activity
20202024
most citedRecursive Least Squares with Variable-Direction Forgetting -- Compensating for the loss of persistency

81 citations · 101 across the 13 of their papers we have counts for

collaborators

18 papers

math.OC2024

Retrospective Cost-based Extremum Seeking Control with Vanishing Perturbation for Online Output Minimization

Juan A. Paredes, Jhon Manuel Portella, Dennis S. Bernstein +1

Extremum seeking control (ESC) constitutes a powerful technique for online optimization with theoretical guarantees for convergence to the neighborhood of the optimizer under well-…

math.OC2024

Adaptive Backstepping Control of a Bicopter in Pure Feedback Form with Dynamic Extension

Jhon Manuel Portella Delgado, Mohammad Mirtaba, Ankit Goel

This paper presents a model-based, adaptive, nonlinear controller for the bicopter stabilization and trajectory-tracking problem. The nonlinear controller is designed using the bac…

math.OC2023

Computing Invariant Zeros of a Linear System Using State-Space Realization

Jhon Manuel Portella Delgado, Ankit Goel

It is well known that zeros and poles of a single-input, single-output system in the transfer function form are the roots of the transfer function's numerator and the denominator p…

math.DS2023

Adaptive Nonlinear Control of a Bicopter with Unknown Dynamics

Jhon Manuel Portella Delgado, Ankit Goel

This paper presents an adaptive, model-based, nonlinear controller for the bicopter trajectory-tracking problem. The nonlinear controller is constructed by dynamically extending th…

eess.SY2023★ 1 cited

Experimental Flight Testing of an Adaptive Autopilot with Parameter Drift Mitigation

Yin Yong Chee, Parham Oveissi, Siyuan Shao +4

This paper modifies an adaptive multicopter autopilot to mitigate instabilities caused by adaptive parameter drift and presents simulation and experimental results to validate the…

math.DS2022★ 2 cited

Euler's Equation via Lagrangian Dynamics with Generalized Coordinates

Dennis S. Bernstein, Ankit Goel, Omran Kouba

Euler's equation relates the change in angular momentum of a rigid body to the applied torque. This paper fills a gap in the literature by using Lagrangian dynamics to derive Euler…

eess.SY2022

A Tutorial on Neural Networks and Gradient-free Training

Turibius Rozario, Arjun Trivedi, Ankit Goel

This paper presents a compact, matrix-based representation of neural networks in a self-contained tutorial fashion. Specifically, we develop neural networks as a composition of sev…

eess.SY2022

Experimental Flight Testing of a Fault-Tolerant Adaptive Autopilot for Fixed-Wing Aircraft

Joonghyun Lee, John Spencer, Siyuan Shao +3

This paper presents an adaptive autopilot for fixed-wing aircraft and compares its performance with a fixed-gain autopilot. The adaptive autopilot is constructed by augmenting the…

eess.SY2022

On the Accuracy of the One-step UKF and the Two-step UKF

Ankit Goel, Dennis S. Bernstein

The most accurate version of the unscented Kalman filter (UKF) involves the construction of two ensembles. To reduce computational cost, however, UKF is often implemented without t…

eess.SY2022

Retrospective Cost Parameter Estimation with Application to Space Weather Modeling

Ankit Goel, Dennis S. Bernstein

This chapter reviews standard parameter-estimation techniques and presents a novel gradient-, ensemble-, adjoint-free data-driven parameter estimation technique in the DDDAS framew…

math.OC2022

Circumventing Unstable Zero Dynamics in Input-Output Linearization of Longitudinal Flight Dynamics

Jhon Manuel Portella Delgado, Ankit Goel

In this paper, we consider the problem of input-output linearization of the longitudinal flight dynamics. In longitudinal flight dynamics, inputs are typically thrust and elevator…

eess.SY2021★ 2 cited

An Adaptive Digital Autopilot for Fixed-Wing Aircraft with Actuator Faults

Joonghyun Lee, John Spencer, Juan Augusto Paredes +3

This paper develops an adaptive digital autopilot for a fixed-wing aircraft and compares its performance with a fixed-gain autopilot. The adaptive digital autopilot is constructed…

eess.SY2021

An Adaptive PID Autotuner for Multicopters with Experimental Results

John Spencer, Joonghyun Lee, Juan Augusto Paredes +2

This paper develops an adaptive PID autotuner for multicopters, and presents simulation and experimental results. The autotuner consists of adaptive digital control laws based on r…

eess.SY2021

Two Modifications of the Unscented Kalman Filter that Specialize to the Kalman Filter for Linear Systems

Ankit Goel, Dennis S. Bernstein

Although the unscented Kalman filter (UKF) is applicable to nonlinear systems, it turns out that, for linear systems, UKF does not specialize to the classical Kalman filter. This s…

eess.SY2020

Experimental Implementation of an Adaptive Digital Autopilot

Ankit Goel, Juan Augusto Paredes, Harshil Dadhaniya +4

This paper develops an adaptive digital autopilot for quadcopters and presents experimental results. The adaptive digital autopilot is constructed by augmenting the PX4 autopilot c…

eess.SY2020★ 15 cited

Adaptive Digital PID Control of a Quadcopter with Unknown Dynamics

Ankit Goel, Abdulazeez Mohammed Salim, Ahmad Ansari +2

This paper develops an adaptive autopilot for quadcopters with unknown dynamics. To do this, the PX4 autopilot architecture is modified so that the feedback and feedforward control…

math.OC2020★ 81 cited

Recursive Least Squares with Variable-Direction Forgetting -- Compensating for the loss of persistency

Ankit Goel, Adam L. Bruce, Dennis S. Bernstein

Learning depends on the ability to acquire and assimilate new information. This ability depends---somewhat counterintuitively---on the ability to forget. In particular, effective f…

math.OC2020

Convergence and Consistency of Recursive Least Squares with Variable-Rate Forgetting

Adam L. Bruce, Ankit Goel, Dennis S. Bernstein

A recursive least squares algorithm with variable rate forgetting (VRF) is derived by minimizing a quadratic cost function.Under persistent excitation and boundedness of the forget…