Modelling and prototyping of aeronautical planetary gear demonstrator

The article presents methodology of modelling and prototyping process for the demonstrator of aeronautical planetary gear. Contemporary methods of designing gear make use of computer aided designing systems (CAD), computer aided engineering (CAE) and computer aided manufacturing (CAM) including also rapid prototyping (RP). First stage of designing gear is always defining basic parameters of the gear work (among others: transmission ratio, rotational speed, power) determined by the gear destination. After carrying out the gear calculations it is possible to create 3D-CAD models ofwheels and other elements of the gear. 3D-CAD systems are often equipped with a module for analysing geometrical parameters and cooperation of its individual elements e.g. the track of cooperation. A detailed analysis of cooperation of gear wheels' elements allows for early detection of construction mistakes of models and for deleting the mistakes. If 3D-CAD models are made correctly, it is possible to record the geometrical data in an appropriate format of numerical data. The following stage of making the prototype of the gear is preparing numerical data necessary for making the demonstrator by means of rapid prototyping method. The accuracy of making physical prototype depends a lot on the accuracy of 3D-CAD/3D-RP model made by means of processing the numerical data. The demonstrator allows for analysis of constructional solutions of the gear based on physical model and for doing introductory stand tests. The paper presents the process of making the demonstrator of planetary gear applying 3D-CAD modelling and Rapid Prototyping. For making the physical prototype a Fused Deposition Modelling (FDM) method of Rapid Prototyping was applied.