Software design of sensor-based robot skills

A paradigm for sensor-based robot programming is discussed where robotic operations are created by combining predetermined robot skills. The creation of these skills and the tools required to design them are the main subjects of this paper. The most difficult aspect of designing sensor-based robot skills is to guarantee that realtime deadlines will be met. System design tools for realtime systems are required that will predict if the intended system functionality will be met in practice. In robot skills design, the tools can be simplified because the interfaces to sensors and robots have restricted behaviour. A coordination language is presented that allows the designer to predict the behaviour of the software modules which cooperate as a system. The language is represented in both graphical and textual form, and is complemented by timing charts. The creation of a robot skill that uses a force-torque sensor in the robot control loop is used as an example to demonstrate these concepts. It is shown that these tools create a means to predict the realtime behaviour of a system incorporating multiple devices