WO2023236422A1 - Two-finger gripping force and tactile feedback device - Google Patents

Abstract

A two-finger gripping force and tactile feedback device, comprising: a bearing seat (10); a driving mechanism, the driving mechanism being provided in the bearing seat (10); and a connecting rod structure which comprises two connecting rod mechanisms (20), wherein each connecting rod mechanism comprises a front-end connecting rod (201) and a rear-end connecting rod (202) which are movably connected, the driving mechanism can adjust the angle between the two front-end connecting rods (201), and the rear-end connecting rods (202) can rotate relative to the front-end connecting rods (201). The present invention has a simple structure, and by providing the connecting rod structure at the index finger and the middle finger, resistance to the fingers gripping an object is provided, so that real kinesthetic feedback of two fingers gripping an object is achieved; an air bag piece (50) is connected to flexible pads (30) and is arranged at the bottom of the gap between the fingers, the gripping action of the index finger and the middle finger is limited by means of pressing between air bags and by means of the connecting rod structure, and force feedback information is transmitted, thereby further improving the accuracy of kinesthetic feedback of finger gripping; piezoelectric ceramic (60) is provided on the flexible pads (30), and the inverse piezoelectric effect of the piezoelectric ceramic (60) can be used for high-frequency contact surface driving so as to transmit tactile information of the inner sides of two fingers of the performer.

Description

Two-finger gripping force tactile feedback device Technical field

The invention relates to the technical field of human-computer interaction, and in particular to a two-finger clamping force tactile feedback device.

Background technique

In the process of human contact with the natural objective world, the human tactile sensory feedback system provides two-way information and energy interaction that other sensory systems (visual or auditory, etc.) do not have.

The force tactile feedback device is a system that can bring tactile and force information to the experiencer and transmit bidirectional information feedback. It can greatly increase the sense of reality and immersion that the virtual world brings to the experiencer. Nowadays, immersive virtual development focuses on feedback. The initial development started with wearable devices (gloves, etc.). Feedback gloves are based on data gesture gloves, with tactile feedback units added to fingertips and palms. When wearing a data glove with force feedback to grasp a virtual object, the data glove should be able to generate a force that causes the human hand to move outward. The size and direction of this force must be the same as the force generated on the human hand when the real object exists. Thus achieving an immersive experience.

technical problem

Existing force tactile feedback actuators focus on the tactile feedback information transmitted by the operator's fingers grasping and touching objects, but ignore the relationship between the other four fingers (index finger, middle finger, ring finger, and little finger) of human fingers except the thumb. Based on the force tactile information feedback, when the human fingers grasp an object, due to the natural inertia of the fingers, the four fingers except the thumb will consciously move closer and contract. When performing virtual operations on precision machinery, the position of each finger is crucial, and the posture distance between the fingers is required to be accurate. When using fingers other than the thumb to hold an object in virtual operations, a feedback actuator is required to feed back the force tactile information of the held object in the virtual world to the executor, and the executor will perform the next operation based on the transmitted information.

Technical solutions

In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a two-finger clamping force tactile feedback device.

In order to achieve the above object, the technical solution provided by an embodiment of the present invention is as follows:

A two-finger holding force tactile feedback device, including:

Bearing seat;

Driving mechanism, the driving mechanism is located in the bearing seat;

The link structure includes two link mechanisms, each of the link mechanisms includes a movably connected front end link and a rear end link, and the drive mechanism can adjust the angle between the two front end links, so The rear end link can rotate relative to the front end link.

beneficial effects

(1) The present invention has a simple structure. By arranging a connecting rod structure at the index finger and middle finger, it provides resistance for the fingers to hold objects, thereby achieving real kinesthetic feedback of holding objects between two fingers.

(2) By arranging the airbag piece connected to the flexible pad and setting it at the bottom of the finger gap, the extrusion between the airbags is used, and the connecting rod structure is used to limit the clamping action of the index finger and the middle finger, transmit force feedback information, and further improve the finger grip. Accuracy of kinesthetic feedback.

