Energy efficient trajectory generation for a state-space based JPL Aerobot

The 40th anniversary of Apollo 11 project with man landing on the moon reminds the world again by what science and engineering can do if the man is determined to do. However, a huge step can only be achieved step by step which may be relatively small at the beginning. Robotic exploration can provide necessary information needed to do the further step safely, with less cost, more conveniently. Trajectory generation for a robotic vehicle is an essential part of the total mission planning. To save energy by exploiting possible resources such as wind will assist a robotic explorer extend its life span and perform tasks more reliably. In this paper, we propose to utilize Nonlinear Trajectory Generation (NTG) methodology to generate energy efficient trajectores for the JPL Aerobot by exploiting wind. The Aerobot model is decoupled into longitudinal and lateral dynamics with control inputs as elevator deflection δ_e, thrust demand δ_T, vectoring angle δ_v for the longitudinal motion, aileron deflection δ_a, rudder deflection δ_r for the lateral motion. The outputs are the velocities and orientation of the Aerobot. The Aerobot state space model parameters are obtained from experimental identification on AURORA Airship since the actual JPL Aerobot is similar to the AURORA Airship. In this paper, the results show that with the state-space model, the proposed trajectory generation method can guide the Aerobot to take advantage of previously known wind profile to generate an energy-efficient trajectory.