Visual tactile sensor

Abstract

The invention discloses a visual tactile sensor. The visual tactile sensor comprises a tactile element, an imaging element and a dimming assembly, the tactile element at least comprises a touch part which can generate elastic deformation under the action of external force. The imaging element is disposed corresponding to the haptic element to acquire an image of the haptic element. The dimming assembly comprises a light source and an optical structure. The light source is provided with a main light source directly facing the touch part and a secondary light source located on the periphery of the main light source. The optical structure is arranged between the light source and the tactile element and is provided with a light transmitting part, a light guiding part and a light reflecting part arranged between the light transmitting part and the light guiding part. The light-transmitting part directly faces the main light source, the light guide part is arranged on the periphery of the light-transmitting part in a surrounding mode and extends towards the secondary light source, and the light reflecting part is used for reflecting light in the light guide part so that the light can be gathered on the light-transmitting part. Through the main light source and the secondary light source, the light intensity at the touch part is improved, and the visual image shooting effect can be effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sensors, in particular to a visual-tactile sensor. BACKGROUND

[0002] When a robot perceives an external object, it needs to rely on a visual-tactile sensor. The visual-tactile sensor is a sensor that can convert visual images into tactile information, and can perceive information such as the shape and texture of the surface of an object, while measuring the contact force in the interaction.

[0003] The shell of the visual-tactile sensor is provided with a silica gel block and a transparent plate for supporting the silica gel block. The inside of the shell is also provided with a light source and a camera. The light source is used to provide light conditions for the camera to ensure the shooting effect of the visual image. However, in the prior art, the light source still has the problem of insufficient light intensity, which cannot improve the shooting effect of the visual image. SUMMARY

[0004] The main purpose of the present application is to provide a visual-tactile sensor, which aims to solve the problem of the shooting effect of the visual image being affected by the insufficient light intensity of the light source in the existing visual-tactile sensor.

[0005] To achieve the above-mentioned purpose, the present application provides a visual-tactile sensor, which comprises.

[0006] A tactile element, which at least includes a touch part capable of elastic deformation under the action of an external force; An imaging element, which is arranged corresponding to the tactile element to collect images of the tactile element; and A light adjusting assembly, which includes a light source and an optical structure. The light source has a main light source directly opposite the touch part, and a secondary light source located at the periphery of the main light source. The optical structure is arranged between the light source and the tactile element. The optical structure has a light transmission part, a light guide part, and a light reflection part arranged between the two. The light transmission part is directly opposite the main light source. The light guide part is annularly arranged at the periphery of the light transmission part and extends towards the secondary light source. The light reflection part is used to reflect the light in the light guide part, so that the light converges in the light transmission part.

[0007] Preferably, the light source includes a back plate and a light emitting part, and the light emitting part is arranged on the side surface of the back plate facing the tactile element. The optical structure is located on the side of the back plate facing the tactile element. The orthographic projection of the optical structure on the back plate is located within the range of the back plate and covers the light emitting part. The light emitting part includes the main light source and the secondary light source.

[0008] Preferably, the optical structure comprises a bottom plate and a surrounding plate, the bottom plate is arranged opposite to the main light source, the bottom plate is arranged in a light-transmitting manner and forms the light-transmitting part, the surrounding plate is annularly arranged at the outer circumferential side of the bottom plate and extends towards the side of the secondary light source, the surrounding plate forms the light guide part, a transition slope is arranged at the connection between the outer wall of the bottom plate and the outer wall of the surrounding plate, a reflective layer is arranged on the transition slope to form the light-reflecting part.

[0009] Preferably, the light guide part is arranged close to the outer periphery of the back plate, the orthographic projection of the light guide part on the back plate partially overlaps with the light-emitting part, and the light guide part is provided with an avoiding gap at the position overlapping with the light-emitting part.

[0010] Preferably, the visual and tactile sensor further comprises a housing, the housing has a one-side-opened accommodating cavity; The tactile element is arranged outside the housing, and the touch part is arranged corresponding to the opening; The light source is arranged in the accommodating cavity; The optical structure is arranged in the accommodating cavity and located between the light source and the tactile element, the light-transmitting part is arranged corresponding to the opening and is attached to the touch part.

[0011] Preferably, the inner wall profile of the accommodating cavity is matched with the outer peripheral profile shape of the optical structure; and / or, The tactile element is configured as a fingertip profile, comprising a finger palm and a finger edge annularly arranged at the periphery of the finger palm, the finger palm forms the touch part, and the bottom plate is arranged as an arc-shaped plate with the same curvature radius as that of the finger palm.

[0012] Preferably, the light guide part comprises four light guide plates annularly arranged at the four peripheral sides of the light-transmitting part, and two adjacent light guide plates are spaced apart at positions corresponding to the four corners of the light-transmitting part; The inner wall of the accommodating cavity is provided with at least one mounting column, the mounting column extends away from the tactile element, and the mounting column is located between two adjacent light guide plates and beyond the end of the light guide plate; The light source is connected to the mounting column.

[0013] Preferably, the outer side wall of the housing is provided with a groove at a position corresponding to the periphery of the opening; The tactile element is arranged in the groove and flush with the outer side wall of the housing.

