Obstacle avoidance trajectory optimization of hypersonic vehicle

To avoid the obstacle region, the trajectory of the hypersonic vehicle is optimized based on the control parametrization and the noncontinuous constraints transformation. The fly environment of the hypersonic vehicle is very severe and there is much disturbance and uncertainty, which results in a troublesome task to plan the trajectory especially with obstacle. The aim is to design an optimal obstacle avoidance trajectory to maximize the range under the heating rate, dynamic pressure and overload constraints for a fixed fuel consumption. Because the obstacle constraints are noncontinuous constraints, it is difficult to obtain its gradient. Based on the constraint transformation the noncontinuous constraints are changed into the canonical constraint equally. The time axis is divided into some segments with different lengths, which increase the optimization freedom and get the better results than that of the method with equal segments. The proposed method is compared with the conventional method by numerical simulations and the proposed method has the better results than that of the conventional one.