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The particulate emissions of two brake systems were characterized in a dilution tunnel optimized for PM10 measurements. The larger of them employed a fixed caliper (FXC) and the smaller one a floating caliper (FLC). Both used ECE brake pads of the same lining formulation. Measured properties included gravimetric PM2.5 and PM10, Particle Number (PN) concentrations of both untreated and thermally treated (according to exhaust PN regulation) particles using Condensation Particle Counters (CPCs) having 23 and 10 nm cut-off sizes, and an Optical Particle Sizer (OPS). The brakes were tested over a section (trip-10) novel test cycle developed from the database of the Worldwide harmonized Light-Duty vehicles Test Procedure (WLTP). A series of trip-10 tests were performed starting from unconditioned pads, to characterize the evolution of emissions until their stabilization. Selected tests were also performed over a short version of the Los Angeles City Cycle.

The structural design of current vehicle front units has to account for an increasing number of constraints: improvement of real-world performance in safety for occupants and others road users, perform in the various ratings and meet future regulations. Therefore the structural car design is the result of a compromise between pedestrian protection, car-to-car compatibility and self- protection. In addition to these safety considerations, reparability constraints are becoming more and more demanding and intrusive toward the other safety requirements. The need to reduce emissions through fuel consumption control requires a reduction of the overall body weight which leads usually to more difficulties to achieve a correct structural behavior. Some of these constraints lead to solutions which are in opposition and in general to unsatisfactory compromises. It is suggested to develop a more comprehensive approach in order to better take into account both safety requirements and reparability.

The measurement of the particle number (PN) concentration of non-volatile particles ≻23 nm was introduced in the light-duty vehicles regulation; the heavy-duty regulation followed. Based on the findings of the Particle Measurement Program (PMP), heavy-duty inter-laboratory exercise, the PN concentration measurement can be conducted either from the full dilution tunnel with constant volume sampling (CVS) or from the partial flow dilution system (PFDS). However, there are no other studies that investigate whether the PN results from the two systems are equivalent. In addition, even the PMP study never investigated the uncertainty that is introduced at the final result from the extraction of a flow by a PN system from the PFDS. In this work we investigate the uncertainty for the three possible cases, i.e., considering a constant extracted flow from the PFDS, sending a signal with 1 Hz frequency to the PFDS, or feeding back the extracted flow to the PFDS.

Real world operating scenarios have a major influence on emissions and fuel consumption. To reduce climate-relevant and environmentally harmful gaseous emissions and the exploitation of fossil resources, deep understanding concerning the real drive behavior of mobile sources is needed because emissions and fuel consumption of e.g. passenger cars, operated in real world conditions, considerably differ from the officially published values which are valid for specific test cycles only [1]. Due to legislative regulations by the European Commission a methodology to measure real drive emissions RDE is well approved for heavy duty vehicles and automotive applications but may not be adapted similar to two-wheeler-applications. This is due to several issues when using the state of the art portable emission measurement system PEMS that will be discussed.

Accident studies show that incompatibility has become the main cause of fatal injury in car-to-car accidents. There is a general agreement today that improving compatibility is one of the most effective ways to reduce the number of road accident victims. Therefore, structural car design must take into account other road users without decreasing self-protection level supplied by all new passenger cars. In addition to these safety considerations, the front unit structural design has to account for an increasing number of constraints: improvement of real-world performance in safety, fulfill current and future regulations like "CAFÉ" or pedestrian, reducing utilization costs and so on. Furthermore, European fleet is changing in mass and in size, as the world's ones, and new fashion vehicles appear different than the previous one.

After a lot of researches in the field of compatibility through testing and accident analysis, the current knowledge allows us to propose a new test protocol able to control the two issues of compatibility: partner and self protection. In other words, the procedure would be able to assess the most relevant parameters: structural interaction (geometry / stiffness) and compartment strength (stiffness). The most effective way to meet this target is to control both of them at the same time, thus avoiding many test regulations. The new final protocol will be a mix of two very well known test configurations: current frontal regulation in Europe (ECE 94) to assess compartment strength and structural integrity through vehicle and dummy criteria Progressive Deformable Barrier test (PDB) to assess and control force distribution through barrier deformation.