AGV or Lift-AGV? Performance trade-offs and design insights for container terminals with robotized transport vehicle technology

Abstract

A. Service time expressions for nodes SQ and QS (u −1 sq , cv 2 sq , u −1 qs , cv 2 qs )

Emerging technology and management research in the container terminals: Trends and the COVID-19 pandemic impacts

“…Although LAGV requires less coordination with other terminal equipment, it still has a high container handling time. Hence, Kumawat and Roy (2021) investigated the effect of such trade-offs on terminal performance under various design parameter settings, and compared LAGV with standard AGV. It is worth mentioning that this way of operation is very similar to SC/ALV which can decouple the handshakes with QCs and YCs.…”

Petri‐net‐based deadlock detection and recovery for control of interacting equipment in automated container terminals

“…For intra-terminal operations, L-AGVs represent a recent development in transportation technology. As innovative robotized transport vehicles, L-AGVs are deployed by a few newly developed ACTs (e.g., Qingdao Qianwan container terminal, China) and promise a better coordination mechanism of transport vehicles with AYCs [20,11]. In modern ACTs equipped with L-AGVs, some racks (or frames) of TPs are settled in TAs at yard side so that containers can be stored and retrieved through these racks.…”

“…However, an L-AGV would increase the overall transfer time of containers between itself and AYCs, because the hoisting and setting down of containers regarding TAs are double handled. It is interesting and challenging to study the trade-offs between the waiting time and the container handling time with respect to L-AGVs under different design parameter settings [11].…”

“…In this paper, we investigate automated seaport container terminals that employ AGVs with the capability of lifting a container temporarily buffered at the TA in front of a storage block. These AGVs are called lift-AGVs (L-AGVs for short) and are under development [11,5]. Nearly all techniques for deadlock supervisory control, including avoidance and prevention, have already been addressed for transport operations in ACTs [12][13][14][15][16][17].…”

“…Additionally, few of the existing deadlock detection and resolution approaches can be easily adapted to handle the complicated situation where multiple types of interacting equipment units work simultaneously. Enlightened by the work in [15] and others including [11,16,18,19], this paper studies the deadlock problem occurring in the EIS of ACTs equipped with L-AGVs. By taking the Petri net formalism typically as a basic modelling paradigm, we establish the formal model for the EIS operations, then characterize deadlock as some graphical objects at a system state.…”