Mechanix: A Sketch‐Based Tutoring and Grading System for Free‐Body Diagrams

Abstract

Introductory engineering courses within large universities often have annual enrollments which can reach up to a thousand students. It is very challenging to achieve differentiated instruction in classrooms with class sizes and student diversity of such great magnitude. Professors can only assess whether students have mastered a concept by using multiple choice questions, while detailed homework assignments, such as planar truss diagrams, are rarely assigned because professors and teaching assistants would be too overburdened with grading to return assignments with valuable feedback in a timely manner. In this paper, we introduce Mechanix, a sketch-based deployed tutoring system for engineering students enrolled in statics courses. Our system not only allows students to enter planar truss and free body diagrams into the system just as they would with pencil and paper, but our system checks the student's work against a hand-drawn answer entered by the instructor, and then returns immediate and detailed feedback to the student. Students are allowed to correct any errors in their work and resubmit until the entire content is correct and thus all of the objectives are learned. Since Mechanix facilitates the grading and feedback processes, instructors are now able to assign free response questions, increasing teacher's knowledge of student comprehension. Furthermore, the iterative correction process allows students to learn during a test, rather than simply displaying memorized information.

Mechanix: A natural sketch interface tool for teaching truss analysis and free-body diagrams

“…The inner workings of Mechanix and the artificial intelligence behind the scenes have been documented in detail in Field et al (2011) and Kebodeaux et al (2011) and most completely in Valentine et al (2012, 2013). Because the details of the Mechanix software have already been documented in detail, we provide summaries of these aspects in the following subsections.…”

“…With all of this information gained about the truss, Mechanix determines whether the constraints of the problem were met. More in-depth information about truss analysis can be found in Valentine et al (2012, 2013).…”

Promoting Sketching in Introductory Geoscience Courses: CogSketch Geoscience Worksheets

“…Artificial intelligence researchers have explored techniques for interpreting sketches, including the use of highly specialized sketch recognition algorithms (e.g., Taele, Barreto, & Hammond, ; Valentine et al., ) and/or cognitive models of sketch understanding (Forbus, Usher, Lovett, Lockwood, & Wetzel, ). Sketch recognition works well for domains where there is a well‐defined mapping between symbols and concepts.…”

Using Natural Sketch Recognition Software to Provide Instant Feedback on Statics Homework (Truss Free Body Diagrams): Assessment of a Classroom Pilot

“…Researchers have recently developed the free "Mechanix 1 " sketch recognition tutoring system for free body diagrams (FBDs) and trusses. The Mechanix online software provides instantaneous and detailed feedback using a natural sketch recognition engine 2,3,4,5,6,7,8,9,10,11,12 .…”

“…Researchers have recently developed the free "Mechanix 1 " sketch recognition tutoring system for free body diagrams (FBDs) and trusses. The Mechanix online software provides instantaneous and detailed feedback using a natural sketch recognition engine 2,3,4,5,6,7,8,9,10,11,12 .This paper describes the process and results of piloting the Mechanix software at a primarily undergraduate university. The experimental group included 39 students in a Statics class, contrasted with a similar class of 34 as a control group.…”