AIM:To evaluate the safety and efficacy of scleral-fixated 3-looped haptics intraocular lens(IOL)implantation for surgical management of microspherophakia.METHODS:A retrospective case series include 10 microspherophak...AIM:To evaluate the safety and efficacy of scleral-fixated 3-looped haptics intraocular lens(IOL)implantation for surgical management of microspherophakia.METHODS:A retrospective case series include 10 microspherophakic patients(15 eyes)who underwent lens removal plus a modified surgical treatment of scleral-fixated 3-looped haptics IOL implantation.The primary outcomes involved visual acuity,intraocular pressure(IOP).Secondary outcomes were spherical equivalent(SE),anterior chamber depth(ACD),corneal endothelial cell density and postoperative complications.RESULTS:After a postoperative follow-up of 17.60±15.44mo,improved visual outcomes can be observed.The uncorrected distance visual acuity(UCVA)log MAR improved from 1.54±0.59 preoperatively to 0.51±0.35 postoperatively(P=0.001),and best corrected visual acuity(BCVA)log MAR improved from 0.97±0.91 preoperatively to 0.24±0.23 postoperatively(P=0.003).Moreover,the SE decreased from-9.58±7.47D preoperatively to-0.65±2.21 D postoperatively(P<0.001).In terms of safety profile,the average IOP decreased from 21.10±12.94 mm Hg preoperatively to 14.03±3.57 mm Hg postoperatively(P=0.044),and the previously elevated IOP of three eyes decreased to the normal range.The ACD increased from 2.25±1.45 mm preoperatively to 3.35±0.39 mm postoperatively(P=0.017).The density of corneal endothelial cells did not change significantly after surgery(P=0.140).The posterior chamber IOLs were well centered and no severe complications were found.CONCLUSION:Lens removal plus the modified surgical treatment of scleral-fixated 3-looped haptics IOL implantation can help in improvement of visual acuity,which can be regarded as a relative safe method for the surgical management of microspherophakia.展开更多
In this paper, we handle collaborative work in which two users move an object together to eliminate a target in a 3-D virtual space. In the work, the users transmit their wills about movement direction of the object t...In this paper, we handle collaborative work in which two users move an object together to eliminate a target in a 3-D virtual space. In the work, the users transmit their wills about movement direction of the object to each other by only haptics and by haptics and vision (including with/ without drawing an arrow to indicate the direction of force applied to the object by the other user). We carry out QoE (Quality of Experience) assessment subjectively and objectively to investigate the influence of network delay on will transmission. As a result, we clarify the effects of vision on the transmissibility of haptic will transmission.展开更多
Due to the inherent shortcomings of the hardware,the immersion of visual interaction between the user and the virtual reality(VR)equipment is greatly reduced.In this paper,effects of eye-around vibration haptics on im...Due to the inherent shortcomings of the hardware,the immersion of visual interaction between the user and the virtual reality(VR)equipment is greatly reduced.In this paper,effects of eye-around vibration haptics on improving the VR immersion were studied.The vibration was generated by flexible vibrators whose performance was evaluated by a laser vibrometer.Fitting the vibrators on the human eye area at different positions and derived by different waveforms and frequencies of the input signal,the effects of vibration on the human vision and comfort of the users were verified.Then,with the selected input signals and fitting locations,different kinds of vibration were applied on the eye area cooperating with virtual reality images or videos to evaluate the changes of immersion.Research results provide references to the modeling of eye tactile feedback and the design of relevant tactile device in improving the VR immersion.展开更多
Background: In order to develop new and better laparoscopic bowel instruments, which reduces patient risks, the opinions and experience that surgeons have with current laparoscopic bowel grasper haptics is important. ...Background: In order to develop new and better laparoscopic bowel instruments, which reduces patient risks, the opinions and experience that surgeons have with current laparoscopic bowel grasper haptics is important. In this study we explored this by means of a questionnaire. Method: A total of 386 online- questionnaires, were sent to laparoscopic surgeons working in European hospitals. They were all members of the European Association of Endoscopic Surgery and perform laparoscopic obesities or bowel surgery. Surgeons where divided into different age and experience groups. Results: A total of 174 completely filled out forms were analyzed. In total, 16% of the surgeons cannot prevent damage when they pinch too hard, although they (10%) might have seen or felt it. Seven percent of the respondents were not able to see or feel tissue slippage. Whereas 31% can see or feel slippage they cannot do anything to prevent it. Overall, most of the respondents would appreciate technical changes in the laparoscopic bowel graspers to reduce tissue damage. Of all the respondents, 79% maintain that it is necessary to have a new laparoscopic grasper with augmented feedback. The majority of the respondents (77%) would like to have tactile feedback as an indication of the level of pinch force. There are not many differences in the opinions of surgeons at different skill levels. Conclusion: From the results of the questionnaire and the other comments made by respondents it is evident that research and developments in the field of new laparoscopic graspers should continue.展开更多
Background In virtual environments(VEs),users can explore a large virtual scene through the viewpoint operation of a head-mounted display(HMD)and movement gains combined with redirected walking technology.The existing...Background In virtual environments(VEs),users can explore a large virtual scene through the viewpoint operation of a head-mounted display(HMD)and movement gains combined with redirected walking technology.The existing redirection methods and viewpoint operations are effective in the horizontal direction;however,they cannot help participants experience immersion in the vertical direction.To improve the immersion of upslope walking,this study presents a virtual climbing system based on passive haptics.Methods This virtual climbing system uses the tactile feedback provided by sponges,a commonly used flexible material,to simulate the tactile sense of a user's soles.In addition,the visual stimulus of the HMD,the tactile feedback of the flexible material,and the operation of the user's walking in a VE combined with redirection technology are all adopted to enhance the user's perception in a VE.In the experiments,a physical space with a hard-flat floor and three types of sponges with thicknesses of 3,5,and 8cm were utilized.Results We recruited 40 volunteers to conduct these experiments,and the results showed that a thicker flexible material increases the difficulty for users to roam and walk within a certain range.Conclusion The virtual climbing system can enhance users'perception of upslope walking in a VE.展开更多
