ACARP ACARP ACARP ACARP
Open Cut

Shovel Load Assist Project

Open Cut » Maintenance & Equipment

Published: July 16Project Number: C16031

Get ReportAuthor: John Dudley and Ross McAree | CRCMining

This project, also known as SLAP, commenced in 2007 with the vision to develop an autonomous mining shovel that was able to:

· automatically dig material without requiring human involvement;

· load this material into trucks in such a way that the tray capacity is fully utilized and the load is equally distributed;

· manage the dig face and floor to ensure compliance with the mine plan and the maintenance of a favorable bench for excavation;

· have sufficient awareness to avoid self-collisions, e.g. track strikes;

· have sufficient situational awareness to know the activities of equipment operating in its surrounds and use this knowledge in its own decision making, including avoiding collisions with other equipment, notably the haul-trucks being loaded and bulldozers doing clean up work around the machine;

· monitor machine productivity, e.g. cycles times, payloads, and so on;

· employ the on-board sensors used for automation to build local maps of terrain that feed into the mine plan and allow informed automated decision making;

· determine the tactical plan to be used in excavating blocks of material including decisions about when to reposition, where to move to, and what material to take from a position;

· manage overall activity in the load area, including scheduling  of  work,  e.g.   the arrival and dispatch of trucks from loading positions, scheduling floor cleanup, and so on;

· be capable of performing ancillary functions such as management of trailing electrical cable,

· automated parking of the machine to allow access, etc.; and

· have a human-machine interface that enables its effective use.

 

The participants in the project were the Smart Machines Group at the University of Queensland, the Australian Centre for Field Robotics at the University of Sydney, both through the CRCMining, CSIRO, and Joy Global Surface Mining Equipment (previously P&H Mining Equipment).  

 

The strategy adopted for working towards the vision of an autonomous mining shovel was by a series of stepping stone technologies, each of which would contribute to the overall goal whilst having a value proposition to the open-cut coal sector as a useful technology in its own right.  The name of the project deliberately included the word 'assist' to capture the notion that while the long term goal was full automation of mining shovels, the pathway to achieving this was to be by a series of semi-automation technologies that would assist the operator achieve higher safety and productivity.  

 

The project identified and developed five key stepping stone technologies

· TrackShield: A safety related operator assist technology that helps operators avoid self collisions, focussing on collisions between the shovel dipper and tracks.

· TruckShield: A safety-related operator assist technology that provides an engineered layer of protection against high-energy collisions between shovels and trucks.

· DozerShield: A safety-related operator assist technology provides an engineered layer of protection against high-energy collisions between shovels and the clean-up dozer.

· AutoSwing: An operator assist technology providing a semi-automation layer that allows the swing, dump and return phases of the shovel cycle to be performed autonomously.

· AutoFill: An assistive technology providing a near-full-automation layer that allows the dig, swing, dump and return phases of the shovel cycle to be performed autonomously.

 

These five technologies represent increasing levels of automation, with AutoFill providing near complete automation of typical truck loading activities. The project was conducted in four phases: The first three phases focussed on the development of Trackshield, TruckShield, DozerShield and AutoSwing. The first phase developed proof-of-concept systems on a P&H2100BLE shovel that was installed at Bracalba Quarry, near Caboolture, for the purpose of the project. Phase 2 addressed and closed  knowledge and technology gaps identified in the work of Phase 1. Phase 3 trialled the technologies in a production environment at Lake Lindsay mine in Central Queensland.  AutoFill was developed and tested as Phase 4 of the SLAP project at Bracalba Quarry on the P&H2100BLE.  Throughout, the project conducted its activities within the functional safety lifecycle frameworks of AS61508 and AS62061.

 

Progress on the first technology, TrackShield, had been made in a precursor project - C15038 Collision Control and Avoidance for Electric Mining Shovels - which addressed the problem of avoiding self collisions. This technology continued to mature during the SLAP Project to become a product now commercially available from Joy Surface Mining for their mining shovels with sales of the product globally.

 

Truckshield is an extension of the TrackShield concept with the purpose of managing the inherent risks associated with loading of haul trucks by electric mining shovels.

