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The Brake Pull phenomena is the directional deviation when a strong deceleration is applied, this happens due to asymmetries in the vehicle with diverse origins: dimensional, stiffness, damping, friction and loading condition. This phenomenon creates the necessity of driver inputs on the steering wheel adjusting the vehicle direction to keep the straight line. Great part of asymmetries in the vehicle is avoidable due to building quality, correct maintenance, and others. However, an unequal loading condition on the transversal direction of the vehicle is very common: the vehicle occupied only by the driver is a usual condition. This circumstance creates a load asymmetry that can induces the brake pull phenomena. This study aims to create and validate a virtual toll capable of representing the brake pull phenomena caused by a loading asymmetry.

The objective of this work is to capture the final deformed shape of a vehicle after a rollover caused by a corkscrew event (ramp). With this study, it will be possible to understand the vehicle structural behavior during this event and be able to improve the vehicle safety in this specific condition. For this proposal, it will be presented a virtual methodology using available commercial CAE tools and perform a crashworthiness analysis of the desired event. The first step is to capture the dynamic event through a Multibody analysis that represents the interaction among the vehicle tire, suspension components (Springs, Dampers, Jounce Bumper, Bushings, Stabilizer Bar etc.), vehicle structural stiffness, mass, center of gravity and inertias when exposed to a corkscrew standard ramp, that initiates the rollover event. This methodology will represent with fidelity all dynamic aspects of rollover event before the vehicle touches the ground.

The mass monitoring of assembled vehicles is mandatory to understand if the current production vehicles is in accordance with the already certificated mass and in agreement with Inovar-Auto, Rota 2030 requirements and support vehicle development special the chassis components sizing and vehicle dynamics performance. It is important to highlight that a great part of that measurements happens on the field in a not ideal condition. However, must be a natural deviation of the measured masses due to environmental influences, as the height differences between scale pads for each vehicle corner. Once that a height difference must be impact the vehicle measured mass distribution it is necessary to understand these influences on the measurements results.

The intermediate bracket between the parking brake lever and the conduit receives a reaction force due to the cable friction with the cable. The determination of this force by physical directly measurement is very complicated, due to the system small dimensions making it not compatible with the conventional force transducer, that is not enough space between the reaction bracket and lever base to install the instrumentation. To measure it is necessary a vehicle prototype with sophisticated indirect ways to measure it, as strain gages on the surrounding parts or an intervention in parking brake cable that can affect the final numbers. In addition to measure it by a virtual method is not an easy too.

During a vehicle development, several chassis components suffer tunings, changing its specification as stiffness, damping, preload, etc to attend Handling, Ride and NVH requirements. In other hand, it can change the loads environment and consequently the fatigue life of the components. The objective of this study is to understand the impact in the vehicles loads that can be caused by a suspension tuning, measuring the sensibility of each component tuning. The possible differences of its behavior, in terms of pseudo damage, will be calculated trough Rainflow technique from an original signal obtained with the usage of virtual road loads data acquisition. For that will be considered all possible required specifications of chassis components since the beginning of the project until the end.

The hub driven motors are some of the simpler versions of powertrain to implement an electric motor in a vehicle, hybrid or pure electric. The mechanical simplicity of this concept sounds good for mass reduction, energy efficiency and costs. Also, the split through the road hybrid vehicle concept is very promisor. The opportunity to combine these two concepts is a good chance to develop a simpler hybrid vehicle. However, this concept increases the unsprung mass of the vehicle. The increased mass can deteriorate the cars ride and handling. The objective of this work is to measure the impact of addiction of unsprung mass due to this motor concept in rear axle and evaluate some opportunities to reduce these impacts, with the help of a numerical half car vehicle model and the DOE technique.

The multibody computational simulation is a typically toll used to verify the vehicle dynamic behavior. In this environment, the shock absorber damping curve can be described with a curve considering the force and the speed that are acting on the shock absorber F=f(v) or making this curve as function of force, speed and displacement F=f(v,d). However in the real world the damping curves (F=f(v)), changes during the shock absorber travel. In this case, it is natural to include the displacement variable in the damping modeling making the shock absorber force a function of speed and displacement F=f(v,d). This study will compare how the consideration of each type of curve will affects the simulation results and what kind of dynamic event is relevant to adopt one of the studied shock absorber modeling types.