High-fidelity tactile rendering offers significant potential for improving the richness and immersion of touchscreen interactions.This study focuses on a quantitative description of tactile rendering fidelity using a ...High-fidelity tactile rendering offers significant potential for improving the richness and immersion of touchscreen interactions.This study focuses on a quantitative description of tactile rendering fidelity using a custom-designed hybrid electrovibration and mechanical vibration(HEM)device.An electrovibration and mechanical vibration(EMV)algorithm that renders 3D gratings with different physical heights was proposed and shown to achieve 81%accuracy in shape recognition.Models of tactile rendering fidelity were established based on the evaluation of the height discrimination threshold,and the psychophysical-physical relationships between the discrimination and reference heights were well described by a modification of Weber’s law,with correlation coefficients higher than 0.9.The physiological-physical relationship between the pulse firing rate and the physical stimulation voltage was modeled using the Izhikevich spiking model with a logarithmic relationship.展开更多
This research paper introduces a soft VR glove that enhances how users interact with virtual objects. It seamlessly integrates discrete modules for sensing and providing haptic feedback, encompassing tactile and kinae...This research paper introduces a soft VR glove that enhances how users interact with virtual objects. It seamlessly integrates discrete modules for sensing and providing haptic feedback, encompassing tactile and kinaesthetic aspects while prioritizing wearability and natural finger movements. The glove employs custom-designed flexible bend sensors with carbon-impregnated film for in-situ joint angle tracking, simplifying the sensing system and enhancing portability. A multi-modal haptic feedback approach includes an innovative pneumatically actuated tactile feedback technique and a motor-tendon-driven kinaesthetic feedback system, providing exceptional realism in virtual object manipulation. The glove’s kinaesthetic feedback lets users perceive virtual objects’ size, shape, and stiffness characteristics. Psychophysical investigations demonstrate how readily the users acclimate to this hardware and prove each module’s effectiveness and synergistic operation. This soft VR glove represents a minimalist, lightweight, and comprehensive solution for authentic haptic interaction in virtual environments, opening new possibilities for applications in various fields.展开更多
This letter provides a concise review of the pertinent literature on visual and tactile hallucinations in elderly patients.The discussion addresses differential diagnoses and potential underlying mechanisms,as well as...This letter provides a concise review of the pertinent literature on visual and tactile hallucinations in elderly patients.The discussion addresses differential diagnoses and potential underlying mechanisms,as well as the psychopathology associated with tactile hallucinations,and emphasizes the necessity for invest-igation into the possibility of coexisting delusional infestation(parasitosis).These symptoms frequently manifest in patients with primary psychotic disorders,organic mental disorders,and substance use disorders.The proposed pathophy-siological mechanisms may involve dopaminergic imbalances and dysfunction of the striatal dopamine transporter.展开更多
Microrobots powered by an external magnetic field could be used for sophisticated medical applications such as cell treatment,micromanipulation,and noninvasive surgery inside the body.Untethered microrobot application...Microrobots powered by an external magnetic field could be used for sophisticated medical applications such as cell treatment,micromanipulation,and noninvasive surgery inside the body.Untethered microrobot applications can benefit from haptic technology and telecommunication,enabling telemedical micro-manipulation.Users can manipulate the microrobots with haptic feedback by interacting with the robot operating system remotely in such applications.Artificially created haptic forces based on wirelessly transmitted data and model-based guidance can aid human operators with haptic sensations while manipulating microrobots.The system presented here includes a haptic device and a magnetic tweezer system linked together using a network-based teleoperation method with motion models in fluids.The magnetic microrobots can be controlled remotely,and the haptic interactions with the remote environment can be felt in real time.A time-domain passivity controller is applied to overcome network delay and ensure stability of communication.This study develops and tests a motion model for microrobots and evaluates two image-based 3D tracking algorithms to improve tracking accuracy in various Newtonian fluids.Additionally,it demonstrates that microrobots can group together to transport multiple larger objects,move through microfluidic channels for detailed tasks,and use a novel method for disassembly,greatly expanding their range of use in microscale operations.Remote medical treatment in multiple locations,remote delivery of medication without the need for physical penetration of the skin,and remotely controlled cell manipulations are some of the possible uses of the proposed technology.展开更多
In the realm of virtual reality(VR),haptic feedback is integral to enhance the immersive experience;yet,existing wearable devices predominantly rely on skin contact feedback,lacking options for compact and non-contact...In the realm of virtual reality(VR),haptic feedback is integral to enhance the immersive experience;yet,existing wearable devices predominantly rely on skin contact feedback,lacking options for compact and non-contact breeze-sense feedback.Herein,we propose a compact and non-contact working model piezoelectret actuator for providing a gentle and safe breeze sensation.This easy-fabricated and flexible breeze-sense generator with thickness around 1 mm generates air flow pressure up to~163 Pa,which is significantly sensed by human skin.In a typical demonstration,the breeze-sense generators array showcases its versatility by employing multiple coded modes for non-contact information transmitting.The thin thinness and good flexibility facilitate seamless integration with wearable VR setups,and the wearable arrays empower volunteers to precisely perceive the continuous and sudden breeze senses in the virtual environments.This work is expected to inspire developing new haptic feedback devices that play pivotal roles in human-machine interfaces for VR applications.展开更多
