An electromagnetic induction tactile feedback system and method based on a tactile array sensor

Abstract

This invention discloses an electromagnetic induction tactile feedback system and method based on a tactile array sensor, belonging to the field of force feedback technology. It includes a tactile feedback device, a microcontroller module, a host computer, and a 3x3 tactile array sensor for a robotic arm. The tactile feedback device comprises a tactile feedback array, an elastic cloth, and an iron sheet. The tactile feedback array includes a base plate, a frame, an elastic film, a cylindrical iron core, and a coil. This invention enables a more specific and detailed sense of presence during the control of a remotely operated robot. It has a simple structure; the main force feedback component is a cylindrical iron core with a coil, requiring low processing precision and other specifications. Control is simple, utilizing electromagnetic induction to control the feedback pressure of the cylindrical iron core by controlling the current flowing into the coil. It is low-cost and has high tactile reproduction resolution, using a 3x3 tactile feedback array to reproduce the tactile sensation measured by a single tactile array sensor unit.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of force feedback, and particularly relates to an electromagnetic induction tactile feedback system and method based on a tactile array sensor. BACKGROUND

[0002] As a kind of man-machine interface device, force feedback data glove can convert force and tactile information fed back by robot into force or torque directly acting on human hand, so that operator can have 'on-the-spot' force / tactile sense effect in remote robot work site or virtual robot work site, thereby realizing control of robot with sense or generating real touch feeling in virtual environment.

[0003] When human hand is grabbing an object, the force acting on fingers is related to joint torque and pressure perpendicular to the surface of finger skin, the joint torque has the ability to prevent the movement of hand, and the pressure can be sensed by sensing cells on the skin and then transmitted to brain through neurons to form tactile sense. At present, most data gloves are driven by motor, gas or liquid, and joint torque is fed back to fingers to make people feel that the object is grabbed, thereby forming sense of presence. However, such sense of presence is not comprehensive, and only the approximate outline of the object can be felt. When two objects with same size and shape but different textures or surface concave-convex degrees are grabbed, the sense of presence formed by such data gloves will not have difference, which will lead to misjudgment of user and cause serious consequences. SUMMARY

[0004] The application aims to provide an electromagnetic induction tactile feedback system and method based on a tactile array sensor, which is used for force feedback data glove for man-machine interface of teleoperation robot control, so as to solve the problems in the background.

[0005] To achieve the above-mentioned purpose, the application provides the following technical scheme: an electromagnetic induction tactile feedback system based on a tactile array sensor, which is used for force feedback data glove for man-machine interface of teleoperation robot control, and contains a tactile feedback device, a single-chip microcomputer module, a host computer and a 3*3 tactile array sensor of mechanical hand, the tactile feedback device and the single-chip microcomputer module are electrically connected, the single-chip microcomputer module and the host computer are electrically connected, and the host computer and the 3*3 tactile array sensor of mechanical hand are electrically connected.

[0006] The tactile feedback device includes a tactile feedback array, a first elastic cloth, a second elastic cloth and an iron sheet, the left side of the tactile feedback array and the left side of the iron sheet are connected with the first elastic cloth, the right side of the tactile feedback array and the right side of the iron sheet are connected with the second elastic cloth, and the iron sheet is located directly above the tactile feedback array.

[0007] Preferably, the haptic feedback array comprises a base plate, a frame, a coil and a cylindrical core, the base plate is provided with a 9*9 rectangular array of cylindrical tubes on the top, the coil is arranged on the outside of the cylindrical tube, the cylindrical core is placed in the cylindrical tube, and the frame is bonded to the top of the base plate.

[0008] Preferably, the frame is bonded with an elastic film on the top.

[0009] Preferably, the top terminals of the coils in the same column are electrically connected and led out as a column lead, the bottom terminals of the coils in the same row are electrically connected and led out as a row lead, forming a coil array, the column lead and the row lead are electrically connected to the single-chip microcomputer module, and the coordinates of each coil unit in the coil array are represented by the serial numbers of the row lead and the column lead.

