Abstract

In order to assess the capabilities of South Africa as a launch site for commercial satellites, an optimal control solver was developed. The developed solver makes use of direct Hermite-Simpson collocation methods, and can be applied to a general optimal control problem. Analytical first derivative information was obtained for direct Hermite-Simpson collocation methods. Typically, a numerical estimate of the derivative information is used. This paper will present the solver algorithm, and the formulation and derivation of the analytical first derivative information for this approach. A sample problem is provided as validation of the solver.

Highlights

  • An optimal control solver making use of the direct Hermite-Simpson collocation formulation of optimal control problems was developed

  • The formulae obtained can be extended to solving ordinary two-point boundary value problems with HermiteSimpson collocation

  • These first derivatives are estimated using sparse finite-differencing, alternatively they can be obtained with automatic differentiation or symbolic differentiation

Read more

Summary

Introduction

An optimal control solver making use of the direct Hermite-Simpson collocation formulation of optimal control problems was developed. Formulae for determining the analytical first derivative information of the defect constraints of the direct Hermite-Simpson collocation formulation of optimal control problems have been formulated. The formulae obtained can be extended to solving ordinary two-point boundary value problems with HermiteSimpson collocation These first derivatives are estimated using sparse finite-differencing, alternatively they can be obtained with automatic differentiation or symbolic differentiation. Optimal control is a field of study with various application in fields such as aerospace, robotics and chemical engineering It is concerned with the determination of trajectories which optimise some cost function of a given dynamic system. This paper first outlines the general transcription process of an optimal control problem to an Nonlinear Programming (NLP) problem using Hermite-Simpson collocation with linear mean control splines. Following which the first derivatives will be applied with example problems, using Matlab’s Sequential Quadratic Programming (SQP) algorithm

Transcription
Warm Starts
Choice of Non-Linear Programming
First Derivative Information
Interpolation of Solution and Error Estimation
Linear case
Nonlinear case
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.