For that problem we have decided to vary the number of parameters:

  • "b1" refers to the geometrical length of the rocker;
  • "b2" refers to the position of the centre of the circular surface of contact of the rocket;
  • "c" is another quantity, which relates the distance between the axle of the camshaft and the bearing of the rocker;
  • "rf" is another geometrical quantity, which defines again the centre point of the surface of contact of the rocket;
  • "ss" is the stiffness of the return spring on the valve;
  • "sp" is the pre-load of the same spring.
The original values of the system that we were going to improve are reported in this list and also you can see the range that we have set in order to allow these parameters vary within a not so wide range.
I just show you the results of the optimisation that have been obtained by using a SUMT algorithm. What is SUMT algorithm sequential unconstrained minimisation technique? It is an algorithm, which works in the framework work of non-linear programming. We have maximised the angular speed of the camshaft, while we have constrained all the performance criteria introduced before. After the process has been initiated, the results have been the one that I can show you in these two schemes. As function of the cam angle here the first scheme reports the flash temperature. In the second scheme, we see the specific work of friction forces which is always the same for the two systems, may be is better for the optimised one.