Abrasives,such as oxides of alumina(Al),silica(Si),zirconia(Zr),chromium(Cr)etc.,are added to raise the friction level and also to remove the glaze on the disc so that surface will be rejuvenated continuously during b...Abrasives,such as oxides of alumina(Al),silica(Si),zirconia(Zr),chromium(Cr)etc.,are added to raise the friction level and also to remove the glaze on the disc so that surface will be rejuvenated continuously during braking and will contribute to maintain the desired friction level.However,these inorganic particles have less adhesion with the resin/binder and hence are easily dug out during wearing process contributing to higher wear.If efforts are made to enhance the filler‐matrix adhesion,not only the wear of friction material(FM)should reduce,the particles may stay for a longer time on the tribo‐surface of the pads to contribute fully towards controlling the coefficient of friction(μ).In the present study,alumina particles were selected for siloxane treatment to improve the filler‐matrix adhesion.Two types of eco‐friendly(free from asbestos and Cu)brake‐pads were developed using alumina as a theme ingredient(treated and untreated)keeping all the parent formulation identical.An additional type of brake‐pads without alumina particles was also developed to observe the effect of abrasive particles on the tribo‐performance.The performance properties(physical,mechanical,and tribological)of brake‐pads were compared when evaluated in identical conditions.The tribotesting was done on full‐scale brake inertia dynamometer following the procedure in Japanese automobile standard(JASO C 406).It was observed that siloxane treatment affected both friction and wear of brake‐pads in a beneficial way.Wear resistance got increased 35%for siloxane treated pads.Worn surfaces were analysed using scanning electron microscopy(SEM)and energy dispersive X‐ray(EDAX)technique.展开更多
The suspension system is a key element in motor vehicles. Advancements in electronics and microprocessor technology have led to the realization of mechatronic suspensions. Since its introduction in some production mot...The suspension system is a key element in motor vehicles. Advancements in electronics and microprocessor technology have led to the realization of mechatronic suspensions. Since its introduction in some production motorcars in the 1980 s, it has remained an area which sees active research and development, and this will likely continue for many years to come. With the aim of identifying current trends and future focus areas, this paper presents a review on the state-of-the-art of mechatronic suspensions. First, some commonly used classifications of mechatronic suspensions are presented. This is followed by a discussion on some of the actuating mechanisms used to provide control action. A survey is then reported on the many types of control approaches, including look-ahead preview, predictive, fuzzy logic, proportional–integral–derivative(PID), optimal, robust, adaptive, robust adaptive,and switching control. In conclusion, hydraulic actuators are most commonly used, but they impose high power requirements, limiting practical realizations of active suspensions. Electromagnetic actuators are seen to hold the promise of lower power requirements, and rigorous research and development should be conducted to make them commercially usable. Current focus on control methods that are robust to suspension parameter variations also seems to produce limited performance improvements, and future control approaches should be adaptive to the changeable driving conditions.展开更多
文摘Abrasives,such as oxides of alumina(Al),silica(Si),zirconia(Zr),chromium(Cr)etc.,are added to raise the friction level and also to remove the glaze on the disc so that surface will be rejuvenated continuously during braking and will contribute to maintain the desired friction level.However,these inorganic particles have less adhesion with the resin/binder and hence are easily dug out during wearing process contributing to higher wear.If efforts are made to enhance the filler‐matrix adhesion,not only the wear of friction material(FM)should reduce,the particles may stay for a longer time on the tribo‐surface of the pads to contribute fully towards controlling the coefficient of friction(μ).In the present study,alumina particles were selected for siloxane treatment to improve the filler‐matrix adhesion.Two types of eco‐friendly(free from asbestos and Cu)brake‐pads were developed using alumina as a theme ingredient(treated and untreated)keeping all the parent formulation identical.An additional type of brake‐pads without alumina particles was also developed to observe the effect of abrasive particles on the tribo‐performance.The performance properties(physical,mechanical,and tribological)of brake‐pads were compared when evaluated in identical conditions.The tribotesting was done on full‐scale brake inertia dynamometer following the procedure in Japanese automobile standard(JASO C 406).It was observed that siloxane treatment affected both friction and wear of brake‐pads in a beneficial way.Wear resistance got increased 35%for siloxane treated pads.Worn surfaces were analysed using scanning electron microscopy(SEM)and energy dispersive X‐ray(EDAX)technique.
基金Project supported by the Ministry of Education,Malaysia(No.ERGS/1/2012/TK01/UKM/02/4)
文摘The suspension system is a key element in motor vehicles. Advancements in electronics and microprocessor technology have led to the realization of mechatronic suspensions. Since its introduction in some production motorcars in the 1980 s, it has remained an area which sees active research and development, and this will likely continue for many years to come. With the aim of identifying current trends and future focus areas, this paper presents a review on the state-of-the-art of mechatronic suspensions. First, some commonly used classifications of mechatronic suspensions are presented. This is followed by a discussion on some of the actuating mechanisms used to provide control action. A survey is then reported on the many types of control approaches, including look-ahead preview, predictive, fuzzy logic, proportional–integral–derivative(PID), optimal, robust, adaptive, robust adaptive,and switching control. In conclusion, hydraulic actuators are most commonly used, but they impose high power requirements, limiting practical realizations of active suspensions. Electromagnetic actuators are seen to hold the promise of lower power requirements, and rigorous research and development should be conducted to make them commercially usable. Current focus on control methods that are robust to suspension parameter variations also seems to produce limited performance improvements, and future control approaches should be adaptive to the changeable driving conditions.
