with a hybrid mixer (manufactured by Keyence Corporation). This reaction solution was poured into a mold subjected to a release treatment, and a polyethylene terephthalate film subjected to a release treatment was placed thereon, and the thickness was adjusted to 1 mm with a nip roll. Then, the magnetic filler was settled by leaving still for 120 minutes at normal temperature as a magnetic filler uneven distribution process. Thereafter, the mold was placed in an oven at 80 ° C. and cured for 1 hour to obtain a urethane elastomer. The resulting elastomer sheet was magnetized at 1.3 T with a magnetizing device (manufactured by Electronic Magnetic Industry Co., Ltd.) to obtain a polyurene elastomer.

  Using the polyurethane elastomer, the degree of uneven distribution was measured according to the following uneven degree evaluation. Further, using a Hall element as the magnetic sensor, the characteristics of the tactile sensor were performed according to the following tactile sensor characteristics evaluation. The results are shown in Table 1. Regarding the uneven distribution degree, the uneven distribution processing time is also described in Table 1.

Evaluation of uneven distribution The produced elastomer was cut out with a razor blade, and the sample cross section was observed with a digital microscope at 100 times. The obtained image was divided into three equal parts in the thickness direction of the elastomer using image analysis software (WinROOF manufactured by Mitani Corporation), and the number of magnetic filler particles in the upper, middle and lower layers was counted. By determining the ratio between the number of particles in each layer and the number of particles in the middle layer, the magnetic filler abundance of each layer was determined. Furthermore, the degree of uneven distribution was determined by obtaining [magnetic filler abundance ratio of upper layer] − [magnetic filler abundance ratio of lower layer]. Here, the upper layer is a layer on the contact surface side in the tactile sensor.

Tactile sensor characteristic evaluation A hall element (EQ-430L manufactured by Asahi Kasei Electronics Co., Ltd.) is installed on the substrate as a magnetic sensor, and an elastomer is installed on the surface opposite to the substrate as shown in FIG. At this time, the elastomer is installed so that the surface on which the magnetic filler is unevenly distributed becomes the contact surface. Tactile sensor characteristics were obtained by reading the output voltage at a predetermined load with a compression tester (Shimadzu Autograph). Further, the sensor characteristic was evaluated by using the output voltage change rate (ΔVout) of the Hall element when the pressure of 30 kPa was applied as the sensor sensitivity.

  A urethane elastomer was obtained in the same manner as in Example 1 except that SmFeN alloy fine powder manufactured by Sumitomo Metal Mining Co., Ltd., samarium-based magnetic powder, and average particle size of 2.5 μm were used as the magnetic filler.

  Using the obtained urethane elastomer, the degree of uneven distribution and sensor sensitivity were measured in the same manner as in Example 1. The results are shown in Table 1.

  A reaction vessel was charged with 50 parts by weight of a silicone precursor (DY-1106A: manufactured by Toray Dow Corning), 100 parts by weight of a magnetic filler, and 60 parts by weight of toluene, followed by stirring and degassing at room temperature for 60 minutes. 60 parts by weight of toluene was added to 50 parts by weight of another silicone precursor (DY-1106B: manufactured by Toray Dow Corning), and the mixture was stirred and defoamed under reduced pressure for 60 minutes. . This reaction solution was dropped onto a mold subjected to a release treatment, and a polyethylene terephthalate film subjected to a release treatment was placed thereon, and the thickness was adjusted to 1 mm with a nip roll. Thereafter, the magnetic filler was allowed to settle for 120 minutes at room temperature as a magnetic filler uneven distribution treatment. Thereafter, the mold was placed in an oven at 120 ° C., cured for 15 minutes, and further cured at 200 ° C. for 4 hours to obtain a silicone elastomer.

  The obtained silicone elastomer sheet was magnetized at 1.3 T with a magnetizing device (manufactured by Electronic Magnetic Industry Co., Ltd.) to obtain a silicone elastomer.

  Using the obtained silicone elastomer, the degree of uneven distribution and sensor sensitivity were measured in the same manner as in Example 1. The results are shown in Table 1.