IntuiGrasp is a novel three-fingered dexterous hand that pioneers bio-inspired demonstrations with intuitive priors(BDIP)to bridge the gap between human tactile intuition and robotic execution.Unlike conven-tional pro...IntuiGrasp is a novel three-fingered dexterous hand that pioneers bio-inspired demonstrations with intuitive priors(BDIP)to bridge the gap between human tactile intuition and robotic execution.Unlike conven-tional programming,BDIP leverages human's innate priors(e.g.,“A pack of tissues requires gentle grasps,cups demand firm contact”)by enabling real-time transfer of gesture and force policies during physical demon-stration.When a human demonstrator wears IntuiGrasp,driven rings provide real-time haptic feedback on contact stress and slip,while inte-grated tactile sensors translate these human policies into image data,offering valuable data for imitation learning.In this study,human teachers use IntuiGrasp to demonstrate how to grasp three types of objects:a cup,a crumpled tissue pack,and a thin playing card.IntuiGrasp translates the policies for grasping these objects into image information that describes tactile sensations in real time.展开更多
Background Haptic feedback plays a crucial role in virtual reality(VR)interaction,helping to improve the precision of user operation and enhancing the immersion of the user experience.Instrumental haptic feedback in v...Background Haptic feedback plays a crucial role in virtual reality(VR)interaction,helping to improve the precision of user operation and enhancing the immersion of the user experience.Instrumental haptic feedback in virtual environments is primarily realized using grounded force or vibration feedback devices.However,improvements are required in terms of the active space and feedback realism.Methods We propose a lightweight and flexible haptic feedback glove that can haptically render objects in VR environments via kinesthetic and vibration feedback,thereby enabling users to enjoy a rich virtual piano-playing experience.The kinesthetic feedback of the glove relies on a cable-pulling mechanism that rotates the mechanism and pulls the two cables connected to it,thereby changing the amount of force generated to simulate the hardness or softness of the object.Vibration feedback is provided by small vibration motors embedded in the bottom of the fingertips of the glove.We designed a piano-playing scenario in the virtual environment and conducted user tests.The evaluation metrics were clarity,realism,enjoyment,and satisfaction.Results A total of 14 subjects participated in the test,and the results showed that our proposed glove scored significantly higher on the four evaluation metrics than the nofeedback and vibration feedback methods.Conclusions Our proposed glove significantly enhances the user experience when interacting with virtual objects.展开更多
Immersion, interaction, and imagination are three features of virtual reality (VR). Existing VR systems possess fairly realistic visual and auditory feedbacks, and however, are poor with haptic feedback, by means of w...Immersion, interaction, and imagination are three features of virtual reality (VR). Existing VR systems possess fairly realistic visual and auditory feedbacks, and however, are poor with haptic feedback, by means of which human can perceive the physical world via abundant haptic properties. Haptic display is an interface aiming to enable bilateral signal communications between human and computer, and thus to greatly enhance the immersion and interaction of VR systems. This paper surveys the paradigm shift of haptic display occurred in the past 30 years, which is classified into three stages, including desktop haptics, surface haptics, and wearable haptics. The driving forces, key technologies and typical applications in each stage are critically reviewed. Toward the future high-fidelity VR interaction, research challenges are highlighted concerning handheld haptic device, multimodal haptic device, and high fidelity haptic rendering. In the end, the importance of understanding human haptic perception for designing effective haptic devices is addressed.展开更多
BACKGROUND Perception is frequently impaired in patients with Alzheimer’s disease(AD).Several patients exhibit visual or haptic hallucinations.CASE SUMMARY A 71-year-old Chinese man presented with visual and haptic h...BACKGROUND Perception is frequently impaired in patients with Alzheimer’s disease(AD).Several patients exhibit visual or haptic hallucinations.CASE SUMMARY A 71-year-old Chinese man presented with visual and haptic hallucinations he had been experiencing for 2 weeks.The clinical manifestations were the feeling of insects crawling and biting the limbs and geison.He looked for the insects while itching and scratching,which led to skin breakage on the limbs.He was treated with topical and anti-allergic drugs in several dermatology departments without any significant improvement.After admission,the patient was administered risperidone(0.5 mg)and duloxetine(2 mg/day).One week later,the dose of risperidone was increased to 2 mg/day,and that of duloxetine was increased to 60 mg/day.After 2 weeks of treatment,the patient’s sensation of insects crawling and biting disappeared,and his mood stabilized.CONCLUSION This patient manifested psychiatric behavioral symptoms caused by AD brain atrophy.It was important to re-evaluate the patient’s cognitive-psychological status when the patient repeatedly went to the hospital for treatment.Follow-up attention to cognitive function and the consideration of perceptual deficits as early manifestations of AD should be considered.展开更多
Haptic is the modality that complements traditional multimedia,i.e.,audiovisual,to evolve the next wave of innovation at which the Internet data stream can be exchanged to enable remote skills and control applications...Haptic is the modality that complements traditional multimedia,i.e.,audiovisual,to evolve the next wave of innovation at which the Internet data stream can be exchanged to enable remote skills and control applications.This will require ultra-low latency and ultra-high reliability to evolve the mobile experience into the era of Digital Twin and Tactile Internet.While the 5th generation of mobile networks is not yet widely deployed,Long-Term Evolution(LTE-A)latency remains much higher than the 1 ms requirement for the Tactile Internet and therefore the Digital Twin.This work investigates an interesting solution based on the incorporation of Software-defined networking(SDN)and Multi-access Mobile Edge Computing(MEC)technologies in an LTE-A network,to deliver future multimedia applications over the Tactile Internet while overcoming the QoS challenges.Several network scenarios were designed and simulated using Riverbed modeler and the performance was evaluated using several time-related Key Performance Indicators(KPIs)such as throughput,End-2-End(E2E)delay,and jitter.The best scenario possible is clearly the one integrating MEC and SDN approaches,where the overall delay,jitter,and throughput for haptics-attained 2 ms,0.01 ms,and 1000 packets per second.The results obtained give clear evidence that the integration of,both SDN and MEC,in LTE-A indicates performance improvement,and fulfills the standard requirements in terms of the above KPIs,for realizing a Digital Twin/Tactile Internet-based system.展开更多
