Showing papers on "Haptic technology published in 2007"

Haptic feedback for touchpads and other touch control

Abstract: A haptic feedback planar touch control used to provide input to a computer. A touch input device includes a planar touch surface that inputs a position signal to a processor of the computer based on a location of user contact on the touch surface. The computer can position a cursor in a displayed graphical environment based at least in part on the position signal, or perform a different function. At least one actuator is also coupled to the touch input device and outputs a force to provide a haptic sensation to the user contacting the touch surface. The touch input device can be a touchpad separate from the computer's display screen, or can be a touch screen. Output haptic sensations on the touch input device can include pulses, vibrations, and spatial textures. The touch input device can include multiple different regions to control different computer functions.

Apparatus and method for touch screen interaction based on tactile feedback and pressure measurement

Abstract: An apparatus includes a display section with a touch screen, and the touch screen is adapted to display at least one graphical user interface object and detect a touch position on the touch screen. The apparatus has a haptic feedback generating unit attached to the touch screen and is adapted to generating haptic feedback. A pressure sensing unit is attached to the touch screen and adapted to detect pressure applied to the touch screen. A controller section is adapted to control and drive the display section. The graphical user interface object displayed on the touch screen has a plurality of logical states. The controller section determines a current logical state of the graphical user interface object and a form of the haptic feedback to be generated depending on the detected touch position.

Haptic device with indirect haptic feedback

Abstract: A haptic device provides indirect haptic feedback and virtual texture sensations to a user by modulation of friction of a touch surface of the device in response to one or more sensed parameters and/or time. The sensed parameters can include, but are not limited to, sensed position of the user's finger, derivatives of sensed finger position such as velocity and/or acceleration, sensed finger pressure, and/or sensed direction of motion of the finger. The touch surface is adapted to be touched by a user's bare finger, thumb or other appendage and/or by an instrument such as a stylus held by the user.

T-PaD: Tactile Pattern Display through Variable Friction Reduction

Abstract: In this paper we discuss the theory, design and construction of a haptic display for creating texture sensations through variations in surface friction Ultrasonic frequency, low amplitude vibrations between two flat plates have been shown to create a squeeze film of air between the two plate surfaces thereby reducing the friction (Salbu, 1964; Weisendanger, 2001) We show that a reduction of friction will also occur between a human finger and a vibrating plate Thus, a vibrating plate can serve as a haptic interface The amplitude of vibration can also be correlated to the amount of friction reduction between the plate and the finger Varying the surface friction between the finger and the haptic interface is a way of indirectly controlling shear forces on the finger during active exploration Using finger position and velocity feedback on the display allows for the creation of spatial texture sensations

Modeling of Force Sensing and Validation of Disturbance Observer for Force Control

Abstract: Controlling robots in contact with the environment is an important problem in industry applications. Generally, a force sensor is used for sensing the external force. It is well known that information of a force sensor has much noise. Furthermore, unstable state is also caused by the narrow bandwidth of force information by a force sensor. This paper shows that stable contact with the environment is difficult when a force sensor is used because of its soft mechanical structure and narrow bandwidth of force sensing. In order to solve the instability of force control, the disturbance observer is implemented instead of the force sensor. The disturbance observer can observe the external force without force sensors. When the disturbance observer is implemented in a robot, a force control system does not include a soft mechanism between a robot and the environment. Since a robot can detect the environmental information directly, a wide bandwidth of force sensing is attained. In this way, this paper solves the problems of force control by considering the force sensing method without changing the control architecture, and the ability of force control is improved. Experimental results show viability of the proposed method

Haptic interface for touch screen embodiments

Abstract: A haptic feedback touch control used to provide input to a computer. A touch input device includes a planar touch surface that provides position information to a computer based on a location of user contact. The computer can position a cursor in a displayed graphical environment based at least in part on the position information, or perform a different function. At least one actuator is also coupled to the touch input device and outputs a force to provide a haptic sensation to the user. The actuator can move the touchpad laterally, or a separate surface member can be actuated. A flat E-core actuator, piezoelectric actuator, or other types of actuators can be used to provide forces. The touch input device can include multiple different regions to control different computer functions.

