1,273 research outputs found
ΠΠ± ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠΈ ΡΠΈΠ» ΡΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ ΠΊΠΎΠ»Π΅Ρ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π°, ΠΎΠ±ΠΎΡΡΠ΄ΠΎΠ²Π°Π½Π½ΠΎΠ³ΠΎ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΠΎΠΉ ΡΠ΅Π³ΡΠ»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠΎΡΠΌΠΎΠ·Π½ΠΎΠ³ΠΎ ΡΡΠΈΠ»ΠΈΡ
The paper considers a method for calculation and evaluation of an automated brake proportioning system and it also describes assessment of efficiency while using cohesion forces of an automated system during vehicle braking process (MAZ 256200 taken as an example). A method for efficiency estimation of the vehicle braking equipped with an automated brake proportioning system is graphically presented in the paper. A comparable analysis has been made in order to evaluate vehicle braking efficiency in three various conditions of its wheel motion during braking process. The paper contains description of braking processes for a vehicle at its idealized braking, at braking with an operating automated system and at braking with blocked wheels. Mathematical dependences have been proposed and they make it possible to calculate a coefficient of cohesion forces used by an automated brake proportioning system on the basis of time parameters for vehicle braking process. The proposed mathematical dependences take into account design peculiarities of the automated system, i.e. a diagram of modulator arrangement on axes of the vehicle. The executed analysis for calculation accuracy of the coefficient pertaining to use of cohesion forces of the automated system with and without taking into accout rolling force resistance of the vehicle wheels has demonstrated a possibility to apply the proposed calculation methods for carrying out auto-technical expertise while investigating road-traffic accidents involving transport facilities equipped with such systems as ABS. The paper proposes a dependence for identification of a vehicle braking distance on the basis of the coefficient on use of cohesion forces by the automated brake proportioning system. The executed experimental investigations on both test and serial models of the automated brake proportioning system have allowed to justify theoretical discussions concerning application of tyre-road adhesion in the operational process of the vehicle brake proportioning system. The investigation results have shown high efficiency of the test automated brake proportioning system developed by Chair of Automobiles in the name of A. B. Hredescul at Kharkiv National Automobile and Road University under the following braking conditions: dry road surface and compacted snow cover.Π ΡΡΠ°ΡΡΠ΅ ΡΠ°ΡΡΠΌΠΎΡΡΠ΅Π½ ΠΌΠ΅ΡΠΎΠ΄ ΡΠ°ΡΡΠ΅ΡΠ° ΠΈ ΠΎΡΠ΅Π½ΠΊΠΈ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ ΡΠ΅Π³ΡΠ»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠΎΡΠΌΠΎΠ·Π½ΠΎΠ³ΠΎ ΡΡΠΈΠ»ΠΈΡ, Π° ΡΠ°ΠΊΠΆΠ΅ Π²ΡΠΏΠΎΠ»Π½Π΅Π½Π° ΠΎΡΠ΅Π½ΠΊΠ° ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΠΈ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ ΡΠΈΠ»Ρ ΡΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΠΎΠΉ Π² ΠΏΡΠΎΡΠ΅ΡΡΠ΅ ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΡ ΠΊΠΎΠ»Π΅ΡΠ½ΠΎΠ³ΠΎ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π° (Π½Π° ΠΏΡΠΈΠΌΠ΅ΡΠ΅ Π°Π²ΡΠΎΠ±ΡΡΠ° ΠΠΠ 256200). ΠΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΈ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½ ΠΈ ΠΎΠ±ΠΎΡΠ½ΠΎΠ²Π°Π½ ΡΠΏΠΎΡΠΎΠ± ΠΎΡΠ΅Π½ΠΊΠΈ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΠΈ ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΡ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π°, ΠΎΠ±ΠΎΡΡΠ΄ΠΎΠ²Π°Π½Π½ΠΎΠ³ΠΎ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΠΎΠΉ ΡΠ΅Π³ΡΠ»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠΎΡΠΌΠΎΠ·Π½ΠΎΠ³ΠΎ ΡΡΠΈΠ»ΠΈΡ. ΠΡΠΎΠ²Π΅Π΄Π΅Π½ ΡΡΠ°Π²Π½ΠΈΡΠ΅Π»ΡΠ½ΡΠΉ Π°Π½Π°Π»ΠΈΠ· ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΠΈ ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΡ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π° Π² ΡΡΠ΅Ρ
