Fully Automatic Hoisting Cycles: Pickup, Transport & Placement
📋 Key Summary
Fully automatic hoisting means the overhead crane completes the entire cycle of "pickup, lifting, transport, lowering, and placement" on its own, with no human intervention in between. It links automatic positioning, automatic pickup, automatic transport, and automatic placement into a closed loop, then interfaces with conveyor lines and AGVs. This article explains how the four stages of the cycle are connected and what it takes to put the system into practice.
📌 The Four-Stage Cycle
Pickup → Hoisting → Transport → Placement — the four stages run end-to-end and repeat continuously.
If any single stage fails, the entire automatic cycle comes to a halt.
In steel mills, warehouses, and automotive plants, there is a type of overhead crane that repeats the same motions day in and day out: picking up a load at point A, lifting it, moving it to point B, and setting it down — hundreds or even thousands of times per shift. This repetitive work is exactly what fully automatic hoisting is designed to take over.
Fully automatic hoisting is not a single technology. It links positioning, pickup, transport, and placement into a closed loop so the crane can run the entire cycle by itself. Below, we break down how this cycle is implemented in practice.
Four Stages of Automatic Hoisting: Pickup, Lift, Move, Place
The fully automatic hoisting cycle consists of four stages connected end-to-end.
Pickup — the crane automatically aligns with the suspended load and engages the lifting spreader. This requires automatic positioning plus automatic centering so the hook lines up precisely with the lifting point.
Hoisting — the load leaves the ground smoothly. Anti-sway and shock suppression are essential to keep the load stable as it rises, with no swinging or collision risk.
Transport — the load is moved along a planned path to its destination. This calls for automatic path planning and anti-collision protection so the crane navigates safely around obstacles.
Placement — the load is aligned with the target position and lowered gently. Precise positioning at the set-down point and impact-free lowering are both critical. Each of the four stages must be automated — none can be skipped — and ISO 24617, Intelligent Control System for Cranes, provides a framework for automatic operation.
Closing the Loop: Sequence Control and Condition-Based Interlocking
Automating each stage in isolation is not enough — the key is linking them into a continuous cycle.
Sequence control executes the four stages in a fixed order: pickup must be completed before hoisting begins, hoisting must reach its target before transport starts, and transport must finish before placement can occur. The completion of each stage is the trigger condition for the next.
Condition-based interlocking uses sensor signals to hand off from one stage to the next. The pickup-complete signal triggers hoisting; the hoisting-complete signal triggers transport. Each link depends on the previous one — if a signal is missing, the next action simply does not start.
This "finish one, start the next" interlocking logic is the core of the automatic cycle. Kelude Heavy Industry uses sequence control combined with condition-based interlocking to tie the four stages into a closed loop.
Integrating with the Production Line: Conveyor and AGV Coordination
The real value of fully automatic hoisting only shows up when viewed within the context of the entire production line.
The overhead crane does not work in isolation — it must coordinate with conveyor lines, AGVs, and RGV systems. The crane lifts a load to the side of a conveyor line, and the conveyor takes it away; or the crane picks material off an AGV and places it at a workstation.
This coordination is driven by interface signals: the crane sends an in-position signal to the conveyor, the conveyor sends a ready signal back to the crane, and only after this handshake does either side act. Interface protocols must be aligned and timing must be matched. GB/T 28264-2017 Safety Monitoring and Management System for Lifting Appliances sets requirements for recording operating status data.
Kelude Heavy Industry treats crane-to-conveyor and crane-to-AGV integration as the final link in the fully automatic hoisting chain. No matter how well the crane automation performs, if it cannot connect to the production line, the value is diminished.
Common Mistakes in Implementing Automatic Hoisting Cycles
Mistake #1: Automating individual stages without closing the loop. Pickup and transport may each be automated, but if they are not linked into a closed cycle and a human still has to bridge the gaps manually, the automation delivers little benefit. The system must be designed around the complete cycle.
Mistake #2: Signals between stages are not closed-loop. If pickup completion is not confirmed by a feedback signal, hoisting may start blindly, leading to collisions or unintended motion. Every stage must have a positive in-position signal.
Mistake #3: Ignoring production line integration. The crane cycle may run smoothly on its own, but if the interfaces with conveyor lines and AGVs are not aligned, material flow breaks down. Kelude Heavy Industry treats production line integration as an acceptance criterion for fully automatic hoisting — if the interface does not pass, the job is not considered complete.
Automation Checklist for the Four Stages
| Stage | automationCritical Aspect | Technology Dependency | Completion Signal | Trigger Next Stage |
|---|---|---|---|---|
| Grabbing | Positioningshaft alignmentHookingLifting spreader | Positioningshaft alignment | Load Secured | Hoisting / Lifting |
| Hoisting / Lifting | Anti-swayControlled Lift-Off | anti-sway control | Hoisting / LiftingLoad Secured | Transporting |
| Transporting | Path Planninganti-collision | Path Planning | Positioned for Transport | Placing |
| Placing | Target Alignment & Controlled Lowering | Positioningshaft alignment | Placement Complete | Return to Grab |
Quick Reference of Standard Clauses for Automatic Hoisting Cycles
| Standard | Clause Essentials | Relationship with Automatic Cycle |
|---|---|---|
| ISO 24617 | intelligent control system for cranes | automatic operationFramework |
| GB/T 28264 Safety Monitoring and Management System | safety monitoringTraceabilityrequirements | Cycle Operation Logging |
| FEM 1.001 Crane Design Standard | crane design specification | operating stabilityReference Point |
FAQ: Fully Automatic Hoisting Cycles
Q: What standards apply to automatic hoisting cycles?
A: The automatic operation framework follows ISO 24617, cycle traceability complies with GB/T 28264-2017, and operating stability benchmarks reference FEM 1.001. These standards define the constraints for the operating framework, status logging, and stability of automatic cycles. For implementation, the four stages must form a closed loop with a position-confirmation signal at each stage — this is a prerequisite for the automatic cycle to run.
Q: How do I know if my application is suited to fully automatic hoisting?
A: Look at the repetitiveness and consistency of the operation. If hoisting tasks are highly repetitive — hundreds or thousands of cycles per day with fixed paths and uniform loads — fully automatic operation is a good fit. Conversely, if lifts vary widely, loads are irregular, and no two cycles are alike, automation becomes difficult and delivers low returns. The key criterion is the "cyclic operation" characteristic: only repetitive, stable tasks justify full automation.
Q: Why do fully automatic hoisting cycles often stall midway?
A: The usual cause is a missing closed-loop signal between stages. If the grab/attach stage doesn't send a completion signal, hoisting won't start; if the transfer position isn't confirmed, the placement stage won't execute — and the cycle stalls. Another common issue is a misaligned interface with the production line: the overhead crane arrives but the conveyor line isn't ready. When troubleshooting a stall, first check the position signals between stages, then verify the handshake signal with the production line.
Fully automatic hoisting often works in coordination with AGVs and RGVs. For multi-vehicle coordination strategies, refer to AGV/RGV and Overhead Crane Multi-Vehicle Coordination: Smart Factory Unmanned Dispatching System in Practice.
The value of fully automatic hoisting lies in handing repetitive work to machines. Kelude links grabbing, hoisting, transferring, and placing into a closed loop with inter-stage signal coordination, then integrates with the production line — letting the overhead crane run the entire cycle on its own.