Haptic virtual fixtures for robot-assisted manipulation

Abstract: Haptic virtual fixtures are software-generated force and position signals applied to human operators in order to improve the safety, accuracy, and speed of robot-assisted manipulation tasks. Virtual fixtures are effective and intuitive because they capitalize on both the accuracy of robotic systems and the intelligence of human operators. In this paper, we discuss the design, analysis, and implementation of two categories of virtual fixtures: guidance virtual fixtures, which assist the user in moving the manipulator along desired paths or surfaces in the workspace, and forbidden-region virtual fixtures, which prevent the manipulator from entering into forbidden regions of the workspace. Virtual fixtures are analyzed in the context of both cooperative manipulation and telemanipulation systems, considering issues related to stability, passivity, human modeling, and applications.

Haptic Virtual Fixtures for Robot-Assisted Manipulation

Abstract: Haptic virtual fixtures are software-generated force and position signals applied to human operators in order to improve the safety, accuracy, and speed of robot-assisted manipulation tasks. Virtual fixtures are effective and intuitive because they capitalize on both the accuracy of robotic systems and the intelligence of human operators. In this paper, we discuss the design, analysis, and implementation of two categories of virtual fixtures: guidance virtual fixtures, which assist the user in moving the manipulator along desired paths or surfaces in the workspace, and forbidden-region virtual fixtures, which prevent the manipulator from entering into forbidden regions of the workspace. Virtual fixtures are analyzed in the context of both cooperative manipulation and telemanipulation systems, considering issues related to stability, passivity, human modeling, and applications.

Haptic Feedback Enhances Force Skill Learning

Abstract: This paper explores the use of haptic feedback to teach an abstract motor skill that requires recalling a sequence of forces. Participants are guided along a trajectory and are asked to learn a sequence of one-dimensional forces via three paradigms: haptic training, visual training, or combined visuohaptic training. The extent of learning is measured by accuracy of force recall. We find that recall following visuohaptic training is significantly more accurate than recall following visual or haptic training alone, although haptic training alone is inferior to visual training alone. This suggests that in conjunction with visual feedback, haptic training may be an effective tool for teaching sensorimotor skills that have a force-sensitive component to them, such as surgery. We also present a dynamic programming paradigm to align and compare spatiotemporal haptic trajectories

Optimal integration of shape information from vision and touch

Abstract: Many tasks can be carried out by using several sources of information. For example, an object's size and shape can be judged based on visual as well as haptic cues. It has been shown recently that human observers integrate visual and haptic size information in a statistically optimal fashion, in the sense that the integrated estimate is most reliable (Ernst and Banks in Nature 415:429-433, 2002). In the present study, we tested whether this holds also for visual and haptic shape information. In previous studies virtual stimuli were used to test for optimality in integration. Virtual displays may, however, contain additional inappropriate cues that provide conflicting information and thus affect cue integration. Therefore, we studied optimal integration using real objects. Furthermore, we presented visual information via mirrors to create a spatial separation between visual and haptic cues while observers saw their hand touching the object and thus, knew that they were seeing and feeling the same object. Does this knowledge promote integration even though signals are spatially discrepant which has been shown to lead to a breakdown of integration (Gepshtein et al. in J Vis 5:1013-1023, 2005)? Consistent with the model predictions, observers weighted visual and haptic cues to shape according to their reliability: progressively more weight was given to haptics when visual information became less reliable. Moreover, the integrated visual-haptic estimate was more reliable than either unimodal estimate. These findings suggest that observers integrate visual and haptic shape information of real 3D objects. Thereby, knowledge that multisensory signals arise from the same object seems to promote integration.

