International Journal of Artificial Intelligence & Applications (IJAIA), Vol.1, No.3, July 2010 considerably lower impact (for example, look at the small increment of the cost when the required energy is constant, between   8 **and**   **22**). 

## 5. C**Onclusions**

In this paper we have shown how model checking based planning, and in particular the UPMurphi universal planner**, can be profitably exploited to generate time and resource-optimal** plans to control the engine of an autonomous planetary vehicle during an exploration mission. 

The general characteristics of this kind of vehicle, together with the environmental conditions and the mission constraints, often lead to hybrid models with nonlinear dynamics, which are difficult to manipulate for most of the other planning tools. Therefore, planning in this context is often performed using only semi-automatic or even manual techniques on simplified models, whose results need to be checked for correctness and safety through simulation. Obviously, calculating a resource-optimal plan is even harder.

The UPMurphi optimal planner simplifies this process by automatically handling the system in its full complexity. Thus, the application of UPMurphi can be helpful to plan the activities of complex, realistic models of autonomous vehicles. Indeed, we are working to further enhance the tool capabilities in order to handle more complex dynamics equations, in particular the ones involving differential equations, and to implement advanced state space pruning heuristics. On the other hand, we are studying how to use the UPMurphi in simulation mode to *automatically* **validate the generated plans, thus providing a** 
meaningful plan analysis to the user, which may include, e.g., some of the plots shown in this paper. 

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