 

A significant research question that the SLAP project addressed was accurate and reliable determination of the position of trucks (and other equipment) relative to the shovel.  A  redundant truck pose estimation system was developed that used three technologies that had a minimal set of common-cause failure modes to determine the position of trucks relative to the shovel: (i) inertially aided high-precision GNSS trilateration; (ii) ultra-wideband ranging transceivers mounted to trucks and the shovel; and (iii) shovel mounted LiDAR sensors that determined truck position from point clouds generated by the sensor. The system requires agreement of two of the three systems and is capable of estimating the six dimensional position and orientation of trucks being loaded with sufficient accuracy that no point on the body of the truck is more 0.3m from where the system estimates it to be, with availabilities of 99.99% when the truck was stationary and 0.5m with availabilities of 98.97% when the truck was in motion.

 

Field trials of TruckShield conducted on a P&H4100XPB and Komatsu 830e truck at Lake Lindsay mine in Central Queensland demonstrated that TrackShield can address the risks of truck strikes with no observable detrimental impact on cycle times when compared with manual operation.

 

Dozershield was a further extension of the TruckShield/TrackShield concept to clean-up equipment operating around the shovel.  Currently, operations must rely on either procedural or alarm based solutions to manage the risk of dozers performing clean-up around shovels. Again, a significant challenge is determining the six-dimension spatial pose of the dozer relative to the shovel and also predicting its likely future motions.  

 

The project has demonstrated, through field trials of DozerShield at Lake Lindsay mine using a P&H4100XPB Shovel and a Caterpillar D11 Dozer doing clean-up work, that a hard engineering control can be applied to reduce the risk of collision between shovel and dozer. Because DozerShield inhibits shovel motion when a sufficiently high probability of collision is detected, it introduces operational delays. Extrapolating the activation delays observed during trials suggests DozerShield would introduce delays of approximately 400s per shift.  However, these larger than expected delays were due to the large number of activations observed and DozerShield delays are expected to be considerably less when paired with higher compliance to SOP and advanced warning of the dozer operator.   

 

TruckShield, DozerShield and AutoSwing are designed to reduce the frequency and severity of collisions.  These technologies alter the health and safety risk profile of shovel operation but also have the potential to influence value by reducing equipment downtime, reducing repair costs, etc.  The expected value of these savings is directly linked to the frequency of the event occurring and the potential that the technology has to reduce that frequency.  The integrity and functionality that the technology provides thus influence both value and risk in a closely coupled manner.  

 

For AutoSwing, however, there are also capabilities that the technology provides that influence value without a corresponding impact on risk, e.g. faster swing times. Field trials of AutoSwing at Lake Lindsay mine showed that The autonomous loading of trucks is feasible and results obtained predict a 11.5% reduction in swing time equivalent to 1.4 second per loading cycle. Moreover, smoother machine response observed in swing armature current with predicted benefits to machine duty.

 

AutoFill extends the functionality of AutoSwing by adding an autonomous digging capability.  Under control of AutoFill, the shovel can complete fully autonomous truck loading passes without operator intervention. The scope of AutoFill includes: dig selection, digging, swinging, dump point selection, dumping, and returning to tuck. During trials of Autofill it was demonstrated to be robust in detecting the presence of the truck on its arrival, identifying a dig strategy (i.e. where to dig from), executing this strategy, monitoring the material excavated after each dig, planning where to dump to equalize tyre loading and updating the excavation sequence for a truck being loaded in real-time to accommodate for variations.

 

The value proposition for TruckShield, DozerShield and AutoSwing was investigated   as  part of the project scope. DozerShield and AutoSwing present strong value propositions while TruckShield is an attractive solution along the path to automation. Using parameters typical of a Central Queensland Coal mine, the per-shovel, net present value of these technologies was estimated to be $10.7m with a payback period of 3 years in unconstrained production setting and $1.5m with a payback period of 7 years in a constrained production setting.

 

Through the SLAP project, what, in 2007, seemed an ambitious vision for a future autonomous mining excavator now seems within the reach of existing knowledge and technology.  Achieving it, will of course take a continued effort by stakeholders, with the likely pathway being by through realizing of incremental stepping stones over time, e.g. DozerShield, TruckShield, AutoSwing, AutoFill, then the autonomous mining shovel.

Underground

Health and safety, productivity and environment initiatives.

Recently Completed Projects

C21013Improving Cavity Prediction On Longwall Faces Through A Combination Of Reliable Convergence, Canopy Attitude And Leg Pressure Monitoring

Most Australian coal mines have shield leg pressure monitoring in real t...