[0014] Preferably, the light source comprises a back plate and a plurality of lamp beads, the plurality of lamp beads are arranged on the side surface of the back plate facing the tactile element, the plurality of lamp beads comprise a plurality of first lamp beads directly facing the light-transmitting part and a plurality of second lamp beads annularly arranged at the periphery of the plurality of first lamp beads. The main light source comprises the plurality of first lamp beads, and the secondary light source comprises the plurality of first lamp beads.

[0015] Preferably, the plurality of first lamp beads are configured as one of single-color lamp beads, double-color lamp beads or multi-color lamp beads; and / or, the plurality of second lamp beads are configured as one of single-color lamp beads, double-color lamp beads or multi-color lamp beads.

[0016] Preferably, in the plurality of lamp beads, every three lamp beads form a group, and the three lamp beads in the group are respectively configured as red lamp beads, green lamp beads and blue lamp beads.

[0017] Preferably, the haptic element has two opposite finger side edges in a first direction and a finger end in a second direction. On the back plate, the density of the lamp beads near the finger side edges is less than the density of the lamp beads near the opposite side of the finger end.

[0018] Preferably, the haptic element has two opposite finger side edges in a first direction and a finger end in a second direction. The secondary light source is arranged around three sides of the main light source and is respectively arranged corresponding to two finger side edges and the opposite side of the finger end. The light guide part comprises four light guide plates arranged around the four sides of the light transmission part, and the light reflection part is formed between each of the three light guide plates and the light transmission part, and the light reflection part corresponds to the secondary light source.

[0019] Preferably, at the four corners corresponding to the light transmission part, two adjacent light guide plates are arranged with a spacing therebetween.

[0020] Preferably, the light source is provided with a mounting hole at the center position thereof. The imaging element has a collection part, and the imaging element is arranged on the side of the light source away from the haptic element, and the collection part is exposed from the mounting hole to collect the image of the haptic element.

[0021] The technical solution provided by the present application has at least the following advantages: The present invention provides a visual-tactile sensor, comprising a tactile element, an imaging element, and a dimming assembly. The tactile element has a touch portion that can elastically deform under external force. The light source includes a main light source and a secondary light source located around the main light source, with the main light source facing the touch portion. The optical structure has a light-transmitting portion, a light-guiding portion, and a reflective portion disposed between the two. The light-transmitting portion faces the main light source, and the light-guiding portion is arranged around the periphery of the light-transmitting portion and extends towards the secondary light source. Light from the secondary light source is transmitted through the light-guiding portion to the reflective portion and reflected back to the light-transmitting portion, thereby achieving a supplementary lighting effect. By using the main and secondary light sources to increase the light intensity at the touch portion location, the visual image capture effect can be effectively improved. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0023] Figure 1 This is an exploded structural diagram of an embodiment of a visual-tactile sensor provided by the present invention; Figure 2 for Figure 1 A schematic diagram of the structure of the visual-tactile sensor with respect to the housing; Figure 3 for Figure 1 A schematic diagram of the structure of the visual-tactile sensor with respect to the dimming component; Figure 4 for Figure 3 An exploded view of the structure of the dimming component; Figure 5 for Figure 3 A cross-sectional view of the dimming component along AA; Figure 6 for Figure 3 A schematic diagram of the dimming component with respect to the light source; Figure 7 for Figure 3 A schematic diagram of the optical structure of the dimming component; Figure 8 for Figure 7 A schematic diagram of the optical structure (from another perspective); Figure 9 for Figure 7 Side view of the optical structure.

[0024] Explanation of icon numbers: 100 Visual-tactile sensor; 1 Tactile element; 11 Touch portion; 12 Finger pad; 13 Finger edge; 14 Finger tip; 2 Imaging element; 21 Acquisition unit; 3 Dimming assembly; 31 Light source; 31a Main light source; 31b Secondary light source; 311 Back plate; 312 Light-emitting part; 313 Lamp bead; 314 Mounting hole; 32 Optical structure; 321 Light-transmitting part; 322 Light guide part; 3221 Light guide plate; 323 Reflecting part; 324 Base plate; 325 Enclosure; 326 Transition slope; 327 Clearance notch; 4 Housing; 41 Receiving cavity; 42 Opening; 43 Mounting post; 44 Slot; F1 First direction; F2 Second direction.

[0025] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0028] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0029] When robots perceive external objects, they rely on visual-tactile sensors. A visual-tactile sensor is a sensor that can convert visual images into tactile information. It can sense information such as the shape and texture of an object's surface, and at the same time measure the contact force during interaction.

[0030] The housing of the visual tactile sensor has a silicone block and a transparent plate for supporting the silicone block. Inside the housing, there is also a light source and a camera. The light source is used to provide lighting conditions for the camera to ensure the shooting effect of the visual image.

[0031] To improve the light intensity at the location corresponding to the tactile element 1, the present invention improves the visual-tactile sensor 100. The structure of the visual-tactile sensor 100 will be described in detail below with reference to the accompanying drawings.

[0032] Please see Figure 1 and Figure 2 The visual-tactile sensor 100 includes a tactile element 1. It is understood that the tactile element 1 is used to contact an object. When the tactile element 1 acts on the object through operations such as grasping, applying pressure to the object, the object also exerts a reaction force on the tactile element 1. Under the action of this reaction force, the tactile element 1 undergoes elastic deformation, resulting in a change in the intensity of the reflected light to the light source 31. In other words, the tactile element 1 at least includes a touch portion 11 that can undergo elastic deformation under the action of external force.

