Jayant Kumar Mohanta

Bio: Jayant Kumar Mohanta is an academic researcher from Indian Institute of Technology Indore. The author has contributed to research in topics: Parallel manipulator & Motion control. The author has an hindex of 4, co-authored 17 publications receiving 109 citations. Previous affiliations of Jayant Kumar Mohanta include Indian Institutes of Technology & Indian Institute of Technology Kanpur.

Inverse dynamics and control of a 3-DOF planar parallel (U-shaped 3-PPR) manipulator

Abstract: This paper addresses the inverse dynamics of three degrees of freedom (DOF) U-shaped planar parallel manipulator having three legs consisting of prismatic-prismatic-revolute (PPR) joint arrangement in which each leg has one active prismatic joint. This paper also proposes a proportional-derivative (PD) like adaptive sliding mode control combined with a disturbance observer for the motion control of the proposed manipulator. Using this control scheme, the controlled robotic manipulator is transformed into decoupled dynamics, and thus the motion performance is very convenient to quantify. Based on Lyapunov like argument the global asymptotic stability of the proposed closed loop system is proved. Real time experiments performed on the in-house fabricated prototype of the proposed manipulator are provided to substantiate the effectiveness and the improved performance of the proposed controller. The proposed controller performances are also compared with traditional controllers such as proportional integral derivative (PID) controller, sliding mode controller (SMC) and computed torque controller (CTC) Inverse dynamics of a 3-DOF planar parallel robot (3-PPR) is presented.A robust tracking controller with disturbance compensation has been introduced.Effectiveness of the controller has been demonstrated with prototype experiments.A comparative study of the proposed and existing controllers has been performed.

Design and Robust Motion Control of a Planar 1P-2P RP Hybrid Manipulator for Lower Limb Rehabilitation Applications

Abstract: This paper addresses a robust motion control design of a planar 1P-2P RP hybrid manipulator for performing the lower limb rehabilitation treatments. The effectiveness and performances of the proposed system along with the motion control scheme is demonstrated using the real-time experiments. Further the robustness and sensitivity of the proposed control scheme is analyzed under different working conditions. In addition, the applicability of the proposed system is demonstrated successfully on an in-house fabricated prototype as a continuous passive sitting type lower limb rehabilitation mechanism in terms of clinical gait pattern generation and the gait-tracking task.

Dual Integral Sliding Mode Control Loop for Mechanical Error Correction in Trajectory-Tracking of a Planar 3-PRP Parallel Manipulator

Abstract: This paper presents a dual-loop control scheme based on an integral sliding mode control scheme for the task-space pose error correction in trajectory-tracking of a planar 3-PRP parallel manipulator due to mechanical inaccuracies. The proposed dual-loop control scheme uses redundant sensor feedback, i.e., individual active joint displacements, velocities (at the joint-space level) and, end-effector positions and orientation (at the task-space level) are obtained as feedback signals using appropriate sensors. Using the redundant feedback information, the actual pose errors of the end-effector are computed in the outer-loop (kinematic) control and rectified in joint-space inner-loop (dynamic) control to achieve the given desired task-space trajectory. To demonstrate the efficacy and show complete performance of the controllers, real-time experiments are executed on an in-house fabricated planar 3-PRP parallel manipulator. The experimentation results show that the manipulator tracing performance is considerably improved with the proposed dual-loop control scheme. In addition, the controller parameter sensitivity and robustness analyses are also accomplished.

A Survey of Robots in Healthcare

Abstract: In recent years, with the current advancements in Robotics and Artificial Intelligence (AI), robots have the potential to support the field of healthcare. Robotic systems are often introduced in the care of the elderly, children, and persons with disabilities, in hospitals, in rehabilitation and walking assistance, and other healthcare situations. In this survey paper, the recent advances in robotic technology applied in the healthcare domain are discussed. The paper provides detailed information about state-of-the-art research in care, hospital, assistive, rehabilitation, and walking assisting robots. The paper also discusses the open challenges healthcare robots face to be integrated into our society.

