Optimal emergency vehicle braking control based on dynamic friction model

 

L. Olmos & L. Álvarez-lcaza

 

Instituto de Ingeniería, Universidad Nacional Autónoma de México. 04510, Coyoacán DF, México. LOlmosG@iingen.unam.mx alvar@pumas.iingen.unam.mx

 

Received: January 20^th 2003.
Accepted: March 30^th 2005.

 

Abstract

A dynamic friction model for the tire-road interface is used in an optimal control scheme for emergency braking of vehicles. The controller sets a target relative velocity curve that the vehicle must track in order to achieve braking in minimum time. It is shown that this curve corresponds to the solution of a minimum time optimal control problem. The final goal of the control is to improve the safety levels in highway transportation.

Keywords: Optimal control, Vehicular control, Dynamic friction model.

 

Resumen

Se utiliza un modelo dinámico de fricción para la interfase llanta-pavimento en el diseño de un esquema de control óptimo para el frenado de emergencia de vehículos. El controlador establece una curva de referencia para la velocidad relativa que el vehículo debe seguir para poder alcanzar el frenado en tiempo mínimo. Se muestra que esta curva corresponde con la solución de un problema de control óptimo. El objetivo final de este esquema de control es aumentar los niveles de seguridad en autopistas.

 

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Acknowledgments

Research partially financed by CONACYT grant 31226U.

 

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