Background
Bakhirkin and Basset recently proposed a specification language that extends Signal Temporal Logic (STL), lifting its syntactic restrictions: it can produce and manipulate real-valued output signals and express properties usually described with other logics, such as STL*.
The contribution
This paper extends that language in three directions:
- An integral operator over sliding windows, to specify cumulative properties, for example that the integral of a signal over a time interval stays within a threshold.
- A filtering operator for sliding windows, restricting the aggregation to the signal segments that satisfy a given condition.
- An efficient online monitoring algorithm for the extended logic.
The logic is evaluated on two case studies.