[0033] The visual-tactile sensor 100 also includes an imaging element 2, which acquires images of the tactile element 1 that undergoes elastic deformation. Different reflected light intensities result in different images of the tactile element 1, so the acquired images can serve as carriers of tactile information, and tactile information can be obtained based on a preset image-to-tactile information mapping relationship.

[0034] Meanwhile, the visual tactile sensor 100 also includes a dimming component 3, which provides illumination to the tactile element 1, thereby increasing the brightness at the touch position 11. When the imaging element 2 acquires an image at the touch position 11, it can obtain a clear image, thereby improving the geometric reconstruction accuracy of the visual tactile sensor 100 on the object surface.

[0035] It is understandable that the imaging element 2 is used to acquire images at the location of the touch portion 11, so the acquisition portion 21 of the imaging element 2 is positioned toward the location of the touch portion 11.

[0036] Please see Figure 3 and Figure 4In this invention, the dimming assembly 3 includes a light source 31 and an optical structure 32. The light source 31 includes a main light source 31a and a secondary light source 31b. The main light source 31a faces the touch portion 11, and the secondary light source 31b is arranged around the main light source 31a. By adding a secondary light source 31b around the main light source 31a, not only can the coverage area of ​​the light source 31 be increased, but the arrangement of the light source 31 within a given space can also be made more reasonable.

[0037] Meanwhile, the optical structure 32 is disposed between the light source 31 and the tactile element 1. The optical structure 32 has a light-transmitting part 321, a light-guiding part 322 and a reflective part 323 disposed between the two. The light-transmitting part 321 faces the main light source 31a. The light-guiding part 322 is disposed around the periphery of the light-transmitting part 321 and extends toward the secondary light source 31b. The reflective part 323 is used to reflect the light in the light-guiding part 322 so that the light converges on the light-transmitting part 321.

[0038] The light-transmitting part 321 is positioned so that the main light source 31a is directly opposite the touch part 11, thereby allowing the light from the main light source 31a to pass through the light-transmitting part 321 and increasing the light intensity at the touch part 11. When the touch part 11 undergoes elastic deformation, the intensity of the reflected light from the main light source 31a changes, and this change can be captured by the imaging element 2 through the light-transmitting part 321.

[0039] Meanwhile, the light guide 322 is arranged around the periphery of the light-transmitting part 321 and extends toward the secondary light source 31b. The light from the secondary light source 31b is transmitted to the reflector 323 through the light guide 322 and reflected back to the light-transmitting part 321 by the reflector 323, thereby achieving the effect of supplementary lighting and further increasing the light intensity at the touch part 11, thereby effectively improving the visual image capture effect.

[0040] In one embodiment, please refer to Figure 4 and Figure 5 The light source 31 includes a back plate 311 and a light-emitting part 312. The light-emitting part 312 is disposed on the side surface of the back plate 311 facing the tactile element 1, and includes a main light source 31a and a secondary light source 31b. The optical structure 32 is located on the side of the back plate 311 facing the tactile element 1. The orthographic projection of the optical structure 32 on the back plate 311 is within the range of the back plate 311 and covers the light-emitting part 312.

[0041] In this embodiment, the orthographic projection of the optical structure 32 onto the back plate 311 is within the range of the back plate 311. This means that the lateral dimensions of the optical structure 32 and the back plate 311 are matched, with no redundant design exceeding the back plate 311, thus avoiding the occupancy of the limited space of the visual-touch sensor 100 due to a bulky structure. The light-emitting part 312 and the optical structure 32 are both integrated on the side of the back plate 311 facing the tactile element 1, thereby compactly stacking them in the vertical direction, reducing the vertical thickness of the components, and enabling the entire dimming assembly 3 to adapt to the miniaturization requirements of the visual-touch sensor 100, ensuring that the overall structure of the sensor is thin and light, without affecting the flexible operation of the visual-touch sensor 100.

[0042] Furthermore, the optical structure 32 covers the light-emitting part 312, meaning that the light emitted from the light-emitting part 312 can be completely enveloped or covered by the optical structure 32, preventing light leakage and improving light utilization. After the light is emitted from the light-emitting part 312, it can directly enter the optical structure 32, reducing the propagation path in the air and confining more light within the optical structure 32 for conduction, further improving light utilization and indirectly enhancing the illumination at the touch part 11.

[0043] The optical structure 32 covers the light-emitting part 312, ensuring that all the light from the secondary light source 31b enters the light guide part 322 and is transmitted to the reflector part 323 along a preset path. This makes the light-gathering function of the reflector part 323 more reliable and further enhances the light concentration of the light-transmitting part 321.

[0044] Specifically, please refer to Figure 5 and Figure 7 The optical structure 32 includes a base plate 324 and a surrounding plate 325. The base plate 324 is disposed opposite to the main light source 31a, and is light-transmitting, forming a light-transmitting portion 321. The surrounding plate 325 is arranged around the outer periphery of the base plate 324 and extends toward the secondary light source 31b, forming a light-guiding portion 322. A transition slope 326 is provided at the connection between the outer wall of the base plate 324 and the outer wall of the surrounding plate 325, and a reflective layer is provided on the transition slope 326 to form a reflective portion 323.

