Search

Uporabniški vmesnik je sistem, ki združuje vhodne in izhodne naprave ter ostalo strojno in programsko opremo, da uporabniku omogoči kar se da eno- stavno in intuitivno komunikacijo z napravo. V tem diplomskem delu sem opisal razvoj celotnega uporabniškega vmesnika za dirkalnik tekmovanja For- mula Student. Formula Student je letno mednarodno študentsko inženirsko tekmovanje, na katerem študentje dirkajo z dirkalniki v stilu formule, ki so jih razvili in izdelali tekom šolskega leta. V armaturno ploščo in volan dirkal- nika smo vgradili plošči tiskanega vezja z mikrokrmilnikoma STM32, zaslon LCD, gonilniško ploščo za LCD Adafruit RA8875 in druge vhodno/izhodne naprave. Za gradnjo vgrajene programske opreme sem uporabil metodo in- krementalnega razvoja, integrirano razvojno okolje STM32CubeIDE in raz- hroščevalnik SEGGER J-Link. A user interface is a system consisting of input/output devices, other hardware devices and software that provides the user an easy and in- tuitive interaction with a device. In this thesis, I described the development of the entire user interface for the race car of the Formula Student compe- tition class. Formula Student is an annual international engineering design competition for university students, in which teams design, build, and race their own formula-style race cars. For the user interface system, we installed two custom printed circuit boards with STM32 microcontrollers, LCD screen, Adafruit RA8875 driver board and other I/O devices into the car’s dashboard and steering wheel. For the embedded software, I used the incremental devel- opment method, the STM32CubeIDE and the SEGGER J-Link debugger.

Avtomobili z notranjim izgorevanjem ustvarjajo različne hrupe, hrup izpušne cevi je med njimi najglasnejši. Potrebno je izvedeti, kakšne doprinose k dušenju zvoka imajo različni dušilni elementi celotnega izpušnega sistema in jih nato predelati in dodelati z uporabo simulacijskih orodij ter tako preveriti zvočno raven in padec le-te skozi celoten sistem. Pregledu celotne teoretične osnove izpušnih komponent in njihovega delovanja sledi preizkus v fizični obliki s pomočjo merilnih orodij nato pregled trenutno vgrajenih elementov sistema in predstavitev možnih nadgradenj ter udejanjanje teh v simulacijah. S pomočjo računalniških orodij primerjamo rezultate predelav s trenutnim izpušnim sistemom ter prikažemo primerjavo zvočne ravni simulacije in meritev in opredelimo verodostojnost tovrstne simulacije in morebitno nadaljnjo uporabo pri razvijanju izpušnih sistemov. Internal combustion automobiles produce a variety of noises, the loudest of which is the exhaust pipe noise. It is necessary to find out the contribution to sound attenuation of different silencing elements of the whole exhaust system and then to process and/or refine them using simulation tools to check the sound level and its drop through the whole system. An overview of the overall theoretical basis of exhaust components and their operation is followed by a physical test using measurement tools, then an overview of the currently installed system components and a presentation of possible upgrades and their implementation in simulations. Using computer aided tools, we compare results of the conversions with the current exhaust system and show the comparison betweeen simulated and physically measured noise levels to determine the validity of such simulations and possible further use in exhaust development.