Do it yourself haptics: part I

Abstract: This article is the first of a two-part series intended as an introduction to haptic interfaces. Together they provide a general introduction to haptic interfaces, their construction, and application design. Haptic interfaces comprise hardware and software components aiming at providing computer-controlled, programmable sensations of mechanical nature, i.e., pertaining to the sense of touch. In Part I, we describe methods that have been researched and developed to date to achieve the generation of haptic sensations, the means to construct experimental devices of modest complexity, and the software components needed to drive them. In Part II of this series, we will describe some basic concepts of haptic interaction design together with several interesting applications based on this technology.

Virtual reality in neurosurgical education: part-task ventriculostomy simulation with dynamic visual and haptic feedback.

Abstract: OBJECTIVE: Mastery of the neurosurgical skill set involves many hours of supervised intraoperative training. Convergence of political, economic, and social forces has limited neurosurgical resident operative exposure. There is need to develop realistic neurosurgical simulations that reproduce the operative experience, unrestricted by time and patient safety constraints. Computer-based, virtual reality platforms offer just such a possibility. The combination of virtual reality with dynamic, three-dimensional stereoscopic visualization, and haptic feedback technologies makes realistic procedural simulation possible. Most neurosurgical procedures can be conceptualized and segmented into critical task components, which can be simulated independently or in conjunction with other modules to recreate the experience of a complex neurosurgical procedure. METHODS: We use the ImmersiveTouch (ImmersiveTouch, Inc., Chicago, IL) virtual reality platform, developed at the University of Illinois at Chicago, to simulate the task of ventriculostomy catheter placement as a proof-of-concept. Computed tomographic data are used to create a virtual anatomic volume. RESULTS: Haptic feedback offers simulated resistance and relaxation with passage of a virtual three-dimensional ventriculostomy catheter through the brain parenchyma into the ventricle. A dynamic three-dimensional graphical interface renders changing visual perspective as the user's head moves. The simulation platform was found to have realistic visual, tactile, and handling characteristics, as assessed by neurosurgical faculty, residents, and medical students. CONCLUSION: We have developed a realistic, haptics-based virtual reality simulator for neurosurgical education. Our first module recreates a critical component of the ventriculostomy placement task. This approach to task simulation can be assembled in a modular manner to reproduce entire neurosurgical procedures.

Systems and methods for sculpting virtual objects in a haptic virtual reality environment

Abstract: A user of a virtual object or computer model uses a haptic interface device in the real world to manipulate a virtual tool in a virtual environment to interact and modify the virtual object. The user uses the virtual tool in a sculpting mode to modify the shape of the virtual object by adding, removing, or modifying the material of the object. The user feels an interaction force from the virtual tool as it interacts with and modifies the virtual object. The designer can set geometric constraints, such as a constraint point, constraint line, or constraint surface, to limit or guide the movement of the virtual tool.

A Haptic Knob for Rehabilitation of Hand Function

Abstract: This paper describes a novel two-degree-of-freedom robotic interface to train opening/closing of the hand and knob manipulation. The mechanical design, based on two parallelogram structures holding an exchangeable button, offers the possibility to adapt the interface to various hand sizes and finger orientations, as well as to right-handed or left-handed subjects. The interaction with the subject is measured by means of position encoders and four force sensors located close to the output measuring grasping and insertion forces. Various knobs can be mounted on the interface, including a cone mechanism to train a complete opening movement from a strongly contracted and closed hand to a large opened position. We describe the design based on measured biomechanics, the redundant safety mechanisms as well as the actuation and control architecture. Preliminary experiments show the performance of this interface and some of the possibilities it offers for the rehabilitation of hand function.