[0045] In this embodiment, the base plate 324, serving as the light-transmitting part 321, is made of a high-transmittance material, such as PMMA (Polymethyl Methacrylate), with a transmittance of up to 92%, ensuring that the light from the main light source 31a penetrates unobstructed to the touch part 11. The surrounding plate 325, serving as the light-guiding part 322, can be made of a high-refractive-index light-guiding material, such as PC (Polycarbonate), with a refractive index of 1.58, thereby enhancing the confinement and transmission of light from the secondary light source 31b. By functionally partitioning the optical structure 32, the material properties of different areas are precisely matched with functional requirements, reducing light loss. Furthermore, the surrounding plate 325 extends towards the secondary light source 31b, forming a wraparound enclosure of the secondary light source 31b, maximizing the direct entry of light from the secondary light source 31b into the interior of the surrounding plate 325, minimizing light leakage loss.

[0046] Meanwhile, a transition slope 326 is provided at the connection between the outer wall of the base plate 324 and the outer wall of the surrounding plate 325. A reflective layer is formed on the transition slope 326 by vacuum deposition, for example, an aluminum film is formed on the transition slope 326, so that the light reflectivity of the reflective part 323 reaches 95%. Thus, the light in the light guide part 322 is reflected by the reflective part 323. The reflected light converges at the light transmission part 321, thereby increasing the light intensity at the touch part 11. The reflective layer also plays a physical isolation role, avoiding diffuse reflection of light at the reflective part 323 due to the abrupt change in the refractive index of the material, so that the light can enter the light transmission part 321 along a preset path after reflection, reducing stray light interference.

[0047] Furthermore, the frame structure formed by the base plate 324 and the surrounding plate 325 can improve the bending strength of the optical structure 32, thereby reducing the deformation of the optical structure 32 when the tactile element 1 is under pressure, and avoiding optical path deviation caused by the deformation of the optical structure 32. The integrated structure of the base plate 324 and the surrounding plate 325 can further reduce the spatial volume of the optical structure 32, thereby reducing the volume ratio of the dimming component 3 within the visual tactile sensor 100.

[0048] In one embodiment, please refer to Figure 5 The light guide portion 322 is disposed near the outer periphery of the back plate 311. The orthographic projection of the light guide portion 322 on the back plate 311 partially overlaps with the light-emitting portion 312. An avoidance notch 327 is provided at the position where the light guide portion 322 overlaps with the light-emitting portion 312.

[0049] In this embodiment, the light guide portion 322 and the light-emitting portion 312 partially overlap, so that the light emitted by the light-emitting portion 312 is closer to the incident area of ​​the light guide portion 322, thereby allowing more light to directly enter the interior of the light guide portion 322 instead of scattering to the surrounding space, thereby improving the coupling efficiency of light from the light-emitting portion 312 to the light guide portion 322.

[0050] The light guide 322 has an avoidance notch at the position where it overlaps with the light-emitting part 312. This prevents the light guide 322 from directly covering the light-emitting surface of the light-emitting part 312, avoiding light absorption or reflection by the material of the light guide 322 itself due to obstruction. This ensures that the light from the light-emitting part 312 can reach the effective incident area of ​​the light guide 322 without obstruction, or directly participate in illumination. On the other hand, it achieves close cooperation between the light guide 322 and the light-emitting part 312 within a limited space, eliminating the need to reserve an excessive gap between them, and further reducing the overall structural thickness.

[0051] Please see Figure 1 and Figure 2 In one embodiment, the visual-tactile sensor 100 further includes a housing 4, which has a receiving cavity 41 with an opening 42 on one side. A tactile element 1 is disposed on the outside of the housing 4, and a touch portion 11 is disposed corresponding to the opening 42. A light source 31 is disposed in the receiving cavity 41. An optical structure 32 is disposed in the receiving cavity 41 and is located between the light source 31 and the tactile element 1, with a light-transmitting portion 321 disposed corresponding to the opening 42 and attached to the touch portion 11.

[0052] In this embodiment, the visual-tactile sensor 100 further includes a housing 4, which has a receiving cavity 41 with an opening 42 on one side. The light source 31 and the optical structure 32 are both disposed within the receiving cavity 41. The light source 31 and the optical structure 32 are enclosed within the receiving cavity 41 and interact with the external tactile element 1 only through the opening 42, effectively preventing dust and liquid from directly contacting the internal components. Simultaneously, while the tactile element 1 directly contacts the object, the rigid support of the housing 4 buffers external impact forces, such as the instantaneous collision force generated when grasping an object, preventing displacement of the internal components due to vibration or impact.

[0053] Meanwhile, the tactile element 1 is located on the outside of the housing 4, and the touch portion 11 is positioned corresponding to the opening 42. The light-transmitting portion 321 is positioned corresponding to the opening 42 and is attached to the touch portion 11. The attachment of the light-transmitting portion 321 to the touch portion 11 eliminates the air layer between them, which not only avoids light reflection loss at the interface and improves light utilization, but also avoids stray halo caused by light scattering due to the air gap between them, thus making the image of the deformed edge of the contact portion clearer. Moreover, the attachment of the touch portion 11 to the light-transmitting portion 321 through the opening 42 allows the deformation energy to be transmitted by the light-transmitting portion 321 in real time, ensuring that the image captured by the imaging element 2 is basically synchronized with the actual deformation, and avoiding the problem of lag between deformation and imaging.