The utilization of high-resolution haptic feedback devices in a virtual reality(VR)environment can increase the precision of controlling remotely operated vehicles and reduce training costs for subsea construction ope...The utilization of high-resolution haptic feedback devices in a virtual reality(VR)environment can increase the precision of controlling remotely operated vehicles and reduce training costs for subsea construction operations.This paper introduces a novel flexible-driven wearable pin-array device.The spatial separation of the control box and actuator allows the device to attain natural and seamless interactive movements while delivering high-density haptic feedback in VR.The pin array consists of 25 haptic pin modules that run on a linear servo motor via a flexible shaft for force transmission.The analysis and calculation of the flexible transmission resistance effect using the haptic pin module's shaft length and bending radius were conducted.A series of experiments was performed to gather comprehensive data on the pin module's output,transmission resistance and error,and response delay to optimize its structural design and transmission strategy.The device's effectiveness in rendering shape and coarse texture was evaluated via two user studies.The results affirm that the introduced device enables users to precisely discern seven shapes and four distinct coarse surfaces.展开更多
Haptic communications is recognized as a promising enabler of extensive services by enabling real-time haptic control and feedback in remote environments,e.g.,teleoperation and autonomous driving.Considering the stric...Haptic communications is recognized as a promising enabler of extensive services by enabling real-time haptic control and feedback in remote environments,e.g.,teleoperation and autonomous driving.Considering the strict transmission requirements on reliability and latency,Device-to-Device(D2D)communications is introduced to assist haptic communications.In particular,the teleoperators with poor channel quality are assisted by auxiliaries,and each auxiliary and its corresponding teleoperator constitute a D2D pair.However,the haptic interaction and the scarcity of radio resources pose severe challenges to the resource allocation,especially facing the sporadic packet arrivals.First,the contentionbased access scheme is applied to achieve low-latency transmission,where the resource scheduling latency is omitted and users can directly access available resources.In this context,we derive the reliability index of D2D pairs under the contention-based access scheme,i.e.,closed-loop packet error probability.Then,the reliability performance is guaranteed by bidirectional power control,which aims to minimize the sum packet error probability of all D2D pairs.Potential game theory is introduced to solve the problem with low complexity.Accordingly,a distributed power control algorithm based on synchronous log-linear learning is proposed to converge to the optimal Nash Equilibrium.Experimental results demonstrate the superiority of the proposed learning algorithm.展开更多
Background The sense of touch plays a crucial role in interactive behavior within virtual spaces,particularly when visual attention is absent.Although haptic feedback has been widely used to compensate for the lack of...Background The sense of touch plays a crucial role in interactive behavior within virtual spaces,particularly when visual attention is absent.Although haptic feedback has been widely used to compensate for the lack of visual cues,the use of tactile information as a predictive feedforward cue to guide hand movements remains unexplored and lacks theoretical understanding.Methods This study introduces a fingertip aero-haptic rendering method to investigate its effectiveness in directing hand movements during eyes-free spatial interactions.The wearable device incorporates a multichannel micro-airflow chamber to deliver adjustable tactile effects on the fingertips.Results The first study verified that tactile directional feedforward cues significantly improve user capabilities in eyes-free target acquisition and that users rely heavily on haptic indications rather than spatial memory to control their hands.A subsequent study examined the impact of enriched tactile feedforward cues on assisting users in determining precise target positions during eyes-free interactions,and assessed the required learning efforts.Conclusions The haptic feedforward effect holds great practical promise in eyeless design for virtual reality.We aim to integrate cognitive models and tactile feedforward cues in the future,and apply richer tactile feedforward information to alleviate users'perceptual deficiencies.展开更多
Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the body.For some time,efforts have been made to improve surgical pre training thro...Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the body.For some time,efforts have been made to improve surgical pre training through practical exercises on abstracted and reduced models.Methods The authors strive for a portable,easy to use and cost-effective Virtual Reality-based(VR)laparoscopic pre-training platform and therefore address the question of how such a system has to be designed to achieve the quality of today's gold standard using real tissue specimens.Current VR controllers are limited regarding haptic feedback.Since haptic feedback is necessary or at least beneficial for laparoscopic surgery training,the platform to be developed consists of a newly designed prototype laparoscopic VR controller with haptic feedback,a commercially available head-mounted display,a VR environment for simulating a laparoscopic surgery,and a training concept.Results To take full advantage of benefits such as repeatability and cost-effectiveness of VR-based training,the system shall not require a tissue sample for haptic feedback.It is currently calculated and visually displayed to the user in the VR environment.On the prototype controller,a first axis was provided with perceptible feedback for test purposes.Two of the prototype VR controllers can be combined to simulate a typical both-handed use case,e.g.,laparoscopic suturing.A Unity based VR prototype allows the execution of simple standard pre-trainings.Conclusions The first prototype enables full operation of a virtual laparoscopic instrument in VR.In addition,the simulation can compute simple interaction forces.Major challenges lie in a realistic real-time tissue simulation and calculation of forces for the haptic feedback.Mechanical weaknesses were identified in the first hardware prototype,which will be improved in subsequent versions.All degrees of freedom of the controller are to be provided with haptic feedback.To make forces tangible in the simulation,characteristic values need to be determined using real tissue samples.The system has yet to be validated by cross-comparing real and VR haptics with surgeons.展开更多
