Prediction-based guidance algorithm for high-lift reentry vehicles

Abstract

In this work, we propose a pseudo four-degrees-of-freedom (DOF) prediction based guidance algorithm specifically for high-lift reentry vehicles. The algorithm is composed mainly of three parts. First, at the beginning of each guidance cycle, the 4-DOF predictor is called upon to predict the final downrange, crossrange, and heading errors. Then, the magnitude of the bank angle is determined from the downrange error, using the proportional-integral (PI) control method. Finally, two bank angle reversal time points are determined to minimize the crossrange and heading errors. Compared with traditional predictor-corrector guidance, the algorithm proposed does not require iterative procedures which significantly decreases the computational burden for the on-board computer and makes the implementation practical. Simulation results for dispersion tests demonstrated that our algorithm is computationally efficient and robust against uncertainties and disturbances.

On-line optimal autonomous reentry guidance based on improved Gauss pseudospectral method

“…Control (49) can only be used at the interval of [t i , t i+1 ]. Then the trajectory of the system is called Carathéodory-π solutions [8]. If the optimal control can be fulfilled immediately, control (49) can be called the optimal feedback guidance law for the trajectory tracking problem.…”

“…Lemma 2 (Gronwall's inequality) [8]. Let [t 0 , t f ] → y(t) ∈ R + be an integrable function that satisfies Gronwall's inequality:…”

“…Therefore, the predictor-corrector guidance has a little autonomy for guiding the hypersonic vehicle to the destination. The proposed predictor-corrector guidance of [8] can autonomously guide the hypersonic vehicle to the desired station. However, the real trajectory is not the optimal trajectory from the current state to the final place.…”

“…The optimal autonomous reentry guidance could discover the potential of the hypersonic vehicle through optimization so that it has great autonomy. The lateral error is corrected by the bank reversal algorithm [8]. After the second bank reversal, the guidance algorithm presented in [8] had no control capability on the lateral motion; that is, lateral uncer-http://engine.scichina.com/doi/10.1007/s11432-013-4922-6 tainty such as wind cannot be corrected.…”

Constrained predictor corrector entry guidance for common aero vehicle

“…The aim of onboard predictor-corrector entry guidance is to calculate the current command bank angle repeatedly if the attack angle profile is determined before [1][2][3]. There are path constraints [4][5][6][7] in the entry guidance, hence an accurate aerodynamic model is needed to calculate a correct trajectory.…”