Perception of spatialized vibrotactile impacts in a hand-held tangible for Virtual Reality

International audienceInformative and realistic haptic feedback significantly enhances virtual reality (VR) manipulation. In particular, vibrotactile feedback (VF) can deliver diverse haptic sensations while remaining relatively simple. This has made it a go-to solution for haptics within hand-held controllers and tangible props for VR. However, VF in hand-helds has solely focused on monolithic vibration of the entire hand-held device. Thus, it is not clear to what extent such hand-held devices could support the delivery of spatialized information within the hand. In this paper, we consider a tangible cylindrical handle that allows interaction with virtual objects extending beyond it. This handle is fitted with a pair of vibrotactile actuators with the objective of providing in-hand spatialized cues indicating direction and distance of impacts. We evaluated its capability for rendering spatialized impacts with external virtual objects. Results show that it performs very well for conveying an impact's direction and moderately well for conveying an impact's distance to the user

Mems sensors controlled haptic forefinger robotic aid

The ability to feel the world through the tools we hold is Haptic Touch. The concept of sensory elements transforming information into touch experience by interacting with things remotely is motivating and challenging. This paper deals with the design and implementation of fore finger direction based robot for physically challenged people, which follows the direction of the Forefinger. The path way of the robot may be either point-to-point or continuous. This sensor detects the direction of the forefinger and the output is transmitted via RF transmitter to the receiver unit. In the receiver section RF receiver which receives corresponding signal will command the microcontroller to move the robot in that particular direction. The design of the system includes microcontroller, MEMS sensor and RF technology. The robot system receives the command from the MEMS sensor which is placed on the fore finger at the transmitter section. Therefore the simple control mechanism of the robot is shown. Experimental results for fore finger based directional robot are enumerated

Pseudo-haptics survey: Human-computer interaction in extended reality & teleoperation

Pseudo-haptic techniques are becoming increasingly popular in human-computer interaction. They replicate haptic sensations by leveraging primarily visual feedback rather than mechanical actuators. These techniques bridge the gap between the real and virtual worlds by exploring the brain’s ability to integrate visual and haptic information. One of the many advantages of pseudo-haptic techniques is that they are cost-effective, portable, and flexible. They eliminate the need for direct attachment of haptic devices to the body, which can be heavy and large and require a lot of power and maintenance. Recent research has focused on applying these techniques to extended reality and mid-air interactions. To better understand the potential of pseudo-haptic techniques, the authors developed a novel taxonomy encompassing tactile feedback, kinesthetic feedback, and combined categories in multimodal approaches, ground not covered by previous surveys. This survey highlights multimodal strategies and potential avenues for future studies, particularly regarding integrating these techniques into extended reality and collaborative virtual environments.info:eu-repo/semantics/publishedVersio

Cicloergómetro háptico para el control del esfuerzo físico del usuario

El presente trabajo está englobado en otro proyecto que abarca el diseño y construcción completa de un cicloergómetro háptico cuyo objetivo es ayudar a mantener al usuario en una franja establecida de pulsaciones por minuto. En el trabajo correspondiente a este TFG se diseñará la parte del sistema que controla el esfuerzo del usuario, la actuación, sin entrar en la parte del control de las pulsaciones por minuto del usuario. El sistema de actuación seleccionado se basa en el acoplamiento de un motor de corriente continua en el sistema de transmisión para crear un par resistente. Los objetivos del proyecto son la selección de los componentes que compondrán el sistema y su correspondiente comprobación mediante simulaciones para ver si están bien dimensionados. Las simulaciones del sistema se realizarán aproximando el sistema como un modelo de cuatro barras y un simulador de fuerza, implementado todo mediante un modelo en Simulink, que se ejecutará y exportará los resultados a través de un archivo Matlab. La versión utilizada de este software es la r2020a.Departamento de Ingeniería de Sistemas y AutomáticaGrado en Ingeniería en Electrónica Industrial y Automátic

