Torque and shift decision for quadri-motor mining truck based on expert-informed DDPG

This study investigates the factors influencing the energy consumption and reliability of haul trucks in open-pit mines and quarries, where fuel costs and the environmental impact are significant. Traditional analysis of haulage systems often overlooks crucial aspects such as energy efficiency in the specific mining environment and the effect of road configurations on truck performance. As sustainability becomes increasingly important, reducing fuel consumption not only reduces costs but also reduces greenhouse gas emissions. A key focus of the study is the link between haul truck reliability and overall efficiency. Frequent breakdowns increase maintenance costs, lead to unplanned downtime, and increase fuel consumption, all of which have an impact on the environment. Reliable transport systems, on the other hand, improve efficiency, reduce costs, and support sustainability goals. The authors analyze the energy consumption of trucks in relation to vehicle performance parameters and transport route characteristics. Discrete modeling of the transport system showed the impact of the operating environment on the variability of energy consumption and vehicle reliability. The study highlights the importance of understanding specific energy consumption in order to optimize the choice of transport system, as transport costs are a major cost of resource extraction. By analyzing the effect of road quality on vehicle performance, the authors suggest that improvements to the road surface can more easily improve vehicle reliability and energy intensity than changes to other road design elements. The study presents a quantitative analysis of the impact of haul road conditions on the operational efficiency of haul trucks in mining environments. Through discrete simulation models, two scenarios were analyzed. Total operational time decreased by 11.2% when road quality improved, demonstrating the critical role of surface maintenance. Additionally, breakdown times were reduced by 44%, maintenance by 15%, and empty travel by 9% in the optimized scenario. These findings underscore the necessity of maintaining optimal road conditions to prevent substantial efficiency losses and increased maintenance costs.

The field of study of autonomous trucks especially in open pit mines has been the subject of considerable research over the past three decades. In the last ten years in particular, interest in this area has improved considerably. The implementation of autonomous systems is an integral organizational and cultural change. This work is a guideline for the safe and effective implementation of autonomous trucks in mines. It provides an integral view of the different approaches to implementing autonomous mining trucks with respect to safety criteria, operating costs, etc. It also presents the criteria and measures to be considered when maintaining the haulage routes (vertical/horizontal/combined alignment) that are a vital component for the success of an automation project. Mine site designers and planners should ensure that the design and construction of traffic areas for these trucks are compatible with autonomy and minimize interactions with personnel and non-autonomous equipment. A proposed infrastructural requirement for the autonomous truck zone is presented in this work.

Dump trucks are used for transportation in opencast mines and consume about 32% of the total energy use in mines. This paper presents a generic model to benchmark energy consumption for dump trucks in mines. The modelling framework estimates minimum specific fuel consumption (SFC) of dump trucks using mine equipment, engine characteristics and vehicle dynamics. The model investigates the variation of SFC with operating input parameters like payload, material handling rate, vehicle speed, distance, mine gradient, etc. The applicability of the proposed model is illustrated through a case study of multiple dump trucks in a down gradient opencast limestone mine in India. The minimum SFC of 89g/t is estimated for a mine transport system with three excavators and two crushers. The case study shows a potential fuel saving of 17%. The modelling framework developed can be used to set rational targets for energy consumption for dump trucks in mines.

The mining trucks with heavy loads are widely used in open‐pit mines, which are usually under working conditions where the recoverable potential energy accounts for more than 1/3 of the traction energy. Therefore, it is important to study the existing energy recovery technologies suitable for mining trucks. This work presents a comparative study on the economy of a mining truck by integrating four different energy storage systems (ESS): battery, supercapacitor, hydraulic accumulator, and air tank combining with the existing internal combustion engine to form a hybrid mining truck. First, recent applications and features of the four ESSs in vehicles are discussed. Next, the configurations of four types of partial hybrid mining trucks are presented. In addition, this project compares different configurations by the total benefit over 10 years of operation. The compressed‐air ESS with full capacity obtained the best benefit under medium and heavy load scenarios, which is more applicable to the actual situations. Therefore, it will be beneficial to turn the conventional electric‐driving mining truck into a compressed‐air hybrid.

