Ac 2011-2252: a Pen-based Statics Tutoring System

We present an intelligent pen-based tutoring system for Statics – the sub-discipline of engineering mechanics concerned with the analysis of mechanical systems in equilibrium under the action of forces. The system scaffolds students in the construction of free body diagrams and equilibrium equations for planar devices comprised of one or more rigid bodies. While there has been extensive research in intelligent tutoring systems, most existing systems rely on traditional WIMP (Windows, Icons, Menus, Pointer) interfaces. With these systems, students typically select the correct problem solution from among a set of predefined solution elements. With our pen-based interface, by contrast, students are guided in constructing solutions from scratch, mirroring the way they solve problems in ordinary practice, which recent research suggests is particularly important for effective instruction. Our system embodies several innovations including a novel instructional technique that focuses students’ attention on a system boundary as a tool for constructing free body diagrams, a tutorial feedback system based on “buggy-rules”, and a hierarchical feedback system which promotes independent problem-solving skills. In winter 2010, the tutoring system was used by 100 students in an undergraduate Statics course at the University of California, Riverside. Results from preand posttests reveal measurable learning gains even after only a short exposure to the system. In an attitudinal survey, students reported that, while there is room for improvement, the interface was preferable to a WIMP interface and the methodology implemented in the system was valuable for learning Statics.