SCOTCH-YOKE

Total number of links: _____

Total number of joints: _____

Degrees of Freedom: _____
    

DRIVING CRANK SPEED

RPM: _______     =    rad/sec: __________

ANALYSIS

Explain why the slider-crank mechanism doesn't display true sinusoidal motion (in the x-direction) while the scotch-yoke does.

Using the theoretical data from the Excel spreadsheet, investigate the effect of changing the link lengths. What effect does a small joint length to crank length (l/r) ratio have on the output motion? What about a large ratio? (FYI, see the animation showing the result of a ratio of 1.)

Compare the force and transmission angle vs. crank angle plots (for the slider-crank) from the experimental data. Make observations about the relationship between the two for different linkage geometries?

Which angle (i.e., driver-crank angle, driver-coupler angle, coupler-slider angle) is the best indicator of maximum force on the slider? Why?

How does the output motion of the experimental data compare to that of the theoretical data (both the theoretical data derived from the equation of motion and from the SLIDER program) for the slider-crank mechanism?

PLOTS

1. Experimental & Theoretical Position vs. Driver Crank Angle for slider-crank.
2. Experimental & Theoretical Position vs. Driver Crank Angle for scotch-yoke.
3. Theoretical Position vs. Driver Crank Angle for slider-crank compared to scotch-yoke.
4. Force vs. Angle for scotch-yoke.
5. Theoretical Position vs. Driver-Crank Angle (for slider-crank) from screen shot of SLIDER program.
6. Theoretical Transmission Angle vs. Driver-Crank Angle(for slider-crank) from screen shot of SLIDER program.