Finger Surface Research Articles

Structure of human DPPA3 bound to the UHRF1 PHD finger reveals its functional and structural differences from mouse DPPA3

DNA methylation maintenance is essential for cell fate inheritance. In differentiated cells, this involves orchestrated actions of DNMT1 and UHRF1. In mice, the high-affinity binding of DPPA3 to the UHRF1 PHD finger regulates UHRF1 chromatin dissociation and cytosolic localization, which is required for oocyte maturation and early embryo development. However, the human DPPA3 ortholog functions during these stages remain unclear. Here, we report the structural basis for human DPPA3 binding to the UHRF1 PHD finger. The conserved human DPPA3 85VRT87 motif binds to the acidic surface of UHRF1 PHD finger, whereas mouse DPPA3 binding additionally utilizes two unique α-helices. The binding affinity of human DPPA3 for the UHRF1 PHD finger was weaker than that of mouse DPPA3. Consequently, human DPPA3, unlike mouse DPPA3, failed to inhibit UHRF1 chromatin binding and DNA remethylation in Xenopus egg extracts effectively. Our data provide novel insights into the distinct function and structure of human DPPA3.

Research on Convex Fiber Grating Tactile Sliding Sensor Based on Mechanical Fingers.

In order to solve the problem of flexible sliding tactile composite sensing in the actual grasp of intelligent robot fingers, this paper proposes a research on a convex fiber grating tactile sliding sensor based on mechanical fingers. Based on the sensing principle of fiber Bragg grating, 3D printing technology was used to encapsulate the FBG sensor array with elastic 50 A resin, a double-layer "hemispherical cuboid" distributed sensing unit was designed, and the FBG slippery tactile sensor was actually pasted on the surface of the mechanical finger for static and dynamic experiments. The experimental results show that the slippery tactile sensor designed in this paper has a good linear relationship with temperature and strain. The temperature sensitivities of the polymer-packaged FBGs are KT1 = 13.04 pm/°C and KT2 = 12.91 pm/°C, and they have a pressure sensitivity of 40.4 pm/N and 31.2 pm/N, respectively. The FBG sliding tactile sensor not only realizes the identification of the sliding signal generation point and the end point but also completes the classification and identification of sandpaper, cardboard, and polypropylene plastic, and it has a high degree of fit with the robot finger, which has certain application value for the intelligent robot sliding tactile signal perception.

Experimental investigation of wax deposition on multiple steel alloys

Paraffin wax deposition is a flow assurance issue that occurs frequently in subsea crude oil and gas condensate flowlines and pipelines. While some mitigation techniques involve coatings, most wax deposition in the oil and gas industry occurs on bare pipe walls made of various steel alloys. Previously, there has not been any investigation into the possibility of differences in the wax deposition that could be attributed to the different types of steel alloys, and this study set out to fill that gap. A cold finger apparatus with interchangeable fingers was used to generate deposits. Deposits were created from waxy model oils across several bulk oil temperatures and rotational speeds. To cover a wide array of materials, six different steels were tested: A2, A36, 1018, 4130, 304, and 316. These materials range from low-carbon steels to high-chrome content stainless steels. Each cold finger's surface was finished with the same process to create a roughness of 4.6 ± 0.5 mm. Deposit mass, thickness, and composition all showed non-negligible differences between deposits formed on the steels investigated: masses varied by 5–15%, thicknesses varied by 30% or more, and deposit compositions were noticeably skewed. Alloy composition, contact angle, roughness, and thermal conductivity were discussed as possible indicators of the effects an alloy would have on wax deposition. These findings facilitate the comparison and interpretation of the results from wax research literature using different steel alloys as well as the design of laboratory wax testing that more closely resembles field conditions.

Unusual localization of a digital neurofibroma: About a case and review of the literature

Neurofibromas are benign tumors of peri-nervous origin. may occur as a single lesion (solitary neurofibroma) or as part of a neurofibromatosis type 1. We present a case of a 44-year-old man with a painful neurofibroma on the dorsal surface of the 3rd right finger, revealed by a painful mass on its posterolateral aspect. Treatment was by excisional biopsy, with histopathological examination confirming the diagnosis. In the study by Lincoski et al, 24 benign nerve tumours accounted for 11.5% of the total number of soft-tissue tumours in the hand and forearm. Isolated neurofibromas are rare in the hand and normally grow slowly over many years. MRI provides precise information on the anatomical relationships of the tumour. Even with a correct diagnosis, the therapeutic decision must be carefully considered.

