Solving fractional optimal control problems and costate estimation via a Muntz pseudospectral method
- Department of Mathematics, Isf. C. Islamic Azad University, Isfahan, Iran.
Received: 09-07-2025
Revised: 05-08-2025
Accepted: 07-08-2025
Published in Issue 10-08-2025
Copyright (c) 2025 Mohammad Maleki, Hussein Ghassemi (Author)

This work is licensed under a Creative Commons Attribution 4.0 International License.
How to Cite
Abstract
In this paper, we first introduce the Muntz–Legendre polynomials and establish their relation to Jacobi polynomials. Then, a stable scheme is presented for approximating the Caputo fractional derivative of the Muntz–Legendre polynomials. Next, we introduce a Muntz–polynomial pseudospectral method with fractional power of Legendre–Gauss–
Radau mesh points for solving fractional optimal control problems. This method is particularly suitable for problems whose solutions contain non-integer exponent factors. We also construct a novel costate estimation procedure based on the first order optimality conditions and the structure of the underlying problem. Three numerical examples, including a fractional model for tumor burden under immune suppression, are presented to demonstrate the applicability and spectral accuracy of the proposed method.
Keywords
- Fractional optimal control; Pseudospectral; Costate estimation; M¨untz polynomials; Fractional cancer model
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10.57647/ijm2c.2025.150423