   modelling a drivetrain
  Hi,I would like to improve my drivetrain model.It should include a engine, a clutch, a gearbox, a differential (3 for 4WD), and 2 wheels (4 for 4WD).The available data so far:  - engine: torque characteristics, friction torque characteristics, current rpm, inertia;  - clutch: torque generated by friction in it; - gerabox: ratioes, friction torque; - differential: final ratio, torque bias (for 4WD middle diff.), perhaps friction torque; - each wheel: angular velocity, radius, braking torque, torque of traction, inertia, rolling resistance torque;So this is a mechanical system with inertias, torques, angular velocities. Nothing else.I would like to have an acceptable model including the braking effect of the engine. The clutch is the most interesting for me. My current model does not include it. I would like to make the clutch automatic somehow.So how can I describe the rotation of the system with Newton''s laws? I know tha these. The most important is F=m*a, T=I*A, I just cannot apply them in this case Any idea, working solution, equation, good link is appreciated.Thanks in advance 