CN103335754A - Fully-flexible three-dimensional force tactile sensor - Google Patents

Abstract

The invention discloses a fully-flexible three-dimensional force tactile sensor. The fully-flexible three-dimensional force tactile sensor is characterized in that in a flexible basal body and on the same plane, a resistor R5 is formed by taking a pressure sensitive element as a center, and four same stretching sensitive elements are respectively arranged in the Y-axis positive direction, the Y-axis negative direction, the X-axis positive direction and the X-axis negative direction respectively, so as to form a resistor R1, a resistor R3, a resistor R2 and a resistor R4; the resistor R1, the resistor R2, the resistor R3, the resistor R4 and the resistor R5 form a three-dimensional force tactile sensing unit which is arranged on the surface of an area to-be-detected. All three-dimensional force tactile sensing units are in an array arrangement on the surface of the area to-be-detected; flexible basal bodies are filled among the three-dimensional force tactile sensing units; the three-dimensional force tactile sensing units and the flexible basal bodies form the three-dimensional force tactile sensor. The three-dimensional force tactile sensor has the advantages of good flexibility, high precision and stable performance.

Description

Full flexible 3 D force-touch sensor

Technical field

The invention belongs to field of sensing technologies, relate in particular to a kind of 3 D force-touch sensor that is applied to robot.

Background technology

Along with the development of Robotics, the research of touch sensor has received increasing concern.At present comparatively ripe to the research of one-dimensional power sensor, but as the intelligent skin of robot, not only need sensor can realize that detection to surperficial pressure at right angle, while also need the shearing force that sensor can the detection level direction.When gripping object as robot, need the perception tangential force, the positive pressure of perception simultaneously.When robot contacts the object of some surface imperfections, need to realize the detection of three-dimensional even multi-dimensional direction power.The development of 3 D force-touch sensor has become intelligent robot technology's a important research field.

Develop multiple three-dimensional force sensor at present both at home and abroad, be used for robot skin.The mode that the people such as Van A H of Japan utilize the MEMS technology to paste pressure-sensitive film resistance in the rood beam structure has been made the 3 D force-touch sensor that is used for the robot finger; The people such as Huang of Taiwan National Chenggong University utilize crooked platinum/titanium film, one section is fixed and be arranged to the rood beam structure, have made the touch sensor for detection of vertical force and shearing force; The people such as Su of Taiwan National Tsing Hua University generate anisotropic carbon nano-tube at silicon substrate, but and with its transfer and revolve the flexible touch sensation sensor that figure has made detection of vertical power and shearing force to the PDMS; These sensors that are used for measurement three-dimensional force information mainly adopt metal or metal oxide rood beam or semiconductor material etc., and these materials all are rigid materials, do not have flexibility.

People such as Chen are matrix material with PDMS and PET, but ITO has made the flexible capacitance type touch sensor of detection of vertical and shearing force as electrode; The people such as Xu Fei of Hefei intelligent machine research institute of Chinese University of Science and Technology are matrix material with carbon black/silicon rubber, and are routed to criss-cross construction in the material internal levels, have made the three-dimensional force flexible touch sensation sensor, have realized the detection to three-dimensional force.Though this three-dimensional force sensor that utilizes conductive rubber to make has certain flexibility, its electrode and the two-sided form characteristics that contact of force-sensitive material cause the sensor production process that very big difficulty is arranged, and also unreliable in stability and sensitivity.

Summary of the invention

The present invention is that a kind of flexibility is good, precision is high, the full flexible 3 D force sensor array of stable performance for the artificial sensitive skin of intelligent robot provides.

The present invention adopts following technical scheme for the technical solution problem:

The design feature of the full flexible 3 D force-touch sensor of the present invention is: in flexible substrate, in the same plane, form resistance R 5 centered by a presser sensor spare; Be arranged in Y-axis positive dirction, Y-axis negative direction, X-axis positive dirction and X-axis positive dirction respectively with four identical stretching position-sensing units, form resistance R respectively ₁, resistance R ₃, resistance R ₂And resistance R ₄, constitute the three-dimensional force tactile sensing unit that is arranged on detected area surfaces; Each three-dimensional force tactile sensing unit is arranged in array in detected area surfaces, and flexible substrate is filled each other, constitutes 3 D force-touch sensor.

The design feature of the full flexible 3 D force-touch sensor of the present invention also is:

Described stretching position-sensing unit is that the compliant conductive rubber that forms with filling carbon nano-pipe in silicon rubber is material; Described presser sensor spare is that the compliant conductive rubber with carbon black-filled formation in silicon rubber is material; Described flexible substrate is to fill silicon dioxide in silicon rubber, makes that described flexible substrate is consistent with the hardness of pulling force position-sensing unit and presser sensor spare.

