Design, Simulation und Erprobung einer aktiven Sitzaufhängung für Nutzfahrzeuge

Nutzfahrzeuge müssen oft durch sehr unebenes Gelände gefahren werden. In diesem Fall wird der Fahrer starken Vibrationen ausgesetzt, die von der Fahrzeugkarosserie durch die Sitzaufhängung auf ihn wirken. Um diese Schwingungen zu verringern, werden die Sitzaufhängungen in der Regel mit Feder-Dämpfer-Systemen ausgerüstet. Jedoch erreichen die passiven Systeme vor allem bei niederfrequenten Schwingungen ihre physikalischen Grenzen. Eine wesentliche Verbesserung des Sitzkomforts kann unter solchen Anregungsbedingungen nur mit einer aktiven Sitzaufhängung erreicht werden. In diesem Beitrag wird ein neuartiges aktives System für die Sitzaufhängung auf Basis von elektrorheologischen Flüssigkeiten vorgestellt. Außerdem werden die theoretischen Grundlagen für die Modellierung der beschriebenen aktiven Sitzaufhängung dargestellt. Anschließend werden die Simulationsergebnisse mit den Messergebnissen unter realen Betriebsbedingungen verglichen. Die Repräsentation der Ergebnisse mit Hilfe der im Bereich der Sitztechnik weit verbreiteten SEAT-Werten (Seat Effective Amplitude Transmissibility) zeigt das Potenzial des entwickelten Systems zur aktiven Reduktion der Schwingungsbelastung des Fahrers und ermöglicht seine objektive Bewertung.

Comparing fuzzy and intelligent PI controllers in stop-and-go manoeuvres

The aim of this work was twofold: on the one hand, to describe a comparative study of two intelligent control techniques-fuzzy and intelligent proportional-integral (PI) control, and on the other, to try to provide an answer to an as yet unsolved topic in the automotive sector-stop-and-go control in urban environments at very low speeds. Commercial vehicles exhibit nonlinear behavior and therefore constitute an excellent platform on which to check the controllers. This paper describes the design, tuning, and evaluation of the controllers performing actions on the longitudinal control of a car-the throttle and brake pedals-to accomplish stop-and-go manoeuvres. They are tested in two steps. First, a simulation model is used to design and tune the controllers, and second, these controllers are implemented in the commercial vehicle-which has automatic driving capabilities-to check their behavior. A stop-and-go manoeuvre is implemented with the two control techniques using two cooperating vehicles.

Análise de consistência de traçado de uma rodovia de múltiplas faixas.

O número de acidentes de trânsito é crescente nas últimas décadas no Brasil. Uma das principais causas de acidentes em rodovias brasileiras é o excesso de velocidade, que contribui para a possibilidade de ocorrência de acidentes. As velocidades praticadas pelos motoristas são também função dos elementos geométricos que compõem a via (raio, rampa, largura da faixa, etc). A consistência de traçado não afeta a expectativa dos motoristas e garante uma operação segura. A maioria dos motoristas consegue perceber as falhas de coordenação, mas tecnicamente, por exemplo, desconhecem a origem das mesmas. Esta pesquisa apresenta como objetivo a análise de consistência de um trecho de uma determinada rodovia do país de múltiplas faixas, com elevado índice de acidentes e alto fluxo de veículos comerciais. Os pontos com maior ocorrência de acidentes foram identificados e realizaram-se medições de velocidade para elaboração de um modelo de previsão de velocidade operacional (V85) do trecho de estudo. De posse deste modelo, procedeu-se à análise de consistência através do método dos critérios de segurança, que identificou 2 seções com problemas de consistência. Por fim, verificou-se se estas seções correspondiam aos locais de maior número de acidentes: a tangente T5 precede uma curva com alto índice de acidentes (km 511+000); o local com maior concentração de acidentes (km 514) foi classificado como RAZOÁVEL.

National intelligent transportation infrastructure initiative.

Mode of access: Internet.

Intelligent Transportation Systems: real world benefits.

Transportation Department, Joint Program Office for Intelligent Transportation Systems, Washington, D.C.

The office of motor carriers 5-year research and technology plan.

Mode of access: Internet.

Wyoming CVISN program plan.

Wyoming Highway Patrol, Commercial Carrier Section, Cheyenne

Virtual weigh station.

Indiana Department of Transportation, Indianapolis

Heavy vehicle safety research: a new agenda for the 21st century. Prepared in response to Senate Report 103-310; Senate Appropriations Committee; H.R. 4556; Department of Transportation and Related Agencies Appropriations Bill 1995.

Mode of access: Internet.

Institutional barriers to the deployment of CVO/IVHS innovations in Ohio. Final report.

Ohio Department of Transportation, Columbus

The federal motor carrier safety program: not yet achieving what the congress wanted. Report to the congress.

Mode of access: Internet.

Intelligent transportation systems benefits: 2001 update.

Transportation Department, Joint Program Office for Intelligent Transportation Systems, Washington, D.C.

Executive order no. 2016-18

This executive order by Governor Nikki Haley determines that an emergency exists in the State South Carolina for the limited purpose of complying with the declaration of emergency in the State of North Carolina and accordingly directs the State Transport Police Division of the South Carolina Department of Public Safety as needed to suspend the federal rules and regulations that limit the hours of operation of commercial vehicles providing relief for the emergency declared in the State of North Carolina due to the winter storm.

Executive order no. 2016-21

This executive order by Governor Nikki R. Haley determines that an emergency exists in the State South Carolina for the limited purpose of complying with the declaration of emergency in the State of Georgia and accordingly direct the South Carolina Department of Transportation and the South Carolina Department of Public Safety, and the State Transport Police as needed, to suspend the federal rules and regulations that limit the hours operators of commercial vehicles may drive, in order to ensure the uninterrupted supply of gasoline and other fuels needing to be moved on the highways of Georgia.

Executive order no. 2016-44

This executive order by Governor Nikki R. Haley determines that an emergency exists in the State South Carolina for the limited purpose of complying with the declaration of emergency in the State of Georgia and hereby suspend of Part 395 (drivers' hours of service) of Title 49 of the Code of Federal Regulations. She further directs the South Carolina Department of Transportation and the South Carolina Department of Public Safety, and the State Transport Police as needed, to suspend the federal rules and regulations that limit the hours operators of commercial vehicles may drive, in order to ensure the uninterrupted supply of equipment, goods, services, and any other item needing to be moved on the highways of the States of Georgia and South Carolina.