Communicating emotion through a haptic link: Design space and methodology

Abstract: Communication of affect across a distance is not well supported by current technology, despite its importance to interpersonal interaction in modern lifestyles. Touch is a powerful conduit for emotional connectedness, and thus mediating haptic (touch) displays have been proposed to address this deficiency; but suitable evaluative methodology has been elusive. In this paper, we offer a first, structured examination of a design space for haptic support of remote affective communication, by analyzing the space and then comparing haptic models designed to manipulate its key dimensions. In our study, dyads (intimate pairs or strangers) are asked to communicate specified emotions using a purely haptic link that consists of virtual models rendered on simple knobs. These models instantiate both interaction metaphors of varying intimacy, and representations of virtual interpersonal distance. Our integrated objective and subjective observations imply that emotion can indeed be communicated through this medium, and confirm that the factors examined influence emotion communication performance as well as preference, comfort and connectedness. The proposed design space and the study results have implications for future efforts to support affective communication using the haptic modality, and the study approach comprises a first model for systematic evaluation of haptically expressed affect.

Modeling the effects of delayed haptic and visual feedback in a collaborative virtual environment

Abstract: Collaborative virtual environments (CVEs) enable two or more people, separated in the real world, to share the same virtual “space” They can be used for many purposes, from teleconferencing to training people to perform assembly tasks Unfortunately, the effectiveness of CVEs is compromised by one major problem: the delay that exists in the networks linking users together Whilst we have a good understanding, especially in the visual modality, of how users are affected by delayed feedback from their own actions, little research has systematically examined how users are affected by delayed feedback from other people, particularly in environments that support haptic (force) feedback The current study addresses this issue by quantifying how increasing levels of latency affect visual and haptic feedback in a collaborative target acquisition task Our results demonstrate that haptic feedback in particular is very sensitive to low levels of delay Whilst latency affects visual feedback from 50 ms, it impacts on haptic task performance 25 ms earlier, and causes the haptic measures of performance deterioration to rise far more steeply than visual The “impact-perceive-adapt” model of user performance, which considers the interaction between performance measures, perception of latency, and the breakdown of perception of immediate causality, is proposed as an explanation for the observed pattern of performance

Haptic effects with proximity sensing

Abstract: A method of generating haptic effects on a device includes detecting the presence of an object near an input area of the device and generating a haptic effect on the device in response to the presence detection.

Mobile apparatus having tactile feedback function

Abstract: A haptic display includes at least one haptic device that can give tactile feedback instead of visible feedback. Each of the haptic devices converts a signal from a signal producing unit into force or tactile pattern. The haptic device does not require a large mass, so that it can be provided on almost any portion or part within the body of a mobile apparatus. For example, the haptic device can be embedded under a touch panel display that constitutes both input and output device. By providing the haptic devices under respective menu/function button areas displayed on the touch panel display, it is possible to stimulate the specific button in response to the user-input-operation, thereby directly providing the tactile feedback to the user's finger touching the corresponding button.

High-Fidelity Bilateral Teleoperation Systems and the Effect of Multimodal Haptics

Abstract: In master-slave teleoperation applications that deal with a delicate and sensitive environment, it is important to provide haptic feedback of slave/environment interactions to the user's hand as it improves task performance and teleoperation transparency (fidelity), which is the extent of telepresence of the remote environment available to the user through the master-slave system. For haptic teleoperation, in addition to a haptics-capable master interface, often one or more force sensors are also used, which warrant new bilateral control architectures while increasing the cost and the complexity of the teleoperation system. In this paper, we investigate the added benefits of using force sensors that measure hand/master and slave/environment interactions and of utilizing local feedback loops on the teleoperation transparency. We compare the two-channel and the four-channel bilateral control systems in terms of stability and transparency, and study the stability and performance robustness of the four-channel method against nonidealities that arise during bilateral control implementation, which include master-slave communication latency and changes in the environment dynamics. The next issue addressed in the paper deals with the case where the master interface is not haptics capable, but the slave is equipped with a force sensor. In the context of robotics-assisted soft-tissue surgical applications, we explore through human factors experiments whether slave/environment force measurements can be of any help with regard to improving task performance. The last problem we study is whether slave/environment force information, with and without haptic capability in the master interface, can help improve outcomes under degraded visual conditions.