An increasing number of studies have focused on providing rich tactile feedback in virtual reality interactive scenarios.In this study,we addressed a tapping scenario in virtual reality by designing MatStick,a solutio...An increasing number of studies have focused on providing rich tactile feedback in virtual reality interactive scenarios.In this study,we addressed a tapping scenario in virtual reality by designing MatStick,a solution capable of offering diverse tapping sensations.MatStick utilizes a soft physical base to provide force feedback and modulates the instantaneous vibration of the base using a voice coil motor,thereby altering the perception of the base material.We conducted two psychophysical experiments and a subjective evaluation to assess the capabilities of MatStick.The results demonstrate that MatStick can deliver rich tapping sensations.Although users may find it challenging to directly correlate the tapping sensation with the actual physical material based solely on tactile feedback,in immersive scenarios combined with visual and auditory cues,MatStick significantly enhances the user's interaction experience.展开更多
文摘AIM:To evaluate the safety and efficacy of scleral-fixated 3-looped haptics intraocular lens(IOL)implantation for surgical management of microspherophakia.METHODS:A retrospective case series include 10 microspherophakic patients(15 eyes)who underwent lens removal plus a modified surgical treatment of scleral-fixated 3-looped haptics IOL implantation.The primary outcomes involved visual acuity,intraocular pressure(IOP).Secondary outcomes were spherical equivalent(SE),anterior chamber depth(ACD),corneal endothelial cell density and postoperative complications.RESULTS:After a postoperative follow-up of 17.60±15.44mo,improved visual outcomes can be observed.The uncorrected distance visual acuity(UCVA)log MAR improved from 1.54±0.59 preoperatively to 0.51±0.35 postoperatively(P=0.001),and best corrected visual acuity(BCVA)log MAR improved from 0.97±0.91 preoperatively to 0.24±0.23 postoperatively(P=0.003).Moreover,the SE decreased from-9.58±7.47D preoperatively to-0.65±2.21 D postoperatively(P<0.001).In terms of safety profile,the average IOP decreased from 21.10±12.94 mm Hg preoperatively to 14.03±3.57 mm Hg postoperatively(P=0.044),and the previously elevated IOP of three eyes decreased to the normal range.The ACD increased from 2.25±1.45 mm preoperatively to 3.35±0.39 mm postoperatively(P=0.017).The density of corneal endothelial cells did not change significantly after surgery(P=0.140).The posterior chamber IOLs were well centered and no severe complications were found.CONCLUSION:Lens removal plus the modified surgical treatment of scleral-fixated 3-looped haptics IOL implantation can help in improvement of visual acuity,which can be regarded as a relative safe method for the surgical management of microspherophakia.
文摘In this paper, we handle collaborative work in which two users move an object together to eliminate a target in a 3-D virtual space. In the work, the users transmit their wills about movement direction of the object to each other by only haptics and by haptics and vision (including with/ without drawing an arrow to indicate the direction of force applied to the object by the other user). We carry out QoE (Quality of Experience) assessment subjectively and objectively to investigate the influence of network delay on will transmission. As a result, we clarify the effects of vision on the transmissibility of haptic will transmission.
基金Supported by Knowledge Innovation Program of Shenzhen City(JCYJ20170306141926192)Guiding Project of Industrial Technology Development and Application(2019H0004).
文摘Due to the inherent shortcomings of the hardware,the immersion of visual interaction between the user and the virtual reality(VR)equipment is greatly reduced.In this paper,effects of eye-around vibration haptics on improving the VR immersion were studied.The vibration was generated by flexible vibrators whose performance was evaluated by a laser vibrometer.Fitting the vibrators on the human eye area at different positions and derived by different waveforms and frequencies of the input signal,the effects of vibration on the human vision and comfort of the users were verified.Then,with the selected input signals and fitting locations,different kinds of vibration were applied on the eye area cooperating with virtual reality images or videos to evaluate the changes of immersion.Research results provide references to the modeling of eye tactile feedback and the design of relevant tactile device in improving the VR immersion.
文摘Background: In order to develop new and better laparoscopic bowel instruments, which reduces patient risks, the opinions and experience that surgeons have with current laparoscopic bowel grasper haptics is important. In this study we explored this by means of a questionnaire. Method: A total of 386 online- questionnaires, were sent to laparoscopic surgeons working in European hospitals. They were all members of the European Association of Endoscopic Surgery and perform laparoscopic obesities or bowel surgery. Surgeons where divided into different age and experience groups. Results: A total of 174 completely filled out forms were analyzed. In total, 16% of the surgeons cannot prevent damage when they pinch too hard, although they (10%) might have seen or felt it. Seven percent of the respondents were not able to see or feel tissue slippage. Whereas 31% can see or feel slippage they cannot do anything to prevent it. Overall, most of the respondents would appreciate technical changes in the laparoscopic bowel graspers to reduce tissue damage. Of all the respondents, 79% maintain that it is necessary to have a new laparoscopic grasper with augmented feedback. The majority of the respondents (77%) would like to have tactile feedback as an indication of the level of pinch force. There are not many differences in the opinions of surgeons at different skill levels. Conclusion: From the results of the questionnaire and the other comments made by respondents it is evident that research and developments in the field of new laparoscopic graspers should continue.
基金the National Key R&D Program of China(2018YFB1404100)National Natural Science Foundation of China(62072405)Zhejiang Provincial Natural Science Foundation of China(LGF20F020017).