Three-dimensional force in the described three-dimensional force tactile sensing unit is pressed following formula and is resolved acquisition:

$k_x{F}_x=\frac{{\mathrm{\&Delta;<figure-callout\; id="2"\; label="R"\; filenames="HDA00003366540200011.png,HDA00003366540200021.png"\; state="\{\{state\}\}">R</figure-callout>}}_2/R_2-{\mathrm{\&Delta;R}}_4/R_4}{2}$

$k_y{F}_y=\frac{{\mathrm{\&Delta;<figure-callout\; id="1"\; label="R"\; filenames="HDA00003366540200011.png,HDA00003366540200021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1/R_1-{\mathrm{\&Delta;<figure-callout\; id="3"\; label="R"\; filenames="HDA00003366540200011.png,HDA00003366540200021.png"\; state="\{\{state\}\}">R</figure-callout>}}_3/R_3}{2}$

k _zF _z＝ΔR ₅/R ₅

In the following formula:

F _x, F _yAnd F _zIt is respectively three-dimensional force tactile sensing unit suffered acting force on x, y and z direction;

k _x, k _yAnd k _zBe respectively that three-dimensional force tactile sensing unit is for directed force F _x, F _yAnd F _zResistance coefficient, described k _x, k _yAnd k _zDemarcate acquisition by test;

R ₁, R ₂, R ₃, R ₄And R ₅The initial resistance of resistance that is respectively three-dimensional force tactile sensing unit on the y axle positive dirction under the stress not, the initial resistance of resistance on the x axle positive dirction, the initial resistance of resistance on the y axle negative direction, the initial resistance of resistance on the x axle negative direction, and the resistance initial value on the z direction of principal axis;

Δ R ₁, Δ R ₂, Δ R ₃, Δ R ₄With Δ R ₅Be when being subjected to acting force in three-dimensional force tactile sensing unit, to be arranged in the resistance change amount that respectively stretches position-sensing unit and be positioned at the presser sensor spare at center on Y-axis positive dirction, X-axis positive dirction, Y-axis negative direction and the X-axis positive dirction respectively.

Compared with the prior art, beneficial effect of the present invention is embodied in:

1, all of the full flexible 3 D force sensor array of the present invention are made materials and are comprised stretching sensitive material, pressure sensitive material, and matrix material is flexible material, satisfy artificial skin to the requirement of flexibility;

2, the present invention adopts cross structure, and with Fx, Fy and Fz decompose out, have reduced the degree of coupling of resistance data, also reduces the decoupling zero difficulty of algorithm, makes real-time detection become possibility;

3, the used three-dimensional force of the present invention unit adopts the method for global formation to finalize the design, its compact conformation, and globality is strong, thereby makes its working stability, and is easy to use, and adaptability is good, and is applied widely;

What 4, the range of three-dimensional force of the present invention and sensitivity can be by contained Packed component ratio and scantlings in stretching sensitive material and the pressure sensitive material is controlled, and range of adjustment is wide.

Description of drawings

Fig. 1 is three-dimensional force sensing unit structural representation of the present invention;

Fig. 2 is five equivalent resistance position distribution of three-dimensional force sensor of the present invention synoptic diagram;

Fig. 3 is the array example structural representation figure of invention sensor;

Number in the figure: 1 stretching sensitive material; 2 pressure sensitive materials; 3 flexible substrates.

Embodiment

Referring to Fig. 1, Fig. 2 and Fig. 3, the version of full flexible 3 D force-touch sensor is in the present embodiment: in flexible substrate, in the same plane, form resistance R 5 centered by a presser sensor spare; Be arranged in Y-axis positive dirction, Y-axis negative direction, X-axis positive dirction and X-axis positive dirction respectively with four identical stretching position-sensing units, form resistance R respectively ₁, resistance R ₃, resistance R ₂And resistance R ₄, constitute the three-dimensional force tactile sensing unit that is arranged on detected area surfaces; Each three-dimensional force tactile sensing unit is arranged in array in detected area surfaces, and flexible substrate is filled each other, constitutes 3 D force-touch sensor.

The version of full flexible 3 D force-touch sensor also is in the present embodiment: the stretching position-sensing unit is that the compliant conductive rubber that forms with filling carbon nano-pipe in silicon rubber is material; Described presser sensor spare is that the compliant conductive rubber with carbon black-filled formation in silicon rubber is material; Described flexible substrate is to fill silicon dioxide in silicon rubber, makes that described flexible substrate is consistent with the hardness of pulling force position-sensing unit and presser sensor spare.

