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Rajni V. Patel

18 accepted papers

2025

Deep Koopman Approach for Nonlinear Dynamics and Control of Tendon-Driven Continuum Robots

RA-L 2025

Tendon-driven continuum robots (TDCRs) have received widespread attention in the medical domain due to their slender shape and flexibility. Modeling the dynamics of TDCRs involves continuum mechanics that result in nonlinear and computationally intensive models posing challenges for real-time contro

Cited by 7SourceScholar
2025

Image-Guided Surgical Planning for Percutaneous Nephrolithotomy Using CTRs: A Phantom-Based Study

ICRA 2025

In this paper, we validate the effectiveness of the optimal planning algorithms we have developed for devising surgical plans for Percutaneous Nephrolithotomy (PCNL) using patient-specific Concentric-Tube Robots (CTRs). To do so, we built a life-sized phantom model of the right hemithorax, replicati

Cited by 0SourceScholar
2023

Design Optimization and Data-driven Shallow Learning for Dynamic Modeling of a Smart Segmented Electroadhesive Clutch

ICRA 2023poster

Electroadhesive clutches have attracted a great deal of interest in the last decade as semi-active actuators for human-robot interaction due to their lightweight, low power consumption, and tunable high-torque output capability. However, because of the complexity of their dynamics, in most cases, th…

Cited by 0SourceScholar
2021

Time-Domain Passivity-based Controller with an Optimal Two-channel Lawrence Telerobotic Architecture

ICRA 2021poster

The time-domain passivity approach has been proposed in the literature in a variety of formats to guarantee the stability of teleoperation leader-follower systems. The conventional use of the proposed technique utilizes the control effort at the follower side as the force feedback to be sent back to…

Cited by 3SourceScholar
2019

Design and Implementation of a Two-DOF Robotic System with an Adjustable Force Limiting Mechanism for Ankle Rehabilitation

ICRA 2019poster

This paper presents a novel light-weight back-drivable inherently-safe robotic mechanism for delivering ankle rehabilitation therapies. The robot is designed to be used as the ankle module of a multi-purpose lower-limb rehabilitation robot. A novel friction-based safety feature has been introduced t…

Cited by 3SourceScholar
2019

HMFP-DBRNN: Real-Time Hand Motion Filtering and Prediction via Deep Bidirectional RNN

RA-L 2019

Pathological hand tremor (PHT) is among the most common movement symptoms of several neurological disorders including Parkinson's disease and essential tremor. Extracting PHT is of paramount importance in several engineering and clinical applications such as assistive and robotic rehabilitation tech

Cited by 18SourceScholar
2018

Multiple-Model and Reduced-Order Kalman Filtering for Pathological Hand Tremor Extraction

ICASSP 2018accepted

Tremor extraction techniques are considered as the central component of several rehabilitative and compensatory robotic technologies, and the accuracy of such filters can directly affect the performance of the aforementioned technologies. Motivated by this fact, the paper proposes an adaptive estima…

Cited by 0SourceScholar
2017

A motion transmission model for multi-DOF tendon-driven mechanisms with hysteresis and coupling: Application to a da Vinci® instrument

IROS 2017poster

Tendon-driven mechanisms used in robotic surgery exhibit strong nonlinearities, particularly a static backlash-like hysteresis, in their motion transmission behavior. In this paper, an extension of a previously developed model is proposed that allows for estimation of angular displacements in multi-…

Cited by 5SourceScholar
2017

Development of an optical fiber-based sensor for grasping and axial force sensing

ICRA 2017poster

In spite of the remarkable benefits that minimally invasive surgery provides for patients, the absence of force feedback is still a significant disadvantage. Several studies have been performed to address this issue; however, an accurate sterilizable force sensing technology for measuring axial and…

Cited by 33SourceScholar
2016

Curvature, Torsion, and Force Sensing in Continuum Robots Using Helically Wrapped FBG Sensors

RA-L 2016

Due to their small size and flexibility, fiber Bragg grating (FBG) sensors have been integrated into needle-sized continuum robots for shape estimation and force measurement. The challenge in extending previous shape and force sensing technologies to pre-curved continuum robots, such as concentric-t

Cited by 224SourceScholar
2015

A multi-sensory mechatronic device for localizing tumors in minimally invasive interventions

ICRA 2015poster

Tumor localization in traditional lung resection surgery requires manual palpation of the deflated lung through a thoracotomy. It is a painful procedure that is not suitable for many patients. Therefore, a multisensory mechatronic device was designed to localize tumors using a minimally invasive app…

Cited by 15SourceScholar
2015

A new passivity-based control technique for safe patient-robot interaction in haptics-enabled rehabilitation systems

IROS 2015poster

In this paper, a new passivity-based technique is proposed to analyze and guarantee the stability of haptics-enabled telerobotic rehabilitation systems where there is a possibility of having more sources of non-passivity than communication delays. In practice, the difficulty of therapeutic exercises…

Cited by 23SourceScholar
2015

A robotics-assisted catheter manipulation system for cardiac ablation with real-time force estimation

IROS 2015poster

Lack of dexterous control over the position of a catheter's distal tip and not having any feedback from the quality of tip - tissue contact are among the factors that make the conventional catheter-based method of performing cardiac ablation very challenging. To resolve these issues, in this paper,…

Cited by 15SourceScholar
2015

Articulating minimally invasive ultrasonic tool for robotics-assisted surgery

ICRA 2015poster

In this paper, a robotics-assisted articulating ultrasonic surgical scalpel for minimally invasive soft tissue cutting and coagulation is designed and developed. For this purpose, the optimal design of a Langevin transducer with stepped horn profile is presented for internal-body applications. The m…

Cited by 6SourceScholar
2015

Magneto-Rheological actuators for haptic devices: Design, modeling, control, and validation of a prototype clutch

ICRA 2015poster

In our previous work [1], the potential benefits of Magneto-Rheological Fluid based actuators to the field of haptics were studied. Our results showed that the superior mechanical attributes of such actuators contribute to improvement of stability and transparency in haptic devices. To this end, a n…

Cited by 14SourceScholar
2015

Performance evaluation of Magneto-Rheological based actuation for haptic feedback in medical applications

IROS 2015poster

This paper reports on the performance evaluation of Magneto-Rheological Fluid (MRF) based actuation systems when used in haptic interfaces. MRF-based actuators exhibit superior characteristics, which can significantly contribute to the transparency and stability of haptic devices. To validate this s…

Cited by 5SourceScholar
2015

Therapist-in-the-Loop robotics-assisted mirror rehabilitation therapy: An Assist-as-Needed framework

ICRA 2015poster

This paper presents a Therapist-in-the-Loop (TIL) framework for robotics-assisted mirror rehabilitation therapy integrated with adaptive Assist-as-Needed (ANN) training, to be adjusted based on the impairment and disability level of the patient's affected limb. Closed-loop system stability has been…

Cited by 10SourceScholar