My first project was to generate a full transmission Bill Of Materials (BOM) with estimated weights calculated by Siemens NX which would later be compared with actual measured values. In order to accomplish this I first used the Project Lifecycle Management (PLM) software to retrieve the weight data from the CAD models by inputting specific manufacturing codes to retrieve the correct components lists. I exported these BOM’s to excel and filtered them using a combination of built in Excel filtering tools and custom visual basic Excel macros. The data from these excel files was used to compare full transmission weights with previously weighed transmissions to determine the accuracy of NX weight estimates. The next step in the weight audit project was to compare individual component weights. This involved both further generation of more detailed BOM’s for a specific transmission which we would be weighing at a later date as well as generation of a data entry spreadsheet using further VBA macros. The data entry sheet uses action buttons which the user presses to bring up a menu to input a part number, description, and mass of the component. It also incorporates a lookup function which allows the user to search an available BOM and return the currently recorded weight as well as the part name and description to reduce errors in the recording process. This tool allowed for rapid data recording and allowed the team and I to record the mass of every component in a transmission in a few hours.
In addition to the larger long term weight audit project, I was also working on a number of tolerance stackup calculations for the upcoming 2020 transmission. These were done using an Excel spreadsheet previously created by the team as well as reading of technical drawings of the components used in the calculations. One example of a calculation completed was axial position tolerance and play of the full gear set for the 2020 transmission including both the gears on both the main and counter shafts as well as the reverse idler gear. Other calculations completed included radial play in the main bearings due to variance in counter shaft angle, axial play in the countershaft brake discs and others.