Christian Hofmann

Politecnico di Milano | Polimi · Department of Aerospace Engineering

Different discretization and trust-region methods are compared for the low-thrust fuel-optimal trajectory optimization problem using successive convex programming. In particular, the differential and integral formulations of the adaptive pseudospectral Legendre–Gauss–Radau method, an arbitrary-order Legendre–Gauss–Lobatto technique based on Hermite...

A framework is presented where a nonlinear dynamical system is transformed into a higher-dimensional bilinear system using the Koopman operator theory. The nonlinear dynamics are projected onto a set of orthogonal polynomials via the Galerkin method to obtain the evolution of the eigenfunctions, so that the time evolution of any observable is descr...

A novel homotopic approach for convex low-thrust trajectory optimization is developed to improve convergence, accuracy, and computational effort compared to state-of-the-art methods. The homotopy is included in the optimization process where the homotopic parameter is updated continuously based on the constraint violation. This method is applied to...

Ballistic capture corridors allow a spacecraft to be temporarily captured about a planet without any thrust firing. They represent a promising approach for future deep-space small-satellites missions, where only limited fuel can be carried onboard. In an effort to enable autonomous interplanetary CubeSats, a guidance algorithm based on convex optim...

View Video Presentation: https://doi.org/10.2514/6.2022-1892.vid Different discretization and trust-region methods are assessed and compared for the low-thrust fuel-optimal trajectory optimization problem using successive convex programming. In particular, the differential and integral formulations of the adaptive pseudospectral Legendre--Gauss--Ra...

A robust algorithm to solve the low-thrust fuel-optimal trajectory optimization problem for interplanetary spacecraft is developed in this paper. The original nonlinear optimal control problem is convexified and transformed into a parameter optimization problem using an arbitrary-order Gauss-Lobatto discretization scheme with nonlinear control inte...

The space industry has recently witnessed a significant decrease of the overall costs of space missions, thanks to the miniaturization of satellites and their components. CubeSats have granted institutions and small companies access to space. However, space operations are still entirely performed from ground, limiting the potentiality of such space...

The low-thrust minimum-fuel trajectory optimization problem is solved in a high-fidelity model using convex optimization. The problem is convexified and dis-cretized with the Radau pseudospectral method. We apply a homotopic approach and successively increase the complexity and accuracy of the model to enhance convergence properties. Solar radiatio...

A closed-loop guidance method for low-thrust fuel-optimal interplanetary transfers is developed. The algorithm is based on convex programming and a flipped Radau pseudospectral discretization scheme. New reference trajectories are repeatedly recomputed in certain time intervals. The state of the spacecraft is propagated during these periods using t...

A robust algorithm to solve the low-thrust fuel-optimal trajectory optimization problem for interplanetary spacecraft is developed in this work. The original nonlinear optimal control problem is convexified and transformed into a parameter optimization problem using the adaptive flipped Radau pseudospectral discretization scheme. The switching time...