Smart Grab Control

Let's grab the future!

About the backstory

To excavate deep trenches in the soil for cut-off walls and supporting walls, special grabs known as mechanical diaphragm walling grabs have been used for some time now. These are operated when suspended freely from the ropes of a duty-cycle crane and controlled entirely by winding and unwinding the two ropes that are used. The manual operation to execute this function requires a great deal of finesse and experience, often necessitating multiple years of training. One particularly challenging task is controlling the two rope winches using hydraulic pedals that generate traction between the winch drum and winch motor using a multi-plate clutch. This needs to be coordinated with the hand lever movements and requires an extremely sensitive touch.

Mechanical rope grabs have been successfully used in practice for many years and are very productive in the hands of an experienced operator, but they place a great deal of strain on the operator due to the constant high level of concentration demanded.

Innovation Smart Grab Control (SGC)

The goal of the development presented here is to provide a system that allows even operators with less experience to work safely and efficiently with this type of diaphragm walling grab. The aim is to considerably simplify operation from the duty-cycle crane while at the same time increasing safety on the site and comfort levels for the operator.

The SGC system encompasses the following assistants and functions:

Grab lowering booster

Fast lowering of grab using joystick with free-fall assistance

Grab filling assistant

Semi-automatic filling of grab buckets with various predefined settings

Grab twisting assistant

Precisely controlled twisting of the grab, no uncontrolled rotation

Grab emptying assistant

Ensures an unchanged dumping height for the grab during the emptying process

Quick emptying button

To empty the buckets quickly, various speeds can be selected

Plank releasing assistant

Semi-automatic chiseling of facing concrete on the diaphragm wall plank

Boulder detection

Prevents the buckets from jamming when grabbing large bodies of rock in the trench

Safe operation without years of training

With the help of these assistants, even operators with less experience can safely operate the rope grab. The learning and training process which often takes years can be noticeably reduced

Safety is considerably enhanced by the system. Operator errors and resulting uncontrolled movements of the grab are nearly excluded. The system monitors the position of the grab using path measurement and does not permit unintentional falling, for example. 

With regard to ergonomics, the operating experience is markedly improved when using the system. The operator no longer needs to constantly stand on the hydraulic foot pedals, which require a high activation force due to the structural design. Operation with the help of SGC now exclusively relies on hand lever movements and buttons. The physical and mental strain on the operator is reduced, and operating comfort increases. The adapted and extended visualization of work processes on the screen enables precise tracking of individual work steps in real time.

Your benefits at a glance

  • Improved safety
  • Optimized efficiency
  • Simplified operation
  • Shorter learning phase
  • Improved ergonomics and comfort

Want to learn even more?

Check out our long interview “Let’s grab the future – how our Smart Grab Control is revolutionizing the world of mechanic diaphragm walling grabs” with David Pfeiffer, the project’s technical supervisor

Go to interview