[0010] Preferably, the single-chip microcomputer module comprises a single-chip microcomputer and a current control module.

[0011] Preferably, the haptic feedback array comprises 9 3*3 haptic feedback arrays arranged in a 3*3 rectangular array, and one sensor unit in the 3*3 haptic array sensor of the robot hand corresponds to one 3*3 haptic feedback array.

[0012] A method of an electromagnetic induction haptic feedback system based on a haptic array sensor, comprising the following steps:

[0013] Step one: the user wears the haptic feedback device on the finger, and the host controls the robot hand to grab the object;

[0014] Step two: the robot hand sends the haptic information measured by the haptic array sensor to the host, the host processes the haptic information, calculates the corresponding pressure feedback by each unit of the haptic feedback array according to the coupling algorithm of the haptic feedback unit, and calculates the current required for each unit of the haptic feedback array to feedback the corresponding pressure according to the electromagnetic induction theorem;

[0015] Step three: the host sends the current information to the single-chip microcomputer, the single-chip microcomputer selects the corresponding row line and column line on the coil array for each haptic feedback array unit according to the current information to conduct the corresponding haptic feedback array unit, controls the current control module to transmit 81 times for one period, conducts one unit in the haptic feedback array each time, and transmits the current corresponding to the haptic pressure to the coil in each haptic feedback array unit;

[0016] Step four: the current on the coil magnetizes the cylindrical core, the magnetized cylindrical core generates a magnetic force on the iron sheet, and the iron sheet generates a counterforce on the cylindrical core to attract the core to move;

[0017] Step five: the cylindrical core displaces a distance and then exerts force on the finger, the finger skin exerts corresponding force on the cylindrical core, when the force is balanced, the finger will feel the touch when the robot hand grasps the object.

[0018] Preferably, the touch feedback unit coupling algorithm is:

[0019] F r (i, j) represents the pressure detected by a unit in the touch array sensor;

[0020] F l (a, b) represents the pressure feedback by a unit in the touch feedback array;

[0021] i = 1, 2, 3; j = 1, 2, 3; a = 1 ~ 9; b = 1 ~ 9

[0022] Where the coordinates are (2, 2), (2, 5), (2, 8), (5, 2), (5, 5),

[0023] (5, 8), (8, 2), (8, 5), (8, 8) are the center units, and the pressure they feedback is equal to the pressure detected by the corresponding units in the touch array sensor, as follows:

[0024] F 1 = F l (2, 2) = F r (1, 1), F 2 = F l (2, 5) = F r (1, 2), F 3 = F l (2, 8) = F r (1, 3)

[0025] F 4 = F l (5, 2) = F r (2, 1), F 5 = F l (5, 5) = F r (2, 2), F 6 = F l (5, 8) = F r (2, 3)

[0026] F 7 = F l (8, 2) = F r (3, 1), F 8 = F l (8, 5) = F r (3, 2), F 9 = F l(8,8) = F r (3,3)

[0027] The pressure value that each haptic feedback unit needs to feedback is related to the distance between the haptic feedback unit and the center unit and gradually attenuates from the center unit, so for each center unit, we calculate the pressure that other non-center units need to feedback:

[0028]

[0029] (wherein, k = 1 ~ 9, x k , y k is the coordinate of the kth center unit, a, b cannot be equal to x k , y k ) is the pressure that the non-center unit needs to feedback relative to the kth center point;

[0030] μ k is the attenuation rate, wherein

[0031]

[0032] Through the above calculation, a non-center unit will obtain nine feedback pressure values, and the maximum value is selected from the nine feedback pressure values:

[0033]

[0034] Advantages:

[0035] (1) The electromagnetic induction haptic feedback system based on the haptic array sensor of the application is used for the force feedback data glove of human-machine interface controlled by the remote operation robot, adopts the array structure, each unit in the array can exert pressure on the finger, and the force exerted by each unit is combined together to restore the haptic when the mechanical finger grips the object on the finger, so that the user can feel the specific force condition of the mechanical finger contacting the object in real time. The haptic feedback system not only enables the user to understand the force area of the mechanical finger, but also enables the user to understand the concave-convex condition of the object surface, which is beneficial to the user to make a judgment on the surface condition of the object. A kind of feedback joint force data glove cannot restore the on-the-spot feeling, and the haptic feedback system can be used in combination with the feedback joint force data glove such as CyberGrasp and Rutgers Master II, so that the on-the-spot feeling of the user is more complete and comprehensive.

[0036] (2) The present invention provides an electromagnetic induction tactile feedback system based on a tactile array sensor for a force feedback data glove for human-machine interaction in remote operation robot control. Based on the design of a tactile array sensor, each detection unit of the tactile array sensor has a corresponding 3*3 tactile feedback array. The pressure fed back by the central unit is coupled with the pressure fed back by the non-central unit through the tactile feedback unit coupling algorithm, so as to provide a more refined feeling to the force-bearing finger and make the tactile feedback resolution higher.

[0037] (3) The present invention provides an electromagnetic induction tactile feedback system based on a tactile array sensor for force feedback data gloves for human-machine interaction in remote control of robots. An elastic cloth is used to connect the tactile feedback matrix and the iron sheet, so that the tactile feedback device can be adapted to fingertips of different thicknesses. The elastic film set on the top of the frame facilitates the free movement of the iron core, prevents the iron core from leaking out of the tactile feedback array and prevents the fingers from contacting the coil. The base plate, cylindrical tube and frame are all made of resin, which helps to control the weight and makes the tactile feedback device lighter. Attached Figure Description

[0038] Figure 1 This is a block diagram of the communication structure of the present invention;

[0039] Figure 2 This is the front view of the present invention;

[0040] Figure 3 Side view of the present invention

[0041] Figure 4 This is a schematic diagram of the haptic feedback array of the present invention;

[0042] Figure 5 This is a design diagram of the coil array of the present invention.

[0043] In the diagram: 1. Tactile feedback device; 11. Tactile feedback array; 111. Base plate; 112. Frame; 113. Elastic film; 114. Coil; 115. Cylindrical iron core; 12. First elastic cloth; 13. Second elastic cloth; 14. Iron sheet; 2. Coil array. Detailed Implementation

[0044] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0045] like Figures 1-5 As shown, an electromagnetic induction tactile feedback system based on a tactile array sensor is used for force feedback data gloves for human-machine interaction in remote robot control. It includes a tactile feedback device 1, a microcontroller module, a host computer, and a 3*3 tactile array sensor for the robotic arm. The tactile feedback device 1 and the microcontroller module are electrically connected, the microcontroller module is electrically connected to the host computer, and the host computer is electrically connected to the 3*3 tactile array sensor for the robotic arm.

[0046] The haptic feedback device 1 comprises a haptic feedback array 11, a first elastic cloth 12, a second elastic cloth 13 and an iron sheet 14, the first elastic cloth 12 is connected between the haptic feedback array 11 and the left side of the iron sheet 14, the second elastic cloth 13 is connected between the haptic feedback array 11 and the right side of the iron sheet 14, and the iron sheet 14 is located directly above the haptic feedback array 11.

[0047] The haptic feedback array 11 comprises a bottom plate 111, a frame 112, a coil 114 and a cylindrical iron core 115, the top of the bottom plate 111 is provided with 81 cylindrical barrels arranged in a 9*9 rectangular array, the coil 114 is wound around the outside of the cylindrical barrel, the cylindrical iron core 115 is placed inside the cylindrical barrel, and the bottom of the frame 112 is bonded to the top of the bottom plate 111.