<div class="section abstract"><div class="htmlview paragraph">The need for energy is ever increasing, though the dependency on renewable energy have increased, it is not sufficient to cater the demand. India is one of fastest developing country which depends on coal 55% for its total energy need. To achieve coal digging & transportation an underground mining vehicle has gained high importance. Underground mine environment is inherently dangerous due to various factors, including explosive and toxic gases, dust, and the potential for collapses. Thereby vehicles running in coal mines requires extreme safety features to safeguard its operator & coal mine workers.</div><div class="htmlview paragraph">In India the Directorate General of Mines Safety (DGMS) under Government of India circulates notification to Manager of Coal and Metalliferous Mines & OEM, concerned about the minimum safety evaluations to be taken care for the mining trucks. It has been observed that there are significant inconsistencies in design practices for mining vehicles, with the presence of multiple, unverified types and models. In many cases, these designs lack conformity to established Indian or international standards, even where such standards are readily available. This not only compromises quality and reliability but also poses risks to safety and long-term sustainability. This Paper is providing complete guideline for required safety features for the latest available technology in underground mining trucks. This paper will take you through various standards available globally to insure safety of the operator. Further the Paper will provide complete solution for specific modifications in standard procedure to fit with Indian scenario.</div><div class="htmlview paragraph">Presently in India, Underground Mining trucks are not covered under Central Motor vehicle rules as the mining truck application is way different than the commercial trucks those ply on road. The paper gives guideline for having safety related compliances also touches upon performance & environment related compliances which aligns mining trucks safety through global practices and technology assessment. This paper will also guide for designers and engineers to consider various standards which shall support their study & design to meet listed standards required for mining truck application. This paper can be a guideline for mining industry & regulatory bodies in India for keeping technical standards & enhancement in technology so that new guidelines can be inclusive of latest standards requirements before deploying vehicles for underground mining activity.</div></div>

The high complexity and high computational resource requirements of the autonomous driving system require it to be designed not only to meet requirements of stringent integrity and security, but also to be iteratively updated over the life cycle of the vehicle as external systems evolve. In addition, the heavy mining trucks are severely bumped on the rough mining road, making the expensive lidar on the mining truck very vulnerable to damage, and if all sensors are deployed on the mining truck, there will also be a problem of excessive processing unit load. Aiming at the above problems, a design scheme of cooperative computing mining truck automatic driving system based on AUTOSAR Adaptive Platform is proposed. The design scheme includes a cloud control and management system, a vehicle control and management system and a road detection and identification system. The three-in-one, coordinated operation not only meets the needs of the automation and intelligence of the mining truck autonomous driving system, as well as unified management, operation and maintenance, but also supports high performance and collaborative computing, secure and reliable communication mechanisms and flexible software configuration capabilities.

Sumitomo Osaka Cement Co., Ltd., has developed and operated the Autonomous Mining Truck System (AMTS) for open-pit limestone mining in Shuhou Mine, Yamaguchi Pref., Japan. (the annual amount of products are 8 million metric tons, the total amount of products are 260 million metric tons) Epoch-making features of the AMTS are those it has the ability to control two mining trucks simultaneously, and it has the capability of operation on overlap areas with manned mining trucks. In addition, it has striking improvement when compared to the conventional system. This is the pioneering a trace control system in this country for mining trucks using Global Positioning System, and even if the case of changing hauling routes, it requires no replacement of the accessorial equipment on mining benches. From 1999, the AMTS joint development project with Shin Caterpillar Mitsubishi Ltd. (present; Caterpillar Japan Co., Ltd.) , has started by field tests with a CAT 775, 60 metric tons haul capacity in Shuho mine. Afterward the AMTS has been transferred to CAT789s, 180 metric tons haul capacity, and from 2007, it has been started to operate in the mining site. We worked on a construction of the AMTS under three severe concepts as follows. (1) The safety first, (2) Area overlap operation with manned mining trucks, (3) Investigating its convenience apply. In particular, for safely operation, we placed a priority on building the obstacle detection equipment that is required to be fit for variable situation in mining site, and it has been tuned well after much trial and error. Productivity of the AMTS performs about 70% as compared to manned operation, and some of haul labor saving have already been confirmed. Improvement works should make progress on utilization and productivity of the AMTS from now on.

The processes of the mining industry operate on a large scale, as well as its equipment, personnel, and facilities. It is necessary to plan the work and activities to measure and control its operations. In this sense, mining trucks are a fundamental piece of the board. One of the key indicators for assessing the maintenance process management is availability. To this end, a study and analysis of the performance of 980 E-5 mining trucks has been conducted, obtaining results of key indicators to measure and compare the productivity of the fleet. The quantitative method was applied, with notable results including a 20% increase in mean time between failures (MTBF), indicating improved mean times between truck failures. Mean Time to Repair (MTTR) experienced a slight 5.7% increase in repair time compared to the previous year. Availability saw a 3.3% increase from the contractual value of 91.18%. This was evidenced in the compliance and precision of preventive maintenance with an average frequency of 508 hours in total between each preventive maintenance.

