Quantitative evaluation of unmanned ground vehicle trajectory based on chaos theory

The quantitative evaluation of unmanned ground vehicles is difficult. For this problem, we propose a quantitative evaluation method based on chaos theory. First, the ideal trajectory of an unmanned ground vehicle was designed applying the quintic polynomial method, and the deviation time series were obtained by calculating the deviation of the actual trajectory from the ideal trajectory. Then, the phase space of the deviation time series was reconstructed based on the improved algorithm using correlation integral method. Finally, the Lyapunov exponent of the deviation time series was calculated, which was the quantitative presentation of the unmanned ground vehicle's trajectory. The quantitative presentation of the unmanned ground vehicle's trajectory for lane keeping, obstacle avoidance, and overtaking lane changing was achieved. The Lyapunov exponent of lane keeping was the least, so the maximum predicted time was the longest. Lane keeping was done the best of all. Experimental results show that the quantitative evaluation method based on chaos theory for unmanned ground vehicle trajectory is feasible and effective.