Autoralli võistlussõiduki käigukasti projekteerimine

Lõputöö käigus pöördprojekteeriti XShift poolt loodud Audi S1 käigukasti võllid ja hammasrattad. Pöördprojekteeritud hammasratastele teostati erinevad analüüsid kasutades KISSsoft tarkvara ning seejärel leiti uued profiilid. Suurema osa käikude puhul saavutati eeldatav eluiga neli aastat. Lisaks eluea pikenemisele vähendati kontaktitemperatuure kuni 40 kraadi võrra ja suurendati varutegureid kuni 1,5 võrra. Võllide analüüsidest selgus, et korpust tuleks jäigemaks teha, selleks pakuti välja variant kasutada laagripesades terasest hülsse. Laagrite analüüsidest järeldati, et eelnevad laagrid olid sobiliku mõõduga, kuid võllide paindedeformatsioon on ideaalist suurem. Võllide läbipainde vähendamiseks esitas autor idee vähendada võlli ja võlli peal asetsevate komponentide vahelist lõtku. Projekti rahaline maksumus tellimustööna oleks ligi 60% kallim kui uue käigukasti ostmine, kuid analüüside põhjal kestaks uus käigukast kauem kui esialgne. Kuna ajalise puudujäägi tõttu jäid korpused projekteerimata, on see võimalus projekti edasi arendada, saavutamaks täielikult nelja hooaja pikkune eluiga.

It is largely common in motorsports for the engines of the racing vehicles to have been developed towards higher capacity. While using a modified engine, the gearbox must withstand the torque the engine develops. A similar problem occurs with the Audi S1 8X adapted for EMV class 1. This car has a maximum transmission life of two seasons, after which most of the transmission must be replaced. The following thesis Designing the Gearbox of a Racing Vehicle aims to find, based on the faults of the existing gearbox, which components need to be strengthened, so that the aforementioned gearbox of the Audi S1 8X lasts for four seasons instead of two, as requested by the customer. The key aspect for this project was to preserve the original clutch housing, gear shifting mechanism and gear ratios. Components of the gear box were scanned using the The 3D scanner Creaform GO!SCAN Spark situated in Tallinn University of Technology. 3D scanning was the optimal choice for measuring the components quickly and accurately. Based on the scanned model, a 3D model was created from the details using Autodesk Inventor CAD software. The analogues for the scanned gears were created using the software KISSsoft. Various analyses were performed on the profile of the primary gears in order to find out whether the life of the gears could be increased. For analysis, the author combined load spectra for all gears based on log data obtained from the 2022 Rapla rally event, where the Audi S1 8X was competing. After analysing the gears, the displacement and equivalent stress analysis of the shafts were also carried out using the program KISSsys. Finally, the approximate cost of designing the gearbox for the competition vehicle was calculated for both the client and the company. The first chapter of the thesis presents the current situation, identifies the errors, and describes the workflow of reverse engineering. The second chapter describes the process of creating the background information necessary for gear analysis and how the rest of the analyses were carried out. The chapter also describes the principles of determining tolerances and finally presents the calculation of the price for the customer as well as the net cost based on the hours worked on the project. The author initially planned to also carry out analyses relating to the new housing, but due to the large volume of the project, the analyses where only performed on the designs of the gears and shafts.