Table 5 Transmission ratio and partial derivative in the acceleration gear 6.

From: Performance analysis and optimization design of variant CR-CR 9-speed automatic transmission

Transmission ratio\({i_6}\)

\(\frac{{{n_i}}}{{{n_o}}}=\frac{{({K_1}+1)({K_4}+1)}}{{1+{K_1}+{K_4}+{K_1}{K_3}+{K_1}{K_4}}}\)

\(ln{i_6}\)

\(\ln [({K_1}+1)({K_4}+1)] - \ln (1+{K_1}+{K_4}+{K_1}{K_3}+{K_1}{K_4})\)

Partial derivative

 

\(\frac{{\partial \ln {i_6}}}{{\partial {K_1}}}\)

\(\frac{{{K_4}+1}}{{({K_1}+1)({K_4}+1)}} - \frac{{{K_3}+{K_4}+1}}{{1+{K_1}+{K_4}+{K_1}{K_3}+{K_1}{K_4}}}\)

\(\frac{{\partial \ln {i_6}}}{{\partial {K_2}}}\)

0

\(\frac{{\partial \ln {i_6}}}{{\partial {K_3}}}\)

\(- \frac{{{K_3}}}{{1+{K_1}+{K_4}+{K_1}{K_3}+{K_1}{K_4}}}\)

\(\frac{{\partial \ln {i_6}}}{{\partial {K_4}}}\)

\(\frac{{{K_1}+1}}{{({K_1}+1)({K_4}+1)}} - \frac{{{K_1}+1}}{{1+{K_1}+{K_4}+{K_1}{K_3}+{K_1}{K_4}}}\)