Mechanix: A Sketch-Based Educational Interface Trevor Nelligan Sketch Recognition Lab Texas A&M University trevornelligan@tamu.edu Seth Polsley Sketch Recognition Lab Texas A&M University spolsley@tamu.edu Jaideep Ray Sketch Recognition Lab Texas A&M University jaideep.ray@tamu.edu Dr. Michael Helms iDreem Lab Georgia Institute of Technology mhelms3@gatech.edu Dr. Julie Linsey iDreem Lab Georgia Institute of Technology julie.linsey@me.gatech.edu Dr. Tracy Hammond Sketch Recognition Lab Texas A&M University hammond@cse.tamu.edu ABSTRACT At the university level, high enrollment numbers in classes can be overwhelming for professors and teaching assistants to manage. Grading assignments and tests for hundreds of students is time consuming and has led towards a push for software-based learning in large university classes. Unfor- tunately, traditional quantitative question-and-answer mech- anisms are often not sufficient for STEM courses, where there is a focus on problem-solving techniques over find- ing the right answers. Working through problems by hand can be important in memory retention, so in order for soft- ware learning systems to be effective in STEM courses, they should be able to intelligently understand students sketches. Mechanix is a sketch-based system that allows students to step through problems designed by their instructors with per- sonalized feedback and optimized interface controls. Opti- mizations like color-coding, menu bar simplification, and tool consolidation are recent improvements in Mechanix that fur- ther the aim to engage and motivate students in learning. Author Keywords Guides; Computer-assisted Instruction (CAI); Graphical User Interfaces (GUI); Interaction Styles; User-centered design ACM Classification Keywords H.5.2 Information Interfaces and Presentation (e.g. HCI): K.3.1Computer Uses in Education INTRODUCTION Sketching is one of the most important problem-solving tech- niques students can use. No matter their discipline, students everywhere draw diagrams, tables, and scratch work to help Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for third-party components of this work must be honored. For all other uses, contact the Owner/Author. Copyright is held by the owner/author(s). IUI’15 Companion, March 29–April 1, 2015, Atlanta, GA, USA ACM 978-1-4503-3308-5/15/03. http://dx.doi.org/10.1145/2732158.2732194 them illustrate and understand concepts. Students benefit from learning to draw engineering drawings by hand [12] [5], yet, as high enrollment in university courses and efforts to reduce costs is pushing many schools toward software-based teaching tools, the natural interaction of sketching is often lost. STEM (Science, Technology, Engineering, and Math- ematics) fields are particularly good candidates for software teaching systems, owing to the complexity of content and dif- ficulty in finding qualified graders, but existing systems are often insufficient for these courses. Because of an emphasis on technique and understanding over calculating the correct answer, STEM courses are difficult to grade through purely quantitative question-and-answer mechanisms. It is impor- tant that teaching software in STEM courses be more flexible and intuitive so that the focus is on student learning. Mechanix is an interactive teaching tool designed to help stu- dents through the complete process of creating and solving truss and free body diagram problems [13] [4]. Mechanix uses a combination of sketch recognition and numerical ques- tions to evaluate student work and provide personalized feed- back [1]. In this way, students are free to work through a problem by hand, but they still must adhere to the guidelines of the question, as defined by the instructor, in order to re- ceive credit. Although this project has been under develop- ment for some time, Mechanix was recently deployed across classes in three universities in a newly-improved form. The new interface includes an enhanced layout with more natural groupings of features and controls. PRIOR WORKS Technology-based solutions for teaching engineering, even some systems that include sketching, are not new. Sketch Worksheets is a domain-free sketch-based system for walk- ing students through any problem designed by the instructor, but it requires that instructors be comfortable with a special language in order to define facts about the sketch that may be used to guide students [14]. Other packages such as Win- Truss [11], Bridge Architect, and McGraw Hill Connects en- gineering section provide software-based truss problem solv- ing. These systems do not include sketching, and so must fill in areas of the solution and ask students to provide missing 1 IUI 2015 • Poster & Demo Session March 29–April 1, 2015, Atlanta, GA, USA 53