文摘Background In virtual environments(VEs),users can explore a large virtual scene through the viewpoint operation of a head-mounted display(HMD)and movement gains combined with redirected walking technology.The existing redirection methods and viewpoint operations are effective in the horizontal direction;however,they cannot help participants experience immersion in the vertical direction.To improve the immersion of upslope walking,this study presents a virtual climbing system based on passive haptics.Methods This virtual climbing system uses the tactile feedback provided by sponges,a commonly used flexible material,to simulate the tactile sense of a user's soles.In addition,the visual stimulus of the HMD,the tactile feedback of the flexible material,and the operation of the user's walking in a VE combined with redirection technology are all adopted to enhance the user's perception in a VE.In the experiments,a physical space with a hard-flat floor and three types of sponges with thicknesses of 3,5,and 8cm were utilized.Results We recruited 40 volunteers to conduct these experiments,and the results showed that a thicker flexible material increases the difficulty for users to roam and walk within a certain range.Conclusion The virtual climbing system can enhance users'perception of upslope walking in a VE.
基金Supported by the National Natural Science Foundation of China under Grants 61631010 and 61806085.
文摘High-fidelity tactile rendering offers significant potential for improving the richness and immersion of touchscreen interactions.This study focuses on a quantitative description of tactile rendering fidelity using a custom-designed hybrid electrovibration and mechanical vibration(HEM)device.An electrovibration and mechanical vibration(EMV)algorithm that renders 3D gratings with different physical heights was proposed and shown to achieve 81%accuracy in shape recognition.Models of tactile rendering fidelity were established based on the evaluation of the height discrimination threshold,and the psychophysical-physical relationships between the discrimination and reference heights were well described by a modification of Weber’s law,with correlation coefficients higher than 0.9.The physiological-physical relationship between the pulse firing rate and the physical stimulation voltage was modeled using the Izhikevich spiking model with a logarithmic relationship.
基金CSIR research grant HCP-26 supported the work reported in this article.
文摘This research paper introduces a soft VR glove that enhances how users interact with virtual objects. It seamlessly integrates discrete modules for sensing and providing haptic feedback, encompassing tactile and kinaesthetic aspects while prioritizing wearability and natural finger movements. The glove employs custom-designed flexible bend sensors with carbon-impregnated film for in-situ joint angle tracking, simplifying the sensing system and enhancing portability. A multi-modal haptic feedback approach includes an innovative pneumatically actuated tactile feedback technique and a motor-tendon-driven kinaesthetic feedback system, providing exceptional realism in virtual object manipulation. The glove’s kinaesthetic feedback lets users perceive virtual objects’ size, shape, and stiffness characteristics. Psychophysical investigations demonstrate how readily the users acclimate to this hardware and prove each module’s effectiveness and synergistic operation. This soft VR glove represents a minimalist, lightweight, and comprehensive solution for authentic haptic interaction in virtual environments, opening new possibilities for applications in various fields.
文摘This letter provides a concise review of the pertinent literature on visual and tactile hallucinations in elderly patients.The discussion addresses differential diagnoses and potential underlying mechanisms,as well as the psychopathology associated with tactile hallucinations,and emphasizes the necessity for invest-igation into the possibility of coexisting delusional infestation(parasitosis).These symptoms frequently manifest in patients with primary psychotic disorders,organic mental disorders,and substance use disorders.The proposed pathophy-siological mechanisms may involve dopaminergic imbalances and dysfunction of the striatal dopamine transporter.
基金supported by National Science Foundation Grant No.2123824.
文摘Microrobots powered by an external magnetic field could be used for sophisticated medical applications such as cell treatment,micromanipulation,and noninvasive surgery inside the body.Untethered microrobot applications can benefit from haptic technology and telecommunication,enabling telemedical micro-manipulation.Users can manipulate the microrobots with haptic feedback by interacting with the robot operating system remotely in such applications.Artificially created haptic forces based on wirelessly transmitted data and model-based guidance can aid human operators with haptic sensations while manipulating microrobots.The system presented here includes a haptic device and a magnetic tweezer system linked together using a network-based teleoperation method with motion models in fluids.The magnetic microrobots can be controlled remotely,and the haptic interactions with the remote environment can be felt in real time.A time-domain passivity controller is applied to overcome network delay and ensure stability of communication.This study develops and tests a motion model for microrobots and evaluates two image-based 3D tracking algorithms to improve tracking accuracy in various Newtonian fluids.Additionally,it demonstrates that microrobots can group together to transport multiple larger objects,move through microfluidic channels for detailed tasks,and use a novel method for disassembly,greatly expanding their range of use in microscale operations.Remote medical treatment in multiple locations,remote delivery of medication without the need for physical penetration of the skin,and remotely controlled cell manipulations are some of the possible uses of the proposed technology.
基金supported by the Science and Technology Development Fund of Macao SAR(File No.0117/2024/AMJ)University of Macao(MYRG-GRG2023-00041-FST-UMDF,MYRG-GRG2024-00121-FST,MYRG-CRG2024-00014-FST-ICI)Zhuhai UM Science&Technology Research Institute(CP-009-2024).
文摘In the realm of virtual reality(VR),haptic feedback is integral to enhance the immersive experience;yet,existing wearable devices predominantly rely on skin contact feedback,lacking options for compact and non-contact breeze-sense feedback.Herein,we propose a compact and non-contact working model piezoelectret actuator for providing a gentle and safe breeze sensation.This easy-fabricated and flexible breeze-sense generator with thickness around 1 mm generates air flow pressure up to~163 Pa,which is significantly sensed by human skin.In a typical demonstration,the breeze-sense generators array showcases its versatility by employing multiple coded modes for non-contact information transmitting.The thin thinness and good flexibility facilitate seamless integration with wearable VR setups,and the wearable arrays empower volunteers to precisely perceive the continuous and sudden breeze senses in the virtual environments.This work is expected to inspire developing new haptic feedback devices that play pivotal roles in human-machine interfaces for VR applications.