Varnost dirkačev, športnih funkcionarjev in gledalcev se je skozi čas spreminjala. Če smo še pred leti lahko zabeležili ogromno smrti med gledalci ali dirkači, se je statistika v zadnjih letih znatno izboljšala. Na varnost dirkačev vpliva ogromno faktorjev, največji faktorji pa so zagotovo sestavni deli varnostne opreme v avtomobilih ter uporaba osebne varovalne opreme dirkačev. Skozi leta se je tehnologija razvijala, obenem pa so se razvijali tudi varnostni elementi. Rally spada med avto moto šport in kot vsak drugi šport je lahko nevaren vendar varnostni elementi znatno povečajo možnost preživetja ali pa vsaj zmanjšajo možnost nastanka hudih poškodb. Zaradi kompleksnosti športa sem se na začetku seznanil najprej s termini povezanimi z dirkami, nato pa z uradniki, ki jih imenujemo športni funkcionarji. Za vsakega športnega funkcionarja sem opisal njegove naloge in zadolžitve. Najpomembnejši dokument, ki je pomemben pri načrtovanju dirk je varnostni načrt – v motošportu ga imenujejo biblija med organizatorji. Varnostni načrt določa vse nevarnosti, ki bi se lahko pripetile med izvedbo dirko, prav tako pa določa število in pozicijo uradnih oseb, ki so prisotni ob trasi hitrostne preizkušnje. Ugotavljal sem pomen nesreče na dirkah in postopke v primerih dirkaške nesreče. Najpomembnejši del pa je bil požar, pri čemer sem mogel najprej ugotoviti vzroke za nastanek požara v dirkalnikih. Za preprečevanje požara se uporabljajo naslednji varnostni elementi: gasilni aparati, centralni gasilni sistem, varnostni rezervoar, požarna stena ter obloge na varnostni kletki. Dirkače pred plameni varuje osebna oprema – podkapa, kombinezon, spodnje perilo, nogavice ter rokavice. Vsak del opreme, ki je vgrajen v vozilu ali osebna oprema dirkača mora biti izdelan po strogih navodilih FIA, obenem pa je potrebno upoštevati tudi FIA standard. Dirkač na dirki ne sme nastopiti, če vsa oprema ni homologiran. Opremo se vedno preveri pred začetkom dirke oziroma na tehničnem pregledu. Rally v Sloveniji žal ni najbolj prepoznaven šport, za kar pa obstaja cel kup dejavnikov. Diplomsko delo sem poskusil sestaviti na takšen način, da se bralcu na najboljši možen način predstavi organizacijski del, seznani z dokumenti, ki so pomembni za varno organizacijo dirk ter podrobneje spozna varnostne elemente tako dirkalnika kakor dirkača. The safety of racers, racing sports functionaries and observers of the sport has been changing constantly over time. If only a few years ago many deaths were recorded between racers and race fans alike, the statistics of these events happening have lowered significally. A lot of factors concerning safety must be taken into account with the races and their participants, the most prominent of which are the safety components of the cars themselves and the racers' body safety gear. Through the years as automobile technology advanced the advancement of these safety elements also played a crucial part in protecting the participants of races. Rally is a part of the auto-moto sport family and as such can be very dangerous, but the afforementioned safety elements highly increase the chances of survival or, at the very least, prevent heavy bodily injuries. Because of the complexity of the sport I first got familiar with the terminology concerning racing and then the officials we call racing sports functionaries. For every one of these functionaries I explained his role in the sport - meaning his duties and assignments. The most important document needed when planning a race is the safety document - between organisers in motosports it is called "the bible". It defines any and all dangerous events that might occur during the duration of the race, while also defining the number and position of safety personnel, who are also present during the speed test of the track. I also researched the meaning of accidents on races and the actions taken upon one occuring. The most important part though were possible fires, where I had to find out the reasons for their occurence in race cars. For fire prevention the following safety elements are used: fire extinguishers, central fire prevention systems, safety reservoirs, firewalls and the lining of the safety cages of race cars. The racers themselves are protected by their personalised safety equipment - an undercap, the racing suit itself, proper socks and proper gloves. Every piece of equipment in the car or the racers' personalised equipment must follow the rules of the FIA and meet FIA standards. A racer can't perform on a race if all equipment isn't homologated. The equipment is always checked before the race or on the vehicles' technical reviews. Rally racing sadly isn't a very recognised sport in Slovenia, having many contributing factors. This thesis was designed in a way that could present the reader many different elements of racing in the best way possible, from the organisation part to the documents needed to safely organise these races and an in-depth insight into the personalised safety equipment of race cars and the drivers themselves.

Zaključna naloga predstavlja razvoj premnika dirkalnika Formule Student, ki je pomemben del sestava kolesa, saj povezuje glavne dele podvozja s komponentami kolesnega sestava, kot so pesto, zavorni diski, zavorne čeljusti in navsezadnje s samim kolesom. Glavni cilj je razviti premnike, ki bodo zagotavljali čim boljše rezultate na tekmovanjih in bili v skladu s podanim pravilnikom tekoče sezone. Pri zasnovi smo zato upoštevali vse omejitve pravilnika z ozirom na čim lažje komponente, kar izboljšuje vozno dinamiko vozila. Zanesljivost komponent pa smo določili z detajlnim modeliranjem koncepta in določitvijo sil, ki delujejo na kolesni sestav med vožnjo, kar smo na koncu uporabili za dodatno numerično analizo po metodi končnih elementov (MKE). The thesis presents the development of the Formula Student car uprights. Uprights are an important part of the wheel assembly, as they connect the main suspension parts with the main wheel assembly components, such as wheel hub, braking discs, brake calipers and eventually the wheel itself. The main objective is to develop an upright, that will ensure the best possible results on the competition and is made in complience with the provided regullations for the current year. In design phase we took in considerations all limitations of the rulebook with desire for light components and as such improve the driveability of the race car. The reliability was achieved through detailed design, based on the determined forces on wheel assembly, which was then used for further numerical analysis with the finite element method.

