# Kinematic and Dynamic Response of a Novel Engine Mechanism Design Driven by an Oscillation Arm
## 2 Simulation Method
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{5}{c}{**Initial Position of Joints Considering in Mechanism [mm]**} \\ \hline \multirow{2}{*}{**Joint**} & \multicolumn{2}{c}{Classic} & \multicolumn{2}{c}{VCR} \\ \cline{2-5}  & x & y & x & y \\ \hline
**O** & 0 & 0 & 0 & 0 \\
**A** & 0 & 38 & 0 & 38 \\
**B** & 0 & 165 & 43.15 & 63.5 \\
**C** & & & 0 & 207.2 \\
**D** & – & – & –120 & 80 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Kinematic input data. Figure 4: Piston stroke influence with modifying the pivot point on vertical direction. Table 2 contains an overview of results for all extreme positions of the pivot point (D) indicated in Figure 4 and for the initial position of this point. According to these results, it can be seen that moving point D on the right extreme position will lead to an increasing of stroke and a decrease of compression ratio relative to the initial position. Furthermore, the lowering of point D from initial position to the extreme down position will lead to an increase of stroke and compression ratio. According to Figure 4, moving the pivot point in the upward direction will reduce the piston stroke and will increase the chamber volume when the piston is close to the TDC. Furthermore, moving the pivot point in a horizontal direction, the piston stroke is also reduced (Figure 5). The stroke evolution on a complete crank angle rotation for different positions of the pivot point can be viewed on the both graphs from Figure 6.  
In Figure 6a, we see the increase of the piston stroke moving the pivot point to the right side. Furthermore, the increase of the piston stroke can be obtained based on moving the pivot point in the upward direction (Figure 6b). It can be seen that the moving point to the vertical direction has a greater influence compared to that against moving in the horizontal direction. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multicolumn{2}{c}{_D Point_} & \multirow{2}{*}{**Clearance[mm]**} & \multirow{2}{*}{**Stroke [mm]**} & \multirow{2}{*}{**Bore Diameter [mm]**} & \multirow{2}{*}{**Total Volume [L]**} & \multicolumn{2}{c}{**Clearance [L]**} & \multicolumn{2}{c}{**Compression**} \\ \cline{1-1} \cline{5-7} \multicolumn{2}{c}{**ExtremePosition**} & & & & & **Ratio (CR)** \\ \hline initial & 13.78 & 98.21 & 82 & 0.59 & 0.07 & 8.13 \\ Left & 9.80 & 94.88 \(\backslash\) & 82 & 0.55 & 0.05 & 10.68 \(\backslash\) \\ Right & 21.35 & 99.42 \(\backslash\) & 82 & 0.64 & 0.11 & 5.66 \(\backslash\) \\ Down & 6.18 & 105.7 \(\backslash\) & 82 & 0.59 & 0.03 & 18.1 \(\backslash\) \\ Up & 21.20 & 89.1 \(\backslash\) & 82 & 0.58 & 0.11 & 5.2 \(\backslash\) \\ \hline \hline \end{tabular} \(\
earrow\): Increase; \(\backslash\): Decrese.  
\end{table} 
Table 2: Output kinematic parameters for extreme position of pivot point D.  
Figure 5: Piston stroke influence with modifying the pivot point on horizontal direction. Figure 6: Piston stroke evolution during complete rotation of crankshaft when the pivot point is moved in: (**a**) horizontal direction (**b**) vertical direction. To have better comparative information regarding the two solutions, a graph with the stroke obtained for the classic solution was overlaid on Figure 6. It can be viewed that the stroke for the VCR solution (with point D in a nominal position) is increased by 25%. An improvement from the kinematic viewpoint will have an influence on the ratio compression and chamber volume and could also lead to improving the burning process on a complete cycle and consumption. Other kinematic parameters analyzed as a comparison can be viewed in Figure 7. This is about velocity and acceleration of the piston. Regarding the mechanism configurations analyzed, it can be viewed from the graphs that higher values are obtained using the VCR solution in comparison to the classic solution.