含缓存池的立体车库并行存车方案设计与分析

为了缓解高峰期停车难、排队等待时间长和立体车库存车效率低的问题，提出一种具有缓存功能的立体车库。首先，充分利用立体车库底层空间设计子母车缓存池存车方案，通过缓存池的连续搬运工作提高存取车效率。由于车库各层均布置有一辆母车，提出多层循环车位分配策略，实现车库多层母车并行存车功能，并通过分析多个存车请求下立体车库的工作时序特征计算立体车库并行存车效率。其次，基于顾客存车流程建立M/M/n存车排队模型，并采用排队理论分析不同顾客到达速率下升降货梯平均利用率，不同升降货梯数量下顾客存车平均排队的时间、队长和需要等待的概率。最后，结合实际车辆参数、车库结构尺寸和子母车搬运系统的运动参数，并基于占地面积合理设计存车缓存池容量，对比分析缓存池作用前后的顾客存车指标，验证了缓存池能够大幅降低顾客存车等待时间。结果表明：立体车库系统在进行5辆车并行存车状态下，比传统的堆垛机式立体车库存车效率提升39%；顾客到达速率为75辆/h，设置存车的子车缓存池容量为4，可节省顾客约47.8%的平均排队时间。因此，该含有缓存池的立体车库并行存车方案能显著提高存车效率，同时降低顾客等待时间，可进一步满足顾客存车需求。

Design and Analysis of Parallel Storage Vehicle Scheme of Stereo Garage with Buffer Pool

In order to alleviate the problems of difficult parking in rush hours, long waiting time in queue and low efficiency of stereo vehicles, a stereo garage with efficient parallel storage is designed. First of all, make full use of the three-dimensional garage bottom space to design sub-mother vehicle buffer pool storage scheme, through the buffer pool continuous handling work to improve the efficiency of vehicle storage and extraction. Since there is a mother vehicle in each layer of the garage, a multi-layer cycle parking allocation strategy is proposed to realize the parallel storage function of the multi-layer mother vehicle in the garage. The parallel storage efficiency of the stereo garage is calculated by analyzing the working sequence characteristics of the stereo garage under multiple storage requests. Secondly, the M / M / n queuing model for vehicle storage is established based on the customer''s vehicle storage process, and the queuing theory is used to analyze the average utilization rate of elevators under different customer arrival rates, and the average queuing time, queue length and the probability of waiting for customers under different number of elevators. Finally, combined with the actual vehicle parameters, garage structure size and the movement parameters of the sub-mother vehicle handling system, and based on the occupied area of stereo garage, the capacity of the vehicle storage buffer pool is reasonably designed, and the customer vehicle storage indexes before and after the buffer pool are compared and analyzed. It is verified that the buffer pool can significantly reduce the customer waiting time for vehicle storage. The results show that the storage efficiency of the stereo garage system is 39 % higher than that of the traditional stacker stereo garage under the condition of 5 vehicles parallel storage. The customer vehicle arrival rate is 75 vehicles / h, and the capacity of the sub-car buffer pool is set to 4, which can save about 47.8 % of the average queuing time of customers. Therefore, the parallel car storage scheme of the stereo garage with buffer pool can significantly improve the efficiency of car storage, and reduce customer waiting time, which can further meet customer demand for car storage.