(3) Piezoelectric ceramics are placed on the flexible pad, and its inverse piezoelectric effect can be used for high-frequency contact surface driving to transmit tactile information on the inside of the operator's two fingers.

Description of the drawings

In order to more clearly explain the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to describe the embodiments or the prior art will be briefly introduced below.

Figure 1 is a schematic structural diagram of the index finger and middle finger division module for virtual fingers in Unity3D according to the preferred embodiment of the present invention;

Figure 2 is an overall view of a preferred embodiment of the present invention;

Figure 3 is a schematic structural diagram of the preferred embodiment of the present invention worn on the index finger and middle finger;

Figure 4 is a schematic structural diagram of the preferred embodiment of the present invention driving the index finger and middle finger to bend;

Figure 5 is a schematic structural diagram of the front-end connecting rod according to the preferred embodiment of the present invention;

Figure 6 is a schematic structural diagram of the rear-end connecting rod according to the preferred embodiment of the present invention;

Figure 7 is a schematic structural diagram of the connection between the front-end connecting rod and the rear-end connecting rod according to the preferred embodiment of the present invention;

Figure 8 is a schematic structural diagram of the rear-end link rotating relative to the front-end link according to the preferred embodiment of the present invention;

Figure 9 is a schematic structural diagram of a flexible pad according to a preferred embodiment of the present invention;

Figure 10 is a schematic structural diagram of the airbag sheet according to the preferred embodiment of the present invention;

Figure 11 is a perspective view of the driving assembly according to the preferred embodiment of the present invention;

Figure 12 is a front view of the driving assembly of the preferred embodiment of the present invention;

In the figure: 1. Index finger proximal phalanx module, 2. Index finger middle phalanx module, 3. Middle finger proximal phalanx module, 4. Middle finger middle phalanx module, 10. Bearing seat, 101. Driving assembly, 102. Motor, 103 , strut, 104, first gear, 105, second gear, 106, bearing, 107, wire, 20, link mechanism, 201, front-end connecting rod, 202, rear-end connecting rod, 203, gap, 204, pin Shaft, 30, flexible pad, 401, front end ferrule, 402, rear end ferrule, 403, first transition rod, 404, second transition rod, 50, air bag sheet, 501, air bag body, 502, air bag, 60, Piezoelectric ceramics, 71. Proximal phalanx of index finger, 72. Middle phalanx of index finger, 73. Proximal phalanx of middle finger, 74. Middle phalanx of middle finger.

Embodiments of the invention

In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will be combined with the accompanying drawings in the embodiments of the present invention.

Unity3D software is used to create virtual scenes and objects in the scene, and inertial sensors are used to create virtual models. Inertial sensors include three types of sensors: accelerometer, gyroscope, and magnetometer. The sensors are used to obtain the posture data of the hand and finger bending, and then the hand is After the data is processed, it is imported into the Unity scene to obtain the hand model, and then the USB wireless signal receiver is connected to the specific hand model data interface to obtain the hand data and real-time changes in posture and send the data through broadcast. The corresponding broadcast data is connected to the UI interface of Unity's hand operation to obtain the hand posture in Unity in real time.

Import the steamVR software development kit, combine the two software development kits, and install HTC VIVE's Tracker is placed on the wrist, and the locator steamVR2.0 is installed in the real scene. Through the combination of the software development kit, the position of the tracker within the scope of the locator and the position of the virtual hand in the Unity scene in the Main Camera's field of view Matching is performed to achieve real-time consistency between the movement and posture of the human hand in the real scene and the position and posture of the virtual model hand in Unity. For the virtual hand division module in Unity3D, divide the inner parts of the index finger and middle finger into fine modules, namely index finger proximal phalanx module 1, index finger middle phalanx module 2, middle finger proximal phalanx module 3, and middle finger middle phalanx module 4, such as As shown in Figure 1, a collision detection algorithm is added to each module to allow the virtual model to touch or grasp different objects, which can accurately trigger the collision detection algorithm of the corresponding module that touches the object, and deliver accurate collisions through the PC. signal, perform data conversion and next step operation on the signal.

