Dynamic monitoring approach for verification of control software of robot using synchronized Petri nets

The verification of new intelligent robotic control algorithm not only requires the correction of computation but also satisfies the timing constraints. In this paper, a synchronized Petri nets model of robot control software is presented, in which an event set is introduced to indicate the start and end of a task module in control software design. With the help of the concept of inhibitor arc, the preemptive scheduling policy with fixed priority is modeled and furthermore, a new approach for dynamic monitoring of duration of a task module and performance evaluation of schedulability is presented. The presented model is applied in the Open Real-time Robot Controller-ORRC-I, developing under the Windows NT environment and a real-time extension RTX is adopted to assure real-time performance of control actions. Experiments of scheduling and synchronization of robotic control tasks prove the effectiveness of presented approach and show it suitable for scheduling complex algorithms with large variance in execution time.