n1i 20 "Number of teeth, first gear (input shaft)"
n2i 20 "Number of teeth, second gear (input shaft)"
n3i 20 "Number of teeth, third gear (input shaft)"
n4i 20 "Number of teeth, fourth gear (input shaft)"
n1o 76 "Number of teeth, first gear (output shaft)"
n2o 44 "Number of teeth, second gear (output shaft)"
n3o 28 "Number of teeth, third gear (output shaft)"
n4o 20 "Number of teeth, fourth gear (output shaft)"
gear_ratio1 n1o/n1i "Gear ratio, first gear"
gear_ratio2 n2o/n2i "Gear ratio, second gear"
gear_ratio3 n3o/n3i "Gear ratio, third gear"
gear_ratio4 n4o/n4i "Gear ratio, fourth gear"
cdy 10[cm] "Center distance between shafts"
cdx 5[cm] "Center distance between gears"
d1i 2*cdy/(1+gear_ratio1) "Pitch diameter, first gear (input shaft)"
d1o 2*cdy-d1i "Pitch diameter, first gear (output shaft)"
d2i 2*cdy/(1+gear_ratio2) "Pitch diameter, second gear (input shaft)"
d2o 2*cdy-d2i "Pitch diameter, second gear (output shaft)"
d3i 2*cdy/(1+gear_ratio3) "Pitch diameter, third gear (input shaft)"
d3o 2*cdy-d3i "Pitch diameter, third gear (output shaft)"
d4i 2*cdy/(1+gear_ratio4) "Pitch diameter, fourth gear (input shaft)"
d4o 2*cdy-d4i "Pitch diameter, fourth gear (output shaft)"
alpha 25[deg] "Pressure angle"
omega 80[rad/s] "Engine or input shaft speed"
omega_c 15[rad/s] "Cam speed"
T_ext 0.1[N*m] "Resisting torque"
tf 1.33[s] "Final time"