Please refer to Figures 2 to 4. A two-finger clamping force tactile feedback device includes: a bearing base 10; a driving mechanism, which is located in the bearing base 10; a link structure, including two link mechanisms 20, each The link mechanism 20 includes a movably connected front-end link 201 and a rear-end link 202. The driving mechanism can adjust the angle between the two front-end links 201, and the rear-end link 202 can rotate relative to the front-end link 201. The front end and back end are based on the extension direction of the fingers. The one close to the palm is the front end, and the one far away from the palm is the back end.

In order to improve the comfort of wearing the fingers and facilitate the free bending of the fingers, it is preferred that each link mechanism 20 is connected to a limiter, and a flexible pad 30 is provided on the limiter, and the flexible pad 30 is close to the inside of the finger.

Specifically, the limiting member includes a front-end ferrule 401 and a rear-end ferrule 402. The front-end ferrule 401 and the rear-end ferrule 402 are respectively connected to the front-end connecting rod 201 and the rear-end connecting rod 202. The flexible pad 30 is arranged on the front-end ferrule. On the sleeve 401 and the back-end ferrule 402, through the arrangement of the front-end ferrule 402 and the rear-end ferrule 402, it is possible to facilitate the feedback device to be stably worn on the finger and improve the accuracy of force transmission. Specifically, multiple flexible pads 30 are provided and can be respectively connected to the front end of the front end ferrule 401, between the front end ferrule 401 and the rear end ferrule 402, and to the rear end of the rear end ferrule 402.

In this embodiment, an air bag piece 50 is connected between the two front-end ferrules 401 to facilitate inflating the air bag piece 50. When two adjacent fingers come close to each other, the air bag piece 50 will be squeezed, and at the same time, the air bag piece 50 will inflate the air bag piece 50. and finger resistance, thereby transmitting force feedback information to the finger. As shown in Figure 10, the airbag sheet 50 includes an airbag body 501 and a plurality of airbags 502 provided in the airbag body 501. An air pump inflates the airbags 502 in the airbag sheet 50. During the process of holding objects with fingers, The distance between them is reduced, and the airbags in the airbag sheet 502 are pressed against each other, limiting the mutual proximity between adjacent fingers.

Referring to FIG. 9 , a plurality of piezoelectric ceramics 60 are provided on the flexible pad 30 . The piezoelectric ceramic 60 is disposed on the side of the flexible pad 30 that is in contact with the finger. After being energized, the piezoelectric ceramic 60 utilizes the inverse piezoelectric effect to vibrate at the corresponding part of the actual executor's finger, thereby transmitting tactile feedback information to the executor's finger.

In order to facilitate the piezoelectric ceramic 60 to better transmit vibration information to the fingers, it is preferred that the cross-section of the flexible pad 30 is arc-shaped.

In this embodiment, a first transition rod 403 is connected between the front-end connecting rod 201 and the front-end ferrule 401, and a second transition rod 404 is connected between the rear-end connecting rod 202 and the rear-end ferrule 402. The front-end connecting rod 201 It is convenient to pass the first transition rod 403 and the rear end link 202 to facilitate the finger movement through the second transition rod 404.

Please refer to Figure 11 and Figure 12. The driving mechanism includes two driving assemblies 101. Each driving assembly 101 includes a motor 102 and a support rod 103. The output end of the motor 102 is provided with a first gear 104. The two ends of the support rod 103 are respectively A second gear 105 and a bearing 106 are provided. The second gear 105 meshes with the first gear 104. The support rod 103 is fixedly connected to the front-end connecting rod 201. When the motor 102 is powered on and started, the output end drives the first gear 104 to rotate, the first gear 104 drives the second gear 105 to rotate, and then drives the front-end link 201 to rotate through the support rod 103, thereby adjusting the gap between the two front-end links 201. angle, distance and posture.

