Recent development in computer-based manufacturing and inspection has necessitated extended knowledge and usage of geometric tolerances as carriers of design intent. The aim of applying geometrical tolerances in desig...Recent development in computer-based manufacturing and inspection has necessitated extended knowledge and usage of geometric tolerances as carriers of design intent. The aim of applying geometrical tolerances in design is to provide function-oriented precise description of part geometry where the conventional size tolerance system fails to address. In view of the current development of computer-aided systems, applying geometric tolerances opens a new research front. This article examines the challenges in applying geometric tolerance information to carry the design intent to other downstream manufacturing processes and intelligently integrate the whole system. Based on the observed practical capabilities and literature studies, it is concluded that the current computer-aided design （CAD） systems cannot effectively provide the appropriate use of geometric tolerances. This article highlights the existing challenges and proposes a scheme of algorithm development for appropriate use of tolerance symbols and conditions at the design specification stage. This, in the long run, enables the CAD model to carry the design intent and opens a window of opportunity for intelligently integrating manufacturing systems.展开更多
Brake drag is the main factor affecting the transmission efficiency and vehicle fuel consumption. This paper focused on analyzing the impact of assembled disc lateral runout on brake drag. First the impact mechanism o...Brake drag is the main factor affecting the transmission efficiency and vehicle fuel consumption. This paper focused on analyzing the impact of assembled disc lateral runout on brake drag. First the impact mechanism of lateral disc runout on drag was analyzed theoretically. Then the brake drag torque under different assembled disc lateral runout was tested to figure out the relationship between them. And then, the influence factors on disc lateral runout were analyzed and the disc lateral runout was optimized. Finally, the vehicle resistance of the original car and the prototype with optimized brake were compared. The result shows that the vehicle resistance after optimized is reduced by 3%.展开更多
文摘Recent development in computer-based manufacturing and inspection has necessitated extended knowledge and usage of geometric tolerances as carriers of design intent. The aim of applying geometrical tolerances in design is to provide function-oriented precise description of part geometry where the conventional size tolerance system fails to address. In view of the current development of computer-aided systems, applying geometric tolerances opens a new research front. This article examines the challenges in applying geometric tolerance information to carry the design intent to other downstream manufacturing processes and intelligently integrate the whole system. Based on the observed practical capabilities and literature studies, it is concluded that the current computer-aided design （CAD） systems cannot effectively provide the appropriate use of geometric tolerances. This article highlights the existing challenges and proposes a scheme of algorithm development for appropriate use of tolerance symbols and conditions at the design specification stage. This, in the long run, enables the CAD model to carry the design intent and opens a window of opportunity for intelligently integrating manufacturing systems.
文摘Brake drag is the main factor affecting the transmission efficiency and vehicle fuel consumption. This paper focused on analyzing the impact of assembled disc lateral runout on brake drag. First the impact mechanism of lateral disc runout on drag was analyzed theoretically. Then the brake drag torque under different assembled disc lateral runout was tested to figure out the relationship between them. And then, the influence factors on disc lateral runout were analyzed and the disc lateral runout was optimized. Finally, the vehicle resistance of the original car and the prototype with optimized brake were compared. The result shows that the vehicle resistance after optimized is reduced by 3%.