In concrete the enforcement, be arranged in presser sensor spare be that to utilize the compliant conductive rubber of the carbon black-filled formation of silicon rubber be that material prepares in advance, about the correlation technique content of this material " functional material " second phase in 2010 at the domestic unified edition number of International Standard Serial Number: ISSN1001-9731: CN50-1099/TH, the document 1 existing open report of the conducing composite material of combined type flexible touch sensation sensor " be used for research " of being delivered by people such as Zhao Xing, Huang Ying has been put down in writing its good pressure resistance characteristic and has been verified in the document 1.Four identical stretching position-sensing units are that the compliant conductive rubber that forms with filling carbon nano-pipe in silicon rubber is that material prepares in advance, about the correlation technique content of this material " functional material " the 6th phase in 2013 at the domestic unified edition number of International Standard Serial Number: ISSN1001-9731: CN50-1099/TH, by Miu Wei, Huang Ying, existing open report has been put down in writing its good stretching resistance characteristic and has been verified in the document 2 of " based on the principle Analysis of the carbon black/silicon rubber stretch sensor of GEM model " that people such as Li Ruiqi deliver in the document 2.

Concrete preparation is to encapsulate as a whole with flexible substrate between presser sensor spare and the stretching position-sensing unit and on every side, the flexible substrate material that adopts is to fill the flexible insulator that silicon dioxide forms in silicon rubber, can control the hardness of flexible substrate by the content of adjusting silicon dioxide in the flexible insulator, make that the hardness of flexible substrate is consistent with the hardness of pulling force position-sensing unit and presser sensor spare.

When Z direction masterpiece was used on the sensing unit, sensor unit was subjected to force compresses, and its resistance of presser sensor spare pressurized is according to the size generation respective change of pressure at this moment.As X, when the Y-direction masterpiece is used on the sensor surface, sensor unit is stretched by shearing force, and the stretching position-sensing unit is subjected to its resistance of pulling force according to the size of pulling force corresponding the variation to be taken place.

In Fig. 2, the resistance of four stretching position-sensing units and a presser sensor spare forms five equivalent resistances, realizes that three-dimensional force detects.

The mechanism that three-dimensional force information is detected is: three-dimensional force is passed through the flexible substrate material effects in the quick material of pressure and stretching sensitive material, the equivalent resistance R of stretching sensitive material ₁, R ₂, R ₃And R ₄Resistance will change when being subjected to strain.Can realize F by the measurement to four resistance variations _x, F _yDetection, the equivalent resistance R of pressure sensitive material ₅Resistance changes when being subjected to strain, by to resistance R ₅The measurement that changes can realize F _zDetection.

According to existing research, the size of pressure sensitive material and stretching sensitive material all to strain export big or small influential.

Work as F _xDo the time spent, R ₁Be subjected to compressive strain resistance and reduce R ₃Stretching strain resistance increases, and R ₂With R ₄Be subjected to stretching strain but the strain facies that is subjected to can be offset by calculating mutually, resistance variations is ignored.

Work as F _yDo the time spent, R ₂Be subjected to compressive strain resistance and reduce R ₄The increase of stretching strain resistance is subjected to stretching strain but the strain facies that is subjected to can be by calculating counteracting mutually, and resistance variations is ignored.

Work as F _zDo the time spent, R ₅Be subjected to compressive strain, resistance reduces.

The sensor output voltage signal is input to computing machine through switching gate circuit, voltage contrasting amplified circuit, data acquisition conversion, handles through matrix operation, obtains F _x, F _y, F _zValue.

Three-dimensional force in the three-dimensional force tactile sensing unit is pressed following formula and is resolved acquisition:

$k_x{F}_x=\frac{{\mathrm{\&Delta;<figure-callout\; id="2"\; label="R"\; filenames="HDA00003366540200011.png,HDA00003366540200021.png"\; state="\{\{state\}\}">R</figure-callout>}}_2/R_2-{\mathrm{\&Delta;R}}_4/R_4}{2}$

$k_y{F}_y=\frac{{\mathrm{\&Delta;<figure-callout\; id="1"\; label="R"\; filenames="HDA00003366540200011.png,HDA00003366540200021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1/R_1-{\mathrm{\&Delta;<figure-callout\; id="3"\; label="R"\; filenames="HDA00003366540200011.png,HDA00003366540200021.png"\; state="\{\{state\}\}">R</figure-callout>}}_3/R_3}{2}$

k _zF _z＝ΔR ₅/R ₅

In the following formula:

F _x, F _yAnd F _zIt is respectively three-dimensional force tactile sensing unit suffered acting force on x, y and z direction;

k _x, k _yAnd k _zBe respectively that three-dimensional force tactile sensing unit is for directed force F _x, F _yAnd F _zResistance coefficient, described k _x, k _yAnd k _zDemarcate acquisition by test;

