Trackshield Collision Avoidance System

Researchers from CRCMining, led by Professor Ross McAree and working with P&H MinePro Services, have developed the Trackshield Collision Control System, a computer system to minimise the frequency of bucket and track collisions on electric mining shovels. Prior to each digging motion, the bucket is repositioned between the crawler tracks in a process known as ‘tucking’. During ‘tucking’, the bucket comes in close to the tracks and risks significant damage to the machine if it hits the crawler tracks.
According to Professor McAree, bucket strikes are among the most damaging incidents that could happen to a mining shovel during regular operation.
“Bucket collisions are most commonly the result of operator misjudgement and even the most competent operator can hit the bucket once or twice during a long shift,” he said.
“Collisions between the bucket and tracks cause damage to the machinery, generating a loss of production due to unplanned down time and significantly reducing the operating life of a shovel.
“The immediate consequence of a bucket strike is the fracture of one or more of the crawler shoes but incremental damage is also caused to the car-body structure, the handle, the crowd transmission and the swing transmission.”
The Trackshield system comprises computer hardware that is mounted on the shovel, computer software that runs the hardware and a suite of sensors to determine where the bucket is in relation to the tracks.
Professor McAree said the unique technology uses a predictive control framework to prevent collisions.
“The system predicts future locations of the bucket using a set of mathematical models that are driven by the operator’s joystick commands,” he said.
“If impact is predicted, the collision prevention algorithms calculate the minimum change needed to the operator’s command that will avoid the collision by a specified clearance distance.
“The altered joystick references are then passed on to the shovel’s control system.”
At the 2009 Australian Mining Technology Conference, University of Queensland Postgraduate student Michael Kearney reported on some of the latest developments in the technology.
“With the latest advances in our algorithms, we think we have some really exciting opportunities to extend this technology beyond collisions with the tracks to avoiding collisions between shovels and trucks. This is probably one of the most advanced application of model predictive control ideas applied to machinery and is at the vanguard of technology developments in mining automation“
The Trackshield Control System is currently being commercialised by P&H MinePro Services and is expected to be installed on shovels around the world.