K’nexing Models To Examples In Engineering Mechanics

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The transition from Statics to Dynamics is often difficult for students, especially in their sophomore year. Where previously everything was stationary, now the possibility of movement enters into the analysis process. This can be challenging, particularly for visual learners, when asked to evaluate motion using only a two-dimensional, static picture or diagram. The use of informal models and in-class activities have been employed by the authors on a continual basis in the combined statics and dynamics course, and while the statics portion traditionally progresses smoothly, students often comment that it is difficult to understand the motion for the dynamics portion, even with models used in class. Endeavoring to improve student visualization, and building off of the idea that teaching a concept will further strengthen ones understanding of the material, the engineering mechanics faculty incorporated a student project to create a K’NEX model which demonstrates kinematic principles presented in class. Students not only had to design a physical model, but also had to include a worksheet with a problem statement, an associated diagram of the model, and a complete solution page. The original intent of the project was to deepen the students understanding and to reinforce the concepts of kinematic motions – Translation, Rotation, Rotation About a Fixed Axis, and General Plane Motion. After two semesters of refining the project, the professors intend to incorporate previous semesters’ projects into in-class learning activities; each group of students (generally between four and six) will be given a model along with the worksheet and work through a solution for position, velocity or acceleration dependent on the question addressed in the problem statement. There are three classes devoted to these dynamics principles, and the instructors will incorporate a different in-class learning activity into each lesson. It is the authors’ goal to increase student comprehension of dynamic concepts by allowing them to do more than simply observe the motion (as was done for previous semester in-class activities); students will create the motion utilizing hands-on dynamic models which they will construct in class and then solve for the variables of kinematic motion. Most engineering students are visual, sensing, active, sequential and inductive learners while most teaching is verbal, intuitive, sequential and deductive . In an effort to change the teaching style to address the students preferred learning styles, the K’NEX projects and subsequent inclass worksheets address visual, sensing, active and inductive learning styles. To assess student learning, comparisons will be made of students with no model usage, students who created models but did not utilize the model/worksheet in-class activities, and those students who not only created, but also were exposed to hands-on activities using models during the dynamic lessons. Assessment of actual and perceived gains in topic comprehension will be performed via grade distributions on dynamics tests versus previous semesters, Likert surveys of students, student comments, and student self assessment of concept understanding versus previous semesters. Comments are summarized from two sections of students in Fall 2009 (70 students total), and exam averages compared Fall 2009 with four previous semesters. Page 15828.1 Educational Atmosphere Engineering Mechanics at Florida Gulf Coast University is a combined 4 credit hour Statics and Dynamics course which students typically take during their sophomore year. Offered as one of the interdisciplinary courses, the roster contains students in bioengineering, civil engineering, and environmental engineering. Topics in statics and dynamics are discipline specific in various courses offered in the curriculum at the junior and senior levels. The majority of engineering courses at Florida Gulf Coast University are offered in the integrated lecture-lab format. This means that for a four credit course, class meets twice a week for 2 3⁄4 hours each time. Because of the extended class period, presenting the necessary material in an engaging format and not overloading students on new concepts requires additional considerations over what might occur in a course that has 50-minute sessions three times a week. Dynamics accounts for approximately 40% of the course content, and roughly 42% of the course grade. Compared to a traditional course offering, this course meets the equivalent of 84 -50 minute lessons of which 34 are devoted to dynamics; this is only 8 lesson less than a full semester of 4250 minute lessons of dynamics. Engineering Mechanics is divided into five sections, each with an associated exam. Sections are varied in length and exam weight is adjusted accordingly. Dynamics is covered in sections four and five, with the first of these being kinematics and the second kinetics. Three class periods are utilized to present the kinematic concepts of translation, rotation, and general plane motion. The concepts are reinforced as a review session with worksheets in the fourth class, and the fifth class period of kinetics is an exam. The combination of a compressed schedule and integration of movement into situations that were previously stationary results in many students feeling overwhelmed with the subject. For many of the students, particularly the visual learners, the confusion stems not from the calculations, but rather from the determination of what motion is actually occurring. Motionless 2-dimensional figures were satisfactory for illustrating reactions and forces for static conditions but often prove to be ineffective in conveying kinematic principles, particularly in the introductory phase of learning. The concerns and frustrations exhibited by the students prompted the authors to consider potential measures to resolve these concerns. Three levels of activities were developed to assist with these concerns.