Baigiamajame darbe nagrinėjamos visureigio automobilio dinaminės charakteristikos bei pagrindiniai jas lemiantys parametrai, ieškoma būdų šių parametrų pagerinimui. Taip pat darbe apžvelgiamos automobilį veikiančios jėgos, apžvelgiama automobilio masės bei įkrovos lygio įtaka automobilio dinamikai, priekabos įtaka automobilio stabilumui bei valdomumui. Atlikus eksperimentinius visureigio automobilio kėbulo svyravimų bandymus priklausomai nuo: priekabos įkrovos, kelio dangos, bei transporto priemonės ir transporto priemonių junginio greičio gauti rezultatai išanalizuoti ir palyginti tarpusavyje. Pateikiami skaitinius bandymų rezultatus atitinkantys grafikai. Išvadose apibendrinami tyrimo rezultatai. / This master thesis analysis dynamic characteristics of all – terrain vehicle, main parameters having impact on them, searches for ways to improve them. The paper also reviews the forces operating on the vehicle, reviews the impact of the vehicle’s weight and the level of load on the dynamics of the vehicle, the influence of a trailer on the stability and controllability of the vehicle. The results of the experimental tests of all – terrain vehicles body’s swinging were analyzed and compared. The charts depicting numeric results of tests are provided. The conclusions summarize the results of the research.

Nowadays disabled persons are actively integrated into social life and different compensatory equipment allows them to work and travel independently. The wheelchair is one of such means; it provides mobility function for physically impaired persons. Not every disabled person has possibilities to travel by his own car, it is more convenient to use public transport facilities. Wheelchair users' transportation safety is one of the most important problems facing transit providers and engineers. Improperly or totally unsecured wheelchair can lose the stability and tip over during the emergency driving situations and result in passenger falling and becoming injured. The main object of the scientific research work is complex dynamic system "Man - Wheelchair - Vehicle", which is under action of environmental factors (road roughness, motion oscillations of vehicle). The main tasks of the work are to form and research non-linear model of dynamic system considered, to define system's stability limits and to provide means for save travel. Also to determine main characteristics of the external action and analyze its influence on to considered system; to build engineering computation methodology for estimation of the rational parameters to fasten the wheelchair to the vehicle.

Įvairių sričių reiškinių matematiniai modeliai apima daug faktorių, kurie yra priklausomi nuo laiko, o taip pat pastebima jų tarpusavio priklausomybė. Vadinasi, norint nagrinėt šių reiškinių kitimo dėsnius, patartina sudaryti šių procesų dinaminį modelį. Šiame darbe dinaminio modelio sudarymui naudojami indikatoriai. Indikatorius tai specialus rodiklis, kuriuo pasinaudojus galima skaitiškai įvertinti svarbius analizuojamos srities faktorius. Indikatorių reikšmės gaunamos iš statistinių duomenų. Diferencialinių lygčių sistemos koeficientams skaičiuoti pristatomi du būdai: algebrinis ir mažiausių kvadratų metodai. Indikatorių išraiškas, gautas išsprendus diferencialinių lygčių sistemą, galima panaudoti prognozavimui. Tačiau įgyvendinant naujus projektus, šias indikatorių išraiškas reikia patikslinti, atsižvelgiant į naujus faktorius. Kadangi naujų faktorių reikšmės nėra tiksliai žinomos (gautos iš ekspertinio vertinimo), jų įtaka sistemai yra išreiškiama atsitiktiniu dydžiu su žinomu tikimybiniu skirstiniu. Naujų faktorių įtaka indikatoriams dinaminiame modelyje yra patikslinama Bajeso metodu. Kaip pavyzdys, sudarytas dinaminis modelis pritaikytas energijos tiekimo saugumo indikatorių modeliavimui. / In many areas mathematical models of processes take into acount variuos time dependent factors, they also can be dependent on each other. Thus, it is advisable to construct a dynamic model. In this master thesis we use indicators to describe dynamic model. An indicator is a special index, which provides numerical values to inportant factors for the investigated sector. The values of indicators are obtained from statistical data. There are presented two calculation ways of differential equations systems coefficients (using algebraic and least square methods). Furthermore created dynamic model enables us to forecast the dynamics of the indicators according to new factors. Since the parameters of different new factors are not exactly known (got from expert judgement), their influence on indicators are expressed as random variables with known probablistic distributions. Indicators model based on historical data is adjusted using a Bayesian approach. For practical demonstration of the proposed dynamic model energy security assessment indicators were chosen.

Nowadays disabled persons are actively integrated into social life. Different compensatory equipment allows them to work and travel independently and one of such means is the wheelchair. Not every disabled person has possibilities to travel by his own car, it is more convenient to use public transport facilities. Transportation safety of the wheelchair users is one of the most important problems facing engineers and transit providers, becouse improperly or totally unsecured wheelchair can lose the stability and tip over during the emergency driving situations. The main object of the scientific research work is complex dynamic system "Man - Wheelchair - Vehicle", whis is under action of environmental factors (road roughness, motion oscillations of vehicle). The main tasks of the work are to form and research nonlinear model of dynamic system considered and to define system's stability limits, providing means for safe travel; to determine main characteristics of the external action and analyze its influence on to dynamic system; to build engineering computation methodology for estimation of the rational parameters to fasten the wheelchair to the vehicle.