A Pen-Based Statics Tutoring System

Abstract

We present an intelligent pen-based tutoring system for Statics - the sub-discipline of engineering mechanicsconcerned with the analysis of mechanical systems in equilibrium under the action of forces. The systemscaffolds students in the construction of free-body diagrams and equilibrium equations for planar devicescomprised of one or more rigid bodies.While there has been extensive research in intelligent tutoring systems, most existing systems relyon traditional WIMP (Windows, Icons, Menus, Pointer) interfaces. With these systems, students typicallyselect the correct problem solution from among a set of predefined choices. With our pen-based interface, bycontrast, students are guided in constructing solutions from scratch, mirroring the way they solve problemsin ordinary practice, which recent research suggests is particularly important for effective instruction.Our system embodies several innovations including a novel instructional technique that focusesstudents' attention on a system boundary as a tool for constructing free body diagrams, a tutorial feedbacksystem based on buggy rules that attempt to diagnose and correct problem-solving errors typical of novicestudents, and a hierarchical feedback system which promotes independent problem-solving skills. In winter2010, the tutoring system was used by 100 students in an undergraduate Statics course at our university.Results from pre- and posttests reveal measurable learning gains even after only a short exposure to thesystem. 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 forlearning Statics.