R ₁, R ₂, R ₃, R ₄And R ₅The initial resistance of resistance that is respectively three-dimensional force tactile sensing unit on the y axle positive dirction under the stress not, the initial resistance of resistance on the x axle positive dirction, the initial resistance of resistance on the y axle negative direction, the initial resistance of resistance on the x axle negative direction, and the resistance initial value on the z direction of principal axis;

Δ R ₁, Δ R ₂, Δ R ₃, Δ R ₄With Δ R ₅Be when being subjected to acting force in three-dimensional force tactile sensing unit, to be arranged in the resistance change amount that respectively stretches position-sensing unit and be positioned at the presser sensor spare at center on Y-axis positive dirction, X-axis positive dirction, Y-axis negative direction and the X-axis positive dirction respectively.

The touch sensor that the present invention is based on compliant conductive rubber can be made by following technology:

At first, adopt the room temperature synthesis technique to make presser sensor spare and stretching position-sensing unit according to the method for putting down in writing in document 1 and the document 2; With pressure sensitive material and the impact briquetting of stretching sensitive material, and according to Fig. 1 construction packages in insulation flexible substrate material, flexible insulation matrix adopting silicon rubber mixes formation with silicon dioxide, make that the hardness of flexible insulation matrix and pressure sensitive material are suitable with the stretching sensitive material.

Afterwards, touch sensor based on flexible pressure-sensitive conductive rubber is demarcated, act on sensor repeatedly and detect resistance value and the relation of exerting pressure at the situation lower sensor of different pressures respectively with the pressure of different sizes, with this sensor is demarcated, by extract and handle three voltage signals that each three-dimensional force sensing unit is exported in the three-dimensional force sensitization array under three-dimensional contact force effect, obtain linear coupled relation between stressed and three voltage signals of all directions through linear decoupling zero, obtain coupled relation between each sensing unit through neural network decoupling again.

Claims (3)

1. full flexible 3 D force-touch sensor is characterized in that: in flexible substrate, in the same plane, form resistance R 5 centered by a presser sensor spare; Be arranged in Y-axis positive dirction, Y-axis negative direction, X-axis positive dirction and X-axis positive dirction respectively with four identical stretching position-sensing units, form resistance R respectively ₁, resistance R ₃, resistance R ₂And resistance R ₄, constitute the three-dimensional force tactile sensing unit that is arranged on detected area surfaces; Each three-dimensional force tactile sensing unit is arranged in array in detected area surfaces, and flexible substrate is filled each other, constitutes 3 D force-touch sensor.

2. full flexible 3 D force-touch sensor according to claim 1 is characterized in that: described stretching position-sensing unit is that the compliant conductive rubber that forms with filling carbon nano-pipe in silicon rubber is material; Described presser sensor spare is that the compliant conductive rubber with carbon black-filled formation in silicon rubber is material; Described flexible substrate is to fill silicon dioxide in silicon rubber, makes that described flexible substrate is consistent with the hardness of pulling force position-sensing unit and presser sensor spare.

3. full flexible 3 D force-touch sensor according to claim 1 is characterized in that: the three-dimensional force in the described three-dimensional force tactile sensing unit is pressed following formula and is resolved and obtain:

$k_x{F}_x=\frac{{\mathrm{\&Delta;R}}_2/R_2-{\mathrm{\&Delta;R}}_4/R_4}{2}$

$k_y{F}_y=\frac{{\mathrm{\&Delta;R}}_1/R_1-{\mathrm{\&Delta;R}}_3/R_3}{2}$

k _zF _z＝ΔR ₅/R ₅

In the following formula:

F _x, F _yAnd F _zIt is respectively three-dimensional force tactile sensing unit suffered acting force on x, y and z direction;

k _x, k _yAnd k _zBe respectively that three-dimensional force tactile sensing unit is for directed force F _x, F _yAnd F _zResistance coefficient, described k _x, k _yAnd k _zDemarcate acquisition by test;

R ₁, R ₂, R ₃, R ₄And R ₅The initial resistance of resistance that is respectively three-dimensional force tactile sensing unit on the y axle positive dirction under the stress not, the initial resistance of resistance on the x axle positive dirction, the initial resistance of resistance on the y axle negative direction, the initial resistance of resistance on the x axle negative direction, and the resistance initial value on the z direction of principal axis;

Δ R ₁, Δ R ₂, Δ R ₃, Δ R ₄With Δ R ₅Be when being subjected to acting force in three-dimensional force tactile sensing unit, to be arranged in the resistance change amount that respectively stretches position-sensing unit and be positioned at the presser sensor spare at center on Y-axis positive dirction, X-axis positive dirction, Y-axis negative direction and the X-axis positive dirction respectively.

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