Search Results

The drivability plays an important role for marketability and competitiveness of passenger car in meeting some customer requirements, which directly affects the driving experience and the desire of purchasing. In this paper, a framework of objective drivability evaluation with multi-source information fusion for passenger car is proposed. At first, according to vehicle powertrain system and optimization theory, certain vehicle performances, which are closely related to objective drivability are analyzed, including vehicle longitudinal acceleration, vehicle speed, engine torque, engine speed, gear position, accelerator pedal, brake signal and voltage signal. Then, combined with the evaluation criterion of signal-to-noise ratio (SNR), mean error (ME), root mean squared error (RMSE) and signal smoothness (SS), a de-noising method is developed for the drivability evaluation information.

Analogous to a vacuum boosted system, Electro-Hydraulic Braking System (EHB) is free from engine vacuum and supplies a braking force proportional to driver input. The independence of engine vacuum makes it especially suitable to be used in electric vehicles (EVs) and hybrid electric vehicles (HEVs). As a key component of EHB, master cylinder is driven by the pump rather than the vacuum booster. Even if the pump fails, the cylinder can also build proper pressure. Meanwhile, in order to maintain the pedal feeling, a pedal stroke simulator is applied in the system. In this paper, aiming at decreasing the size and cost of master cylinder and providing an ideal pedal feeling without compromise of performance, a new integrated master cylinder of EHB system is designed including two parts: master cylinder and pedal stroke simulator. The key components of the integrated master cylinder are motor pump, solenoid valves and composite springs.