Development and analysis of a PC-based object-oriented real-time robotics controller

Real-time controllers have traditionally used computer hardware systems that require expertise in hardware knowledge before the controller can be effectively implemented. This paper introduces a single-processor PC-based real-time motion controller developed using QNX 6.0 Neutrino operating system. Using the advantages of a distributed software system and an object-oriented architecture, the developed controller can be easily modified to suit any application. Common real-time software development issues such as timing, data logging and hardware management are discussed in detail, along with straight-forward solutions to address these problems in QNX. The entire system is implemented on a 2-D cable-based high-speed pick-and-place robot, and the controller performance is compared to Delta Tau PMAC, a commercial controller. Developing a PC-based modular real-time controller allows researchers to easily implement their control algorithms at a reasonable cost.