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Manivannan Muniyandi

Bio: Manivannan Muniyandi is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Computer science & Haptic technology. The author has an hindex of 7, co-authored 16 publications receiving 587 citations. Previous affiliations of Manivannan Muniyandi include Massachusetts Institute of Technology.

Papers
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Journal ArticleDOI
TL;DR: This work discusses important aspects of haptics in MISST, such as haptic rendering and haptic recording and playback, and discusses the importance of net forces resulting from tool-tissue interactions in surgery.
Abstract: Haptics is a valuable tool in minimally invasive surgical simulation and training. We discuss important aspects of haptics in MISST, such as haptic rendering and haptic recording and playback. Minimally invasive surgery has revolutionized many surgical procedures over the last few decades. MIS is performed using a small video camera, a video display, and a few customized surgical tools. In procedures such as gall bladder removal (laparoscopic cholesystectomy), surgeons insert a camera and long slender tools into the abdomen through small skin incisions to explore the internal cavity and manipulate organs from outside the body as they view their actions on a video display. Because the development of minimally invasive techniques has reduced the sense of touch compared to open surgery, surgeons must rely more on the feeling of net forces resulting from tool-tissue interactions and need more training to successfully operate on patients.

373 citations

Journal ArticleDOI
01 Jul 2004
TL;DR: Using the technology described in this paper, transatlantic touch was successfully demonstrated between the Touch Lab at Massachusetts Institute of Technology, USA and Virtual Environments and Computer Graphics (VECG) lab at University College London (UCL), UK in 2002.
Abstract: The extent to which the addition of haptic communication between human users in a stared virtual environment (SVE) contributes to the shared experience of the users has not received much attention in the literature, In this paper we describe a demonstration of and an expenmental study on haptic interaction between two users over a network of significant physical distance and a number of Network hops. A number of techniques to mitigate instability of the haptic interactions induced by network latency are presented An experiment to evaluate the use of haptics in a coilborative situation mediated by a networked virtual environment is examined The experimental subjects were to cooperate in lifting a virtual box together under one of four conditions in a between-groups design. Questionnaires were used to report the ease with which they could perform the task and the subjective levels of presence ants copresence experienced This extends earlier work by the authors to consider the possibility of haptic collaboration under real network conditions with a Number of improvements. Using the technology described in-this paper, transatlantic touch was successfully demonstrated between the Touch lab at Massachusetts Instatute of Technology, USA and Virtual Environments and Computer Graphics (VECG) lab at University Collegc London (UCL), UK in 2000, It as also presented at the Internet II demonstration meeting in 2002 between University of Southern California and the Massachusetts Instrtute of Technology.

140 citations

Journal ArticleDOI
TL;DR: Breath rate variability (BRV) as an alternate measure of meditation even over a short duration is proposed and can provide short-term effect on anatomic nervous system meditation, while HRV shows long-term effects.
Abstract: Context: Reliable quantitative measure of meditation is still elusive. Although electroencephalogram (EEG) and heart rate variability (HRV) are known as quantitative measures of meditation, effects of meditation on EEG and HRV may well take long time as these measures are involuntarily controlled. Effect of mediation on respiration is well known; however, quantitative measures of respiration during meditation have not been studied. Aims: Breath rate variability (BRV) as an alternate measure of meditation even over a short duration is proposed. The main objective of this study is to test the hypothesis that BRV is a simple measure that differentiates between meditators and nonmeditators. Settings and Design: This was a nonrandomized, controlled trial. Volunteers meditate in their natural habitat during signal acquisition. Subjects and Methods: We used Photo-Plythysmo-Gram (PPG) signal acquisition system from BIO-PAC and recorded video of chest and abdomen movement due to respiration during a short meditation (15 min) session for 12 individuals (all males) meditating in a relaxed sitting posture. Seven of the 12 individuals had substantial experience in meditation, while others are controls without any experience in meditation. Respiratory signal from PPG signal was derived and matched with that of the video respiratory signal. This derived respiratory signal is used for calculating BRV parameters in time, frequency, nonlinear, and time-frequency domain. Statistical Analysis Used: First, breath-to-breath interval (BBI) was calculated from the respiration signal, then time domain parameters such as standard deviation of BBI (SDBB), root mean square value of SDBB (RMSSD), and standard deviation of SDBB (SDSD) were calculated. We performed spectral analysis to calculate frequency domain parameters (power spectral density [PSD], power of each band, peak frequency of each band, and normalized frequency) using Burg, Welch, and Lomb–Scargle (LS) method. We calculated nonlinear parameters (sample entropy, approximate entropy, Poincare plot, and Renyi entropy). We calculated time frequency parameters (global PSD, low frequency-high frequency [LF-HF] ratio, and LF-HF power) by Burg LS and wavelet method. Results: The results show that the mediated individuals have high value of SDSD (+24%), SDBB (+29%), and RMSSD (+26%). Frequency domain analysis shows substantial increment in LFHF power (+73%) and LFHF ratio (+33%). Nonlinear parameters such as SD1 and SD2 were also more (>20%) for meditated persons. Conclusions: As compared to HRV, BRV can provide short-term effect on anatomic nervous system meditation, while HRV shows long-term effects. Improved autonomic function is one of the long-term effects of meditation in which an increase in parasympathetic activity and decrease in sympathetic dominance are observed. In future works, BRV could also be used for measuring stress.

