Juan Dols

An Active Safety System for Low-Speed Bus Braking Assistance

Accidents in which buses or coaches are involved cause thousands of injuries and fatalities every year. To reduce their number and severity, this paper describes an advanced driver assistance system (ADAS) based on a haptic throttle pedal and emergency braking. It also proposes a computationally efficient algorithm with a methodology based on three main concepts: a simplified but accurate vehicle model, an efficient collision detection system considering the drivers intention and pedestrians wandering around the vehicle, and a risk evaluation system to generate warnings and emergency braking signals. Finally, the performance of the proposed ADAS is validated using a driving simulation cabin with a very realistic urban scenario and original elements from real buses. The results show a statistically significant improvement in safety, as the number of collisions and high-risk situations are clearly minimized, the reaction time to press the brake pedal is improved, and the time to collision increased in emergency situations. Implementation of the proposed ADAS into city buses would potentially improve safety, reducing the frequency and severity of accidents in pedestrians.

Validation of a Low-Cost Driving Simulator Based on Continuous Speed Profiles

The number of road safety studies that are based on driving simulators is growing significantly. The Polytechnic University of Valencia, Spain, developed a low-cost driving simulator for the assessment, training, and rehabilitation of drivers (SE2RCO). The main objective of this research was the validation of the driving simulator so that studies about road safety and highway geometric design that considered human factors could be performed. The validation was based on continuous speed profiles collected from 28 volunteers on a 30-km-long, two-lane rural road section. The same volunteers drove through the same road section built in SE2RCO. Speed data of 79 curves and 52 tangents were selected for the analysis. Comparison of the real and simulated speeds ensured the simulator’s objective validity according to average and operating speeds. Two models were developed to predict field speeds from simulated speeds. Results showed that a simulated average speed lower than approximately 90 km/h was linked to a similar real average speed. For higher simulated speeds, the average speed in the real environment was lower than the simulated one. In addition, the actual operating speed was around 5 km/h lower than the operating speed in the driving simulator. Most volunteers assessed the quality and similarity of the virtual environment compared with the real world as medium or high and assessed the driving tasks similarly, thus achieving subjective validation of the simulator.

Transportation Safety Requirements in the Use of Pushchairs on Buses

The safe use of buses by passengers travelling with pushchairs for young children is a mobility problem that has not yet been satisfactorily resolved. The lack of national and international standards in this area in the past led to the development of a research project developed jointly by the Universitat Politècnica València and the Universidad Politècnica Madrid (Spain). This paper shows a comparative study to evaluate the dynamic behaviour in case of low-g accidents reproducing frontal impacts resembling real traffic events (deceleration 2g, ΔV 20 km/h) of a new pushchair restraint system against the use of back-restraint by pushchairs as establishes R 10706 series of amendments. In the dynamic trials, three pushchair restraint prototypes and a typical wheelchair back-restraint system combined with two worst-case up-to-date pushchair models in misuse and correct use configurations were tested. The results demonstrated the need for preventing children injuries as a consequence of low-g accidents. The new design meets and improves the latest revision of regulation R107 regarding the use of restraint systems for the transport of wheelchair and pushchair passengers and represents an advance for pushchairs travelling on buses.

Diseño de actividades y uso de la coevaluación para fomentar el desarrollo de competencias transversales en ingeniería mecánica y de materiales

En esta comunicacion se presentan las actividades de evaluacion desarrolladas en el marco de un Proyecto de Innovacion y Mejora Educativa, junto con algunos resultados preliminares. El principal objetivo de este proyecto es el diseno de actividades de evaluacion que fuercen a los estudiantes a desarrollar sus competencias transversales, al mismo tiempo que permitan a los profesores evaluar su desempeno en las competencias cientifico-tecnicas. Se emplea un enfoque de evaluacion formativa, de forma que las actividades de evaluacion sean utiles a los estudiantes para mejorar su aprendizaje. Palabras clave: competencias transversales, actividades de evaluacion, coevaluacion

Validación de un simulador de conducción de bajo coste para el diseño de carreteras convencionales

La cantidad de estudios de seguridad vial basados en simuladores de conduccion esta en continuo crecimiento. En este sentido, la Universitat Politecnica de Valencia (UPV) ha desarrollado un simulador de conduccion de bajo coste: SE 2 RCO (Simulador para la Evaluacion, Entrenamiento y Rehabilitacion de Conductores). El principal objetivo de la investigacion es la validacion de este simulador, con el fin de desarrollar estudios relacionados con la seguridad vial y el diseno geometrico de carreteras incorporando el factor humano. Dicha validacion se ha realizado a partir de la observacion en campo de los perfiles continuos de velocidad desarrollados por 28 voluntarios conduciendo su propio vehiculo en un tramo de carretera convencional de 30 km. Los mismos voluntarios condujeron posteriormente en el simulador de conduccion ese mismo tramo de carretera reconstruido en un entorno virtual. Un total de 79 curvas y 52 rectas fueron objeto de analisis. La comparacion entre las velocidades desarrolladas en la realidad y las observadas durante la simulacion permitieron llevar a cabo la validez objetiva del simulador de conduccion. Los resultados mostraron que la velocidad media en el simulador y en la realidad era similar cuando la velocidad simulada era inferior a 87.3 km/h. En caso de ser superior, la velocidad media en la realidad era menor que en el simulador. En cuanto a la velocidad de operacion, se observo que la velocidad real era aproximadamente 5 km/h menor que la simulada. Finalmente, estos resultados estuvieron apoyados por la percepcion de los conductores, ya que la mayoria de ellos evaluaron la calidad del entorno simulado y el grado de similitud entre la tarea de conduccion real y simulada como medio o alto, consiguiendo de esta manera la validez subjetiva del simulador de conduccion. DOI: http://dx.doi.org/10.4995/CIT2016.2016.3444

