Haptik-Dokunma Algısı ve Cihazları Haptic Perception and Devices

Haptic science Haptics is the «science of touch».

What is Haptics? adj. Of or relating to the sense of touch; tactile. [Greek haptikos, from haptesthai, to grasp, touch.] Haptics involves both proprioceptive and tactile senses, in concert with other senses. adj. The science of applying touch (tactile) sensation and control to interaction with computer applications.

Haptic: is the science of applying tactile, kinesthetic or both sensations to human interaction with computers. It refers to the ability of sensing and/or manipulating objects in a natural or synthetic environment through touch using a haptic interface. El Saddik (U. Ottawa) Tactile (presure, temperature, pain) Kinesthetic (motion, force, muscles) Texture vibration Haptic device // Haptic interface // Haptic rendering

Haptic interface

The Sense of Touch Everyday Tasks Touch is complex: tying a shoelace Dialing a phone Playing a guitar or piano Finding a light switch Using a mouse Touch is complex: tying a shoelace Only bi-directional communication channel – both input & output

Why is Touch Important? Touch-tone phone PC calculator Rich tactile cues Can be done without looking Effortless PC calculator No tactile cues Only visual feedback Painstaking When these mechanoreceptors stop functioning, everyday tasks that have become second nature to you suddenly become impossible. Have you ever tried walking when your leg has fallen asleep or tried tying your shoe after playing in the snow without gloves? The difficulty and clumsiness of those tasks arise not because of a loss of dexterity or motor skills, but because your mechanoreceptors are no longer sending critical information about touch, pressure, stretching, and motion to your brain. Similarly, hitting a home run, a forehand winner, or 300-yard drive would lose a lot of its satisfaction if you didn’t get that “sweet spot” feeling when the ball was struck. So why is it that when you sit down in front of a computer, you are presented solely with visual feedback, and maybe a little auditory feedback? Your primary sensory cortex, the part of your brain responsible for your wonderful, sophisticated sense of touch, may as well go into hibernation since information is presented almost exclusively in text, pictures, and color, but not in textures, shapes, and touch. By adding back the tactile and kinesthetic cues you’ve come to expect in the real world, Immersion is transforming the computing world and human-machine interfaces everywhere with haptics. It’s time to wake up your brain and rouse it from hibernation!

Tactile Perception Provides information about our environment e.g. hot, cold, smooth, rough Provides feedback e.g. when trying to lift an object, press buttons, etc. Difficulties if no feedback?

Haptics

Human skin Surface of average sized adult human: 1.8 m2 (1000 times that of retina) Weight: 5 kg Total number of axons: 1.1*106 Retina: 106 axons, Cochlea: 6*104 axons

Haptics and Vision Fingertip 102 5 ms Ear 104 0.01 ms Information Temporal capacity (bits/sec) acuity Fingertip 102 5 ms Ear 104 0.01 ms Eye 106-109 25 ms

Peripheral Pathways of Touch Mechanoreceptors - pressure, texture, vibration Proprioceptors - body position Nocioceptors Two pathways for pain one fast pathway for sharp pain, one slow pathway for dull pain Thermoreceptors

Four Receptor Types a) Merkel Disks -- constant sources of stimulation over a small area, such as if you were carrying a pebble b) Meissner Corpuscles -- respond best to active touch involved in object exploration c) Ruffini Endings -- constant stimulation over a larger area - also detects skin stretch d) Pacinian Corpuscles -- extremely sensitive over a large receptive field -- blow gently on the palm of your hand

Functional characteristics of Skin Mechanoreceptors: Receptive field size (I = small, II = large) and adaptation rate (FA = fast adapting, SA = slow adapting) Meissner’s Merkel Pacinian Ruffini Corpuscle Cell Complex Corpuscle Ending Receptors Receptive Field Intensity and Time Course of Neural Signal (adaptation) Neural Spike train Stimulus FA I SA I FA II SA II Kandel et. al., 2000

Receptive Field The two-point threshold for any part of the body is determined by the size of the receptive fields and the extent of overlap

Proprioception All muscles have nerve fibers which detect the amount the muscle is stretched All joints have fibers which detect the relative position of each bone Together these allow you to determine the position of every part of your body. [Green]

Proprioception Includes The Vestibular Sense Ocular Motor [Green]

Haptic Interfaces

Haptic Interfaces Fully duplex channel. You can both transmit and receive information simultaneously. Requires very high refresh rates of approx. 1000 Hz for realistic feel. Requires very high spatial resolution. On smooth glass surface, dot of height 1-3 µm and diameter of 550 µm can be detected by the fingertip (Johansson & LaMotte, 1983)

Tactile Technologies Tactile information is produced by perturbing the skin Pins or other mechanical vibrating elements - either alone or in an array, as in devices for Braille display typically used for fingertip stimulation Air jets blow to produce a disturbance Cushions of air can be inflated or deflated to vary pressure on skin Electrical stimulation - low levels of current provide a localized tingling sensation Typically used in gloves, or for larger body areas

Laterotactile Induce sensations of indent from lateral movement of skin

Vibrotactile

Electrotactile

Servomotor mechanical

Tactile Vest

Force-Feedback Technologies Kinesthetic (relating to the feeling of motion) info is produced by exerting mechanical forces Haptic devices movie.. http://www.forcedimension.com/products/medical/movie