文摘IntuiGrasp is a novel three-fingered dexterous hand that pioneers bio-inspired demonstrations with intuitive priors(BDIP)to bridge the gap between human tactile intuition and robotic execution.Unlike conven-tional programming,BDIP leverages human's innate priors(e.g.,“A pack of tissues requires gentle grasps,cups demand firm contact”)by enabling real-time transfer of gesture and force policies during physical demon-stration.When a human demonstrator wears IntuiGrasp,driven rings provide real-time haptic feedback on contact stress and slip,while inte-grated tactile sensors translate these human policies into image data,offering valuable data for imitation learning.In this study,human teachers use IntuiGrasp to demonstrate how to grasp three types of objects:a cup,a crumpled tissue pack,and a thin playing card.IntuiGrasp translates the policies for grasping these objects into image information that describes tactile sensations in real time.
基金Supported by the Natienal Natural Science Foundation of China(U23A20287).
文摘Background Haptic feedback plays a crucial role in virtual reality(VR)interaction,helping to improve the precision of user operation and enhancing the immersion of the user experience.Instrumental haptic feedback in virtual environments is primarily realized using grounded force or vibration feedback devices.However,improvements are required in terms of the active space and feedback realism.Methods We propose a lightweight and flexible haptic feedback glove that can haptically render objects in VR environments via kinesthetic and vibration feedback,thereby enabling users to enjoy a rich virtual piano-playing experience.The kinesthetic feedback of the glove relies on a cable-pulling mechanism that rotates the mechanism and pulls the two cables connected to it,thereby changing the amount of force generated to simulate the hardness or softness of the object.Vibration feedback is provided by small vibration motors embedded in the bottom of the fingertips of the glove.We designed a piano-playing scenario in the virtual environment and conducted user tests.The evaluation metrics were clarity,realism,enjoyment,and satisfaction.Results A total of 14 subjects participated in the test,and the results showed that our proposed glove scored significantly higher on the four evaluation metrics than the nofeedback and vibration feedback methods.Conclusions Our proposed glove significantly enhances the user experience when interacting with virtual objects.
基金Supported by the National Key Research and Development Program(2017YFB1002803)the National Natural Science Foundation of China under the grants(61572055,61633004).
文摘Immersion, interaction, and imagination are three features of virtual reality (VR). Existing VR systems possess fairly realistic visual and auditory feedbacks, and however, are poor with haptic feedback, by means of which human can perceive the physical world via abundant haptic properties. Haptic display is an interface aiming to enable bilateral signal communications between human and computer, and thus to greatly enhance the immersion and interaction of VR systems. This paper surveys the paradigm shift of haptic display occurred in the past 30 years, which is classified into three stages, including desktop haptics, surface haptics, and wearable haptics. The driving forces, key technologies and typical applications in each stage are critically reviewed. Toward the future high-fidelity VR interaction, research challenges are highlighted concerning handheld haptic device, multimodal haptic device, and high fidelity haptic rendering. In the end, the importance of understanding human haptic perception for designing effective haptic devices is addressed.
文摘BACKGROUND Perception is frequently impaired in patients with Alzheimer’s disease(AD).Several patients exhibit visual or haptic hallucinations.CASE SUMMARY A 71-year-old Chinese man presented with visual and haptic hallucinations he had been experiencing for 2 weeks.The clinical manifestations were the feeling of insects crawling and biting the limbs and geison.He looked for the insects while itching and scratching,which led to skin breakage on the limbs.He was treated with topical and anti-allergic drugs in several dermatology departments without any significant improvement.After admission,the patient was administered risperidone(0.5 mg)and duloxetine(2 mg/day).One week later,the dose of risperidone was increased to 2 mg/day,and that of duloxetine was increased to 60 mg/day.After 2 weeks of treatment,the patient’s sensation of insects crawling and biting disappeared,and his mood stabilized.CONCLUSION This patient manifested psychiatric behavioral symptoms caused by AD brain atrophy.It was important to re-evaluate the patient’s cognitive-psychological status when the patient repeatedly went to the hospital for treatment.Follow-up attention to cognitive function and the consideration of perceptual deficits as early manifestations of AD should be considered.
文摘Haptic is the modality that complements traditional multimedia,i.e.,audiovisual,to evolve the next wave of innovation at which the Internet data stream can be exchanged to enable remote skills and control applications.This will require ultra-low latency and ultra-high reliability to evolve the mobile experience into the era of Digital Twin and Tactile Internet.While the 5th generation of mobile networks is not yet widely deployed,Long-Term Evolution(LTE-A)latency remains much higher than the 1 ms requirement for the Tactile Internet and therefore the Digital Twin.This work investigates an interesting solution based on the incorporation of Software-defined networking(SDN)and Multi-access Mobile Edge Computing(MEC)technologies in an LTE-A network,to deliver future multimedia applications over the Tactile Internet while overcoming the QoS challenges.Several network scenarios were designed and simulated using Riverbed modeler and the performance was evaluated using several time-related Key Performance Indicators(KPIs)such as throughput,End-2-End(E2E)delay,and jitter.The best scenario possible is clearly the one integrating MEC and SDN approaches,where the overall delay,jitter,and throughput for haptics-attained 2 ms,0.01 ms,and 1000 packets per second.The results obtained give clear evidence that the integration of,both SDN and MEC,in LTE-A indicates performance improvement,and fulfills the standard requirements in terms of the above KPIs,for realizing a Digital Twin/Tactile Internet-based system.