Multiple mode haptic feedback system

Abstract: A haptic effect device includes a housing and a touchscreen coupled to the housing through a suspension. An actuator is coupled to the touchscreen. The suspension is tuned so that when the actuator generates first vibrations at a first frequency, the first vibrations are substantially isolated from the housing and are applied on the touchscreen to simulate a mechanical button. Further, when the actuator generates second vibrations at a second frequency, the second vibrations are substantially passed through to the housing to create a vibratory alert.

Haptic apparatus and coaching method for improving vehicle fuel economy

Abstract: An apparatus is disclosed that includes a haptic actuator operatively associated with a pedal assembly of the vehicle, a human-machine interface (HMI) for enabling the driver to select between a plurality of fuel savings settings, and a controller coupled to a data interface in the vehicle and the HMI interface for causing the haptic actuator to provide feedback to the driver when an aspect of vehicle operation crosses at least one of a plurality of speed and acceleration thresholds responsive to the HMI setting. Additionally, a coaching method provides haptic-based feedback that will not interfere with the operation of the vehicle. This method of closed-loop feedback provides a timely signal to the driver in a way that will encourage a change in driver style over time, such as backing off the accelerator pedal to accelerate at a lower rate and braking earlier with less intensity. As not all driver preferences are the same under all conditions, the HMI selector will help coach the driver by providing feedback that best fits their driving preference at the particular time.

A Six Degree-of-Freedom God-Object Method for Haptic Display of Rigid Bodies with Surface Properties

Abstract: This paper describes a generalization of the god-object method for haptic interaction between rigid bodies. Our approach separates the computation of the motion of the six degree-of-freedom god-object from the computation of the force applied to the user. The motion of the god-object is computed using continuous collision detection and constraint-based quasi-statics, which enables high-quality haptic interaction between contacting rigid bodies. The force applied to the user is computed using a novel constraint-based quasi-static approach, which allows us to suppress force artifacts typically found in previous methods. The constraint-based force applied to the user, which handles any number of simultaneous contact points, is computed within a few microseconds, while the update of the configuration of the rigid god-object is performed within a few milliseconds for rigid bodies containing up to tens of thousands of triangles. Our approach has been successfully tested on complex benchmarks. Our results show that the separation into asynchronous processes allows us to satisfy the different update rates required by the haptic and visual displays. Force shading and textures can be added and enlarge the range of haptic perception of a virtual environment. This paper is an extension of M. Ortega et al., [2006]

Providing enhanced haptic feedback effects

Abstract: Method and apparatus for providing tactile sensations. For one embodiment a first frequency at which to output a tactile sensation is received. A second frequency higher than the first frequency is determined. The second frequency is based on a frequency at which an inertial actuator outputs a second tactile sensation. A waveform having the first frequency and a waveform having the second frequency is combined to produce a signal configured to cause a composite tactile sensation at the second frequency, the composite tactile sensation conveying the first frequency.

The body surface as a communication system: The state of the art after 50 years

Abstract: The suggestion that the body surface might be used as an additional means of presenting information to human-machine operators has been around in the literature for nearly 50 years Although recent technological advances have made the possibility of using the body as a receptive surface much more realistic, the fundamental limitations on the human information processing of tactile stimuli presented across the body surface are, however, still largely unknown This literature review provides an overview of studies that have attempted to use vibrotactile interfaces to convey information to human operators The importance of investigating any possible central cognitive limitations (ie, rather than the peripheral limitations, such as related to sensory masking, that were typically addressed in earlier research) on tactile processing for the most effective design of body interfaces is highlighted The applicability of the constraints emerging from studies of tactile processing under conditions of unisensory (ie, purely tactile) stimulus presentation, to more ecologically valid conditions of multisensory stimulation, is also discussed Finally, the results obtained from recent studies of tactile information processing under conditions of multisensory stimulation are described, and their implications for haptic/tactile interface design elucidated

Assessment of faculty perception of content validity of PerioSim, a haptic-3D virtual reality dental training simulator.