36 citations

Book ChapterDOI
10 Jun 2008
TL;DR: A configuration of the H-bridge is employed which can cause physically dissipative damping to impart stability to the haptic device, which results in an increase in passive wall stiffness over the performance of an undamped DC motor.
Abstract: Physically dissipative damping can increase the range of passive stiffness that can be rendered by a haptic device. Unlike simulated damping it does not introduce noise into the haptic control system. A DC motor can generate such damping if it's terminals are shorted. We employ a configuration of the H-bridge which can cause this damping to impart stability to our haptic device. This results in an increase in passive wall stiffness of about 33.3% at a sampling rate of 100Hz and 16.6% at 1kHz over the performance of an undamped DC motor. We have also attempted to implement the system on the hybrid haptic control system [1], it was seen that a perceivable change in the performance of this system was not observed by the use of DC motor damping.

20 citations

Journal Article
TL;DR: This paper proposes a method for rendering X-ray images in real-time on a PC with consumer level graphics hardware, while improving the quality of the images.
Abstract: The ability to simulate realistic fluoroscopic images in real-time is a key aspect of any interventional radiology training system. In this paper, we propose a method for rendering X-ray images in real-time on a PC with consumer level graphics hardware, while improving the quality of the images. Although volume rendering techniques form the basis of our algorithm, we studied the characteristics of actual X-ray images to develop a method that can provide a new level of realism. In addition, the integration of the various levels of information contained in a CT scan in the rendering pipeline can be exploited to produce even more realistic, patient-specific X-ray or fluoroscopic images. Although the results presented here are preliminary, the performance of multi-texturing and multi-stage rasterization features available on recent low-cost graphics hardware already allows us to render X-ray images at about 30 frames per second.

18 citations


Cited by
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Journal ArticleDOI
06 Jun 1986-JAMA
TL;DR: The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or her own research.
Abstract: I have developed "tennis elbow" from lugging this book around the past four weeks, but it is worth the pain, the effort, and the aspirin. It is also worth the (relatively speaking) bargain price. Including appendixes, this book contains 894 pages of text. The entire panorama of the neural sciences is surveyed and examined, and it is comprehensive in its scope, from genomes to social behaviors. The editors explicitly state that the book is designed as "an introductory text for students of biology, behavior, and medicine," but it is hard to imagine any audience, interested in any fragment of neuroscience at any level of sophistication, that would not enjoy this book. The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or

7,563 citations

Journal ArticleDOI
14 Oct 2003
TL;DR: A broad overview of medical robot systems used in surgery, including basic concepts of computer-integrated surgery, surgical CAD/CAM, and surgical assistants, and some of the major design issues particular to medical robots is provided.
Abstract: This paper provides a broad overview of medical robot systems used in surgery. After introducing basic concepts of computer-integrated surgery, surgical CAD/CAM, and surgical assistants, it discusses some of the major design issues particular to medical robots. It then illustrates these issues and the broader themes introduced earlier with examples of current surgical CAD/CAM and surgical assistant systems. Finally, it provides a brief synopsis of current research challenges and closes with a few thoughts on the research/industry/clinician teamwork that is essential for progress in the field.

1,015 citations

Journal ArticleDOI
TL;DR: The designs of existing commercial RMIS systems are not conducive for force feedback, and creative solutions are needed to create compelling tactile feedback systems.
Abstract: Purpose of Review Robot-assisted minimally invasive surgery (RMIS) holds great promise for improving the accuracy and dexterity of a surgeon while minimizing trauma to the patient. However, widespread clinical success with RMIS has been marginal. It is hypothesized that the lack of haptic (force and tactile) feedback presented to the surgeon is a limiting factor. This review explains the technical challenges of creating haptic feedback for robot-assisted surgery and provides recent results that evaluate the effectiveness of haptic feedback in mock surgical tasks.

551 citations

Journal ArticleDOI
TL;DR: Results indicate that haptic feedback is important during the early phase of psychomotor skill acquisition in virtual reality training, but results seem promising in the area of robot-assisted endoscopic surgical training.
Abstract: Background Virtual reality (VR) as surgical training tool has become a state-of-the-art technique in training and teaching skills for minimally invasive surgery (MIS). Although intuitively appealing, the true benefits of haptic (VR training) platforms are unknown. Many questions about haptic feedback in the different areas of surgical skills (training) need to be answered before adding costly haptic feedback in VR simulation for MIS training. This study was designed to review the current status and value of haptic feedback in conventional and robot-assisted MIS and training by using virtual reality simulation.

469 citations