Zoomlion Heavy Industry has officially launched the "Smart-Hoist" intelligent control platform for its T6024 and T7030 series flat-top tower cranes. On congested urban construction sites, multiple tower cranes often operate within overlapping radii. Coordinating hook movements between cranes has traditionally relied on radio calls and flag signals between riggers, creating both safety risks and slow lifting cycles. In addition, placing a heavy precast concrete panel into its final position requires "inching" the hook, which with conventional contactor-controlled hoisting motors results in jerky movements that can crack precast elements.
The Smart-Hoist platform addresses both challenges. The engineering centerpiece is the "Laser Mesh Networking" system. Each tower crane in the fleet is equipped with a 360-degree "Scanning Laser Rangefinder" mounted on the tower head, along with a high-precision dual-GNSS base station. The cranes continuously exchange their jib angle, trolley position, and load radius over a dedicated 2.4 GHz encrypted radio channel. The controller builds a live three-dimensional "site occupancy map" of all hook and jib positions. When the path of one crane's load is predicted to intersect with another crane's jib envelope within the next 30 seconds, the system executes a "Gradient Slow-Down": first alerting the operator with a cab display warning, then automatically reducing slewing speed by 50%, and finally locking out the slewing motion entirely if the two envelopes continue to converge. This allows two or even three cranes to safely work overlapping radii without the traditional "priority ladder" rule that wastes waiting time.
The second innovation is the "Micro-Speed Inverter Hoist Control." Traditional two-speed hoisting motors switch between pole pairs, giving the operator only a coarse and fast speed. The Smart-Hoist system replaces this with a variable-frequency drive (VFD) directly driving the hoisting motor. Using the "Encoder Feedback Closed Loop," the system can regulate hook speeds from 0.25 m/min up to full speed with continuous variation. For precision panel placement, the operator activates "Fine Placement Mode" on the remote control. The inverter then limits the hook to a 0.25 m/min crawl, modulated to within 2% accuracy even under swinging loads. Field trials on a 58-story residential project in Changsha demonstrated a 40% reduction in panel placement time and zero anti-collision near-miss events over 11 months of operation.
