27-11-2012, 06:17 PM
A paper presentation on HAPTICS TECHNOLOGY
Haptics.doc (Size: 582.5 KB / Downloads: 39)
Abstract:
In this paper, we define ‘haptics’ as a technology that adds the sense of touch to virtual environments. Users are given the illusion that they are touching or manipulating a real physical object.
We discuss a few hap tic devices like ‘the Logitech mouse’, ‘phantom’ and ‘cyber glove and cyber grasp’ in brief. Next, we explicate how sensors and actuators are used for tracking the position and movement of the haptic device moved by the operator.
We mention the different types of force rendering algorithms. We explain the blocks in force rendering.
Then, we move on to a few applications of hap tic technology. Finally we conclude after mentioning a few future developments.
Introduction
What is haptics?
Haptics refer to sensing and manipulation through touch. The word comes from the Greek ‘haptesthai’, meaning ‘to touch’.
The history of the hap tic interface dates back to the 1950s, when a master-slave system was proposed by goertz (1952). Hap tic interfaces were established out of the field of teleportation, which was then employed in the remote manipulation of radioactive materials. The ultimate goal of the teleportation system was "transparency". That is, a user interacting with the master device in a master-slave pair should not be able to distinguish between using the master controller and manipulating the actual tool itself. Early haptic interface systems were therefore developed purely for telerobotic applications.
Computing contact-response forces:
Humans perceive contact with real objects through sensors (mechanoreceptors) located in their skin, joints, tendons, and muscles. We make a simple distinction between the information these two types of sensors can acquire.
1. Tactile information refers to the information acquired through sensors in the skin with particular reference to the spatial distribution of pressure, or more generally, tractions, across the contact area.
To handle flexible materials like fabric and paper, we sense the pressure variation across the fingertip. Tactile sensing is also the basis of complex perceptual tasks like medical palpation, where physicians locate hidden anatomical structures and evaluate tissue properties using their hands.
Logitech wingman force feedback mouse:
It is attached to a base that replaces the mouse mat and contains the motors used to provide forces back to the user. Interface used to aid computer users who are blind or visually disabled; or who are tactile/kinesthetic learners, by providing a slight resistance at the edges of windows and buttons so that the user can "feel" the graphical user interface (GUI). This technology can also provide resistance to textures in computer images, which enables computer users to "feel" pictures such as maps and drawings.
Cyber glove:
Cyber glove can sense the position and movement of the fingers and wrist.
The basic cyber glove system includes one cyber glove, its instrumentation unit, a serial cable to connect to your host computer, and an executable version of virtual hand graphic hand model display and calibration software. The cyber glove has a software programmable switch and led on the wristband to permit the system software developer to provide the cyber glove wearer with additional input/output capability. With the appropriate software, it can be used to interact with systems using hand gestures, and when combined with a tracking device to determine the hand's position in space, it can be used to manipulate virtual objects.
Cyber grasp:
The cyber grasp is a full hand force-feedback exoskeleton device, which is worn over the cyber glove. Cyber grasp consists of a lightweight mechanical assembly, or exoskeleton, that fits over a motion capture glove. About 20 flexible semiconductor sensors are sewn into the fabric of the glove measure hand, wrist and finger movement. The sensors send their readings to a computer that displays a virtual hand mimicking the real hand’s flexes, tilts, dips, waves and swivels.
The same program that moves the virtual hand on the screen also directs machinery that exerts palpable forces on the real hand, creating the illusion of touching and grasping.
Conclusion:
Haptic is the future for online computing and e-commerce, it will enhance the shopper experience and help online shopper to feel the merchandise without leave their home. Because of the increasing applications of hap tics, the cost of the hap tic devices will drop in future. This will be one of the major reasons for commercializing hap tics.