Abstract: Haptic technology (sense of touch) along with 3D-virtual reality (VR) graphics, creating lifelike training simulations, was used to develop a dental training simulator system (PerioSim). This preliminary study was designed to evaluate whether faculty considered PerioSim realistic and useful for training and evaluating basic procedural skills of students. The haptic device employed was a PHANToM and the simulator a Dell Xeon 530 workstation with 3D, VR oral models and instruments viewed on a stereoscopic monitor. An onscreen VR periodontal probe or explorer was manipulated by operating the PHANToM for sensing lifelike contact and interactions with the teeth and gingiva. Thirty experienced clinical dental and dental hygiene faculty judged the realism of the system. A PowerPoint presentation on one screen provided instructions for the simulator use with the 3D, VR simulator on a second stereoscopic monitor viewed with 3D goggles. Faculty/practitioners found the images very realistic for teeth and instruments, but less so for gingiva. Tactile sensation was realistic for teeth but not so for gingiva. The onscreen instructions were very useful with high potential for teaching. Faculty members anticipated incorporating this device into teaching and were enthusiastic about its potential for evaluating students' basic procedural skills. This study suggests that the preliminary "evidence-of-concept" was successful and PerioSim may aid students in developing necessary dental tactile skills.

Evaluating the Effect of Force Feedback in Cell Injection

Abstract: Conventional methods of manipulating individual biological cells have been prevalent in the field of molecular biology. These methods do not have the ability to provide force feedback to an operator. Poor control of cell injection force is one of the primary reasons for low success rates in cell injection and transgenesis in particular. Therefore, there exists a need to incorporate force feedback into a cell injection system. We have developed a force feedback interface, which has the capability of measuring forces in the range of and provide a haptic display of the cell injection forces in real time. Using this force feedback interface, we performed several human factors studies to evaluate the effect of force feedback on cell injection outcomes. We tested our system with 40 human subjects and our experimental results indicate that the subjects were able to feel the cell injection force and confirmed our research hypothesis that the use of combined vision and force feedback leads to a higher success rate in cell injection task compared to using vision feedback alone.

Haptic health feedback monitoring

Abstract: A haptic health feedback monitor includes a health parameter monitor that detects a health parameter. A haptic feedback generator receives the health parameter and compares it to a predetermined level. If the health parameter reaches or exceeds the level, a type of haptic feedback to generate is determined. The type of feedback may depend on which predetermined level is reached or exceeded. The haptic feedback generator then generates the determined type of haptic feedback.

Method and apparatus for providing a fixed relief touch screen with locating features using deformable haptic surfaces

Abstract: A method and apparatus for an electronic interface device capable of providing a fixed relief touch screen with locating features using deformable haptic surfaces are disclosed. The device, in one embodiment, includes a haptic mechanism and a touch-sensitive surface. The haptic mechanism provides haptic feedback in response to an activating command. The touch-sensitive surface is capable of changing its surface texture from a first surface characteristic to a second surface characteristic in response to the haptic feedback. For example, the first surface characteristic may be coarse texture while the second surface characteristic may be smooth texture.

Virtual-Environment Modeling and Correction for Force-Reflecting Teleoperation With Time Delay

Abstract: Virtual environment (VE) is an effective method to deal with time delay in teleoperation, but it depends heavily on the accuracy of the virtual model. In this paper, a novel approach is proposed to create and verify geometric and dynamic model of the remote physical environment. The geometric errors of the virtual model are corrected by overlaying the graphics over video images and also by fusing the position and force information from the remote. A sliding-average least-square algorithm is proposed to identify dynamic parameters of the remote environment, and the corresponding virtual-model parameters are updated online to keep equal to the real environment. The VE-based teleoperation system developed in our laboratory is described. Experimental results show that the relative errors of forces provided by the corrected VE are 2.82%, 2.22%, and 2.60%, respectively, with time delay of 5, 10, and 15 s. Results indicate that VE built by this method can provide the operator with appropriate predictive virtual forces with a certain time delay