E034 Drug-induced accelerated nodulosis in a patient with rheumatoid arthritis

Abstract Background/Aims Drug-induced accelerated nodulosis (DIAN) is characterized by the occurrence or progression of multiple subcutaneous nodules in a patient treated for rheumatoid arthritis (RA). It was first and most commonly reported with methotrexate in RA patients. Methods A 37-year-old normotensive, non-diabetic, seropositive rheumatoid arthritis female presented with complaints of nodules over the bilateral hands and feet from the last three months. The treatment history included methotrexate therapy (10 mg/week) for one year. Methotrexate-induced rheumatoid accelerated nodulosis (MIAN) was suspected. Methotrexate was stopped and hydroxychloroquine was added considering the low disease activity. The nodules decreased in number as well as size. On follow-up, she presented with increased multiple joint pain and swelling with ESR 60 mm/hour, CRP 13.6 mg/L, and leflunomide was added. After six months of leflunomide use, she again developed multiple bilateral nodules on the extensor and palmar surface of fingers and feet, ranging from 0.5 to 1 cm. The CRP was 9.2 mg/L, ESR 80 mm/hour, complete blood count showed mild anaemia with normal renal and liver function tests. The nodule biopsy showed palisading granuloma consisting of lymphocytes and histiocytes in mid and deep reticular dermis with large foci of fibrin deposition and collagen degeneration s/o rheumatoid nodule. Leflunomide was stopped. Results The leflunomide was switched to sulfasalazine along with colchicine, and hydroxychloroquine was continued. The patient is doing well on follow-up in terms of disease activity and nodule size. Palmeiro. A.G., et al. 2022 reviewed 39 studies from 1st Jan 1988 to 1st Jan 2022 and found 109 cases of accelerated nodulosis. 99 patients had RA, methotrexate was the culprit drug in 89, followed by etanercept in 7 and leflunomide was in just 3 patients. Although there are no exact treatment guidelines, tumour necrosis factor inhibitors were avoided due to increased nodulosis risk. Recently, Valor-Méndez. L., et al 2020 reported improved nodulosis with Janus Kinase inhibitors like baricitinib, which seems to be a future option. Histologically, rheumatoid nodules and accelerated nodulosis are indistinguishable. The exact pathogenesis is unknown but, polymorphic variants of methionine synthase reductase or haplotype HLA-DRB1*0401, and adenosine A1 receptor promotion in multinucleated giant cells are associated. Conclusion Drug-induced accelerated nodulosis (DIAN) and MIAN are not that rare but diagnosis is challenging. It causes significant morbidity and affects the quality of life because of the predominant involvement of hands and feet. It should be suspected especially when disease activity is low or rapidly progressive nodules with a change in immunotherapy. Partial to total improvement can be achieved by identifying and stopping the culprit drug. We need specific guidelines, more treatment options, and a specific national registry to report such adverse effects with biologics and non-biologic disease-modifying antirheumatic drugs. Disclosure H. Singh: None. R. Kaur: None. G. Mohan: None.

The Impact of Illumination on Finger Vascular Pattern Recognition

This paper studies the impact of illumination direction and bundle width on finger vascular pattern imaging and recognition performance. A qualitative theoretical model is presented to explain the projection of finger blood vessels on the skin. A series of experiments were conducted using a scanner of our design with illumination from the top, a single-direction side (left or right), and narrow or wide beams. A new dataset was collected for the experiments, containing 4,428 NIR images of finger vein patterns captured under well-controlled conditions to minimize position and rotation angle differences between different sessions. Top illumination performs well because of more homogenous, which enhances a larger number of visible veins. Narrower bundles of light do not affect which veins are visible, but they reduce the overexposure at finger boundaries and increase the quality of vascular pattern images. The narrow beam achieves the best performance with 0% of FNMR@FMR0.01%, and the wide beam consistently results in a higher false nonmatch rate. The comparison of left- and right-side illumination has the highest error rates because only the veins in the middle of the finger are visible in both images. Different directional illumination may be interoperable since they produce the same vascular pattern and principally are the projected shadows on the finger surface. Score and image fusion for right- and left-side result in recognition performance similar to that obtained with top illumination, indicating the vein patterns are independent of illumination direction. All results of these experiments support the proposed model.