V diplomskem delu je predstavljeno konstruiranje blažilca trkov iz aluminijastega satovja s pomočjo dinamičnih numeričnih analiz za dirkalnik Formula Student. Predstavljeno je kalibriranje materialnih podatkov s pomočjo rezultatov opravljenega tlačnega preizkusa. S pomočjo teh materialnih podatkov je bilo kasneje izvedenih več dinamičnih računalniških simulacij trka, in sicer za dve različni izvedbi blažilca trkov. Za ta dva različna tipa blažilca trkov sta bila kasneje izvedena tudi praktična preizkusa oz. testna trka pri predpisanih testnih pogojih. Na podlagi rezultatov testnega trka je bil izbran končni blažilec trkov, ki izpolnjuje vse zahteve pravilnika »Formula SAE Rules«. In my diploma thesis, I have presented, using dynamic numerical analyses, the designing of impact attenuators constructed out of aluminium honeycomb made for the Formula Student race car. I have presented the calibration of the data on the material’s properties using the results of the pressure test that was carried out. Using the data on the material’s properties, several dynamic computer crash simulations were carried out, namely for two different versions of the impact attenuators. These two types of impact attenuators were later also put through practical tests – crash tests according to the test conditions. Based on the crash test results an impact attenuator was selected that fulfils all the requirements listed in the Formula SAE Rules.

Po preteklem tekmovanju z dirkalnikom GPE11 smo se odločili za uporabo merilnega sistema, s katerim smo bolj optimalno nastavili dirkalnik in se posledično na tekmovanjih z dirkalnikoma GPE12 in GPE13, kljub napredku konkurence, uvrščali na višja mesta. Predstavljen je izbor merilnih veličin, osnovni principi delovanja senzorjev in določitev le-teh. Ti so povezani v celoto preko merilnega sistema, ki vsebuje prenos podatkov v živo. S tem smo se že med samim testiranjem lahko odločali o naslednjih korakih. S pridobljenimi podatki smo analizirali vožnjo voznikov ter jim preko tega svetovali, kje je moč pridobiti čas. After the competition with racecar GPE11 we have decided to use a measuring system, with which we could improve performance of the car on the competition. With race car data acquisition system we have improved our scoring on the competition with race cars GPE12 and GPE13. Choosing the right measuring parameters, basic working principles and the way how to choose sensors are described. Those sensors are connected into data acquisition system, which also includes sending live data into the pits. With this system we are able to decide about our next steps already during the testing session With all the collected data we also analyse drivers performance.

Na podlagi pravilnika Formula SAE se določijo zmogljivosti dirkalnika, ki bodo na tekmovanju prinesle čim boljši rezultat. Predstavljene so osnovne lastnosti pnevmatik in osnove dinamike vozil. Predstavljeni so modeli dinamike vozila v zavoju od točkovnega do štirikolesnega z nelinearnim modelom pnevmatike, ki pokažejo vpliv osnovnih parametrov vzmetenja vozila na zmogljivosti. Obravnavane so kinematične in dinamične lastnosti vzmetenja z dvojnimi A-rokami. Predstavljen je model prenosa sile teže v zavoju glede na lastnosti vzmetenja. Podane so priporočljive okvirne vrednosti osnovnih parametrov za začetek konstruiranja dirkalnika Formula Student. Predstavljena je metodologija konstruiranja vzmetenja z dvojnimi A-rokami s ciljem doseganja zahtevanih lastnosti. Following the analysis of Formula SAE rules the performance of the car that will score the most points at the competition are defined. Basic properties of tires and basics of vehicle dynamics are discussed. Models of car's dynamics during cornering from simple point model to four wheel model with non-linear tyre properties are described. Those models show the impact of basic vehicle parameters on its performance. Kinematic and dynamic properties of double wishbone suspension are discussed. Model of dynamic weight transfer during cornering is described. Approximate values of basic suspension parameters appropriate for Formula Student car are defined. A methodology of a double wishbone suspension design with a goal of achieving the desired performance is described.

V diplomski nalogi je predstavljen začetni razvoj kolesa izdelanega iz kompozitnega materiala, ogljikovih vlaken prepojenih z epoksidno smolo, za dirkalnik razreda Formula Student. Predstavljene so splošne informacije o kompozitih z urejenimi kontinuiranimi vlakni v polimerni matrici. V namen numerične simulacije so izdelani linearno elastični materialni modeli treh vrst kompozita iz različnih tkanin ogljikovih vlaken z nateznimi preizkusi. Z numerično analizo je določena razporeditev in orientacija plasti kompozita po kolesu, s kriterijem togosti kolesa. Deloma je določena trdnost kolesa, po kriteriju porušitve plasti Tsa-Hill. Predstavljene so možnosti za nadaljevanje razvoja, do končnega izdelka. In this diploma thesis an initial development phase of Formula Student race car wheel, made out of carbon fiber-epoxy composite is presented. General information on fiber reinforced plastic composites is given. For the purpose of numerical simulations, three linear elastic material models of different carbon fabrics with the same matrix were made with tensile tests. With the numerical analysis the ply layup on the wheel was determined with the use of wheel stiffness requirements. Strength is partially determined with the use of Tsai-Hill ply failure criterion. Possibilities on further development to the final product are presented.