[0054] Furthermore, the correspondence between the opening 42 and the light-transmitting portion 321 not only ensures that the light from the main light source 31a has a directional transmission path, guaranteeing that more light is used to illuminate the touch portion 11 of the tactile element 1, thereby increasing the effective light intensity, but also ensures that the area of ​​the touch portion 11 observed by the imaging element 2 through the optical structure 32 remains stable, improving the repeatability accuracy of deformation measurement.

[0055] The present invention does not impose specific limitations on the structure of the tactile element 1. In one embodiment, the touch portion 11 of the tactile element 1 is arranged in a flat plate shape. In another embodiment, in order to more accurately mimic human actions such as grasping with fingertips and to acquire tactile information obtained by human fingertips during grasping operations, the tactile element 1 is configured to mimic fingertips, including a fingertip 12 and a finger edge 13 surrounding the fingertip 12. Furthermore, based on human grasping actions, it is known that the grasping task is usually completed using the fingertip 12; therefore, at least the fingertip 12 is configured to be elastically deformable, forming the touch portion 11.

[0056] In order to ensure that the elastic deformation at the fingertip 12 position can be clearly seen from the light-transmitting part 321, in one embodiment, the base plate 324 is configured as an arc plate, and its radius of curvature is the same as that of the fingertip 12.

[0057] In one embodiment, the inner wall contour of the receiving cavity 41 is adapted to the outer peripheral contour shape of the optical structure 32. It is understood that the light transmission by the light guide 322, the light reflection by the reflective slope, and the light convergence by the light transmission part 321 are all related to the relative positional accuracy of the optical structure 32, the light source 31, and the tactile element 1. The adaptation of the inner wall contour of the receiving cavity 41 to the outer peripheral contour shape of the optical structure 32 allows the inner wall of the receiving cavity 41 to act as a limiting element, preventing displacement of the optical structure 32 within the receiving cavity 41, thereby ensuring a unique light transmission path and thus guaranteeing the stability of the supplementary lighting effect.

[0058] Meanwhile, the inner wall contour of the receiving cavity 41 is adapted to the outer peripheral contour shape of the optical structure 32, so that the outer periphery of the optical structure 32 fits snugly against the inner wall of the receiving cavity 41, eliminating gaps that may exist in non-fitting designs, thus making the optical structure 32 and the housing 4 fit tightly together. Moreover, the shape adaptation ensures that the outer periphery of the optical structure 32 fits snugly against the inner wall of the receiving cavity 41, thereby forming multi-directional support, dispersing external impact forces throughout the housing 4, and preventing excessive local stress on the optical structure 32 during gripping.

[0059] It should be noted that the above two technical features can be set individually or simultaneously. Specifically, in one embodiment, the above two technical features are set simultaneously. That is, the outer contour of the light-transmitting part 321 is adapted to the outer contour shape of the fingertip 12. At the same time, the base plate 324 is set as an arc plate, and its radius of curvature is the same as that of the fingertip 12, and the inner wall contour of the receiving cavity 41 is adapted to the outer peripheral contour shape of the optical structure 32.

[0060] Continuing from the above, a transition slope 326 is provided at the connection between the outer wall of the base plate 324 and the outer wall of the surrounding plate 325. A reflective layer is provided on the transition slope 326 to form a reflective portion 323. In order to ensure that the light from the secondary light source 31b can reach the light-transmitting portion 321 after being reflected by the reflective portion 323, in one embodiment, please refer to... Figure 7 and Figure 9 The included angle θ1 between the outer wall of the enclosure 325 and the transition slope 326 is set to 105°~120°, and the included angle θ2 between the outer wall of the bottom plate 324 and the transition slope 326 is set to 105°~120°.

[0061] The light from the secondary light source 31b enters the light guide section 322 perpendicularly. The function of the light guide section 322 is to transmit the light from the secondary light source 31b to the transition slope 326. The angle θ1 between the light guide section 322 and the transition slope 326 determines the incident angle of the light as it travels from the light guide section 322 to the transition slope 326. The incident angle α1 when the light travels to the transition slope 326 is 180° - θ1. When θ1 is set to 105°~120°, α1 corresponds to 60°~75°. When the incident angle α1 is between 60° and 75°, the specular reflection rate of the transition slope 326 reaches over 90% (diffuse reflection rate <10%), which can minimize the energy loss of light during reflection, thereby improving the light transmission efficiency from the light guide section 322 to the transition slope 326.

[0062] Meanwhile, when the incident angle α1 is between 60° and 75°, when the light is reflected by the transition slope 326 and shines on the light-transmitting part 321, the reflection angle α2 is equal to the incident angle α1. At this time, the angle θ2 between the light-transmitting part 321 and the transition slope 326 determines the tilt relationship between the light-transmitting part 321 and the transition slope 326. When θ2 is set to 105° to 120°, when the reflected light reaches the light-transmitting part 321, the angle between the reflected light and the light-transmitting part 321 is 30° to 45°. At this time, when the light reaches the light-transmitting part 321, it concentrates and covers the fingertip 12 area, thereby increasing the light brightness at the fingertip 12 position.

