1. Undergraduate Engineering Mechanics at the ETH Stephan Kaufmann Institute of Mechanical Systems ETH Zürich

2. Outline http://www.ifm.ethz.ch/~kaufmann/owf/ Curriculum The computer as a teaching aid MECA Simulations  Java applets  Mathematica packages

3. Engineering Mechanics Courses 3-semester course (Dual/Sayir) Mechanical and Process Eng. (200 stud.; 3 sem.) Civil Eng. (60 stud.; 2.5 sem.) Materials Sciences (60 stud.; 2 sem., 3 rd optional) 1-semester course (Brauchli) Electrical Eng. (160 stud.; 1 st sem.) 1-semester course (Kaufmann) Environmental and Geomatics Eng. (60 stud.; 2 nd sem.)

4. Organization (Mech. & Proc. Eng.) 1 st Sem.2 nd Sem.3 rd Sem. Lectures3h 4h Exercise Classes 2h Colloquium0.5h - Tests333 Exams1 st prelim. diploma 2 nd prelim. diploma

5. 1 st Semester (Statics) Kinematics of rigid bodies (velocities) Forces, moments, systems of forces, resultant, moment resultant, equivalence, reduction, center of gravity, power Principle of Virtual Power, equilibrium Supports, systems, trusses Friction, cables Shear force, bending- and torsional moment

6. 2 nd Semester (Strength of Materials) Stress tensor, Mohr´s circle Strain tensor Linear elasticity Deflections of beams Torsion Deformation energy, Castigliano´s theorem Buckling of beams Plasticity

7. 3 rd Semester (Dynamics) Acceleration Equations of motion (d´Alembert, PVP) Vibrations (1 and N degrees of freedom) Vibrations of beams: longitudinal, bending Waves in beams: longitudinal, bending Relative motion Kinetics of rigid bodies in 3-d, gyroscopes Lagrange´s equations Impact or (gravitation + introd. to spec. rel.)

8. MECA: Ideas Fill in the gap between lectures and exercises (passive/active learning) Place a "24h-teacher" at the student´s disposal Lead the students through "good" solutions of home exercises Force the students to think about aspects which usually are forgotten (modeling etc.) Show and prevent the well-known pitfalls The system is optional and anonymous The system must be user-friendly!

9. MECA: Demonstration Click icon to start MECA

10. MECA: History Pilot project 85-88 Prototypes + pilot group Authoring system by SK Teachware by professors and assistants Serious didactical evaluation was impossible Unexpected: positive social effect Dedicated MECA-room with 20 Macs: 1988-98 Java-version in 1998 (3 months)

11. MECA: Conclusions The students´ feedback is very polarized: from "very good" to "useless" The system seems to be attractive mainly for less talented students These students tend to spend a lot of time on the system, working with a questionable didactical efficiency A great majority of the students want the system to be available Teachware is very expensive

12. Simulations: Ideas Computer simulations of dynamical effects in lectures Complement real experiments Allow the students to run simulations and explore effects on their own computers

13. Simulations: History 1985-1986: Development of some programs on a PC (R. Triebe) 1986-1989: New programs for the Mac using DialogMachine (several students and SK) since 1999: new implementations using Java (M. Bergdorf and SK)

14. Simulations: Examples Pole curve Cycloids Planet gear Pendulum Double pendulum Oscillator

15. Mathematica Package The package is available at: http://www.ifm.ethz.ch/~kaufmann/ http://www.ifm.ethz.ch/~kaufmann/ This notebook contains a sample: BeamBeam