Development for Autonomous Operation of Ultra-Large Hydraulic Excavators
Hitachi Construction Machinery is developing a wide range of technologies to realize autonomous operation of ultra-large hydraulic excavators at mines.
First, we are working on advanced remote control systems to further improve the working environment and safety of operators. Also, careful checking and operation by operators at mines is conducted to avoid collisions with other equipment and vehicles and to maintain vehicle stability. We are developing operation support systems to maintain these even during remote operation.
Progress toward autonomous driving
Remote Control Systems
A ultra-large excavator "EX2500-6" was remotely operated from a distance of about 870 kilometers in a straight line.
The operator operated the excavator while looking at a screen displayed at Makuhari Messe (Mihama-ku, Chiba City), and remotely operated the excavator at the test site in Urahoro Town, Hokkaido.
This system can also be made remotely not to dig too deep or in the wrong position.
Operation Support System
We have developed operation support system to aim at supporting the digging and loading operations of ultra-large hydraulic excavators for improved operational performance and conducted a verification test at one of Rio Tinto’s mine sites in Australia.
The two operation support systems tested in the verification test are as follows:
Digging Assist function
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.
While experienced operators are able to judge the situation based on the movement of the front attachment and the sounds and vibrations emitted by the hydraulic circuit to reduce the cylinder load, inexperienced operators may be unable to skillfully achieve the same results. This function can automatically perform operations which reduce the cylinder load regardless of the operator's level of experience.
Loading Assist function
The Loading Assist function automatically controls the front attachment when loading material excavated by an ultra-large hydraulic excavator onto the dump truck to help avoid collisions.
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.