Amit Bhardwaj

Indian Institute of Technology Jodhpur | IITJ · Electrical Engineering Programme

Data-driven modeling and rendering is a general approach in haptics aiming to provide highly accurate haptic perceptual experiences simulating complex real physical dynamics, such as deformable or textured objects. A prevalent problem in the present methods for data-driven haptics is that the computational cost for modeling grows rapidly, even beco...

In the recent past, data-driven approaches have gained importance for modeling and rendering of haptic properties of deformable objects. In this paper, we propose a new data-driven approach based on a well known machine learning technique: random forest. We train the random forest for regression for estimating the input-output mapping between discr...

In this paper, we propose a new data-driven approach for haptic modeling of normal interactions on homogeneous viscoelastic deformable objects. The approach is based on a well-known machine learning technique: random forest. Here we employ random forest for regression. We acquire discrete-time interaction data for many automated cyclic compressions...

The IEEE "Tactile Internet" (TI) Standards working group (WG), designated the numbering IEEE 1918.1, undertakes pioneering work on the development of standards for the TI. This paper describes the WG, its intentions, and its developing baseline standard and the associated reasoning behind that and touches on a further standard already initiated und...

This paper presents a method that automatically transforms a virtual environment (VE) according to the mood of input music. We use machine learning to extract a mood from the music. We then select images exhibiting the mood and transfer their styles to the textures of objects in the VE photorealistically or artistically. Our user study results indi...

The Tactile Internet will enable users to physically explore remote environments and to make their skills available across distances. An important technological aspect in this context is the acquisition, compression, transmission, and display of haptic information. In this paper, we present the fundamentals and state of the art in haptic codec desi...

Media technology, in particular video recording and playback, keeps improving to provide users with high-quality real and virtual visual content. In recent years, increasing the temporal sampling rate of videos and the refresh rate of displays has become one focus of technical innovation. This raises the question, how high the sampling and refresh...

In this chapter, we extend the findings of Chap. 3 to 2-D kinesthetic data. For this, we again design an appropriate experimental setup and record the responses of several users to piecewise constant haptic signals. In order to predict the labels of the responses, we have used the Weber, level crossing, and conic section-based classifiers. It has b...

In this chapter, we study whether the perceptual deadzone depends on the task to be performed during the psychophysical experiments. In order to study this, we design a psychophysical experiment where we define two specific tasks: discriminative and comparative. In the discriminative task, the user must discriminate if the successive stimulus is di...

In this chapter, we study various possible structures of perceptually adaptive sampling strategies for one-dimensional haptic signal. For that purpose, an experimental setup is designed where we record haptic responses extensively for several users. The responses are labeled as perceived (+1) or non-perceived (\(-1\)). After that, various classifie...

In this chapter, we first review the current literature related to the haptic data compression techniques. Subsequently, we review the concept of using perceptual deadzone for data compression. We review perceptually adaptive sampling strategies and their corresponding deadzones for multidimensional haptic signals. After that the literature related...

In the literature on psychophysics, it is reported that during a psychophysical experiment when a user is subjected to many trials in succession, the perception of the current trial is observed to be overly similar to the previous trial (assimilation effect), and is observed to be dissimilar to distantly past trials (contrast effect). Overall, this...

In the literature, it has been assumed that the Weber fraction is always fixed for an individual and is independent of any temporal variation in the stimulus. If the assumption is not correct, the perceptual limitations of a human being are not fully exploited by the fixed Weber fraction. For example, if the signal changes very slowly, it is diffic...

If the time spacing between two consecutive, perceptually significant kinesthetic force stimuli is less than the minimum time spacing (temporal resolution \(T_r\)) required in perceiving the jump discontinuity, then the second force stimulus will not be perceived even if it is well above the just noticeable difference. Hence, there is no need to tr...

This book focuses on the study of possible adaptive sampling mechanisms for haptic data compression aimed at applications like tele-operations and tele-surgery. Demonstrating that the selection of the perceptual dead zones is a non-trivial problem, it presents an exposition of various issues that researchers must consider while designing compressio...

Perceptually adaptive sampling based on Weber's law has been used to reduce the haptic packet rate for efficient haptic data transmission over Internet. In a teleoperation, perceptually significant force samples are transmitted from a robot to a human operator. If the time spacing between two consecutive perceptually sampled kinesthetic force stimu...

In all prior applications, it is assumed that the just noticeable difference (JND) for the kinesthetic force stimulus is independent of rate of change of the stimulus. In this work, we study how the JND is affected over the rate of change of the stimulus. This study has a possible application in better design of a haptic data compression algorithm....

In this paper, we perform a data driven analysis of human perception of 2 D haptic data, and study possible structures of the perceptual deadzone. We describe an experimental set up where a user is subjected to a 2 D piecewise constant haptic force, and is asked to respond with a click whenever he/she feels any change in the stimuli. The jumps of t...

In this article, we identify adaptive sampling strategies for haptic signals. Our approach relies on experiments wherein we record the response of several users to haptic stimuli. We then learn different classifiers to predict the user response based on a variety of causal signal features. The classifiers that have good prediction accuracy serve as...

In applications such as telesurgery, it is required to transmit haptic signals to a remote location with a delay of at most few milliseconds. To reduce the packet rate and yet retain perceptual quality, adaptive sampling has been explored in the literature. In particular, in earlier work we proposed and analyzed an adaptive sampling scheme based on...