Qualification: 
M.Tech, B-Tech
amrithas@am.amrita.edu

Amritha S. currently serves as Assistant Professor (Sr. Gr.) at the Department of Electrical and Electronics Engineering at Amrita School of Engineering, Amritapuri. Amritha has completed B. Tech. in EEE from T. K. M. Engineering college in the year 2009 and M. Tech. in Guidance and Navigational Control from College of Engineering, Trivandrum in the year 2011. She is currently pursuing PhD.

Publications

Publication Type: Conference Paper

Year of Publication Title

2018

S. Mohan, J., N., and Amritha S., “Coupled Dynamic Control of Unicycle Robot Using Integral Linear Quadratic Regulator and Sliding Mode Controller”, in Materials Today: Proceedings, 2018, vol. 5, pp. 1447-1454.[Abstract]


Unicycle robot is a non-linear, unbalance system that has the less number of point contact to the ground, therefore it is a best platform for researchers to study balance control and motion. This paper focuses on the dynamic modeling and control of unicycle robot. A coupled nonlinear system dynamics is considered for the controller design. Two different controllers are proposed –integral LQR for pitch dynamics and integral sliding mode for roll dynamics. Simulations performed on MATLAB/SIMULINK platform proved the effectiveness of the proposed controllers.

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2017

S. Sandhra, Amritha S., and Karuppasamy, D. Ilango, “Slosh container system: Comparitive study of linear and non-linear sliding surfaces in sliding mode controller for slosh free motion”, in 2017 International Conference on Intelligent Computing, Instrumentation and Control Technologies (ICICICT), 2017.[Abstract]


Liquid sloshing has been a challenging problem in different fields including launch vehicles and long range missiles applications. The coupled-slosh vehicle dynamics constitutes a highly non-linear second order under actuated system. The system is highly non-linear system, therefore controlling of slosh is highly complex. This paper presents a novel way of designing a Sliding Mode Controller (SMC) using non-linear sliding surface is used for slosh control in a container. Modeling of slosh dynamics is highly complex and nonlinear, the most commonly used equivalent mechanical model for lateral slosh dynamics is simple pendulum model. For linearizing the system, Partial Feedback Linearization technique has been used. In various literature SMC has been used as controller, the main issue of using SMC is chattering effect. For reducing the chattering effect in the control efforts the Boundary Layer Design technique is developed. Hence the proposed controller will provide better closed loop performance compared with conventional SMC (SMC with linear sliding surface). The proposed system is modeled and simulated using Matlab/Simulink to prove the effectiveness of SMC with nonlinear sliding surface compared with linear sliding surface.

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2017

Prathibha S. Babu and Amritha S., “Control of Ball-screw Drive Systems”, in 2017 International Conference on Intelligent Computing, Instrumentation and Control Technologies (ICICICT), 2017.

2017

P. Chandran, A. Vivek, and Amritha S., “Optimisation of overhead crane”, in 2017 International Conference on Circuit ,Power and Computing Technologies (ICCPCT), Kollam, India, 2017.[Abstract]


Overhead cranes are commonly used in industries for the displacement of materials. Overhead cranes are modelled. Various trajectories are generated based on the open loop scheme. So, optimal control models have been proposed including energy, swing and transportation time. For optimization SQP is used as the optimization technique. It includes objective function for energy, swing and transportation time. Various constraints need to be satisfied. Constraints include both equality and inequality constraints. Multi objective optimization is being performed for optimizing both time and energy at the same time. Genetic algorithm is performed. It is a biologically inspired process. Pareto front is obtained which shows the trade offs between energy and time. By taking slope of energy time graph acceleration is obtained which is fed as reference input to a PID controller and is controlled. The simulations obtained are given in detail.

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2011

Amritha S., Benjamin.R, G. Ernestins, and , “Reentry Guidance for Reusable Launch Vehicle Using Nonlinear Tracking”, in 12th National Conference on Technological Trends, 2011.

Publication Type: Conference Proceedings

Year of Publication Title

2016

Nandagopal J. L., Amritha S., and Mohan, S., “Coupled dynamic control of unicycle robot using integral LQR and sliding mode controller”, International Conference on Proceedings of Materials, Minerals and Energy, PMME 2016. 2016.[Abstract]


Unicycle robot is a non-linear, unbalance system that has the less number of point contact to the ground, therefore it is a best platform for researchers to study balance control and motion. This paper focuses on the dynamic modeling and control of unicycle robot. A coupled nonlinear system dynamics is considered for the controller design. Two different controllers are proposed – integral LQR for pitch dynamics and integral sliding mode for roll dynamics. Simulations performed on MATLAB/SIMULINK platform proved the effectiveness of the proposed controllers.

More »»

Publication Type: Journal Article

Year of Publication Title

2016

S. Mohan, Nandagopal J. L., and Amritha S., “Decoupled Dynamic Control of Unicycle Robot Using Integral Linear Quadratic Regulator and Sliding Mode Controller ”, Journal of Proceedia Technology, vol. 26, 2016.[Abstract]


Unicycle robot is a non-holonomic, non-linear, static unbalance system that has the minimal number of point contact to the ground, therefore it is a perfect platform for researchers to study motion and balance control. This paper focuses on the dynamic modeling of unicycle robot. Two concepts used for modeling unicycle robot are: reaction wheel pendulum and inverted pendulum. The pitch axis is modeled as inverted pendulum and roll axis is modeled as reaction wheel pendulum. The unicycle yaw dynamics is not considered which makes derivation of dynamics relatively simple. For the roll controller, sliding-mode controller has been adopted and optimal methods are used to minimize switching-function chattering. For pitch controller, a Linear Quadratic Regulator controller has been implemented to drive the unicycle robot to follow the desired velocity trajectory. More »»

2013

A. Atheena and Amritha S., “Matrix Converter based Unified Power flow Converters(UPFC),”, Proceedings of National Conference on Technological Advancements in Power and Energy, 2013.