SYNOPSIS Whole-body vibration (WBV) exposure measurements taken from 105 truck drivers employed in 19 mines and other workplaces were evaluated with the criteria prescribed in EU 2002/44/EC directive, BS 6841 (1987), ISO 2631-1 (1997). and ISO 2631-5 (2004) standards. The highest vibration acceleration was measured on the vertical Z-axis. The highest WBV exposure occurred in the RETURN, HAUL, and SPOT phases while the lowest exposure took place in the LOAD and WAIT phases. Crest factors on all axes were generally greater than nine, yet strong correlation coefficients were achieved in VDV-eVDV analyses. Driver seats generally dampened the vibration along the Z-axis but exacerbated it along X and Y axes. The dominant frequency for the X and Y-axes rose up to 40 Hz while it ranged between 1 Hz and 2.5 Hz along the Z-axis. While the probability of an adverse health effect was higher with BS 6841 (1987) and ISO 2631-1 (1997) standards, it was low according to EU 2002/44/EC and ISO 2631-5 (2004). The 91 t, 100 t, and 170 t capacity trucks produced lower vibration magnitudes. Drivers were exposed to approximately equivalent levels of WBV acceleration and dose in contractor-type trucks and mining trucks. Rear-dump trucks exposed their drivers to a slightly higher level of vibration than bottom-dump trucks. Underground trucks exposed their drivers to a significantly higher level of vibration than mining trucks. Both driver age and driver experience were inversely proportional to vibration acceleration and dose. Conversely, there was a positive relationship between the truck service years and the WBV acceleration and dose to which drivers were exposed to. Loads of blocky material exposed drivers to higher vibration acceleration and dose levels than non-blocky material. Keywords: whole-body vibration, mining truck, A(8), BS 6841, EU 2002/EC/44, ISO 2631-1, ISO 2631-5, VDV(8).

The significance in constructing a driving style identification model for open-pit mine truck drivers is to reduce diesel consumption and improve training. First, we developed a driving behavior and mining truck condition monitoring system for an open-pit mine. Under heavy-load and no-load conditions of a mining truck, based on the same experimental truck and haulage road, the data of driving behavior and truck status of different drivers were collected. The driving style characteristic parameters of mining trucks under heavy-load and no-load conditions were constructed through Pearson correlation analysis. Using a k-means clustering algorithm, driving style can be divided into three types: normal type, soft type, and aggressive type, and we verified the validity of this driving style classification with a box plot. On this basis, the parameters of random forest, k-nearest neighbor, support vector machine, and neural network models were optimized and the accuracy was compared through a cross-validation grid search, and then a driving style identification model based on the random forest method was finally proposed. Driving style parameter weight values were obtained based on the Gini coefficient. Last, the fuel consumption characteristics of different driving styles were calculated. The results show that the driving style identification models based on random forest can effectively identify different driving styles when the mining truck is operating under heavy load and no load, and the overall accuracy of the model is 95.39% and 90.74% respectively. The fuel consumption of the aggressive driving style was the largest and was 10% higher than the average fuel consumption. The research results provide data support and new ideas for operation training and fuel-saving driving of mining trucks in open-pit mines.

<div class="section abstract"><div class="htmlview paragraph">A range of axle suspensions, comprising hydro-pneumatic struts and diverse linkage configurations, have evolved in recent years for large size mining trucks to achieve improved ride and higher operating speeds. This paper presents a comprehensive analysis of different independent front suspension linkages that have been implemented in various off-road vehicles, including a composite linkage (CL), a candle (CA), a trailing arm (TA), and a double Wishbone (DW) suspension applied to a 190 tons mining truck. Four different suspension linkages are modeled in MapleSim platform to evaluate their kinematic properties. The relative kinematic properties of the suspensions are evaluated in terms of variations in the kingpin inclination, caster, camber, toe-in and horizontal wheel center displacements considering the motion of a hydro-pneumatic strut. The results revealed the CL and DW suspensions yield superior kinematic response characteristics compared to the CA and TA suspensions. Toe-in and horizontal wheel center displacements of the CA and TA vary significantly, which could strongly affect the vehicle handling performance and cause greater tire wear. The CL and DW suspensions may thus be considered desirable for future designs of high-speed and high-performance mining trucks.</div></div>