Specifically, please refer to Figures 5-8. The rear end of the front-end link 201 is provided with a notch 203, the front end of the rear-end link 202 is inserted into the notch 203, and the rear end of the front-end link 201 is connected with the front end of the rear-end link 202. A pin 204 is provided therebetween so that the rear end link 202 can freely rotate around the pin 204 .

In order to facilitate the energization of the motor 102, a wire 107 can be provided to connect with the motor 102.

The front end ferrule 401 is limited to the proximal phalanx of the finger, and the rear end ferrule 402 is limited to the middle phalanx of the finger.

Wear the feedback device to the index finger and middle finger of the performer, put the front end ferrule 401 of one of the link mechanisms 20 on the proximal phalanx 71 of the index finger, and put the rear end ferrule 402 on the middle phalanx 72 of the index finger. The front end ferrule 401 of a linkage mechanism 20 is placed at the proximal phalanx 73 of the middle finger, and the rear end ferrule 402 is placed at the middle phalanx 74 of the middle finger, so that the inner side of the index finger and the middle finger are close to the corresponding flexible pad 30, and the air bag piece 50 is placed Place it at the joint between the index finger and middle finger to ensure it is fixed on the finger, as shown in Figure 3.

The executor wears the feedback actuator. In the virtual environment world constructed by Unity3D software, when the index finger and middle finger of the executor's virtual model clamp an object, the clamping posture of the index finger and middle finger and the distance between the fingers are determined by the clamping position. The size of the object determines. When the virtual fingers hold an object, the object contacts the inner part of the virtual index finger and middle finger. The collision detection algorithm of the touch part transmits the contact signal to the Arduino signal control board through PC-side signal processing. The Arduino signal control board controls the The lines connected to the two motors 102 and the circuit connected to the air pump use the motors 102 to control the rotation angle and distance between the two front-end links 201 of the two link mechanisms 20, so that the link mechanisms 20 drive the fingers and The fingers move in the opposite direction of clamping. At the same time, the air pump inflates the air bags 502 in the air bag sheet 50. During the process of clamping the object, the distance between the fingers decreases, and the air bags 502 in the air bag sheet 50 squeeze each other. , limiting the mutual proximity between fingers. The linkage mechanism 20 drives the front-end ferrule 401 and the flexible pad 30 to cooperate with the air bag 502 to limit the mutual extrusion, and transmits the force feedback information caused by the executor's index finger and middle finger to hold the object.

Moreover, according to the distance posture between the index finger and the middle finger of the virtual model finger and the size of the clamped object in the virtual world, the distance and rotation angle between the two front-end links 201 can be adjusted, and the gas in the air bag 502 can be adjusted at the same time. The size can give feedback to the performer on the angle and posture of the finger gripping. When a person's fingers are bent to grasp an object or perform precise virtual operation training, the four fingers except the thumb will automatically move closer to each other when the fingers are bent. When the fingers are straightened, the distance between adjacent fingers will change. Increase. The device can feedback and limit the distance and posture between the fingers, thereby truly delivering force feedback information to the performer on the object held by the fingers.

In addition, since the piezoelectric ceramic 60 is attached to the flexible pad 30 close to the inner part of the finger, when the virtual finger holds an object, different parts of the inner finger contact the object, triggering the collision detection algorithm. The piezoelectric ceramic can, according to the signal transmitted by the collision detection algorithm, It is controlled by the circuit and uses the inverse piezoelectric effect to vibrate at the corresponding part of the actual executor's finger, which can transmit tactile feedback information to the executor's finger.