[0048] The top of the frame 112 is bonded with an elastic film 113, which is beneficial to the free movement of the cylindrical iron core 115, prevents the cylindrical iron core 115 from leaking out of the haptic feedback array 11, and prevents the fingers from directly contacting the coil 114, thereby protecting the fingers and further protecting the personal safety.

[0049] The top terminals of each column of coils 114 are electrically connected and led out as a column lead, the bottom terminals of each row of coils 114 are electrically connected and led out as a row lead, forming a coil array 2, and the 9 column leads led out at the top and the 9 row leads led out at the bottom are electrically connected with a single-chip microcomputer module.

[0050] The single-chip microcomputer module can comprise a single-chip microcomputer and a current control module, and the 9 column leads and the 9 row leads can be electrically connected with the single-chip microcomputer.

[0051] The number and position of the sensor units of the 3*3 haptic array sensor of the robot hand can be changed, one sensor unit of the 3*3 haptic array sensor of the robot hand corresponds to a 3*3 haptic feedback array, and the 3*3 haptic feedback array is consistent with the position of each unit of the 3*3 haptic array sensor of the robot hand.

[0052] A method of an electromagnetic induction haptic feedback system based on a haptic array sensor, comprising the following steps:

[0053] Step one: the user wears the haptic feedback device 1 on the finger, and the host controls the robot hand to grab the object;

[0054] Step two: the robot hand sends the haptic information measured by the haptic array sensor to the host, the host processes the haptic information, calculates the corresponding pressure feedback of each unit of the haptic feedback array 11 according to the haptic feedback unit coupling algorithm, and calculates the current required for each unit of the haptic feedback array 11 to feedback the corresponding pressure according to the electromagnetic induction theorem;

[0055] Step three: the host sends current information to the single-chip microcomputer, which selects the corresponding row and column conductors on the coil array 2 of each tactile feedback array 11 unit according to the current information to turn on the corresponding tactile feedback array 11 unit, controls the current control module to transmit 81 times for one cycle, and turns on one unit in the tactile feedback array 11 each time to transmit a current corresponding to the tactile size to the coil 114 in each tactile feedback array 11 unit;

[0056] Step four: the current on the coil 114 magnetizes the cylindrical iron core 115, the magnetized cylindrical iron core 115 generates a magnetic force on the iron sheet 14, and the iron sheet 14 generates a counterforce on the cylindrical iron core 115 to attract the cylindrical iron core to move;

[0057] Step five: the cylindrical iron core 115 generates a force on the finger after a certain displacement, and the finger skin generates a corresponding force in response to the cylindrical iron core 115, and when the force balance is reached, the finger will feel the tactile sensation when the robot hand grasps the object.

[0058] A tactile feedback unit coupling algorithm:

[0059] F r (i, j) represents the pressure detected by a unit in the tactile array sensor;

[0060] F l (a, b) represents the pressure feedback by a unit in the tactile feedback array;

[0061] Take a 3*3 tactile array sensor and a tactile feedback array 11 as an example,

[0062] i = 1, 2, 3; j = 1, 2, 3; a = 1~9; b = 1~9

[0063] Where the coordinates (2, 2), (2, 5), (2, 8), (5, 2), (5, 5), (5, 8), (8, 2), (8, 5), and (8, 8) are the center units, and the pressure they feedback is equal to the pressure detected by the corresponding units in the tactile array sensor, as follows:

[0064] F 1 = F l (2, 2) = F r (1, 1), F 2 = F l (2, 5) = F r (1, 2), F 3 = F l (2, 8) = F r (1, 3)

[0065] F 4 = Fl (5, 2) = F r (2, 1), F 5 =F l (5, 5) = F r (2,2),F 6 =F l (5, 8) = F r (2, 3)

[0066] F 7 =F l (8, 2) = F r (3, 1), F 8 =F l (8, 5) = F r (3, 2), F 9 =F l (8, 8) = F r (3,3)