ΡΠ°Π·Π½ΡΡ
ΡΡΠ»ΠΎΠ²ΠΈΡΡ
Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ Π΅Π³ΠΎ ΠΊΠΎΠ»Π΅Ρ ΠΏΡΠΈ ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΠΈ. ΠΠΏΠΈΡΠ°Π½Ρ ΠΏΡΠΎΡΠ΅ΡΡΡ ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΡ ΠΏΡΠΈ ΠΈΠ΄Π΅Π°Π»ΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΌ ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΠΈ, ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΠΈ ΠΏΡΠΈ ΡΠ°Π±ΠΎΡΠ΅ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ, Π° ΡΠ°ΠΊΠΆΠ΅ ΠΏΡΠΈ ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΠΈ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π° Ρ Π·Π°Π±Π»ΠΎΠΊΠΈΡΠΎΠ²Π°Π½Π½ΡΠΌΠΈ ΠΊΠΎΠ»Π΅ΡΠ°ΠΌΠΈ. ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Ρ ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΠΈ, ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡΡΠΈΠ΅ ΡΠ°ΡΡΡΠΈΡΠ°ΡΡ ΠΊΠΎΡΡΡΠΈΡΠΈΠ΅Π½Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ ΡΠΈΠ»Ρ ΡΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΠΎΠΉ ΡΠ΅Π³ΡΠ»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠΎΡΠΌΠΎΠ·Π½ΠΎΠ³ΠΎ ΡΡΠΈΠ»ΠΈΡ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ Π²ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠΎΠ² ΠΏΡΠΎΡΠ΅ΡΡΠ° ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΡ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π°. ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Π½ΡΠ΅ ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΠΈ ΡΡΠΈΡΡΠ²Π°ΡΡ ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠΈ ΠΊΠΎΠ½ΡΡΡΡΠΊΡΠΈΠΈ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ, Ρ. Π΅. ΡΡ
Π΅ΠΌΡ ΡΠ°ΡΠΏΠΎΠ»ΠΎΠΆΠ΅Π½ΠΈΡ ΠΌΠΎΠ΄ΡΠ»ΡΡΠΎΡΠΎΠ² Π½Π° ΠΎΡΡΡ
ΠΊΠΎΠ»Π΅ΡΠ½ΠΎΠ³ΠΎ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π°. ΠΡΠΏΠΎΠ»Π½Π΅Π½Π½ΡΠΉ Π°Π½Π°Π»ΠΈΠ· ΡΠΎΡΠ½ΠΎΡΡΠΈ ΡΠ°ΡΡΠ΅ΡΠΎΠ² ΠΊΠΎΡΡΡΠΈΡΠΈΠ΅Π½ΡΠ° ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ ΡΠΈΠ»Ρ ΡΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΠΎΠΉ Ρ ΡΡΠ΅ΡΠΎΠΌ ΠΈ Π±Π΅Π· ΡΡΠ΅ΡΠ° ΡΠΈΠ» ΡΠΎΠΏΡΠΎΡΠΈΠ²Π»Π΅Π½ΠΈΡ ΠΊΠ°ΡΠ΅Π½ΠΈΡ ΠΊΠΎΠ»Π΅Ρ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π° ΠΏΠΎΠΊΠ°Π·Π°Π» Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΡ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ ΠΏΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Π½ΡΡ
ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ² ΡΠ°ΡΡΠ΅ΡΠ° Π² ΠΏΡΠ°ΠΊΡΠΈΠΊΠ΅ Π°Π²ΡΠΎΡΠ΅Ρ
Π½ΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠΊΡΠΏΠ΅ΡΡΠΈΠ· ΠΏΡΠΈ ΡΠ°ΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠΈ Π΄ΠΎΡΠΎΠΆΠ½ΠΎ-ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΡΡ
ΠΏΡΠΎΠΈΡΡΠ΅ΡΡΠ²ΠΈΠΉ Ρ ΡΡΠ°ΡΡΠΈΠ΅ΠΌ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΡΡ
ΡΡΠ΅Π΄ΡΡΠ², ΠΎΠ±ΠΎΡΡΠ΄ΠΎΠ²Π°Π½Π½ΡΡ
ΡΠ°ΠΊΠΈΠΌΠΈ ΡΠΈΡΡΠ΅ΠΌΠ°ΠΌΠΈ, ΠΊΠ°ΠΊ ABS. ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Π° Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΡ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΡΠΎΡΠΌΠΎΠ·Π½ΠΎΠ³ΠΎ ΠΏΡΡΠΈ ΠΊΠΎΠ»Π΅ΡΠ½ΠΎΠ³ΠΎ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π° Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΊΠΎΡΡΡΠΈΡΠΈΠ΅Π½ΡΠ° ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ ΡΠΈΠ»Ρ ΡΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΠΎΠΉ ΡΠ΅Π³ΡΠ»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠΎΡΠΌΠΎΠ·Π½ΠΎΠ³ΠΎ ΡΡΠΈΠ»ΠΈΡ. ΠΡΠΏΠΎΠ»Π½Π΅Π½Π½ΡΠ΅ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΠΎΠΏΡΡΠ½ΠΎΠ³ΠΎ ΠΈ ΡΠ΅ΡΠΈΠΉΠ½ΠΎΠ³ΠΎ ΠΎΠ±ΡΠ°Π·ΡΠΎΠ² Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ ΠΏΠΎΠ·Π²ΠΎΠ»ΠΈΠ»ΠΈ ΠΏΠΎΠ΄ΡΠ²Π΅ΡΠ΄ΠΈΡΡ ΡΠ΅ΠΎΡΠ΅ΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΡΠ°ΡΡΡΠΆΠ΄Π΅Π½ΠΈΡ Π² ΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΠΈ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ ΡΠΈΠ» ΡΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ Π² ΠΏΡΠΎΡΠ΅ΡΡΠ΅ ΡΠ°Π±ΠΎΡΡ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ ΡΠ΅Π³ΡΠ»ΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠΎΡΠΌΠΎΠ·Π½ΠΎΠ³ΠΎ ΡΡΠΈΠ»ΠΈΡ ΠΊΠΎΠ»Π΅ΡΠ½ΠΎΠ³ΠΎ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π°. Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠΉ ΠΏΠΎΠΊΠ°Π·Π°Π»ΠΈ Π²ΡΡΠΎΠΊΡΡ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ ΡΠ°Π±ΠΎΡΡ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΠΎΠΉ Π°Π²ΡΠΎΠΌΠ°ΡΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ, ΡΠ°Π·ΡΠ°Π±ΠΎΡΠ°Π½Π½ΠΎΠΉ Π½Π° ΠΊΠ°ΡΠ΅Π΄ΡΠ΅ Π°Π²ΡΠΎΠΌΠΎΠ±ΠΈΠ»Π΅ΠΉ ΠΈΠΌΠ΅Π½ΠΈ Π. Π. ΠΡΠ΅Π΄Π΅ΡΠΊΡΠ»Π° Π₯Π°ΡΡΠΊΠΎΠ²ΡΠΊΠΎΠ³ΠΎ Π½Π°ΡΠΈΠΎΠ½Π°Π»ΡΠ½ΠΎΠ³ΠΎ Π°Π²ΡΠΎΠΌΠΎΠ±ΠΈΠ»ΡΠ½ΠΎΠ΄ΠΎΡΠΎΠΆΠ½ΠΎΠ³ΠΎ ΡΠ½ΠΈΠ²Π΅ΡΡΠΈΡΠ΅ΡΠ°, Π² ΡΡΠ»ΠΎΠ²ΠΈΡΡ
ΡΠΎΡΠΌΠΎΠΆΠ΅Π½ΠΈΡ ΡΡΠ°Π½ΡΠΏΠΎΡΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅Π΄ΡΡΠ²Π° Π½Π° ΡΡΡ
ΠΎΠΌ Π°ΡΡΠ°Π»ΡΡΠΎΠ²ΠΎΠΌ ΠΈ ΡΠΊΠ°ΡΠ°Π½Π½ΠΎΠΌ ΡΠ½Π΅ΠΆΠ½ΠΎΠΌ ΠΏΠΎΠΊΡΡΡΠΈΡΡ
Brake Strategy Analysis for Industrial Normal-closed Brake Based on Rotational Inertia Test and Simulation
Industrial brakes pose the dilemma of weighing brake capability against brake impact since the brake torque cannot be adjusted. On the one hand, the brake torque may be insufficient to stop the movement within a limited distance or parking position. On the other hand, the brake torque may be so high it can damage the transmission chain. In this study, the traditional brake strategy and the field oriented control (FOC) brake strategy were compared through simulation and a rotational inertia test. The influence of the rated brake torque and the open-closed ratio were obtained. Based on the test and simulation results, a semi-empirical formula that defines the relationship between relative brake capability and open-closed ratio was developed. Additional simulations were performed to analyze the performance of the brake in a flexible transmission chain. As an industrial application example, the benefits and the cost of a 'smart brake' based on the FOC brake strategy were analyzed. The results indicate that the equivalent brake torque with the FOC brake strategy is a function of the real-time controllable input and open-closed ratio, which can be conducted during the braking procedure. This can be an efficient way to solve the above problems
Chitosan-zinc oxide composite for active food packaging Applications
Chitosan-zinc oxide (C-ZnO) films were prepared by a simple one pot procedure. In order to investigate the property of C-ZnO films, two composite films were prepared by varying the loading of ZnO and compared with pure chitosan film (C). The films were character-ized by various techniques such as FTIR, DSC, tensile, contact angle and water vapour permeability. FTIR analysis showed changes in hydrogen bonds band at 3351 cm-1 compared to pure chitosan film. The incorporation of ZnO in chitosan films increased the contact angle by 30.5% in C-ZnO1.0 film while water vapour transmission rate decreased by 7.8% compared to C film. From the tensile test, C-ZnO0.5 and C-ZnO1.0 films were found to be much superior by 1.5 times and 2.5 times respectively compared to bare chitosan film. Larger inhibition ring (by 47%) was exhibited by C-ZnO1.0 as compared to C-ZnO0.5 when tested against S.aureus. From the results, it is displayed that the incorporation of zinc oxide to chitosan improve their properties which also shown the potential to become a candi-date for food active packaging
Design and Simulation Analysis for Integrated Vehicle Chassis-Network Control System Based on CAN Network