Robot Grasp Planning: A Learning from Demonstration-Based Approach.

Robot grasping constitutes an essential capability in fulfilling the complexities of advanced industrial operations. This field has been extensively investigated to address a range of practical applications. However, the generation of a stable grasp remains challenging, principally due to the constraints imposed by object geometries and the diverse objectives of the tasks. In this work, we propose a novel learning from demonstration-based grasp-planning framework. This framework is designed to extract crucial human grasp skills, namely the contact region and approach direction, from a single demonstration. Then, it formulates an optimization problem that integrates the extracted skills to generate a stable grasp. Distinct from conventional methods that rely on learning implicit synergies through human demonstration or on mapping the dissimilar kinematics between human hands and robot grippers, our approach focuses on learning the intuitive human intent that involves the potential contact regions and the grasping approach direction. Furthermore, our optimization formulation is capable of identifying the optimal grasp by minimizing the surface fitting error between the demonstrated contact regions on the object and the gripper finger surface and imposing a penalty for any misalignment between the demonstrated and the gripper's approach directions. A series of experiments is conducted to verify the effectiveness of the proposed algorithm through both simulations and real-world scenarios.

Autoencoding a Soft Touch to Learn Grasping from On‐Land to Underwater

Robots play a critical role as the physical agent of human operators in exploring the ocean. However, it remains challenging to grasp objects reliably while fully submerging under a highly pressurized aquatic environment with little visible light, mainly due to the fluidic interference on the tactile mechanics between the finger and object surfaces. This study investigates the transferability of grasping knowledge from on‐land to underwater via a vision‐based soft robotic finger that learns 6D forces and torques (FT) using a supervised variational autoencoder (SVAE). A high‐framerate camera captures the whole‐body deformations while a soft robotic finger interacts with physical objects on‐land and underwater. Results show that the trained SVAE model learns a series of latent representations of the soft mechanics transferable from land to water, presenting a superior adaptation to the changing environments against commercial FT sensors. Soft, delicate, and reactive grasping enabled by tactile intelligence enhances the gripper's underwater interaction with improved reliability and robustness at a much‐reduced cost, paving the path for learning‐based intelligent grasping to support fundamental scientific discoveries in environmental and ocean research.

Design and implementation of shape‐adaptive and multifunctional robotic gripper

AbstractThis paper presents a multifunctional underactuated two fingered adaptive grippers for grasping a wide range of objects in different working scenarios. Two layered‐based novel multifunctional gripper design is proposed by stacking a multijointed closed‐chain mechanism over a multijointed double parallelogram mechanism to achieve a maximum number of grasping techniques. The multijointed closed‐chain mechanism is employed to perform power, shape‐adaptive grasping, and a multijointed double parallelogram mechanism is used to perform scooping, parallel, and pinch grasping. For stable shape‐adaptive/power grasping, the proposed design allows more contact points between the object and the contact surface of fingers as compared to previous gripper mechanisms. Moreover, a complete mathematical model relating the contact forces at the links of each finger to the linear actuation force and spring torque is developed to conduct stability analysis of the proposed gripper design. Finally, simulations and several experiments are performed using real objects in a reconfigurable environment to demonstrate and validate the stable grasping capabilities of the proposed gripper.

Integration of orthogonal Fourier profilometry with blood flow mapping for 3D fingertip biometric authentication

We present herein the combination of Fourier transform profilometry based orthogonal projection with a laser speckle imaging method to provide three-dimensional (3D) fingertip blood flow imaging and shape reconstruction for biometric authentication purposes. In the proposed approach, orthogonal sinusoidal grating patterns with a fixed spatial frequency emanating from a digital projector first illuminate the surface of a person's finger. Then, the projector is blocked and a laser source illuminates the finger. The projector and laser work alternately such that only one source illuminates the finger at a given time allowing no illumination crosstalk between the two devices. The deformed grating patterns and the diffuse backscattered laser light, respectively, are recorded on the same CCD camera. In the computer, the 3D shape of the finger is reconstructed simultaneously with a blood flow map of the finger. Finally, the images are merged yielding a dynamic flow topography visualization of the person's finger. This dual-modality strategy utilizes the strengths of each imaging method in a complementary way, thus enabling simple 3D shape recovery and characterization of a specific user, and increasing the specificity of authentication security. The method is experimentally validated on both human and fake fingers through VanderLugt optical correlation framework. Overall, the results demonstrate the utility of our proposed approach for biometric authentication. We envision that our optoelectronic setup could be potentially integrated into a wide variety security platform.