[0067] We assume that the pressure value required by each haptic feedback unit is related to the distance between that haptic feedback unit and the central unit, and gradually decreases starting from the central unit. Therefore, for each central unit, we calculate the pressure required by all other non-central units:

[0068]

[0069] (where k = 1 to 9, x k Let y and x be the coordinates of the k-th central unit, and a and b cannot both be equal to x. k y k ) The pressure that needs to be fed back to the non-central unit relative to the k-th center point;

[0070] μ k Let be the decay rate, where

[0071]

[0072] Based on the above calculations, a non-central unit will obtain nine pressure values, from which the maximum value is selected:

[0073]

[0074] The electromagnetic induction tactile feedback system based on the tactile array sensor is used for the force feedback data glove for the human-machine interface of the remote control robot, adopts the array structure, each unit in the array can exert pressure on the finger, the force exerted by each unit is combined together to restore the tactile feeling when the mechanical finger grips the object on the finger, so that the user can feel the specific force condition of the mechanical finger contacting the object in real time, the tactile feedback system can not only make the user know the force area of the mechanical finger, but also know the concave-convex condition of the object surface, is beneficial to the user to make the judgment on the surface condition of the object, can restore the on-the-spot feeling which cannot be restored by the data glove with feedback joint force, and when the data glove with feedback joint force such as CyberGrasp and Rutgers Master II is used, the on-the-spot feeling of the user is more complete and comprehensive.

[0075] The electromagnetic induction tactile feedback system based on the tactile array sensor is used for the force feedback data glove for the human-machine interface of the remote control robot, is designed based on the tactile array sensor, each detection unit of the tactile array sensor has a 3*3 tactile feedback array corresponding, the pressure feedback of the center unit and the pressure feedback of the non-center unit are coupled through the coupling algorithm of the tactile feedback unit, so that the force finger is fed back to a more delicate feeling, and the tactile feedback resolution is higher.

[0076] The electromagnetic induction tactile feedback system based on the tactile array sensor is used for the force feedback data glove for the human-machine interface of the remote control robot, the elastic cloth is used between the tactile feedback matrix and the iron sheet, so that the tactile feedback device can be suitable for the fingertips of different thickness; the elastic film arranged at the top of the frame is beneficial to the free movement of the iron core, prevents the iron core from leaking out of the tactile feedback array and prevents the finger from contacting the coil; the bottom plate, the cylindrical barrel and the frame are all made of resin, which is beneficial to controlling the weight and making the tactile feedback device lighter.

[0077] The specific embodiments of the present application are described in detail above, but it is only as an example, the present application is not limited to the above described specific embodiments. For those skilled in the art, any equivalent modification and replacement of the present application are also within the scope of the present application. Therefore, the equivalent transformation and modification made without departing from the spirit and scope of the present application are all covered in the scope of the present application.