Haptic Feedback to Assist Bus Drivers for Pedestrian Safety at Low Speed

Buses and coaches are massive Passenger Transportation Systems (PTS), because they represent more than half of land PTS in the European Union. Despite that, bus accident figures are lower than other means of transport, but its size and weight increase the severity of accidents in which buses are involved, even at low speed. In urban scenarios, turnings and maneuvers around bus stops are the main causes of accidents, mostly due to low visibility, blind spots, or drivers distractions. Therefore, there is an increasing interest in developing driving assistance systems to avoid these situations, among others. However, even though there are some solutions on the market, they are not meant to work in urban areas at low speed and with the sole purpose of preventing collisions with pedestrians. In this sense, the paper proposes an active safety system for buses in maneuvers at low speed. The safety system consists of haptic feedback devices together with collision avoidance and risk evaluation systems based on detected people nearby the bus. The performance of the active safety system has been validated in a simulated urban scenario. Our results show that drivers reaction time is reduced and time to collision increased due to the proposed low-speed active safety system. In particular, it is shown that there is a reduction in the number of high risk cases and collisions, which implies a considerable improvement in safety terms. In addition to this, a brief discussion about current regulations for innovative safety systems on real vehicles is carried out.

Good practices and universal accessibility to urban buses of children prams

Present work has been performed with the results achieved in the research project: “DETERMINATION OF THE ACCESIBILITY AND SAFETY REQUIREMENTS OF THE USE OF PRAMS AND PUSHCHAIRS IN PUBLIC TRANSPORT (ASUCAR)”. The specific objectives pretended were: the determination of the accessibility conditions of the children prams, the study and definition of the needs of use of restraint systems for these devices and their occupants, to analyze the strength of the prams structures, as well as, the development of a new restraint system for children prams that could be used in the most universal way in urban buses. The results were implemented in a good practice code that could be the basis for new regulation regarding the transport of children in buses.ResumenLa presente publicación se realiza a partir de los resultados obtenidos en el proyecto de investigación “DETERMINACIÓN DE LOS REQUISITOS DE ACCESIBILIDAD Y SEGURIDAD EN LA UTILIZACIÓN DE CARRITOS DE NIÑOS EN VEHÍCULOS DE TRANSPORTE PÚBLICO” (ASUCAR). Como objetivos particulares se pretendía analizar las condiciones de accesibilidad de los carritos de niños (CdN) en todas sus posibilidades, estudiar y definir las necesidades de utilización de sistemas de retención para los cochecitos y sus ocupantes, analizar la resistencia de los actuales modelos de carritos de niños, así como el desarrollo de un nuevo dispositivo de sistema de retención para los carritos de niños que pudiera utilizarse de la forma más universal en autobuses urbanos de transporte público. Los resultados se han concretado en la definición de un “Código de Buenas Prácticas para el Transporte de Carritos de Niños en Vehículos de Transporte Público”, que podrá servir como base científica para el desarrollo de futuras normativas de seguridad relacionadas con este colectivo.

Buenas prácticas y accesibilidad universal a los autobuses urbanos de carritos de niños

Present work has been performed with the results achieved in the research project: “DETERMINATION OF THE ACCESIBILITY AND SAFETY REQUIREMENTS OF THE USE OF PRAMS AND PUSHCHAIRS IN PUBLIC TRANSPORT (ASUCAR)”. The specific objectives pretended were: the determination of the accessibility conditions of the children prams, the study and definition of the needs of use of restraint systems for these devices and their occupants, to analyze the strength of the prams structures, as well as, the development of a new restraint system for children prams that could be used in the most universal way in urban buses. The results were implemented in a good practice code that could be the basis for new regulation regarding the transport of children in buses.ResumenLa presente publicación se realiza a partir de los resultados obtenidos en el proyecto de investigación “DETERMINACIÓN DE LOS REQUISITOS DE ACCESIBILIDAD Y SEGURIDAD EN LA UTILIZACIÓN DE CARRITOS DE NIÑOS EN VEHÍCULOS DE TRANSPORTE PÚBLICO” (ASUCAR). Como objetivos particulares se pretendía analizar las condiciones de accesibilidad de los carritos de niños (CdN) en todas sus posibilidades, estudiar y definir las necesidades de utilización de sistemas de retención para los cochecitos y sus ocupantes, analizar la resistencia de los actuales modelos de carritos de niños, así como el desarrollo de un nuevo dispositivo de sistema de retención para los carritos de niños que pudiera utilizarse de la forma más universal en autobuses urbanos de transporte público. Los resultados se han concretado en la definición de un “Código de Buenas Prácticas para el Transporte de Carritos de Niños en Vehículos de Transporte Público”, que podrá servir como base científica para el desarrollo de futuras normativas de seguridad relacionadas con este colectivo.