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Cyclic haul operations are iterative transport operations, often performed by several haulers in a production work step. Cyclic haul operations are common in mining and quarry operations where the purpose of the haul work step is to move mass a relatively short distance e.g., from blasted rock supplies to the mass crushing and separation facility. The operation can include one or several haulers that perform the work simultaneously. When several haulers are used, they are generally not synchronized in an optimized way and operative variations and changes continuously affects the operation. An example of such variations can be that the driving speed and time required for certain maneuvers varies depending on driver skills and machine capacity. An operative change can be that the loading position is moved, leading to changed routes and varying distances. The operative characteristics of the haul work step indicates that there rarely exists a static state that the operators can learn to do efficiently. Our previous research has shown that haul operations can have a fuel reduction potential of up to 40%, depending on the operation characteristics and wastes such as unnecessary stops and waiting. This paper presents and assesses a system solution in a decentralized control system that calculates and advices operators with a speed for just in time arrival to a destination. The purpose of the system is to reduce fuel consumption with an obtained production rate. The system assessment shows that while production rate is obtained, fuel is reduced by up to 20% compared to base line operation in a simple quarry haul work step, including three haulers.

A Quarry and Aggregate production site consist of sequential production processes and activities to process and produce the output products. Compared to a fixed manufacturing plant, the quarry processes involve mobile machines such as wheel loaders, trucks and articulated haulers and a highly dynamic road infrastructure. Today, the mobile machines are generally not synchronized or controlled towards the overall throughput of the site in real time. This indicates a general improvement potential in increased productivity at quarry sites, but also unsolved challenges for the same reason. Assuming a wireless control system that controls speed and throughput of the different processes and activities, there would be a fuel reduction potential in controlling the mobile machines. This optimization requires models of machine fuel consumption for different applications, velocities and travel times. The main contribution of this paper is the presentation of fuel measurements based on different speeds, site application characteristics and travel times for hauling operation. The fuel measures reveal important aspects regarding how different velocities impact fuel consumption. The results of fuel measurements show a potential in fuel savings of up to 42% and a typical improvement of 20-30% depending on machine speeds, travel times, application and site characteristics. Based on this, some of the applications and challenges in wirelessly controlling machines are discussed.

Cyclic transport missions involving fleets of vehicles are common in quarry and mining operations and have shown to have a significant potential for energy optimization. Vehicles such as articulated haulers and dump trucks utilized in transport missions can be of different brand, type and have different performance characteristics such as engine power, traction and load. Vehicles may also be operated and owned by different organizations as they can be subcontracted to an operation. The transport operation characteristics include stochastic behaviors and activity times that fluctuate over time, and hence real-time control is required for efficient optimization. As the vehicles are mobile, wireless communication also needs to be available. As the constituent systems (vehicles) have managerial and operational independence, a system of systems approach is applicable. This paper provides an overview of the key characteristics and requirements for such a system and discusses the pros and cons of acknowledged and directed system architectures. Further, a case study is presented where an acknowledged system of systems is implemented in a real world mine and evaluated through a qualitative assessment of an operator assistive optimization system. Key findings include the drawbacks and characteristics of the architecture approaches. Further challenges and potential for automation and production control of a larger process system are described.

This paper investigates how wireless communication and vehicular ad hoc network (VANET) based technologies can be applied in relation to road construction work sites to improve safety and increase efficiency and sustainability. It discusses how to design the flow of data for a number of functions and how to operate the functions at the work site even at low VANET penetration rates. The applications described identify the potential in increased productivity at a road construction site and how increased visibility of site activities impact on traffic and improved road safety. It also highlights important implementation considerations and the need of availability and utilization of open standards for this purpose. © 2012 IEEE.

The operation of Quarry and Aggregate sites are similar to factory production, since it contains sequential production processes, tasks and activities to produce the output product. Compared to the plant though, the quarry processes are generally not synchronized and controlled towards the overall throughput of the site in real time. Some quarries control parts of the production but do generally not utilize real-time technologies for the whole site and all its activities. This fact indicates a general improvement potential in increased productivity at quarry sites, but also unsolved challenges for the same reason. The main contribution of this paper is the presentation of a Lean based method for how to describe the processes to identify control improvement potential within a site. The aim of the identified improvements is to increase overall site productivity by optimizing site, fleet and machine utilization towards the overall throughput, and minimizing operational expenses and inventories. Further the paper exemplifies the methodÂ’s usability with field studies at operational quarry plants successfully identifying and quantifying potential wastes and improvements. In addition the identified productivity improvements based on increased control and automation indicate challenges and needs in wireless communication and sensing technologies.

There is a large potential in automation and optimization of transports within quarry and mining, but operational models and characteristics for this purpose are lacking. This paper aims to provide insight into cyclic transports and the parameters that affect energy consumption and productivity. For this purpose, data from machines in operation has been collected and analyzed. The paper presents and discusses the characteristics of the operation identified, develops models for energy consumption and productivity, and discusses its relation for optimization and automation purposes. A conclusion is that there are stochastic fluctuations in activity times that need continuous real-time control for an optimization system to be effective. The method used in the paper resulted in regression models for cycle energy cost and hauler fuel rate, which provide both correlation and significance, which is promising for future validation and use in optimization control systems.