Automatic gear shift strategy for manual transmission of mine truck based on Bi-LSTM network

By analyzing the configuration and operation plan of mining equipment, this paper establishes a linear programming model and converts it into the corresponding quadratic unconstrained binary optimization (QUBO) form. Based on this, the simulated annealing solver built-in in Kaiwu SDK and CIM simulator are used to study the configuration and operation plan of mining equipment. For work one: it is required to provide a procurement plan that maximizes profits within the budget range, that is, to determine the required excavator models and corresponding quantities. This problem is based on the premise of not considering the service life of excavators, with the maximum value of the product of the four excavator models and their corresponding long-term profits and quantities as the objective function, and with the constraints of start-up capital budget and excavator type, a 0-1 integer programming model is established. By using the decision variable of the model as a 0-1 variable and the constraint as an inequality constraint, the constraint is then transformed into the corresponding Hamiltonian operator, and the penalty term coefficient P is introduced and added to the objective function, thereby transforming it into QUBO form. Due to the low complexity and linearity of the model, the Kaiwu SDK's built-in simulated annealing solver and CIM simulator were used to solve the problem and obtain the final maximum profit and procurement plan. For work two: compared to work one, the condition of equipment lifespan of 5 years has been added, and it is required to plan the model and quantity of excavators that need to be purchased, while providing the matching relationship between excavators and mining trucks. This problem requires consideration of various cost conditions, with the difference between revenue and cost within five years as the objective function, and matching constraints, quantity constraints, and budget constraints as constraints, ultimately constructing a general linear programming model. By using inequality constraint relationships, the relaxation variable s in binary expression is introduced to express the constraint term, thereby transforming it into QUBO form. Afterwards, Kaiwu SDK was used to solve the procurement plan and obtain the matching relationship between excavators and mining trucks. For work three: Based on work two, the number of devices has been increased. For the constructed linear programming model, it can be transformed into a QUBO model or even a subQUBO model. Firstly, preprocess the data and use Spearman correlation analysis to determine the degree of correlation between the data, visualizing the data. For the constructed linear programming model, compared to problem two, only parameter variables were added, and the constraint conditions were consistent with problem two. A relaxation variable s was introduced to construct a constraint term, which was then transformed into a QUBO model. Combined with classical calculations, the subQUBO method was used. Finally, the procurement plan was obtained through Kaiwu SDK and a new matching relationship between excavators and mining trucks was provided. **************** ACKNOWLEDGEMENTS**************** This work is supported by ministry of education industry-university cooperative education project (Grant No.: 231106441092432), the research and practice of integrating "curriculum thought and politics" into the whole process of graduation design of Mechanical engineering major: (Grant. No.: 30120300100-23-yb-jgkt03), research on the integration mechanism of "course-training-competition-creation-production" for innovation and entrepreneurship of mechanical engineering majors in applied local universities (Grant. No.: CXKT202405), Mechanical manufacturing equipment design school-level "gold class" construction project (Grant. No.: 30120324001).

Research analysis on the airflow-particle migration and dust disaster impact scope by the moving mining truck in the open-pit mine

Distributed drive electric mining trucks’ active safety and driving economy are inseparably associated with chassis integration control. In order to ensure the safety and economy of mining trucks under complex and variable working conditions, the key technologies and research development of chassis integration control for distributed drive electric mining trucks are overviewed in terms of truck handling stability control, dynamics integration control, and chassis fault-tolerance control, and energy-saving control. Aiming at the longitudinal instability, yaw, roll, and pitch of mining trucks, the truck longitudinal, lateral, and vertical stability control methods are described comprehensively, and the coupled and integrated control strategies between the systems are compared. Distributed drive electric vehicle chassis cooperative fault-tolerant control methods are outlined, and the effectiveness of chassis cooperative fault-tolerant control applied to mining trucks is demonstrated. Regarding the feedback energy to improve the economy of distributed drive electric mining trucks, an electro-hydraulic brake energy recovery method combining anti-lock brakes and hydraulic brakes is summarized, coupled with lateral and vertical dynamics. Furthermore, the torque distribution method that considers the truck driving stability and improves the driving economy is overviewed systematically. Finally, the development prospects of the chassis integrated control of distributed drive electric mining trucks are foreseen.