MPB Freedom7 and Cubic

CyberForce [Chang]

6DOF Delta

Magnetic Levitation CMU Very high fidelity Small workspace movie

Exoskeleton 5DOF video

Rutgers Hand Master Pneumatic

Foot Haptics (locomotion interface) Omni-directional treadmill Foot-based interfaces Omni video Sarcos Biport Iwata’s GaitMaster

Whole-Body Haptics Sarcos Treadport II Note that the body based system is really ground-based, but the shoulder and elbow should be attached, so it acts as a body-based system. Sarcos Treadport II

CirculaFloor Moving floor tiles An example of “encountered haptics”

Discussion Mechanical aspects are more daunting than for other VR technologies Must handle gross positioning (proprioception) and fine detail (tactile) Burgeoning area 10 years ago, 20 papers a year Now, 1000’s.

Tactile : touch screen Haptics A. García-Alonso September 14, 2005 The Global Gaming Expo (G2E) in Las Vegas this week has seen the debut of an interesting new technology that enables touchscreens to generate tactile cues, promoting a more intuitive and engaging experience. Users perceive that on-screen buttons press and release as if they were physical buttons. In addition, TouchSense tactile sensations can be synchronized with sound and graphical images, creating a more immersive, multisensory experience. Quite clearly the technology will initially be used in the lucrative gambling industry, but we can expect much richer information kiosks and touch screen user interfaces in the future. Touchscreens are increasingly used in casino gaming devices to provide a direct and flexible user interface for on-screen buttons that dynamically change from screen to screen or game to game. Growing numbers of game machines let users choose from a variety of preloaded games. New technology will allow devices to be reconfigured by the operator in real time to tailor the mix offered to suit the time-of-day or clientele. Haptics A. García-Alonso

Tactile Haptics A. García-Alonso The tactile interface device demoed in this video does an impressive comparison between conventional haptic feedback devices that rely on the whole device to vibrate (the big touchscreen box on the right is an example), and a novel interface device designed by NTT’s Junji Watanabe and Osaka University’s Hideyuki Ando, amongst others. The concept itself is stunningly simple- a nail mounted voice coil that vibrates in a manner that causes the stimulus to be perceived as if it were from the finger pad itself. Depending on the visual texture being touched on the screen, the coil vibrates in a manner that mimics the haptic feedback of the texture- a rather realistic effect in our opinion. We can imagine applications for this in areas beyond just assistive technologies- there is much scope for such technologies in the mainstream. In fact, We have seen similar attempts (albeit with conventional haptic feedback devices) in the commercial space already. RIM, the makers of Blackberry, shot back at the iPhone with a full touchscreen, but with a twist. The screen provided haptic feedback upon touch. It was called the next-gen SureType keyboard and it provided the feel of pressing a real button combining vibration with a touchscreen that pushed in when pressed. The technology bombed when released to consumers. The reason was simple, while some loved the physical touch feel the touchcreen had, many still loved the smooth response of the iPhone display. The technology on display at the Techfest 2011 exhibition, shows us two things. 1) How a display can have tactile feedback without having to make the user press against the screen hard and 2) how a gadget like the iPad itself can give tactile feedback by just having a small accessory over it. The best of both worlds! Is this ready for prime time? Perhaps not, but this surely gives us a glimpse of how technology can evolve in future. We can expect some innovation coming out for the visually impaired for sure, but at the same time I do see atleast some use in touchscreen gaming and implementation future smartphones / tablets / computers. A perusal of this project can be done at: http://junji.org/invisibles/ Haptics A. García-Alonso

Tactile Haptics A. García-Alonso

Tactile Haptics A. García-Alonso Fingertracking: Tactile Feedback http://www.ar-tracking.de/Tactile-Feedback-Protoype.223.0.html We present a new tactile feedback system for finger-based interactions in immersive virtual reality applications. The system consists of tracked thimbles for the fingers with shape memory alloy wires wrapped around each thimble. These wires touch the inside of the finger tips and provide an impression when they are shortened. We complement the impression on the finger tips by a subsequent vibration of the wire to generate a perceivable tactile stimulus over a longer period of time. The shortening and relaxation process of the wires as well as the vibration is controlled through a micro-controller. Haptics A. García-Alonso

Body Haptics A. García-Alonso In the latest attempt to more closely align our virtual experiences with tangible sensations in the real world, students at the University of Pennsylvania’s General Robotics, Automation, Sensing and Perception (GRASP) Laboratory have developed the Tactile Gaming Vest. What the wearable piece of technology lacks in fashion sense, it hopes to make up for in experience, bringing a physical component to world of video games. The vest’s chest, shoulders and back have been outfitted with solenoid actuators to deliver powerful vibrations that are tied to the action on the screen. While similar concepts have been created in the past, these models employed pneumatics which have slower response times. During a recent demonstration at the Haptics Symposium 2010, the vest was shown off in conjunction with popular first-person shooter, Half-Life 2, simulating the feeling of gunshots and explosions in real-time. Beyond delivering an additional layer of immersion to gaming and other forms of entertainment, haptics has implications for various real world training scenarios, such as military, driving and medial simulations, where feedback aids in the development process. Haptics A. García-Alonso

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