Hitachi Construction Machinery has developed a new operator assist system aimed at supporting the digging and loading operations of ultra-large hydraulic excavators.
The system has been tested at one of Rio Tinto’s Australian mine sites from late March, demonstrating the practical application of the new technology and helping to improve the accuracy of the system going forward.
Sensors, monitors and other equipment were attached to a backhoe EX3600-7 ultra-large hydraulic excavator (operating weight of 360 tonnes) to conduct a performance verification of digging and loading tasks by the operator assist system and verification of the usability of the monitor display installed in the operator cab.
Based on the verification at the site and through insights gained via collaboration with customers, Hitachi is aiming to achieve practical application of the operator assist system in stages from 2025.
“The digging assist function assesses the situation from the load on the hydraulic cylinder and the operation of the front attachment, detected by sensors to automatically improve control of the hydraulic excavator operation according to the situation,” Hitachi said.
“To efficiently excavate material, the amount excavated by each operation must be as optimal as possible. At the same time, when the bucket load during digging becomes excessive, the hydraulic circuit protection function activates to curtail additional digging force and intermittently redirect the operation of the front attachment.”
This function is particularly helpful for newer operators who may not be able to judge situations based on the the movement of the front attachment and the sounds and vibrations from the hydraulic circuit.
“This function can automatically perform operations which reduce the cylinder load regardless of the operator’s level of experience,” Hitachi said.
The same can be said for the loading assist function, which automatically controls the front attachment when loading material excavated by an ultra-large hydraulic excavator onto the dump truck to help avoid collisions.
“Typically, the operator recognises the position, orientation and height of the dump truck body to turn the excavator upper structure and perform the loading work while operating the front attachment,” Hitachi said.
“To avoid contact and collisions with the dump truck and surrounding structures during the loading work, the operator must combine the operation to raise the front attachment of the hydraulic excavator with the operation to swing the upper structure. This combined operation poses a high degree of difficulty for inexperienced operators and even experienced operators require a high level of concentration.
“Since this function automatically performs the operation to raise the front attachment, the operator can concentrate on just the swing operation, which reduces mental load on the operator.”
Going forward, the Hitachi Construction Machinery Group will continue to strive to solve customer issues as “a true solutions provider” to help increase safety and productivity and reduce the life cycle cost of customer machinery through collaboration with customers.