Automated storage and retrieval system reducing bin moves by selecting multi-stock bins containing highest number of SKUs on workstation stock waitlist

A method of controlling a robot in an automated storage and retrieval system, the method comprising:

• storing a plurality of records indicating stock-keeping units (SKUs) for which there is stock in each bin of a bin storage facility having a plurality of bins physically stored therein, the plurality of the bins in the bin storage facility being multi-stock bins that hold stock for a plurality of different stock-keeping units (SKUs);
• tracking a stock waitlist for a plurality of workstations, the stock waitlist indicating quantities of required stock-keeping units (SKUs) still required to be delivered to each of the workstations in order to fulfill the current orders assigned to the thereto, the workstations being locations at which a picking agent picks stock from the bins of the bin storage facility in order to fulfill the current orders assigned thereto;
• receive pending orders from an order system, each of the pending orders specifying quantities of desired stock-keeping units (SKUs);
• for each pending order, determine a workstation, based on the stock waitlist corresponding to each of the workstations, to assign the pending order, such that the number of bins required to be delivered to the workstation to fulfill the pending order is minimized;
• calculate order weights respectively corresponding to each of the pending orders, and wherein the order weights are calculated as a function of a number of bins that would need to be delivered to the workstation assuming the pending order is assigned to the workstation, items picked per bin presentation (IPP), a predetermined global factor for IPP, current processing time for an order, a predetermined global factor for current processing time, order priority, and a predetermined global factor for order priority;
• and
• compare the order weights of the pending orders and assign a highest-weighted pending order to the workstation.

A controller of an automated storage and retrieval system, the controller comprising at least one processor configured by executed software loaded from a storage medium to:

• store a plurality of records indicating particular stock-keeping units (SKUs) for which there is stock in each bin of a bin storage facility having a plurality of bins physically stored therein, the plurality of the bins in the bin storage facility being multi-stock bins that hold stock for a plurality of different stock-keeping units (SKUs);
• track a stock waitlist for a plurality of workstations, the stock waitlist indicating quantities of required stock-keeping units (SKUs) still required to be delivered to each of the workstations in order to fulfill the current orders assigned thereto, the workstations being locations at which a picking agent picks stock from the bins of the bin storage facility in order to fulfill the current orders assigned thereto;
• receive pending orders from an order system, each of the pending orders specifying quantities of desired stock-keeping units (SKUs);
• for each pending order, determine a workstation, based on the stock waitlist corresponding to each of the workstations, to assign the pending order, such that the number of bins required to be delivered to the workstation to fulfill the pending order is minimized;
• calculate order weights respectively corresponding to each of the pending orders, and wherein the order weights are calculated as a function of a number of bins that would need to be delivered to the workstation assuming the pending order is assigned to the workstation, items picked per bin presentation (IPP), a predetermined global factor for IPP, current processing time for an order, a predetermined global factor for current processing time, order priority, and a predetermined global factor for order priority;
• and
• compare the order weights of the pending orders and assign a highest-weighted pending order to the workstation.

A non-transitory computer-readable storage medium comprising processer computer executable instructions, that when executed by at least processor, cause the processor to:

• store a plurality of records indicating a particular one or more stock-keeping units (SKUs) for which there is stock in each bin of a bin storage facility having a plurality of bins physically stored therein, the plurality of the bins in the bin storage facility being multi-stock bins that hold stock for a plurality of different stock-keeping units (SKUs);
• track a stock waitlist for a plurality of workstations, the stock waitlist indicating quantities of one or more required stock-keeping units (SKUs) still required to be delivered to each of the workstations in order to fulfill the current orders assigned thereto, the workstations being locations at which a picking agent picks stock from the bins of the bin storage facility in order to fulfill the current orders assigned thereto;
• receive pending orders from an order system, each of the pending orders specifying quantities of desired stock-keeping units (SKUs);
• for each pending order, determine a workstation, based on the stock waitlist corresponding to each of the workstations, to assign the pending order, such that the number of bins required to be delivered to the workstation to fulfill the pending order is minimized;
• calculate order weights respectively corresponding to each of the pending orders, and wherein the order weights are calculated as a function of a number of bins that would need to be delivered to the workstation assuming the pending order is assigned to the workstation, items picked per bin presentation (IPP), a predetermined global factor for IPP, current processing time for an order, a predetermined global factor for current processing time, order priority, and a predetermined global factor for order priority;
• and
• compare the order weights of the pending orders and assign a highest-weighted pending order to the workstation.