Castillo Aguilar J.J.,Doctor Ortiz Ramos s n |
Cabrera Carrillo J.A.,Doctor Ortiz Ramos s n |
Guerra Fernandez A.J.,Doctor Ortiz Ramos s n |
Postigo Pozo S.,Doctor Ortiz Ramos s n
Sensors (Switzerland) | Year: 2017
Tire characteristics and behavior are of great importance in vehicle dynamics since the forces transmitted in the tire-road contact are the main contributors to global vehicle performance. Several research groups have focused on the study and modeling of tires. Some of the most important factors that need to be known are tread characteristics and pressure distribution in the tire-ground contact patch. In this work, a test bench has been used to adequately determine the aforementioned factors. The measurement principle of the test bench is the frustration of total internal reflection (FTIR) of light. It makes use of a laterally illuminated glass on which the tire leans. An interposed plastic interface between them causes the reflection of light. Finally, a video camera captures the bright image formed through the glass. The brightness level in each pixel of the image is related to existing normal pressure. A study of the parameters that affect the test bench calibration such as type of interface material used, diffuse light, hysteresis, creep and transverse light absorption is performed. Experimental tests are conducted to relate tire inflation pressure and camber angle to the pressure distribution. Furthermore, the test bench is used to detect and evaluate the influence of defects in the tire on the contact pressures. © 2017 by the authors. Licensee MDPI, Basel, Switzerland.
Aguilar J.J.C.,Doctor Ortiz Ramos s n |
Carrillo J.A.C.,Doctor Ortiz Ramos s n |
Fernandez A.J.G.,Doctor Ortiz Ramos s n |
Acosta E.C.,Doctor Ortiz Ramos s n
Sensors (Switzerland) | Year: 2015
The appearance of active safety systems, such as Anti-lock Braking System, Traction Control System, Stability Control System, etc., represents a major evolution in road safety. In the automotive sector, the term vehicle active safety systems refers to those whose goal is to help avoid a crash or to reduce the risk of having an accident. These systems safeguard us, being in continuous evolution and incorporating new capabilities continuously. In order for these systems and vehicles to work adequately, they need to know some fundamental information: the road condition on which the vehicle is circulating. This early road detection is intended to allow vehicle control systems to act faster and more suitably, thus obtaining a substantial advantage. In this work, we try to detect the road condition the vehicle is being driven on, using the standard sensors installed in commercial vehicles. Vehicle models were programmed in on-board systems to perform real-time estimations of the forces of contact between the wheel and road and the speed of the vehicle. Subsequently, a fuzzy logic block is used to obtain an index representing the road condition. Finally, an artificial neural network was used to provide the optimal slip for each surface. Simulations and experiments verified the proposed method. © 2015 by the authors; licensee MDPI, Basel, Switzerland.