  Using the same raw material as in Example 3, 60 parts by weight of toluene was allowed to stand as a magnetic filler uneven distribution treatment at room temperature for 60 minutes to obtain a silicone elastomer having a changed magnetic filler uneven distribution degree.

  Using the obtained silicone elastomer, the degree of uneven distribution and sensor sensitivity were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1

  Using the same raw material as in Example 3, the magnetic filler uneven distribution treatment was not performed, and the magnetic filler uneven distribution degree was reduced. Diluent was blended to improve mixing.

  Using the obtained silicone elastomer, the degree of uneven distribution and sensor sensitivity were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 2

  Laboplast 100 parts by weight of millable type silicone rubber DY32-1000U (manufactured by Dow Corning Toray), 0.8 part by weight of crosslinking agent RC-4 50P FD (manufactured by Dow Corning Toray) and 100.8 parts by weight of magnetic filler The magnetic filler was uniformly dispersed by kneading with a mill (Toyo Seiki Seisakusho 4C150-01).

  After vulcanization for 10 minutes with a 170 ° C. press, secondary vulcanization was performed in an oven at 200 ° C. for 2 hours to obtain a 1 mm elastomer sheet. The obtained elastomer sheet was magnetized at 1.3 T to obtain a silicone elastomer. In this case, the magnetic filler was uniformly dispersed in the obtained silicone elastomer.

  Using the obtained silicone elastomer, the degree of uneven distribution and sensor sensitivity were measured in the same manner as in Example 1. The results are shown in Table 1.

  A silicone elastomer was obtained in the same manner as in Example 3 except that the amount of the magnetic filler was changed to 5 parts by weight.

  Using the obtained silicone elastomer, the degree of uneven distribution and sensor sensitivity were measured in the same manner as in Example 1. The results are shown in Table 1.

  A silicone elastomer was obtained in the same manner as in Example 3 except that the amount of the magnetic filler was changed to 350 parts by weight.

  Using the obtained silicone elastomer, the degree of uneven distribution and sensor sensitivity were measured in the same manner as in Example 1. The results are shown in Table 1.

  As is apparent from Table 1, when the uneven distribution degree is high as in Examples 1 to 6, the sensor sensitivity is high. On the other hand, as in Comparative Examples 1 and 2, it can be seen that when the uneven distribution is 1 or less, the sensor sensitivity is deteriorated.

  In the tactile sensor of the present invention, the magnetic filler is not uniformly dispersed in the elastomer, but is unevenly distributed. Therefore, even when the external force is small and the deformation is very small, detection with the magnetic sensor is facilitated. The magnetic filler-containing material is not separated from each other, so that it is possible to manufacture inexpensively and easily without separation between layers. Pressure distribution detection, vehicle collision state detection, body motion state detection (eg motion capture, breathing state and muscle relaxation state body motion detection, etc.), detection of illegal entry into restricted access areas, sliding door foreign object detection, It can be used for applications such as keyboard input devices.

DESCRIPTION OF SYMBOLS 1 ... Elastomer 2 ... Magnetic sensor 3 ... Magnetic filler 4 ... Board | substrate 5 ... Pressure

Claims (5)

An elastomer containing a magnetic filler;
A magnetic sensor for detecting a magnetic change caused by tactile deformation of the elastomer;
The tactile sensor is characterized in that the magnetic filler is unevenly distributed in the elastomer, and the uneven distribution degree is 1 to 100.   The tactile sensor according to claim 1, wherein the magnetic filler is unevenly distributed on one side of the elastomer, and the unevenly distributed surface is a contact surface.   3. The tactile sensor according to claim 1, wherein the magnetic filler is a rare earth-based, Fe-based, Co-based, Ni-based, or oxide-based material and has an average particle size of 0.02 to 500 μm.   The tactile sensor according to claim 1, wherein the magnetic filler is added in an amount of 1 to 450 parts by weight with respect to 100 parts by weight of the elastomer.   The tactile sensor according to claim 1, wherein the elastomer is a polyurethane elastomer or a silicone elastomer.

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