Prototyping Advanced Real-Time Robotic Controllers on Linux RTAI Systems with Automatic Code Generation

Abstract

The use of industrial robots in research and teaching laboratories proves difficult since the closed controller software and the proprietary hardware architecture prevent the execution of experiments testing advanced control algorithm, or the integration of new sensors not present on the original robot. The integration of external sensors, such as force/torque sensors or cameras for vision-in-the-loop control, is the first step toward a new class of algorithms allowing interaction with the environment at low costs and within industrial standards. The real-time nature of the control task, that sets tight temporal constraints on the algorithm step completion, forces the user to devote a large part of the design time to topics remote from the main issues of the controller design, chiefly when he/she is not interested in software implementation issues. This paper presents a low-cost robot controller prototyping architecture, based on Simulink-Stateflow design environment. One of its main characteristics is the automatic generation of the real-time execution code for the target processor, that runs under Linux RTAI operating system. To show the applicability of the proposed solution, rapid prototyping of force control algorithms is experimentally tested on a COMAU Smart S2 6DoF articulated industrial ma-nipulator, endowed with a force-torque sensor mounted on its tip. 1