During the specific operation, the real index finger and the middle finger perform the action of contacting or grasping the object. This action causes the virtual index finger and the middle finger to contact or grasp the virtual object. When the index finger proximal phalanx module 1 and the middle finger proximal phalanx module 3 are both in contact with the virtual object. When the collision detection algorithm of the corresponding module is triggered, the corresponding two motors 102 are started, driving the real index finger and the middle finger to rotate away from each other, giving resistance to the real index finger and the middle finger to approach, thereby transmitting kinesthetic feedback, and at the same time communicating with the proximal phalanx 71 of the index finger. The piezoelectric ceramic 60 attached to the middle finger proximal phalanx 73 vibrates, providing tactile feedback when the index finger and middle finger touch the object; when the index finger middle phalanx module 2 and the middle finger middle phalanx module 4 both come into contact with the virtual object, the collision of the corresponding modules is triggered. The detection algorithm vibrates the piezoelectric ceramic 60 corresponding to the middle phalanx 72 of the index finger and the middle phalanx 74 of the middle finger of the real finger, and provides tactile feedback of the real index finger and middle finger; when the index finger proximal phalanx module 1, the index finger middle phalanx module 2, When the proximal phalanx module 3 of the middle finger and the middle phalanx module 4 of the middle finger are both in contact with the virtual object, the collision detection algorithm of the corresponding module is triggered, thereby starting the corresponding two motors 102 to provide resistance for the index finger and the middle finger to approach, giving the fingers Kinesthetic feedback, while vibrating the piezoelectric ceramics 60 corresponding to the proximal phalanx 71 of the index finger, the middle phalanx 72 of the index finger, the proximal phalanx 73 of the middle finger, and the middle phalanx 74 of the middle finger, giving tactile feedback to the index finger and the middle finger.

Claims (10)

A two-finger holding force tactile feedback device, which is characterized by including: Bearing seat; Driving mechanism, the driving mechanism is located in the bearing seat; The link structure includes two link mechanisms, each of the link mechanisms includes a movably connected front end link and a rear end link, and the drive mechanism can adjust the angle between the two front end links, so The rear end link can rotate relative to the front end link. The two-finger clamping force tactile feedback device according to claim 1, characterized in that each of the link mechanisms is connected to a limiter, and a flexible pad is provided on the limiter. The two-finger clamping force tactile feedback device according to claim 2, characterized in that the limiting member includes a front-end ferrule and a rear-end ferrule, and the front-end ferrule and the rear-end ferrule are respectively connected to the said On the front-end connecting rod and the rear-end connecting rod, the flexible pad is provided on the front-end ferrule and the rear-end ferrule. The two-finger clamping force tactile feedback device according to claim 4, characterized in that an air bag sheet is connected between the two flexible pads located at the front end. The two-finger clamping force tactile feedback device according to claim 2, wherein a plurality of piezoelectric ceramics are provided on the flexible pad. The two-finger holding force tactile feedback device according to claim 2, wherein the flexible pad has an arc-shaped cross-section. The two-finger clamping force tactile feedback device according to claim 3, wherein a first transition rod is connected between the front-end connecting rod and the front-end ferrule, and a first transition rod is connected between the rear-end connecting rod and the rear-end ferrule. There is a second transition bar connected between them. The two-finger clamping force tactile feedback device according to claim 1, characterized in that the driving mechanism includes two driving components, each of the driving components includes a motor and a support rod, and the output end of the motor is provided with There is a first gear, and second gears and bearings are respectively provided at both ends of the support rod. The second gear meshes with the first gear. The support rod is fixedly connected to the front end connecting rod. The two-finger clamping force tactile feedback device according to claim 1, wherein the rear end of the front-end link is provided with a notch, the front end of the rear-end link is inserted into the notch, and the front-end link is A pin is provided between the rear end of the rod and the front end of the rear end connecting rod. The two-finger clamping force tactile feedback device according to claim 3, wherein the front-end ferrule is limited to the proximal phalanx of the finger, and the rear-end ferrule is limited to the middle phalanx of the finger.