To enable the efficient division of labor in container yards, many large ports apply twin cranes, two identical automated stacking cranes each dedicated to one of the transfer zones on the seaside and landside. The use of a handshake area, a bay of containers that separates the dedicated areas of the two cranes, is a simple means to avoid crane interference. Inbound containers arriving in the transfer zone of one crane and dedicated to a stacking position of the other crane’s area are placed intermediately in the handshake area by the first crane and then taken over by the second crane, and vice versa for outbound containers. Existing research only evaluates simple heuristics and rule-based approaches for the coordination of twin cranes interconnected by a handshake area. For this setting, accounting for precedence constraints due to stacking containers in the handshake area, we derive exact solution procedures under a makespan minimization objective. In this way, a comprehensive computational evaluation is enabled, which benchmarks heuristics with optimal solutions and additionally compares alternative crane settings (i.e., without workload sharing and cooperation with flexible handover). We further provide insights into where to position the handshake area. Our results reveal that when planning is too simple (i.e., with a rule-based approach), optimality gaps become large, but with sophisticated optimization, the price of a simplified crane coordination via a handshake area is low.

为了实现集装箱堆场的高效分工，许多大型港口采用双起重机，两台相同的自动堆垛起重机，每台专用于海边和陆侧的转运区之一。使用握手区，即分隔两台起重机专用区域的集装箱托架，是避免起重机干扰的简单方法。到达一台起重机的转运区并专用于另一台起重机区域的堆垛位置的入站集装箱由第一台起重机中间放置在握手区，然后由第二台起重机接管，对于出站集装箱反之亦然。现有研究仅评估简单的启发式方法和基于规则的方法，用于协调由握手区域互连的双起重机。对于此设置，考虑到由于在握手区域堆叠容器而导致的优先约束，我们在最小化完工时间目标下推导出精确的解决方案。通过这种方式，可以进行全面的计算评估，它使用最佳解决方案对启发式进行基准测试，并另外比较备选起重机设置（即，没有工作负载共享和灵活切换的合作）。我们进一步提供了有关握手区域放置位置的见解。我们的结果表明，当规划太简单（即，使用基于规则的方法）时，优化差距会变大，但通过复杂的优化，通过握手区域简化起重机协调的价格很低。启用了全面的计算评估，它使用最佳解决方案对启发式进行基准测试，并另外比较替代起重机设置（即，没有工作负载共享和灵活切换的合作）。我们进一步提供了有关握手区域放置位置的见解。我们的结果表明，当规划太简单（即，使用基于规则的方法）时，优化差距会变大，但通过复杂的优化，通过握手区域简化起重机协调的价格很低。启用了全面的计算评估，它使用最佳解决方案对启发式进行基准测试，并另外比较替代起重机设置（即，没有工作负载共享和灵活切换的合作）。我们进一步提供了有关握手区域放置位置的见解。我们的结果表明，当规划太简单（即，使用基于规则的方法）时，优化差距会变大，但通过复杂的优化，通过握手区域简化起重机协调的价格很低。