Claims

1. An electromagnetic induction tactile feedback method based on tactile array sensor, an electromagnetic induction tactile feedback system thereof is used for the force feedback data glove of human-machine interface controlled by teleoperation robot, comprising a tactile feedback device (1), a single-chip microcomputer module, a host computer and a 3*3 tactile array sensor of a manipulator, the tactile feedback device (1) and the single-chip microcomputer module are electrically connected, the single-chip microcomputer module and the host computer are electrically connected, and the host computer and the 3*3 tactile array sensor of the manipulator are electrically connected. The tactile feedback device (1) comprises a tactile feedback array (11), a first elastic cloth (12), a second elastic cloth (13) and an iron sheet (14), the left side of the tactile feedback array (11) and the left side of the iron sheet (14) are connected with the first elastic cloth (12), the right side of the tactile feedback array (11) and the right side of the iron sheet (14) are connected with the second elastic cloth (13), and the iron sheet (14) is located directly above the tactile feedback array (11). characterized in that : The method comprises the following steps: Step one: the user wears the tactile feedback device (1) on the finger, and the host computer controls the manipulator to grab the object; Step two: the manipulator sends the tactile information measured by the 3*3 tactile array sensor of the manipulator to the host computer, the host computer processes the tactile information, calculates the corresponding pressure feedback by each unit of the tactile feedback array (11) according to the tactile feedback unit coupling algorithm, and calculates the current required for each unit of the tactile feedback array (11) to feedback the corresponding pressure according to the electromagnetic induction theorem; Step three: the host computer sends the current information to the single-chip microcomputer, the single-chip microcomputer selects the corresponding row lead and column lead of each tactile feedback array (11) unit on the coil array (2) to turn on the corresponding tactile feedback array (11) unit according to the current information, controls the current control module to transmit 81 times as a cycle, turns on one unit in the tactile feedback array (11) each time, and transmits the current corresponding to the tactile pressure to the coil (114) in each tactile feedback array (11) unit; Step four: the current on the coil (114) magnetizes the cylindrical iron core (115), the magnetized cylindrical iron core (115) generates a magnetic force on the iron sheet (14), the iron sheet (14) generates a counterforce on the cylindrical iron core (115) to attract the iron core to move; Step five: the cylindrical iron core (115) generates a force on the finger after moving a distance, the finger skin generates a corresponding counterforce on the cylindrical iron core (115), and when the force balance is reached, the finger will feel the tactile feeling when the manipulator grabs the object.

2. The electromagnetic induction tactile feedback method based on the tactile array sensor according to claim 1, characterized in that: The haptic feedback array (11) comprises a bottom plate (111), a frame (112), a coil (114) and a cylindrical core (115), the top of the bottom plate (111) is provided with a cylindrical barrel arranged in a 9*9 rectangular array, the coil (114) is arranged on the outer side of the cylindrical barrel, the cylindrical core (115) is placed in the cylindrical barrel, and the bottom of the frame (112) is bonded to the top of the bottom plate (111).

3. The electromagnetic induction haptic feedback method based on a haptic array sensor according to claim 2, characterized in that: The top of the frame (112) is bonded with an elastic film (113).

4. The electromagnetic induction haptic feedback method based on the haptic array sensor according to claim 2, characterized in that: The top terminals of the coils (114) in the same column are electrically connected and led out as a column lead, the bottom terminals of the coils (114) in the same row are electrically connected and led out as a row lead, forming a coil array (2), the column lead and the row lead are electrically connected with a single-chip microcomputer module, and the coordinates of each coil unit in the coil array (2) are represented by the serial numbers of the row lead and the column lead.

5. The electromagnetic induction haptic feedback method based on the haptic array sensor according to claim 1, characterized in that: The single-chip microcomputer module comprises a single-chip microcomputer and a current control module.

6. The electromagnetic induction haptic feedback method based on the haptic array sensor according to claim 5, characterized in that: The haptic feedback array (11) comprises nine 3*3 haptic feedback arrays arranged in a 3*3 rectangular array, and one sensor unit in the 3*3 haptic array sensor of the mechanical hand corresponds to one 3*3 haptic feedback array.

7. The electromagnetic induction haptic feedback method based on a haptic array sensor according to claim 1, wherein, The haptic feedback unit coupling algorithm: Pij represents the pressure detected by one cell of the tactile array sensor; , represents the pressure of a unit feedback in the tactile feedback array; where the coordinates are The haptic feedback units are the center units, and the pressure they feedback is equal to the pressure detected by the corresponding units in the haptic array sensor, as follows: The pressure value required by each haptic feedback unit for feedback is related to the distance between the haptic feedback unit and the center unit and gradually decays from the center unit, so for each center unit, the pressure to be fed back by other non-center units is calculated: wherein k = 1 ~ 9, x k , y k is the coordinate of the kth central unit, a, b cannot be equal to x k , y k at the same time; Pk is the pressure needed for the feedback for the kth center point non-center cell; for the decay rate, where Through the above calculation, a non-center unit will obtain nine feedback pressure values, and then the maximum value is selected from the nine feedback pressure values: 。

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