Programming efficient and reliable code can be considered a non-trivial task, as it requires deep understanding of the problem to be solved along with good programming skills. However, software frameworks and programming paradigms can provide a dependable infrastructure upon which better programs can be written and deployed. This allows engineers to focus mainly on their task, while relying on the underlying run-time environment for taking care of low-level programming issues, such as memory allocation and disposal, typing consistency and interface compliance. In this paper, we argue that strong-typed programming languages and paradigms offer a valid support for the production of reliable programs. Aware of the challenges of formal measurement metrics for code quality, we present the benefits of strong-typing by considering a practical application: the design and implementation of RoboX, a tour-guide robot for the Swiss National Exhibition Expo.02. The example is extremely well suited for such a discussion, since complex mechatronic applications can be considered critical systems - i.e., systems whose failure may endanger missions, lives and society - thus their reliability has to be made a prime concern.

Intelligent, autonomous service robots face unique challenges. Unlike autonomous guided vehicles used in manufacturing facilities, service robots cannot rely on clearly laid assumptions about the environment, as they share the work-space-which has not been designed around them-with human beings. At the same time, they cannot be treated as entertainment robots, since they are designed to accomplish a given set of tasks and their fate is measured by success-rate and not by their cuteness. Service robots need to perform reliably even during exceptional situations. The need for reliability strives for predictability, while the presence of a shared environment yields nondeterministic situations. The clash may be described as the paradox of mobile robotics, where reliability and safety are undermined by the same goals we want to reach. Based on the experience collected with the mobile mail distribution system MoPS, this paper describes a novel approach that is aimed at resolving the large number of error situations that can be addressed by untrained individuals, by allowing the robot to interact with passersby, if an exceptional situation is detected.

Nonlinear adaptive control schemes for robotic manipulators or new types of high speed machine tools with nonlinear dynamics are well suited to keep the tracking errors low, even at high speeds. Their application however requires fast microprocessors and an operating system that allows implementing the control algorithms as hard real-time tasks. The paper presents the implementation of a nonlinear model-based manipulator controller with adaptation algorithms on a new generation real-time operating system (RTOS) called XOberon. This RTOS goes beyond the established concepts, like interruptor priority-driven scheduling, bringing in new programming paradigms, such as deadline-driven scheduling. The superiority of this controller when applied to a fast 6 DOF parallel manipulator is finally shown by comparing its tracking performance with the one obtained using conventional linear controllers.

Starting from a user point of view the paper discusses the requirements of a development environment (operating system and programming language) for mechatronic systems, especially mobile robots. We argue that user require ments from research, education, ergonomics and applications impose a certain functionality on the embedded operating system and programming language, and that a deadline-driven real-time operating system helps to fulfil these requirements. A case study of the operating system XO/2, its programming language Oberon-2 and the mobile robot Pygmalion is presented. XO/2 explicitly addresses issues like scalabilty, safety and abstraction, previously found to be relevant for many user scenarios.