Advanced Duty Detection System

An advanced duty detection system has been developed and demonstrated that will continuously monitor dragline operation and identify and classify operating practices that cause excessive amounts of incremental damage or duty on the machine. The system will form part of and extend the functionality of the Dragline Dutymeter system developed as part of the ACARP project C9034.

Dragline field tests show that there are significant differences between operating practices in terms of damage to the machine. In order to improve and control operator practices a Dragline Dutymeter system was developed and tested. The Dutymeter is a computer based sensor system designed to continuously monitor the operation of and estimate the incremental damage experienced by a dragline during routine operation. This project extends the functionality of the Dragline Dutymeter by providing more effective feedback to the operator via the detection and classification of particular operator practices that cause excessive amounts of duty.

One of the benefits to the industry that would result from successful utilisation of the project outcomes is an estimated increase in the suspended load capacity of up to 25% without suffering a noticeable degradation in the machine reliability and availability.

An important contribution of the ADDS is the breakdown of duty into load and operator dependent components. The results of offline testing of the ADDS indicate that bucket weight contributes only 52% of the total duty inflicted on the machine, with 28% of the damage being caused by swinging the bucket out of the boom plane and 15% being caused by boom shake at greater than 1Hz, which is caused by rough operation. Over one in four cycles contain an identifiable extra contribution to fatigue that is separate from the main loading cycle. These incidents contribute 10% of the total duty and it should be possible to eliminate them completely. In many cycles of operation the duty incurred is not significantly greater than would be expected from the bucket load alone while other cycles incur more than three times this amount of duty, indicating significant potential for improvement in operator performance with adequate feedback.