Over the years, automobile market has experience significant growth due to increasing demand for more sophisticated luxurious vehicles that can give better comfortable ride. In order to improve the comfort experienced by... more
Over the years, automobile market has experience significant growth due to increasing demand for more sophisticated luxurious vehicles that can give better comfortable ride. In order to improve the comfort experienced by the occupants of a vehicle, accurate modeling of an active suspension system with an intelligent control algorithm is paramount. In this paper,an overview of the vehicle suspension system was presented. The different classifications of the suspension system were discussed. The State Space approach was used to develop the mathematical model of an Active Suspension System from its block diagram representation.
The purpose of this paper is to determine the lumped suspension parameters that minimise a multiobjective function in a vehicle model under different standard PSD road profiles. This optimisation tries to meet the rms vertical... more
The purpose of this paper is to determine the lumped suspension parameters that minimise a multiobjective function in a vehicle model under different standard PSD road profiles. This optimisation tries to meet the rms vertical acceleration weighted limits for human sensitivity curves from ISO 2631 [ISO-2631: guide for evaluation of human exposure to whole-body vibration. Europe; 1997] at the driver’s seat, the road holding capability and the suspension working space. The vehicle is modelled in the frequency domain using eight degrees of freedom under a random road profile. The particle swarm optimisation and sequential quadratic programming algorithms are used to obtain the suspension optimal parameters in different road profile and vehicle velocity conditions. A sensitivity analysis is performed using the obtained results and, in Class G road profile, the seat damping has the major influence on the minimisation of the multi-objective function. The influence of vehicle parameters in vibration attenuation is analysed and it is concluded that the front suspension stiffness should be less stiff than the rear ones when the driver’s seat relative position is located forward the centre of gravity of the car body. Graphs and tables for the behaviour of suspension parameters related to road classes, used algorithms and velocities are presented to illustrate the results. In Class A road profile it was possible to find optimal parameters within the boundaries of the design variables that resulted in acceptable values for the comfort, road holding and suspension working space.
Driving cycle is commonly known as the relationship and a series of speedtime profile. The study on this discipline aids vehicle manufacturers in vehicle construction, environmentalists in studying environment quality in proportion with... more
Driving cycle is commonly known as the relationship and a series of speedtime profile. The study on this discipline aids vehicle manufacturers in vehicle construction, environmentalists in studying environment quality in proportion with vehicle emissions and traffic engineers to further investigate the behaviour of drivers and the road conditions which assist automotive industry in a better and energy efficient vehicle productions. In order to develop a proper driving cycle for selected routes, information and data based on real-time driving behaviour is important. This research focusses on the modelling of each component and latter designing a conceptual model in Simulink which takes up the data of speed of vehicles in SI unit which is m/s and draws out distance travelled and acceleration of the vehicle together with driving cycle of the route for given timestamp. This relation will be verified with existing Kuala Terengganu BasKITe driving cycle, highway fuel economy test (HWFET), new europian driving cycle (NEDC) and worldwide harmonised light vehicle test procedure (WLTP) driving cycles for the use of future projects and improvements of technology in studies and analysis of powertrain and electric vehicle performances.
