Mechanix: Evaluating the Effectiveness of a Sketch Recognition Truss Tutoring Program against other Truss Programs

摘要

Mechanix is a sketch recognition program that was developed at Texas A&M University. Mechanix provides an efficient and effective means for engineering students to learn how to draw truss free-body diagrams (FBDs) and solve truss problems. The Mechanix interface allows for students to sketch these FBDs, as they normally would by hand, into a tablet computer; a mouse can also be used with a regular computer monitor. Mechanix is able to provide immediate and intelligent feedback to the students, and it tells them if they are missing any components of the FBD. The program is also able to tell students whether their solved reaction forces or member forces are correct or not without actually providing the answers. A recent and exciting feature of Mechanix is the creative design mode which allows students to solve open-ended truss problems; an instructor can give their students specific minimum requirements for a truss/bridge, and the student uses Mechanix to solve and create this truss. The creative design feature of Mechanix can check if the students' truss is structurally sound, and if it meets the minimum requirements stated by the instructor. This paper presents a study to evaluate the effectiveness and advantages of using Mechanix in the classroom as a supplement to traditional teaching and learning methods. Mechanix is also tested alongside an established and popular truss program, WinTruss, to see how learning gains differ and what advantages Mechanix offers over other truss analysis software. Freshman engineering classes were recruited for this experiment and were divided into three conditions: a control condition (students who were not exposed to Mechanix or WinTruss and did their assignments on paper), a Mechanix condition (students who used Mechanix in class and for their assignments, and a WinTruss condition (students who used the WinTruss program for their assignments). The learning gains among these three groups were evaluated using a series of quantitative formal assessments which include a statics concepts inventory, homework sets, quizzes, exam grades and truss/bridge creative design solutions. Qualitative data was also collected through focus groups for all three conditions to gather the students' impressions of the programs for the experimental group and general teaching styles for the control group. Results from previous evaluations show Mechanix highly engages students and helps them learn basic truss mechanics. This evaluation will be compared with previous evaluations to show that Mechanix continues to be a great tool for enhancing student learning.