Abstract: A method for designing a gearset meeting one or more design targets is provided. In particular, the design target is efficiency. Initially, a size and ratio of the gear set is specified. Gear friction coefficients are then calculated, and a value for a design target for the gear set is calculated. One or more of the macro-geometry parameters are modified, and the macro-geometry parameters are chosen such that the advantageous effects of one macro-geometry parameter on the design target counteract any disadvantageous effects of another macro-geometry parameter. This allows for a design for a gearset meeting the one or more design targets to be produced. The efficiency calculation includes the effect of a lubricant. Further design targets can include gear noise and gear durability.

Abstract: A computer-implemented method for modelling a driveline. The driveline comprising a plurality of components. The method comprising the steps of: a) receiving a parametric description of the driveline; b) creating a tribology model of the driveline from the parametric description; c) calculating one or more traction coefficients for one or more components of the driveline using the tribology model; and d) calculating a performance metric of the driveline, based on the parametric description and the one or more traction coefficients.

Abstract: A method for designing a gearset meeting one or more design targets is described. In particular, the design target is efficiency. Initially, a size and ratio of the gear set is specified. Gear friction coefficients are then calculated, and a value for a design target for the gear set is calculated. One or more of the macro-geometry parameters are modified, and the macro-geometry parameters are chosen such that the advantageous effects of one macro-geometry parameter on the design target counteract any disadvantageous effects of another macro-geometry parameter. In this way, a design for a gearset meeting the one or more design targets is produced. The efficiency calculation includes the effect of a lubricant. Further design targets can include gear noise and gear durability.

Abstract: A method for designing a planetary gearset meeting one or more design targets is described. Initially, a size and ratio of the planetary gear set, and the number of planet gears for the planetary gearset is specified. All valid combinations of tooth numbers and planet numbers that satisfy one or more constraints are then calculated. From these, a starting combination is selected and a value for a design target for the gear set is calculated. One or more of the macro-geometry parameters are modified, and the macrogeometry parameters are chosen such that the positive effects of one macrogeometry parameter on the design target counteract any negative effects of another macrogeometry parameter. In this way, a design for planetary gearset meeting the one or more design targets is produced. Also disclosed is a method additionally calculating a sideband distribution resulting from the selected combination.