Ultrasonographic Characteristics in the Fingers and Other Superficial Glomus Tumours.

Glomus tumours are painful superficial tumours, and ultrasonography is an extremely useful and noninvasive diagnostic technique for superficial organs. In this study, we retrospectively examined glomus tumours using ultrasonography. Among 18 patients histopathologically diagnosed with glomus tumours via ultrasonography, we observed five different development sites: subungual areas or those surrounding the nail bed (12), other areas on the finger surface (3), abdominal wall (1), upper arm (1), and forearm (1). The ultrasonographic images revealed significant differences in tumour size, indicating that tumours on other body surfaces tended to be smaller than those on patients' fingers (p < 0.01). The depth/width ratios of tumours on the other body surfaces were significantly higher than those on the fingers (p < 0.05). The tumours showed a regular shape (72.2%) and clear border (100%). Furthermore, most tumours were low-echo tumours with a diameter of up to 15 mm, clear margins, and no lateral shadows. Abundant blood flow and vessels in and out of the tumours were also observed. In conclusion, our study describes the ultrasonographic characteristics of glomus tumours and reveals that they cannot be ruled out when diagnosing small painful subcutaneous tumours.

Research on Receiving Seeds Performance of Belt-Type High-Speed Corn Seed Guiding Device Based on Discrete Element Method

Because the initial speed of the seeds leaving the seed disk is too high, they collide and bounce off the inner wall of the seed guide tube, resulting in poor sowing quality when corn is sown at high speeds above 12 km/h. This study clarifies the primary factors affecting the stability of seed receiving and the accuracy of the seed entering the seed cavity, establishes the dynamic model of seed clamping, transportation, and releasing, and investigates the belt-type high-speed corn seed guiding device with the seed receiving system as the research object. It also proposes an improved method of adding herringbone lines on the finger surface to address this issue. Using EDEM software, a virtual experiment of seed-receiving performance was conducted, and the change trend of stress on seeds with and without a herringbone pattern and different wheel center distance as well as the change trend of the speed of seeds with various feeder wheel speeds and finger length, were both examined. The outcomes of the simulation demonstrate that the herringbone-lined feeder wheel could increase the stress on seeds. The average value of the stress on the seeds is the highest at the wheels’ center distance of 37 mm. The stability and speed fluctuation of seeds introduced into the seed cavity were better when the feeder wheel speed was 560 r/min. The speed of fluctuation and stability of the seeds introduced into the seed cavity were better when the finger length was 12 mm. The high-speed camera test on the test bench was used to verify the seed guiding process in accordance with the simulation results, and the outcomes were largely consistent. The study’s findings can serve as a theoretical foundation for a belt-type high-speed corn seed guiding device optimization test.

Effects of fruit maturities, coatings, and storage temperatures on the qualities and green-life of cavendish banana

Cavendish banana is a climacteric fruit with a fast response to ethylene and a very high respiration rate during storage. Previous studies revealed that these characteristics shortened the green-life and fastened fruit damage, affecting the economic value. Therefore, this study aims to examine the effects of fruit maturity levels, coatings, and storage temperatures on the qualities and green-life of Cavendish banana. The result showed that the level of fruit maturity significantly increased the green-life duration, as well as maintained firmness, diameter loss, acidity, and starch content, but it had no effect on weight loss, oBrix, and glucose. Meanwhile, low temperature was able to delay senescence, promote starch degradation, as well as detain firmness and diameter loss. The results also showed that the combined application of maturity levels + temperatures affected all parameters, while maturities + coatings as well as coatings + storage had effects on firmness, acidity, and starch content. The 1% chitosan coating coverage was analyzed with a Scanning Electron Microscope (SEM), which showed fully covered surface of M1 finger rind tip and some crack points on finger rind base. Furthermore, there was full coverage on M2, and some crack points on M3.

