Takeshi Inaba

Modelling of magnetorheological semi-active suspension system controlled by semi-active damping force estimator

This paper presents the simulation study of magnetorheological semi-active suspension system controlled by a new proposed algorithm. The control algorithm named as Semi-Active Damping Force Estimator (SADE) is proposed to control the operations of the magnetorheological damper. The simulation of semi-active suspension system was done by considering actual dynamics behaviour of a custom-made magnetorheological damper, where its characteristic testing and modelling are described. The performance of magnetorheological semi-active car suspension system controlled by SADE in term of ride comfort is evaluated in comparison with normal suspension system. The performance of SADE semi-active suspension system is also compared with the skyhook-controlled semi-active suspension system performance. It is shown that magnetorheological semi-active suspension system controlled by SADE is able to improve vehicles ride comfort significantly compared to passive suspension system. The SADE-controlled semi-active suspension system performs more or less the same as skyhook-controlled semi-active suspension system.

Active suspension system in improving ride and handling performance of electric vehicle conversion

This paper presents an evaluation on passenger vehicles ride and handling performance when converted into an electric vehicle (EV). The evaluations were done using a validated 14 degrees of freedom ride and handling model. The mathematical modelling of vehicles ride and handling model as well as its validations are described. Two types of experiments were performed to validate the developed simulation model; the ride test and the handling test. The validated simulation model was used to evaluate the vehicles ride and handling performance of the vehicle when converted into an electric vehicle. The evaluation involves two weight distribution ratios which are 60:40, for normal vehicle and 40:60 for EV conversion. The validated simulation model used active suspension system in order to improve the EV conversions ride and handling performance. It is found that modification into EV affects vehicles handling performance quite significant but not ride performance. The EV conversions weight, which is distributed towards the rear of the vehicle, causes the vehicle to travel off from its original travelling path. The application of active suspension system is proposed to improve EV conversions handling performance as well as its ride comfort performance.

Fuzzy semi-active damping force estimator (fSADE) and skyhook semi-active suspension systems

This paper presents the comparative study on semi-active suspension controlled by skyhook algorithm and fuzzy semi-active damping force estimator (fSADE). The damping element used in the semi-active suspension is non-pressurised magnetorheological (MR) damper. The performance of magnetorheological semi-active suspension system controlled by fSADE in terms of ride comfort is evaluated in comparison with normal suspension system and skyhook semi-active suspension system. The study is also focusing on the effects of the number of fuzzy rules used in fSADE algorithm performance. Other aspects studied are the current consumption used by the MR damper as well as the damper’s ability to execute the damping forces as estimated by the controllers. The vehicle ride comforts are evaluated based on the vehicle’s vertical motions (jerk, acceleration, displacement) and pitch motions (pitch rate and pitch angle). It is shown that magnetorheological semi-active suspension system controlled by fSADE is able to improve veh...

Improving Electric Vehicle Conversion’s Ride and Handling Performance Using Active Suspension System

This paper present an evaluation on passenger vehicle’s ride and handling performance if being converted into an electric vehicle. The mathematical modelling of vehicle’s ride and handling model as well as its validations are described. The simulation model was used to evaluate the vehicle’s ride and handling performance when converted into an electric vehicle. The validated simulation model was also integrated with an active suspension system in order to improve the EV conversion’s ride and handling performance. It was found that the modifications towards an EV conversion only affect the vehicle’s handling performance significantly. The modifications which change the weight distribution, which biased to the rear of the vehicle, will cause the vehicle to travel off from its original traveling path. The application of active suspension is possibly being used in correcting this condition as well as further improving the EV conversion’s ride comfort performance.