Development of Active Lower Limb Robotic-Based Orthosis and Exoskeleton Devices: A Systematic Review

Abstract: The basic routine movements for elderly people are not easily accessible due to the weak muscles and impaired nerves in their lower extremity In the last few years, many robotic-based rehabilitation devices, like orthosis and exoskeletons, have been designed and developed by researchers to provide locomotion assistance to support gait behavior and to perform daily activities for elderly people However, there is still a need for improvement in the design, actuation and control of these devices for making them cost-effective in the worldwide market In this work, a systematic review is presented on available lower limb orthosis and exoskeleton devices, to date The devices are broadly reviewed according to joint types, actuation modes and control strategies Furthermore, tabular comparisons have also been presented with the types and applications of these devices Finally, the needful improvements for realizing the efficacy of lower limb rehabilitation devices are discussed along with the development stage This review will help the designers and researchers to develop an efficient robotic device for the rehabilitation of the lower limb

Real-time smooth trajectory generation for nonholonomic mobile robots using Bézier curves

Abstract: This paper focuses on generating smooth trajectories for a wheeled nonholonomic mobile robot using piecewise Bezier curves with properties ideally suited for this purpose. The developed algorithm generates smooth motion trajectories with C2 continuous curvature. We consider a teleoperated wheeled mobile robot in an indoor environment with ceiling cameras for operator visibility. The motion trajectory is constrained by the operator-specified via points and path width. A method to automatically generate a trajectory based on only these two inputs is proposed and demonstrated. To improve the trackability of the mobile robot, we adopted a Bezier subdivision method and inserted a quintic Bezier segment into high-curvature areas. The proposed algorithm can be used for real-time obstacle-avoidance trajectory generation because it allows trajectory subdivision and arbitrarily setting of the second derivative at the start point. Simulation and experimental results demonstrate the effectiveness of the proposed method. HighlightsNew algorithm to generate smooth trajectories for a wheeled mobile robot.Trajectory generation satisfying operator-specified via points and path width.Trackability enhancement to high-curvature trajectory by Bezier subdivision method.Design of a trajectory tracking controller based on the Lyapunov stability theorem.

Inverse kinematics for a novel hybrid parallelserial five-axis machine tool

Abstract: A unique successful postprocessor for a hybrid parallel-serial machine tool is developed.Smart machining must be accomplished without forcing the tool to make sharp turns when HSM controls detect a turn approaching.NC codes are recalculated to form a new path for the pivot that can avoid the discretization near the singularity points in this study.The novelty of the paper is successfully to propose a new hybrid parallel-serial five-axis machining model.The manufacturers that are interested in integrating the inverse kinematics into the design process of their hybrid product. Instead of obsessively emphasizing to interpolate more points from the linearization algorithm, the NC codes are recalculated to form a new path for the pivot that can avoid the discretization near the singularity points in this study. In previous studies, orientable-spindle machines were directly used to generate smooth tool paths traversing singular positions through inverse kinematics. In many characteristics and practices, PKMs (parallel kinematic machines) and serial machines are the opposites of each other. Fully PKMs have relatively very limited working-space, especially in terms of orientation characteristics. Fully serial machines have a problem of error accumulation. This paper presents a modular method to construct a postprocessor system for a novel hybrid parallel-serial five-axis machine tool. A hybrid parallel-serial mathematical model is introduced to analyze a structural configuration. The configuration decomposition of machine tools is used to create the kernel of the postprocessor. The proposed modified DenavitHartenberg notation is used in the coordinate conversion procedure, and then an algorithm is used for developing the inverse kinematics of five-axis machines. The feasibility of solutions depends on the surface normal along the tool path satisfying certain orientation constraints. The proposed algorithm can be easily adapted to convert between cutter contact path and cutter location code and implemented on computer-aided design and computer-aided manufacturing systems. Examples with end-milling and side-milling tools are demonstrated and real cutting parts are implemented for verifying the algorithm.