Tissue structure and mechanical properties of the exoskeleton of the huge claws of the mud crab, Scylla serrata

The mud crab, Scylla serrata, has huge claws in comparison with its body size. The color of the claw top’s finger surface changes from white to deep-mottled blue, and this discoloration was strongly associated with the change in hardness inside the finger cross section. With special attention to the discoloration points, the tissue structure of the exoskeleton was investigated via scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction (XRD), and the mechanical properties were examined using Vickers hardness and nanoindentation tests. The exocuticle in the deep blue surface exoskeleton was as thin as that in other crustaceans, and the exoskeleton was occupied by the endocuticle with a twisted plywood structure. On the other hand, in the white surface exoskeleton, the thickness of the hard and dense exocuticle accounted for 52–59% of the exoskeleton thickness. This percentage increased at the claw tip. The hardness of the exocuticle was 2.5 times that of the endocuticle, and the microstructures and mechanical properties gradually varied at the boundary between the exo- and endocuticle. The mechanical properties were almost constant in the exocuticle, but calcium (Ca) concentrations decreased from the outer surface toward the boundary in that region and magnesium (Mg) concentrations increased. The change in the unit cell volume obtained via XRD suggested that some of the Ca atoms in the calcite crystal structure in that region were replaced with Mg atoms. Changes in crustacean coloration may help us to understand the tissue structure and mechanical properties within the exoskeleton.Graphical

Giant Cell Tumor of FDP Tendon Sheath in Young: A Rare Case Report

Introduction: Giant cell tumor of the tendon sheath of the hand (GCTTS) is a benign tumor of unknown cause. The clinical diagnosis is supported by pre-operative imaging. The standard of care is surgical resection along with histological confirmation. It appears as a palpable enlargement that is painless. Although pre-operative imaging and fine-needle aspiration cytology (FNAC) corroborate its suspicion, histology following surgical resection is mostly responsible for establishing its diagnosis. Due to its rarity, a case of GCT of the flexor tendon sheath of the right index finger is reported here. Case Report: We give an example of a patient with giant cell tumor (GCT) of the flexor digitorum profundus tendon sheath in a male patient who is 18 years old. On examination, a 1.8 × 1.2 × 1.0 cm swelling was seen covering an adjoining tendon on the palmar surface of the right index finger at the middle phalanx. The swelling was well-defined, had a smooth surface, was consistently firm, and could be easily pushed in a sideways direction. An isolated soft-tissue shadow was visible in the affected area of the hand’s X-ray, but there was no bone involvement. As a professional shooter, the patient utilizes his right index finger as a trigger finger. Conclusion: In adults with hand soft-tissue tumors, GCTTS should be considered as a possible differential diagnosis, especially when there’s any evidence of repeated inconsequential minor trauma. The patient should be monitored to find and treat recurrences. Keywords: Giant-cell tumors, FDP tendon, GCTTS.

Prosthetic finger for fingertip tactile sensing via flexible chromatic optical waveguides.

Building prosthetics indistinguishable from human limbs to accurately receive and transmit sensory information to users not only promises to radically improve the lives of amputees, but also shows potential in a range of robotic applications. Currently, a mainstream approach is to embed electrical or optical sensors with force/thermal sensing functions on the surface or inside of prosthetic fingers. Compared with electrical sensing technologies, tactile sensors based on stretchable optical waveguides have the advantages of easy fabrication, chemical safety, environmental stability, and compatibility with prosthetic structural materials. However, so far, research has mainly focused on the perception of finger joint motion or external press, and there is still a lack of study on optical sensors with fingertip tactile capabilities (such as texture, hardness, slip detection, etc.). Here we report a 3D printing prosthetic finger with flexible chromatic optical waveguides implanted at the fingertip. The finger achieves distributed displacement/force sensing detection, and exhibits high sensitivity, fast response and good stability. The finger can be used to conduct active sensory experiments, and the detection parameters include object contour, hardness, slip direction and speed, temperature, etc. Finally, exploratory research on identifying and manipulating objects is carried out with this finger. The developed prosthetic finger can artificially recreate touch perception and realize complex functions such as note-writing analysis and braille recognition.