Due to the different functions of the system used in the vehicle chassis control, the hierarchical control strategy also leads to many kinds of the network topology structure. According to the hierarchical control principle, this research puts forward the integrated control strategy of the chassis based on supervision mechanism. The purpose is to consider how the integrated control architecture affects the control performance of the system after the intervention of CAN network. Based on the principle of hierarchical control and fuzzy control, a fuzzy controller is designed, which is used to monitor and coordinate the ESP, AFS, and ARS. And the IVC system is constructed with the upper supervisory controller and three subcontrol systems on the Simulink platform. The network topology structure of IVC is proposed, and the IVC communication matrix based on CAN network communication is designed. With the common sensors and the subcontrollers as the CAN network independent nodes, the network induced delay and packet loss rate on the system control performance are studied by simulation. The results show that the simulation method can be used for designing the communication network of the vehicle
STRAIGHT LINE BRAKING PERFORMANCE OF A ROAD VEHICLE WITH NON LINEAR TIRE STIFFNESS FORMULATION
The capability of a road vehicle equipped with an Anti-Lock Braking System (ABS) to come to a safe stop depends on factors such as dynamic force between tire and road, surface adhesion coefficient, and the vertical profile of the road. When in panic, a driver\u27s reaction is to step hard on the brakes to make the vehicle stop as soon as possible. Although the use of modern technologies such as ABS and Electronic Stability Control (ESC) have reduced the number of accidents significantly, any further improvement in stopping distance would only complement these technologies. Michelin has undertaken the development of a non-pneumatic tire (called the TWEELTM) which can decouple the ride comfort and handling capability of road vehicles. Studies in the ride comfort area have shown reductions in the tire-to-road dynamic force using the TWEELTM. This might lead to shorter stopping distances while braking. The primary focus area of this thesis is to evaluate the straight line braking performance of a 2007 BMW Mini Cooper with TWEELsTM on randomly irregular roads. Different vertical road profiles were utilized to evaluate their effect on braking. A comparison of results is made between the original equipment (OE) tires and the TWEELTM. Additionally, the effect on vehicle braking of tuning the shock absorbers was also studied. A eight degree-of-freedom model that focuses on vertical and longitudinal dynamics was developed in Simulink. A rather simple brake system with an ideal antilock system (ABS) was used to avoid wheel lock-up in hard braking scenarios. A Pacejka tire model was employed as well. The nonlinear tire stiffness and the nonlinear shock absorber curves were incorporated in the model using look-up tables. The model was validated in the time domain using the results from a vehicle model in CarSim for similar tests. For simulation on a road profile similar to weathered asphalt at Michelin\u27s Laurens Proving Grounds (WA-LPG), the selection between TWEELTM and OE tire does not affect braking performance. Also, the frequency content of the \u27smooth\u27 road profile had minimal effect on stopping distance. However, as RMS roughness of road profiles increased, the stopping distance increased for both the TWEELTM and the OE tire and the \u27softer\u27 TWEELTM yielded a shorter stopping distance than the OE tire. When shock damping was altered, no change in stopping distance was found on \u27smooth\u27 roads and \u27firmer\u27 shocks performed better on \u27rough\u27 road profiles
Bibliography on heavy vehicle dynamics
http://deepblue.lib.umich.edu/bitstream/2027.42/108243/1/103019.pdfDescription of 103019.pdf : Bibliograph
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