文摘The utilization of high-resolution haptic feedback devices in a virtual reality(VR)environment can increase the precision of controlling remotely operated vehicles and reduce training costs for subsea construction operations.This paper introduces a novel flexible-driven wearable pin-array device.The spatial separation of the control box and actuator allows the device to attain natural and seamless interactive movements while delivering high-density haptic feedback in VR.The pin array consists of 25 haptic pin modules that run on a linear servo motor via a flexible shaft for force transmission.The analysis and calculation of the flexible transmission resistance effect using the haptic pin module's shaft length and bending radius were conducted.A series of experiments was performed to gather comprehensive data on the pin module's output,transmission resistance and error,and response delay to optimize its structural design and transmission strategy.The device's effectiveness in rendering shape and coarse texture was evaluated via two user studies.The results affirm that the introduced device enables users to precisely discern seven shapes and four distinct coarse surfaces.
基金supported in part by the Jiangsu Provincial Natural Science Foundation for Excellent Young Scholars(Grant No.BK20170089)in part by the National Natural Science Foundation of China(Grant No.61671474)in part by the Jiangsu Provincial Natural Science Fund for Outstanding Young Scholars(Grant No.BK20180028).
文摘Haptic communications is recognized as a promising enabler of extensive services by enabling real-time haptic control and feedback in remote environments,e.g.,teleoperation and autonomous driving.Considering the strict transmission requirements on reliability and latency,Device-to-Device(D2D)communications is introduced to assist haptic communications.In particular,the teleoperators with poor channel quality are assisted by auxiliaries,and each auxiliary and its corresponding teleoperator constitute a D2D pair.However,the haptic interaction and the scarcity of radio resources pose severe challenges to the resource allocation,especially facing the sporadic packet arrivals.First,the contentionbased access scheme is applied to achieve low-latency transmission,where the resource scheduling latency is omitted and users can directly access available resources.In this context,we derive the reliability index of D2D pairs under the contention-based access scheme,i.e.,closed-loop packet error probability.Then,the reliability performance is guaranteed by bidirectional power control,which aims to minimize the sum packet error probability of all D2D pairs.Potential game theory is introduced to solve the problem with low complexity.Accordingly,a distributed power control algorithm based on synchronous log-linear learning is proposed to converge to the optimal Nash Equilibrium.Experimental results demonstrate the superiority of the proposed learning algorithm.
文摘Background The sense of touch plays a crucial role in interactive behavior within virtual spaces,particularly when visual attention is absent.Although haptic feedback has been widely used to compensate for the lack of visual cues,the use of tactile information as a predictive feedforward cue to guide hand movements remains unexplored and lacks theoretical understanding.Methods This study introduces a fingertip aero-haptic rendering method to investigate its effectiveness in directing hand movements during eyes-free spatial interactions.The wearable device incorporates a multichannel micro-airflow chamber to deliver adjustable tactile effects on the fingertips.Results The first study verified that tactile directional feedforward cues significantly improve user capabilities in eyes-free target acquisition and that users rely heavily on haptic indications rather than spatial memory to control their hands.A subsequent study examined the impact of enriched tactile feedforward cues on assisting users in determining precise target positions during eyes-free interactions,and assessed the required learning efforts.Conclusions The haptic feedforward effect holds great practical promise in eyeless design for virtual reality.We aim to integrate cognitive models and tactile feedforward cues in the future,and apply richer tactile feedforward information to alleviate users'perceptual deficiencies.
文摘Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the body.For some time,efforts have been made to improve surgical pre training through practical exercises on abstracted and reduced models.Methods The authors strive for a portable,easy to use and cost-effective Virtual Reality-based(VR)laparoscopic pre-training platform and therefore address the question of how such a system has to be designed to achieve the quality of today's gold standard using real tissue specimens.Current VR controllers are limited regarding haptic feedback.Since haptic feedback is necessary or at least beneficial for laparoscopic surgery training,the platform to be developed consists of a newly designed prototype laparoscopic VR controller with haptic feedback,a commercially available head-mounted display,a VR environment for simulating a laparoscopic surgery,and a training concept.Results To take full advantage of benefits such as repeatability and cost-effectiveness of VR-based training,the system shall not require a tissue sample for haptic feedback.It is currently calculated and visually displayed to the user in the VR environment.On the prototype controller,a first axis was provided with perceptible feedback for test purposes.Two of the prototype VR controllers can be combined to simulate a typical both-handed use case,e.g.,laparoscopic suturing.A Unity based VR prototype allows the execution of simple standard pre-trainings.Conclusions The first prototype enables full operation of a virtual laparoscopic instrument in VR.In addition,the simulation can compute simple interaction forces.Major challenges lie in a realistic real-time tissue simulation and calculation of forces for the haptic feedback.Mechanical weaknesses were identified in the first hardware prototype,which will be improved in subsequent versions.All degrees of freedom of the controller are to be provided with haptic feedback.To make forces tangible in the simulation,characteristic values need to be determined using real tissue samples.The system has yet to be validated by cross-comparing real and VR haptics with surgeons.
基金Supported by the National Natural Science Foundation of China(52175493)the National Key Research and Development Program of China(2020YFB2104400).
文摘An increasing number of studies have focused on providing rich tactile feedback in virtual reality interactive scenarios.In this study,we addressed a tapping scenario in virtual reality by designing MatStick,a solution capable of offering diverse tapping sensations.MatStick utilizes a soft physical base to provide force feedback and modulates the instantaneous vibration of the base using a voice coil motor,thereby altering the perception of the base material.We conducted two psychophysical experiments and a subjective evaluation to assess the capabilities of MatStick.The results demonstrate that MatStick can deliver rich tapping sensations.Although users may find it challenging to directly correlate the tapping sensation with the actual physical material based solely on tactile feedback,in immersive scenarios combined with visual and auditory cues,MatStick significantly enhances the user's interaction experience.
