The dwell point design of stereo garage conveyer considering load balance

Abstract

By using the non-homogeneous characteristics of the customer arrival process and the characteristics of duration of stay in the garage, we predict the possible standby position of the vehicle conveyer for the next parking or pick-up task during the idle period of the garage and accomplish the design of the dwell point policy. By establishing a garage scheduling model and increasing the weight coefficient of energy consumption, we use the artificial colony algorithm to complete the optimization of the dwell point design policy to realize the load balance of each conveyer. The simulation results show that the average waiting time of customers and the average service time of conveyers are reduced by 20.2% and 62.7%, respectively, which indicates the effectiveness of the design strategy compared with the in-place standby strategy. The standard deviations of load balance of the non-optimized design strategy and the in-place standby strategy are both as high as 50 or more, which shows that the load is unbalanced; on the basis of the total energy consumption of conveyers and customer waiting time increased by 8.6% and 8.0%, respectively, the standard deviation of load balancing decreases by 98% for the optimized design strategy. The designed dwell point policy provides a new idea for improving the load balance of conveyer in stereo garage or warehouse system.

Keywords

• transport engineering
• stereo garage
• load balancing
• artificial bee colony algorithm
• dwell point policy
• operation efficiency