A gantry robot works inside a rectangular envelope set by its frame, while an AGV moves freely between shops with limited stopping accuracy. Where the two meet is often the weakest link in the material flow. Each machine runs reliably alone, yet the handover still suffers waiting, misalignment and retries, and the cause is usually the interface design.

The handover sits at the edge of the gantry envelope, built as a transfer table or buffer with locating features. AGV stopping accuracy is typically five to ten millimetres, while gripping often needs one millimetre or better. Pins, V-blocks or guide bars let the carrier correct itself as it lands, leaving precision to the structure rather than the vehicle.

The interface decides whether the two sides cooperate. The fleet manager asks the gantry controller for permission to enter; the controller answers whether entry is allowed and whether it is busy. A typical handshake has five states: arrived, entry permitted, handling, complete and released, and any timeout should drive a safe state. A clear state machine matters more than hard wiring or a fieldbus.

Cycle time must be calculated. Handling time per part times parts per trip gives how long the robot holds the position; AGV round-trip time divided by that figure gives the vehicles needed to avoid waiting. One extra buffer is usually added so a vehicle can drop and leave. Too few buffers pass every fluctuation straight down the line.

Carrier standardisation is often overlooked. If pallets vary, frames distort or stack heights differ, taught points cannot be reused. Carriers should be managed as tooling, with defined locating faces, gripping clearance and maximum offset, plus mechanical stops on the table. Better consistency raises the reuse of taught points and shortens commissioning.

Safety is organised by zone. Where a gantry robot and AGVs share floor space, the handover area needs light curtains or area scanners: the vehicle confirms the robot has left before entering, and the robot confirms the vehicle has cleared before working. E-stops should be interlocked so either side stops both, and a hardwired circuit remains the last layer.

Exception handling decides whether the system is usable. Late vehicles, lost communication, failed grips and shifted carriers all happen on site. Set timeout thresholds; on timeout the robot turns to other tasks or waits and reports to the fleet manager instead of standing still. Keep a manual release path so an operator can clear the fault after confirming safety.

Coordination is essentially connecting two independent machines, physically and in information terms. In its truss manipulator, gantry robot, truck loading, AS/RS and seventh-axis projects, Truman considers transfer table design, signal handshakes and cycle calculations together at the concept stage, so the handover is no longer the bottleneck.