C24014Distributed Acoustic Conveyor Monitoring

CRC Mining have investigated the application of fibre optic Distribu...

C25054Distributed Acoustic Conveyor Monitoring - Phase 2

This project is phase 2 of the distributed acoustic sensing project ...

Underground

Open Cut

Safety, productivity and the right to operate are priorities for open cut mine research.

Recently Completed Projects

C23053A Study Of Sustainability And Profitability Of Grazing On Mine Rehabilitated Land In The Upper Hunter NSW

This study was initiated by the Upper Hunter Mining Dialogue (UHMD) ...

C25035Coal Subsurface Mapping For Open Cut Selective Mining

A reliable coal seam sensing system is required to improve the produ...

C23025Coal Pit Lake Closure By River Flow Through: Risks And Opportunities

In 2011, the river diversion channel around Lake Kepwari, a former o...

Open Cut

Coal Preparation

Maximising throughput and yield while minimising costs and emissions.

Recently Completed Projects

C26007 Revised Dustiness And DEM Test Method (Update Of AS4156.6) Part 2:Preparation

In 2015 project C23054 investigated and reviewed the Australian Stan...

C22033Advanced Control And Optimisation Of DMC Operation

The objective of this project was to develop, implement and demonstr...

C24045Adaptation Of Coal Grain Analysis To Improve Flotation Yield Estimation

Yield estimation from resource data is notoriously difficult. Facto...

Coal Preparation

Technical Market Support

Market acceptance and emphasising the advantages of Australian coals.

Recently Completed Projects

C25045Stage Two - Assessment Of In Situ High-Temperature Strength Of Cokes

Stage I of this project established a reliable and repeatable proces...

C25044Trace Elements In Coal; Status Of Test Methods In Use And Their Applicability

 STAGE 1 REPORT

The key objectives of this stage...

C25042Mechanistic Model Of Coke Development In A Coke Oven Situation

The standard approach to evaluate the potential of coals or blends t...

Technical Market Support

Mine Site Greenhouse Mitigation

Mitigating greenhouse gas emissions from the production of coal.

Recently Completed Projects

C24061Proof-Of-Concept Photocatalytic Destruction Of Methane For Coal Mining Fugitive Emissions Abatement

Australia's fugitive emissions in 2015 were 41 Mt CO2-e (representin...

C23052Novel Stone Dust Looping Process For Ventilation Air Methane Abatement - Phase 3

This multi‐phase project is concerned with the mitigation of m...

C19054VAM Enrichment With A Two-Stage Adsorption Process

Treatment of ventilation air methane (VAM) with cost-effective technolog...

Mine Site Greenhouse Mitigation

Low Emission Coal Use

Step-change technologies aimed at reducing greenhouse gas emissions.

Recently Completed Projects

C17060BGasification Of Australian Coals

Four Australian coals were trialled in the Siemens 5 MWth pilot scale ga...

C17060AOxyfuel Technology For Carbon Capture And Storage Critical Clean Coal Technology - Interim Support

The status of oxy-fuel technology for first-generation plant is indicate...

C18007Review Of Underground Coal Gasification

This report consists of a broad review of underground coal gasification,...

Low Emission Coal Use

Mining And The Community

The relationship between mines and the local community.

Recently Completed Projects

C16027Assessing Housing And Labour Market Impacts Of Mining Developments In Bowen Basin Communities

The focus of this ACARP-funded project has been to identify a number...

C22029Understanding And Managing Cumulative Impacts Of Coal Mining And Other Land Uses In Regions With Diversified Economies

The coal industry operates in the context of competing land-uses that sh...

C23016Approval And Planning Assessment Of Black Coal Mines In NSW And Qld: A Review Of Economic Assessment Techniques

This reports on issues surrounding economic assessment and analysis ...

Mining And The Community

NERDDC

National Energy Research,Development & Demonstration Council (NERDDC) reports - pre 1992.

Recently Completed Projects

1609-C1609Self Heating of Spoil Piles from Open Cut Coal Mines

Self Heating of Spoil Piles from Open Cut Coal Mines

1301-C1301Stress Control Methods for Optimised Development...

Stress Control Methods for Optimised Development and Extraction Operations

0033-C1356Commissioned Report: Australian Thermal Coals...

Commissioned Report: Australian Thermal Coals - An Industry Handbook

NERDDC