[0063] If the angle θ1 between the light guide 322 and the transition slope 326, and the angle θ2 between the light transmittance 321 and the transition slope 326 are too small (e.g., less than 105°), the convergence angle of the reflected light will be too steep, which will cause the light to be excessively concentrated at the center of the fingertip 12, thus forming a spot effect. This will result in a large difference in brightness between the center and the edge of the fingertip 12, which is not conducive to the imaging element 2 acquiring a clear visual image.

[0064] If the angle θ1 between the light guide 322 and the transition slope 326, and the angle θ2 between the light transmittance 321 and the transition slope 326 are too small (e.g., greater than 120°), the divergence angle of the reflected light will be too large, and some light will exceed the range of the fingertip 12 (illuminating the finger edge 13), resulting in insufficient brightness at the fingertip 12 and poor supplementary lighting effect.

[0065] The angle θ1 between the light guide part 322 and the transition slope 326, and the angle θ2 between the light transmittance part 321 and the transition slope 326 are set to a range of 105°~120°, so that the reflected light falls at a suitable point and matches the arc surface of the fingertip 12, thereby uniformly improving the brightness at the position of the fingertip 12 and achieving uniform illumination of the entire area.

[0066] In one embodiment, please refer to Figure 2 and Figure 8 The light guide section 322 includes four light guide plates 3221 arranged around the light-transmitting section 321. At the four corners of the corresponding light-transmitting section 321, adjacent light guide plates 3221 are spaced apart. At least one mounting post 43 protrudes from the inner wall of the receiving cavity 41. The mounting post 43 extends away from the tactile element 1 and is located between adjacent light guide plates 3221, extending beyond the ends of the light guide plates 3221. The light source 31 is connected to the mounting post 43.

[0067] In this embodiment, the light guide portion 322 includes four light guide plates 3221 arranged around the light-transmitting portion 321. At the four corners of the corresponding light-transmitting portion 321, adjacent light guide plates 3221 are spaced apart. The spaced-apart arrangement of adjacent light guide plates 3221 provides space for the mounting post 43, avoiding the need to create additional space for the light source 31 within the receiving cavity 41, thereby making the assembly of the optical structure 32 and the light source 31 more compact.

[0068] Meanwhile, the mounting post 43 protrudes from the inner wall of the receiving cavity 41, forming an integrated rigid structure with the housing 4, thereby improving the installation strength of the mounting post 43. The light source 31 is connected to the mounting post 43, for example, by plugging it into the mounting post 43 or by screwing it into the mounting post 43. Since the mounting post 43 extends beyond the end of the light guide plate 3221, a non-contact support is formed between the light source 31 and the light guide plate 3221. Even if the light guide plate 3221 undergoes a slight displacement due to the deformation of the tactile element 1, it will not be transmitted to the light source 31, avoiding positional displacement caused by rigid collision between the light source 31 and the light guide plate 3221, and ensuring the stability of the optical path during long-term use.

[0069] And, please see Figure 1 A groove 44 is provided on the outer wall of the housing 4 at the position corresponding to the periphery of the opening 42. The tactile element 1 is disposed in the groove 44 and is flush with the outer wall of the housing 4.

[0070] Understandably, the tactile element 1 is the component that directly contacts the object. If the tactile element 1 protrudes from the outer wall of the housing 4, uneven force at the edges can easily lead to excessive local deformation when in contact with the object, distorting the deformation image. If it is recessed into the housing 4, the effective contact area between the tactile element 1 and the object may be reduced due to obstruction at the edges of the housing 4. A flush design ensures that the tactile element 1 and the outer wall of the housing 4 form a continuous, flat surface, resulting in uniform force and a complete contact area when in contact with the object. This allows the deformation of the tactile element 1 to accurately reflect the contact state of the object, improving the matching degree between the deformation image captured by the imaging element 2 and the actual contact.

[0071] Meanwhile, the tactile element 1 is mostly made of flexible materials, such as silicone. Since the tactile element 1 is directly exposed, it is easily damaged by collisions and scratches. The groove 44 is designed to form a circumferential protective barrier. The groove 44 is arranged around the periphery of the opening 42, and its inner wall can surround the edge of the tactile element 1. When the sensor accidentally collides with a hard object, the edge of the groove 44 of the housing 4 will contact the external force first, reducing the impact force directly borne by the tactile element 1 and preventing permanent damage such as tearing and denting. Moreover, the cooperation between the groove 44 and the tactile element 1 can limit its excessive deformation and prevent fatigue failure caused by deformation exceeding the material's elastic limit.

[0072] In one embodiment, please refer to Figure 4 and Figure 6The light source 31 includes a back plate 311 and a plurality of LED beads 313, which are disposed on the side surface of the back plate 311 facing the tactile element 1. The plurality of LED beads 313 includes a plurality of first LED beads facing the light-transmitting portion 321 and a plurality of second LED beads surrounding the plurality of first LED beads. The main light source 31a includes a plurality of first LED beads, and the secondary light source 31b includes a plurality of first LED beads.

[0073] This invention does not specifically limit the color of the first LED. Multiple first LEDs can be configured as monochrome, dual-color, or multi-color LEDs. That is, the first LEDs can be set as monochrome LEDs, for example, multiple first LEDs can be set as white LEDs, or as a single colored LED. Multiple first LEDs can be set as dual-color LEDs, for example, multiple first LEDs can be set as two different colored LEDs. Multiple first LEDs can also be set as multi-color LEDs, for example, multiple first LEDs can be set as tri-color LEDs, with each group of three colored LEDs forming a set.

