To improve the accuracy of capacity analysis and prediction for the aircraft assembly stations,an approach for calculating the effective working hour(EWH)of automatic assembly equipment is introduced by using the dyna...To improve the accuracy of capacity analysis and prediction for the aircraft assembly stations,an approach for calculating the effective working hour(EWH)of automatic assembly equipment is introduced by using the dynamic mixed Weibull distribution(DMWD)model.Firstly,according to the features of aircraft assembling,a DMWD model considering the dynamic reliability of multiple subsystems and their synthetic effects on the whole equipment is established.A typical automatic drilling&riveting machine is selected as the research object,and the dynamic weights of reliability of three subsystems are modeled and solved.Subsequently the unknown parameters of the DMWD model are estimated based on maximum likelihood estimation(MLE)and Newton-Raphson method.Finally,the EWH of an automatic station is defined and modeled by using the solved dynamic reliability function.Based on the experimental study on a real automatic drilling&riveting machine from a wing panel assembly station,it is shown that the proposed DMWD and EWH models could effectively calculate the equipment reliability with full consideration of its multiple subsystems.The DMWD model is more suitable for improving the solution precision of EWH than the traditional three-parameter Weibull distribution.展开更多
The specific features of the CAN bus is analyzed and the functional performances in the Controller Area Network(CAN)bus system of Wire Harness Assembly Machine(WHAM)is discussed.A reasonable definition of application ...The specific features of the CAN bus is analyzed and the functional performances in the Controller Area Network(CAN)bus system of Wire Harness Assembly Machine(WHAM)is discussed.A reasonable definition of application layer which is not defined in the CAN specification is given for the control system of WHAM.So application layer planning of CAN bus for dynamic priority is presented.With the mechanism of dynamic priority,it becomes easily to find out the error nodes in the CAN bus system of WHAM and realize multi-mode operation.展开更多
基金This work was supported in part by the Fundamental Research Funds for the Central Universities(Nos.N170303009,N180703007),China.
文摘To improve the accuracy of capacity analysis and prediction for the aircraft assembly stations,an approach for calculating the effective working hour(EWH)of automatic assembly equipment is introduced by using the dynamic mixed Weibull distribution(DMWD)model.Firstly,according to the features of aircraft assembling,a DMWD model considering the dynamic reliability of multiple subsystems and their synthetic effects on the whole equipment is established.A typical automatic drilling&riveting machine is selected as the research object,and the dynamic weights of reliability of three subsystems are modeled and solved.Subsequently the unknown parameters of the DMWD model are estimated based on maximum likelihood estimation(MLE)and Newton-Raphson method.Finally,the EWH of an automatic station is defined and modeled by using the solved dynamic reliability function.Based on the experimental study on a real automatic drilling&riveting machine from a wing panel assembly station,it is shown that the proposed DMWD and EWH models could effectively calculate the equipment reliability with full consideration of its multiple subsystems.The DMWD model is more suitable for improving the solution precision of EWH than the traditional three-parameter Weibull distribution.
文摘The specific features of the CAN bus is analyzed and the functional performances in the Controller Area Network(CAN)bus system of Wire Harness Assembly Machine(WHAM)is discussed.A reasonable definition of application layer which is not defined in the CAN specification is given for the control system of WHAM.So application layer planning of CAN bus for dynamic priority is presented.With the mechanism of dynamic priority,it becomes easily to find out the error nodes in the CAN bus system of WHAM and realize multi-mode operation.
