**8. Conclusion**

An onboard trajectory planner based on the Inverse Dynamics in the Virtual Domain direct method presented in this chapter is an effective means of augmenting an unmanned maritime vehicle's autopilot with smooth, feasible trajectories and corresponding controls. It also facilitates incorporation of sophisticated sensors such as forward-looking sonar for deliberative and reactive obstacle avoidance. This approach has been implemented on both unmanned undersea and surface vehicles and has demonstrated great potential. Beyond its ability to compute near-optimal collision-free trajectories much faster than in real time, the proposed approach supports the utilization of any practically-sound compound performance index. This makes the developed control architecture quite universal, yet simple to use in a variety of applied scenarios, as demonstrated in several simulations and preliminary sea trials. This chapter presented results from only a few preliminary sea trials. Future research will continue development of the suggested trajectory framework in support of other tactical scenarios.