[0074] This invention does not specifically limit the color of the second LED. Multiple second LEDs can be configured as monochrome, dual-color, or multi-color LEDs. That is, the second LEDs can be set as monochrome LEDs, for example, multiple second LEDs can be set as white LEDs, or as a single colored LED. Multiple second LEDs can be set as dual-color LEDs, for example, multiple second LEDs can be set as two different colored LEDs. Multiple second LEDs can also be set as multi-color LEDs, for example, multiple second LEDs can be set as tri-color LEDs, with each group of three colored LEDs forming a set.

[0075] It should be noted that the above two technical features can be set individually or simultaneously. Specifically, in one embodiment, both technical features are set simultaneously.

[0076] This invention does not impose specific limitations on the colors of the first and second LED chips. The first and second LED chips can be the same or different colors. In one embodiment, the first and second LED chips are the same color. This simplifies the structure of the light source 31.

[0077] In one embodiment, among the plurality of LED beads 313, every three LED beads 313 form a group, and the three LED beads 313 in a group are respectively configured as red LED beads, green LED beads and blue LED beads.

[0078] In the above structure, the tactile element 1 is configured as a fingertip-shaped element, including a fingertip 12 and a finger edge 13 surrounding the fingertip 12. It can be understood that the fingertip-shaped tactile element 1 has two opposing finger sides in the finger width direction and opposing finger tips and finger roots in the finger length direction, with the finger roots typically connected to the palm. It should be noted that the finger width direction corresponds to the first direction F1, and the finger length direction corresponds to the second direction F2.

[0079] Understandably, during the grasping process using the fingertip 12, in order to improve grasping stability, the grasping position is usually set close to the base of the finger, that is, away from the fingertip. Furthermore, the center position of the fingertip 12 and the position near the side of the finger are high-frequency deformation areas when in contact with an object.

[0080] In one embodiment, on the back plate 311, the density of LED beads 313 near the finger side is less than the density of LED beads 313 on the opposite side of the fingertip.

[0081] Understandably, the deformation frequency at the center of the fingertip 12 and the opposite side of the fingertip is higher than that near the fingertip side. By setting the density of LED beads 313 near the fingertip side to be lower than that on the opposite side of the fingertip, the light intensity is positively correlated with the contact frequency. The opposite side of the fingertip receives sufficient light through high-density LED beads 313, while the fingertip side receives basic illumination through low-density LED beads 313, thus reducing redundant energy consumption while meeting the lighting requirements.

[0082] Meanwhile, the differentiated arrangement of the 313 LEDs ensures that the light intensity on the opposite side of the fingertip is higher than that on the side of the finger, which not only guarantees the imaging clarity of the large deformation area and improves the detail recognition rate, but also avoids the reflection interference in the small deformation area.

[0083] Furthermore, if the density of the LED beads 313 is uniform, a complex optical structure 32 (such as adding a light-shielding plate and a diffuser) is required to adjust the light intensity in different areas, which makes the structure of the dimming component 3 complex. However, by using a differentiated arrangement of the LED beads 313, the brightness ratio of the opposite side of the fingertip and the side of the finger can be directly matched with the imaging requirements, simplifying the structure of the dimming component 3 and reducing the overall cost of the sensor.

[0084] As mentioned above, in order to improve gripping stability during the grasping process using the fingertip 12, the gripping position is usually close to the base of the finger, that is, away from the fingertip. Furthermore, the center position of the fingertip 12 and the position near the side of the finger are high-frequency deformation areas when in contact with an object.

[0085] Therefore, in order to effectively improve the visual image capture effect, the position of the secondary light source 31b needs to be adjusted according to the actual application scenario. The secondary light source 31b is arranged around the three sides of the main light source 31a, corresponding to the two finger sides and the fingertip. In other words, the secondary light source 31b is arranged around the three sides of the main light source 31a, corresponding to the two finger sides and the finger base, thus accurately covering the highly sensitive contact area of ​​the tactile element 1 and improving the supplementary lighting effect.

[0086] Continuing from the above, among the multiple LEDs 313, every three LEDs 313 form a group, and the three LEDs 313 in a group are respectively configured as red, green, and blue LEDs. In one embodiment, at the four corners of the corresponding light-transmitting portion 321, adjacent light guide plates 3221 are spaced apart. In this way, the light from the secondary light source 31b at different positions is conducted through the independent light guide plates 3221, and the light does not directly overlap at the corners of the light-transmitting portion 321, avoiding light mixing, thereby improving the purity of the light color, and thus ensuring that the image captured by the imaging element 2 is free from color interference.

[0087] Please see Figure 5 and Figure 6 Imaging element 2 is used to acquire an image at the fingertip 12 position, therefore the acquisition part 21 of imaging element 2 is positioned towards the fingertip 12 position. To facilitate imaging element 2 in acquiring images at the fingertip 12 position, in one embodiment, please refer to... Figure 1 The light source 31 has a mounting hole 314 at its center position. The imaging element 2 has a collection part 21, which is located on the side of the light source 31 away from the tactile element 1, and the collection part 21 is exposed from the mounting hole 314 to collect the image of the tactile element 1.