Comparative study of rose and hibiscus petals powders in latent friction ridge analysis

Fingerprints are the friction ridges found on the fingers and palm of hands. These prints are considered the most valuable evidence in the court of law as these ridges provide uniqueness to every individual. Powder dusting is one of the prevalent approaches to developing fingerprints on various surfaces. This involves the application of finely formulated powders on the fingermark impression using a camel hair brush. in this article, we have used organic household waste materials like rose and hibiscus petals for developing the powders used in latent fingerprints development. The particle of powder gets adhered to sweat and moisture deposited on the surface of fingers, palm, and sole, which provide effective visualization and give the fingerprint details (minutiae). Finally, the formulation of the powder sticks to the ridges, and the excess powder is blown away. The powder is multicolored in this case, the patterns are apparent, resulting in an exceptional outcome. The objective of the study is to provide a replacement to the conventional, expensive and toxic laboratory powders. These organic powders are easily available, eco-friendly, cost-effective and non-toxic approach for latent fingerprint development and is a reliable technique to use at crime scene and future use.

Effect of Charged-cluster Distribution of the ZIF268 Zinc Finger Surface on Cell Membrane Permeability

To investigate the importance of charged-cluster distribution in cell permeability, ZIF268 zinc finger (ZF) was examined as a new target protein. We found that in addition to the total number of cationic charges, the surface distribution of cationic and anionic clusters has a significant impact on intracellular transport. These findings may be useful for predicting other ZFs with high membrane permeability based on the distribution of charged clusters and for redesigning natural ZFs to create artificial proteins with efficient membrane permeability.

Design, modeling, and characteristic analysis of an index finger exoskeleton for rehabilitation

Since the rehabilitation hand exoskeleton robot is the current research hotspot, it can play a great role in patients’ hand rehabilitation and can replace the rehabilitation physician to treat the patient. Many of today’s rehabilitation hand exoskeleton robots can not achieve a good rehabilitation effect. In order to improve the treatment effect of the rehabilitation hand exoskeleton robot on patients and alleviate the pressure of insufficient human hands in China’s rehabilitation physicians, this paper, on the basis of analyzing the biological characteristics of the human hand, focuses on the functional analysis of the rehabilitation exoskeleton hand, the mechanical structure design of the exoskeleton hand, Kinematic analysis, Modeling and simulation to design an exoskeleton hand using a one-wheel-two way combining sliding guide rod and SEA tandem elastic drive to achieve the mechanism that can adjust the stretch according to the length of the finger and the rehabilitation force perpendicular for the purpose of the finger surface. A closed-loop structure is established to analyze the mechanism of plane motion of the structure and the coupling of the structure and the range of motion of the human hand. Through simulation analysis of the motion trajectory of the structure and the stability of the dynamic model analysis system based on the force source control method to establish a dynamic model of the tandem elastic drive, the results show that the DIP joint rotation angle is 16-73 degrees, the PIP joint rotation angle is 0-108 degrees, and the MP joint is 0-86 degrees, which is basically consistent with the human hand, and the series elastic drive should choose a smaller stiffness and larger damping to ensure the stability of the system.

Design and Experimental Research of Robot Finger Sliding Tactile Sensor Based on FBG.

Aiming at the problem of flexible sliding tactile sensing for the actual grasp of intelligent robot fingers, a double-layer sliding tactile sensor based on fiber Bragg grating (FBG) for robot fingers is proposed in this paper. Firstly, the optimal embedding depth range of FBG in the elastic matrix of polydimethylsiloxane (PDMS) was determined through finite element analysis and static detection experiments of finger tactile sensing. Secondly, the sensor structure is optimized and designed through the simulation and dynamic experiments of sliding sensing to determine the final array structure. Thirdly, the sensing array is actually pasted on the surface of the robot finger and the sensing characteristics testing platform is built to test and analyze the basic performance of the sliding tactile sensor. Then, the sensor array is actually attached to the finger surface of the robot and the sensing characteristics testing platform is built to experiment and analyze the basic performance of the sliding tactile sensor. Finally, a sliding tactile sensing experiment of robot finger grasping is conducted. The experimental results show that the sliding tactile sensor designed in this paper has good repeatability and creep resistance, with sensitivities of 12.4 pm/N, 11.6 pm/N, and 14.5 pm/N, respectively, and the overall deviation is controlled within 5 pm. Meanwhile, it can effectively sense the signals of the robot fingers during static contact and sliding. The sensor has a high degree of fit with the robot finger structure, and has certain application value for the perception of sliding tactile signals in the object grasping of intelligent robot objects.