A Haptic Feedback System for Lower Limb Amputees Based on Gait Event Detection

Lower limb amputation has significant effects on a person’s quality of life and ability to perform activities of daily living. Prescription of prosthetic device post amputation aims to help restore some degrees of mobility function, however studies have shown evidence of low balance confidence and higher risk of falling among amputee community, especially those suffering from above knee amputation. While advanced prostheses offer better control, they often lack a form of feedback that delivers the awareness of the limb position to the prosthetic user while walking. This research presents the development and evaluation of a wearable skinstretch haptic feedback system intended to deliver cues of two crucial gait events, namely the Initial Contact (IC) and Toe-off (TO) to its wearer. The system comprises a haptic module that applies lateral skin-stretch on the upper leg or the trunk, corresponding to the gait event detection module based on Inertial Measurement Unit (IMU) attached at the shank. The design and development iterations of the haptic module is presented, and characterization of the feedback parameters is discussed. The validation of the gait event detection module is carried out and finally the integration of the haptic feedback system is described. Experimental work with healthy subjects and an amputee indicated good perceptibility of the feedback during static and dynamic (walking) condition, although higher magnitude of stretch was required to perceive the feedback during dynamic condition. User response time during dynamic activity showed that the haptic feedback system is suitable for delivering cues of IC and TO within the duration of the stance phase. In addition, feedback delivered in discernible patterns can be learned and adapted by the subjects. Finally, a case study was carried out with an above-knee amputee to assess the effects of the haptic feedback on spatio-temporal gait parameters and on the vertical ground reaction force during treadmill and overground walking. The research presented in this report introduces a novel design of a haptic feedback device. As such, the outcome includes a well-controlled skin-stretch effect which contributes to the research by investigating skin-stretch feedback for conveying discrete event information rather than conveying direction information as presented in other studies. In addition, it is found that stretch magnitude as small as 3 mm could be perceived in short duration of 150 ms during dynamic condition, making it a suitable alternative to other widely investigated haptic modality such as vibration for ambulatory feedback application. With continuous training, the haptic feedback system could possibly benefit lower limb amputees by creating awareness of the limb placement during ambulation, potentially reducing visual dependency and increasing walking confidence

The Design and Development of an Intelligent Atraumatic Laparoscopic Grasper

A key tool in laparoscopic surgery is the grasper, which is the surgeon’s main means of manipulating tissue within the body. However inappropriate use may lead to tissue damage and poor surgical outcomes. This thesis presents a novel approach to the assessment and prevention of tissue damage caused by laparoscopic graspers. The research focusses on establishing typical grasping characteristics used in surgery and thus developing a model of mechanically induced tissue trauma. A review explored the state-of-the-art in devices for measuring surgical grasping, tissue mechanics, and damage quantification to inform the research. An instrumented grasper was developed to characterise typical surgical tasks, enabling the grasping force and jaw displacement to be measured. This device was then used to quantitatively characterise grasper use in an in-vivo porcine model where the device was used to perform organ retraction and manipulation tasks. From this work, the range of forces and the grasping times used in certain tasks were determined and this information was used to guide the rest of the study. The in-vivo investigation highlighted a need for grasping in a controlled environment where the tissue’s mechanical properties could be studied. A grasper test rig was designed and developed to provide automated controlled grasping of ex-vivo tissue. This allowed the mechanical properties of tissue to be determined and analysed for indications of tissue damage. A series of experimental studies were conducted with this system which showed how the mechanical response of tissue varies depending on the applied grasping force characteristics, and how this is indicative of tissue damage through comparison to histological analysis. These data were then used to develop a model which predicts the likelihood and severity of tissue damage during grasping, based on the input conditions of grasping force and time. The model was integrated into the instrumented grasper system to provide a tool which could enable real-time grading and feedback of grasping during surgery, or be used to inform best practice in training scenarios