[0088] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A visual-tactile sensor, characterized in that, include: A tactile element, including at least a touch portion that can undergo elastic deformation under the action of external force; An imaging element is provided corresponding to the tactile element to acquire an image of the tactile element; as well as, A dimming assembly includes a light source and an optical structure. The light source has a main light source facing the touch area and a secondary light source located around the main light source. The optical structure is disposed between the light source and the tactile element. The optical structure has a light-transmitting part, a light-guiding part, and a reflective part disposed between the two. The light-transmitting part faces the main light source. The light-guiding part is arranged around the periphery of the light-transmitting part and extends toward the secondary light source. The reflective part is used to reflect the light in the light-guiding part so that the light converges on the light-transmitting part.

2. The visual-tactile sensor according to claim 1, characterized in that, The light source includes a back plate and a light-emitting part, the light-emitting part being disposed on the side surface of the back plate facing the tactile element; The optical structure is located on the side of the back plate facing the tactile element, and the orthographic projection of the optical structure on the back plate is within the range of the back plate and covers the light-emitting part; The light-emitting part includes the main light source and the secondary light source.

3. The visual-tactile sensor according to claim 2, characterized in that, The optical structure includes a base plate and a surrounding plate. The base plate is disposed opposite to the main light source and is light-transmitting, forming the light-transmitting part. The surrounding plate is arranged around the outer periphery of the base plate and extends toward the secondary light source, forming the light guide part. A transition slope is provided at the connection between the outer wall of the base plate and the outer wall of the surrounding plate, and a reflective layer is provided on the transition slope to form the reflective part.

4. The visual-tactile sensor according to claim 3, characterized in that, The light guide portion is disposed near the outer periphery of the back plate, and the orthographic projection of the light guide portion on the back plate partially overlaps with the light-emitting portion. The light guide portion is provided with an avoidance notch at the position where it overlaps with the light-emitting portion.

5. The visual-tactile sensor according to claim 1, characterized in that, The visual-tactile sensor also includes a housing having a receiving cavity with an opening on one side; The tactile element is disposed on the outside of the housing, and the touch portion is disposed corresponding to the opening; The light source is disposed in the receiving cavity; The optical structure is disposed in the receiving cavity and located between the light source and the tactile element, and the light-transmitting part is disposed corresponding to the opening and is attached to the touch part.

6. The visual-tactile sensor according to claim 5, characterized in that, The inner wall contour of the receiving cavity is adapted to the outer peripheral contour shape of the optical structure; and / or, The tactile element is configured to mimic a fingertip, including a fingertip and a finger edge surrounding the fingertip. The fingertip forms the touch portion. The base plate is configured as an arc-shaped plate with the same radius of curvature as the fingertip.

7. The visual-tactile sensor according to claim 5, characterized in that, The light guide portion includes four light guide plates arranged around the light-transmitting portion, and at the four corners corresponding to the light-transmitting portion, adjacent light guide plates are spaced apart. The inner wall of the receiving cavity has at least one mounting post protruding, the mounting post extending toward the side away from the tactile element, the mounting post being located between two adjacent light guide plates and extending beyond the end of the light guide plate; The light source is connected to the mounting column.

8. The visual-tactile sensor according to claim 5, characterized in that, The outer wall of the housing is provided with a groove at a position corresponding to the periphery of the opening; The tactile element is disposed in the groove and is flush with the outer wall of the housing.

9. The visual-tactile sensor according to claim 1, characterized in that, The light source includes a back plate and a plurality of LED beads. The plurality of LED beads are disposed on the side surface of the back plate facing the tactile element. The plurality of LED beads include a plurality of first LED beads facing the light-transmitting part and a plurality of second LED beads surrounding the plurality of first LED beads. The main light source includes the plurality of first LED beads, and the secondary light source includes the plurality of first LED beads.

10. The dimming component according to claim 9, characterized in that, The plurality of first LED beads are configured as one of monochrome LED beads, dual-color LED beads, or multi-color LED beads; and / or, The plurality of second LEDs are configured as one of monochrome LEDs, dual-color LEDs, or multi-color LEDs.

11. The dimming assembly according to claim 10, characterized in that, Among the plurality of LED beads, every three LED beads form a group, and the three LED beads in a group are respectively configured as red LED beads, green LED beads and blue LED beads.

12. The dimming assembly according to claim 9, characterized in that, The tactile element has two opposing finger sides in a first direction and a finger tip in a second direction; On the back plate, the density of LED beads near the finger side is less than the density of LED beads on the opposite side of the fingertip.

13. The visual-tactile sensor according to claim 1, characterized in that, The tactile element has two opposing finger sides in a first direction and a finger tip in a second direction; The secondary light source ring is disposed on three sides of the main light source, and is respectively positioned corresponding to the two finger sides and opposite to the fingertip; The light guide portion includes four light guide plates arranged around the light-transmitting portion, and three of the light guide plates form the reflective portion between themselves and the light-transmitting portion, with the reflective portion corresponding to the secondary light source.

14. The dimming assembly according to claim 13, characterized in that, At the four corners corresponding to the light-transmitting part, two adjacent light guide plates are spaced apart.

15. The visual-tactile sensor according to claim 1, characterized in that, The light source has a mounting hole at its center position; The imaging element has a acquisition section, which is located on the side of the light source away from the tactile element, and the acquisition section is exposed from the mounting hole to acquire an image of the tactile element.

Images