A Software Tool For Understanding Nonlinear Phenomena In Hydraulic And Pneumatic Systems

Hydraulic and pneumatic systems are highly nonlinear and difficult to analyze. These systems exhibit nonlinear behavior because of restricted flows, finite cylinder length and non-negligible static and dynamic frictions. Pneumatic system non-linearity is even stronger because of air compressibility. It is always a challenge to explain the effects of these nonlinear phenomena on the overall system behavior. This paper presents a software tool developed to help students understand these complex phenomena without resorting to sophisticated finite element analysis. In order to achieve this goal, we first define a set of domain concepts that are central to the modeling and understanding of hydraulic and pneumatic phenomena (section 3). We then proceed to identify the most important misconceptions carried by students who don’t have a good grasp of the phenomena (section 4). This identification task is based on a constructivist model of the learning process. Particularly the constructivist paradigm and the model of conceptual conflict (section 2). Finally, we design and construct a software application tailored to help correct those misconceptions (section 5). Thus, the focus point here is to design an environment that enables the learner, in conceptual conflict, to reach cognitive equilibrium by reorganizing his conceptual structures. The specific environment discussed in this paper is a software application. Its aim is to facilitate learner – subject interactions through experimentation and to assist the learner in reorganizing his conceptual structures. 2. Constructivist model of the learning process The inability to explain simple physical phenomenon and a student’s own mental representation of the situation have been linked by a number of classical works 1 . These observations give rise to the so-called Constructivist Paradigm of Learning. Within this paradigm, the learning process is a gradual construction process based on the interactions created between the learner and the